* [RFC PATCH for 4.18 06/16] x86: Add support for restartable sequences (v2)
From: Mathieu Desnoyers @ 2018-06-02 12:43 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
Call the rseq_handle_notify_resume() function on return to userspace if
TIF_NOTIFY_RESUME thread flag is set.
Perform fixup on the pre-signal frame when a signal is delivered on top
of a restartable sequence critical section.
Check that system calls are not invoked from within rseq critical
sections by invoking rseq_signal() from syscall_return_slowpath().
With CONFIG_DEBUG_RSEQ, such behavior results in termination of the
process with SIGSEGV.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-api@vger.kernel.org
---
Changes since v1:
- Call rseq_signal() when returning from a system call.
---
arch/x86/Kconfig | 1 +
arch/x86/entry/common.c | 3 +++
arch/x86/kernel/signal.c | 6 ++++++
3 files changed, 10 insertions(+)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c07f492b871a..62e00a1a7cf7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -180,6 +180,7 @@ config X86
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
select HAVE_STACK_VALIDATION if X86_64
+ select HAVE_RSEQ
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_USER_RETURN_NOTIFIER
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index fbf6a6c3fd2d..92190879b228 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -164,6 +164,7 @@ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
if (cached_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
+ rseq_handle_notify_resume(regs);
}
if (cached_flags & _TIF_USER_RETURN_NOTIFY)
@@ -254,6 +255,8 @@ __visible inline void syscall_return_slowpath(struct pt_regs *regs)
WARN(irqs_disabled(), "syscall %ld left IRQs disabled", regs->orig_ax))
local_irq_enable();
+ rseq_syscall(regs);
+
/*
* First do one-time work. If these work items are enabled, we
* want to run them exactly once per syscall exit with IRQs on.
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index da270b95fe4d..445ca11ff863 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -688,6 +688,12 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
sigset_t *set = sigmask_to_save();
compat_sigset_t *cset = (compat_sigset_t *) set;
+ /*
+ * Increment event counter and perform fixup for the pre-signal
+ * frame.
+ */
+ rseq_signal_deliver(regs);
+
/* Set up the stack frame */
if (is_ia32_frame(ksig)) {
if (ksig->ka.sa.sa_flags & SA_SIGINFO)
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 07/16] x86: Wire up restartable sequence system call
From: Mathieu Desnoyers @ 2018-06-02 12:43 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
Wire up the rseq system call on x86 32/64.
This provides an ABI improving the speed of a user-space getcpu
operation on x86 by removing the need to perform a function call, "lsl"
instruction, or system call on the fast path, as well as improving the
speed of user-space operations on per-cpu data.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-api@vger.kernel.org
---
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
2 files changed, 2 insertions(+)
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index d6b27dab1b30..db346da64947 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -396,3 +396,4 @@
382 i386 pkey_free sys_pkey_free __ia32_sys_pkey_free
383 i386 statx sys_statx __ia32_sys_statx
384 i386 arch_prctl sys_arch_prctl __ia32_compat_sys_arch_prctl
+385 i386 rseq sys_rseq __ia32_sys_rseq
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 4dfe42666d0c..41b082b125c3 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -341,6 +341,7 @@
330 common pkey_alloc __x64_sys_pkey_alloc
331 common pkey_free __x64_sys_pkey_free
332 common statx __x64_sys_statx
+333 common rseq __x64_sys_rseq
#
# x32-specific system call numbers start at 512 to avoid cache impact
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 08/16] powerpc: Add support for restartable sequences
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers,
Benjamin Herrenschmidt <benh>
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
From: Boqun Feng <boqun.feng@gmail.com>
Call the rseq_handle_notify_resume() function on return to userspace if
TIF_NOTIFY_RESUME thread flag is set.
Perform fixup on the pre-signal when a signal is delivered on top of a
restartable sequence critical section.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Peter Zijlstra <peterz@infradead.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: linuxppc-dev@lists.ozlabs.org
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/kernel/signal.c | 3 +++
2 files changed, 4 insertions(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index c32a181a7cbb..ed21a777e8c6 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -223,6 +223,7 @@ config PPC
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_VIRT_CPU_ACCOUNTING
select HAVE_IRQ_TIME_ACCOUNTING
+ select HAVE_RSEQ
select IRQ_DOMAIN
select IRQ_FORCED_THREADING
select MODULES_USE_ELF_RELA
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index 61db86ecd318..d3bb3aaaf5ac 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -133,6 +133,8 @@ static void do_signal(struct task_struct *tsk)
/* Re-enable the breakpoints for the signal stack */
thread_change_pc(tsk, tsk->thread.regs);
+ rseq_signal_deliver(tsk->thread.regs);
+
if (is32) {
if (ksig.ka.sa.sa_flags & SA_SIGINFO)
ret = handle_rt_signal32(&ksig, oldset, tsk);
@@ -164,6 +166,7 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
+ rseq_handle_notify_resume(regs);
}
user_enter();
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 09/16] powerpc: Add syscall detection for restartable sequences
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers,
Benjamin Herrenschmidt <benh>
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
From: Boqun Feng <boqun.feng@gmail.com>
Syscalls are not allowed inside restartable sequences, so add a call to
rseq_syscall() at the very beginning of system call exiting path for
CONFIG_DEBUG_RSEQ=y kernel. This could help us to detect whether there
is a syscall issued inside restartable sequences.
[ Tested on 64-bit powerpc kernel by Mathieu Desnoyers. Still needs to
be tested on 32-bit powerpc kernel. ]
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Peter Zijlstra <peterz@infradead.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: linuxppc-dev@lists.ozlabs.org
---
arch/powerpc/kernel/entry_32.S | 7 +++++++
arch/powerpc/kernel/entry_64.S | 8 ++++++++
2 files changed, 15 insertions(+)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index eb8d01bae8c6..973577f2141c 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -365,6 +365,13 @@ syscall_dotrace_cont:
blrl /* Call handler */
.globl ret_from_syscall
ret_from_syscall:
+#ifdef CONFIG_DEBUG_RSEQ
+ /* Check whether the syscall is issued inside a restartable sequence */
+ stw r3,GPR3(r1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl rseq_syscall
+ lwz r3,GPR3(r1)
+#endif
mr r6,r3
CURRENT_THREAD_INFO(r12, r1)
/* disable interrupts so current_thread_info()->flags can't change */
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 51695608c68b..1c374387656a 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -184,6 +184,14 @@ system_call: /* label this so stack traces look sane */
.Lsyscall_exit:
std r3,RESULT(r1)
+
+#ifdef CONFIG_DEBUG_RSEQ
+ /* Check whether the syscall is issued inside a restartable sequence */
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ bl rseq_syscall
+ ld r3,RESULT(r1)
+#endif
+
CURRENT_THREAD_INFO(r12, r1)
ld r8,_MSR(r1)
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 10/16] powerpc: Wire up restartable sequences system call
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers,
Benjamin Herrenschmidt <benh>
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
From: Boqun Feng <boqun.feng@gmail.com>
Wire up the rseq system call on powerpc.
This provides an ABI improving the speed of a user-space getcpu
operation on powerpc by skipping the getcpu system call on the fast
path, as well as improving the speed of user-space operations on per-cpu
data compared to using load-reservation/store-conditional atomics.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: Michael Ellerman <mpe@ellerman.id.au>
CC: Peter Zijlstra <peterz@infradead.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: linuxppc-dev@lists.ozlabs.org
---
arch/powerpc/include/asm/systbl.h | 1 +
arch/powerpc/include/asm/unistd.h | 2 +-
arch/powerpc/include/uapi/asm/unistd.h | 1 +
3 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index d61f9c96d916..45d4d37495fd 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -392,3 +392,4 @@ SYSCALL(statx)
SYSCALL(pkey_alloc)
SYSCALL(pkey_free)
SYSCALL(pkey_mprotect)
+SYSCALL(rseq)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index daf1ba97a00c..1e9708632dce 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -12,7 +12,7 @@
#include <uapi/asm/unistd.h>
-#define NR_syscalls 387
+#define NR_syscalls 388
#define __NR__exit __NR_exit
diff --git a/arch/powerpc/include/uapi/asm/unistd.h b/arch/powerpc/include/uapi/asm/unistd.h
index 389c36fd8299..ac5ba55066dd 100644
--- a/arch/powerpc/include/uapi/asm/unistd.h
+++ b/arch/powerpc/include/uapi/asm/unistd.h
@@ -398,5 +398,6 @@
#define __NR_pkey_alloc 384
#define __NR_pkey_free 385
#define __NR_pkey_mprotect 386
+#define __NR_rseq 387
#endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 11/16] selftests: lib.mk: Introduce OVERRIDE_TARGETS
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers,
linux-kselftest
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
Introduce OVERRIDE_TARGETS to allow tests to express dependencies on
header files and .so, which require to override the selftests lib.mk
targets.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
tools/testing/selftests/lib.mk | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index c1b1a4dc6a96..ceb6c7c48547 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -106,6 +106,9 @@ COMPILE.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c
LINK.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH)
endif
+# Selftest makefiles can override those targets by setting
+# OVERRIDE_TARGETS = 1.
+ifeq ($(OVERRIDE_TARGETS),)
$(OUTPUT)/%:%.c
$(LINK.c) $^ $(LDLIBS) -o $@
@@ -114,5 +117,6 @@ $(OUTPUT)/%.o:%.S
$(OUTPUT)/%:%.S
$(LINK.S) $^ $(LDLIBS) -o $@
+endif
.PHONY: run_tests all clean install emit_tests
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 12/16] rseq: selftests: Provide rseq library (v5)
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers, Shuah Khan
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
This rseq helper library provides a user-space API to the rseq()
system call.
The rseq fast-path exposes the instruction pointer addresses where the
rseq assembly blocks begin and end, as well as the associated abort
instruction pointer, in the __rseq_table section. This section allows
debuggers may know where to place breakpoints when single-stepping
through assembly blocks which may be aborted at any point by the kernel.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
Changes since v1:
- Provide abort-ip signature: The abort-ip signature is located just
before the abort-ip target. It is currently hardcoded, but a
user-space application could use the __rseq_table to iterate on all
abort-ip targets and use a random value as signature if needed in the
future.
- Add rseq_prepare_unload(): Libraries and JIT code using rseq critical
sections need to issue rseq_prepare_unload() on each thread at least
once before reclaim of struct rseq_cs.
- Use initial-exec TLS model, non-weak symbol: The initial-exec model is
signal-safe, whereas the global-dynamic model is not. Remove the
"weak" symbol attribute from the __rseq_abi in rseq.c. The rseq.so
library will have ownership of that symbol, and there is not reason for
an application or user library to try to define that symbol.
The expected use is to link against libreq.so, which owns and provide
that symbol.
- Set cpu_id to -2 on register error
- Add rseq_len syscall parameter, rseq_cs version
- Ensure disassember-friendly signature: x86 32/64 disassembler have a
hard time decoding the instruction stream after a bad instruction. Use
a nopl instruction to encode the signature. Suggested by Andy Lutomirski.
- Exercise parametrized tests variants in a shell scripts.
- Restartable sequences selftests: Remove use of event counter.
- Use cpu_id_start field: With the cpu_id_start field, the C
preparation phase of the fast-path does not need to compare cpu_id < 0
anymore.
- Signal-safe registration and refcounting: Allow libraries using
librseq.so to register it from signal handlers.
- Use OVERRIDE_TARGETS in makefile.
- Use "m" constraints for rseq_cs field.
Changes since v2:
- Update based on Thomas Gleixner's comments.
Changes since v3:
- Generate param_test_skip_fastpath and param_test_benchmark with
-DSKIP_FASTPATH and -DBENCHMARK (respectively). Add param_test_fastpath
to run_param_test.sh.
Changes since v4:
- Fold arm: workaround gcc asm size guess,
- Namespace barrier() -> rseq_barrier() in library header,
- Take into account coding style feedback from Peter Zijlstra,
- Split rseq selftests into logical commits.
---
tools/testing/selftests/rseq/rseq-arm.h | 715 +++++++++++++++++++
tools/testing/selftests/rseq/rseq-ppc.h | 671 ++++++++++++++++++
tools/testing/selftests/rseq/rseq-skip.h | 65 ++
tools/testing/selftests/rseq/rseq-x86.h | 1132 ++++++++++++++++++++++++++++++
tools/testing/selftests/rseq/rseq.c | 117 +++
tools/testing/selftests/rseq/rseq.h | 147 ++++
6 files changed, 2847 insertions(+)
create mode 100644 tools/testing/selftests/rseq/rseq-arm.h
create mode 100644 tools/testing/selftests/rseq/rseq-ppc.h
create mode 100644 tools/testing/selftests/rseq/rseq-skip.h
create mode 100644 tools/testing/selftests/rseq/rseq-x86.h
create mode 100644 tools/testing/selftests/rseq/rseq.c
create mode 100644 tools/testing/selftests/rseq/rseq.h
diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h
new file mode 100644
index 000000000000..3b055f9aeaab
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq-arm.h
@@ -0,0 +1,715 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * rseq-arm.h
+ *
+ * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#define RSEQ_SIG 0x53053053
+
+#define rseq_smp_mb() __asm__ __volatile__ ("dmb" ::: "memory", "cc")
+#define rseq_smp_rmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc")
+#define rseq_smp_wmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc")
+
+#define rseq_smp_load_acquire(p) \
+__extension__ ({ \
+ __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
+ rseq_smp_mb(); \
+ ____p1; \
+})
+
+#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb()
+
+#define rseq_smp_store_release(p, v) \
+do { \
+ rseq_smp_mb(); \
+ RSEQ_WRITE_ONCE(*p, v); \
+} while (0)
+
+#ifdef RSEQ_SKIP_FASTPATH
+#include "rseq-skip.h"
+#else /* !RSEQ_SKIP_FASTPATH */
+
+#define __RSEQ_ASM_DEFINE_TABLE(version, flags, start_ip, \
+ post_commit_offset, abort_ip) \
+ ".pushsection __rseq_table, \"aw\"\n\t" \
+ ".balign 32\n\t" \
+ ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_DEFINE_TABLE(start_ip, post_commit_ip, abort_ip) \
+ __RSEQ_ASM_DEFINE_TABLE(0x0, 0x0, start_ip, \
+ (post_commit_ip - start_ip), abort_ip)
+
+#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
+ RSEQ_INJECT_ASM(1) \
+ "adr r0, " __rseq_str(cs_label) "\n\t" \
+ "str r0, %[" __rseq_str(rseq_cs) "]\n\t" \
+ __rseq_str(label) ":\n\t"
+
+#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
+ RSEQ_INJECT_ASM(2) \
+ "ldr r0, %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "cmp %[" __rseq_str(cpu_id) "], r0\n\t" \
+ "bne " __rseq_str(label) "\n\t"
+
+#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
+ abort_label, version, flags, \
+ start_ip, post_commit_offset, abort_ip) \
+ __rseq_str(table_label) ":\n\t" \
+ ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \
+ ".word " __rseq_str(RSEQ_SIG) "\n\t" \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "b %l[" __rseq_str(abort_label) "]\n\t"
+
+#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \
+ start_ip, post_commit_ip, abort_ip) \
+ __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
+ abort_label, 0x0, 0x0, start_ip, \
+ (post_commit_ip - start_ip), abort_ip)
+
+#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "b %l[" __rseq_str(cmpfail_label) "]\n\t"
+
+#define rseq_workaround_gcc_asm_size_guess() __asm__ __volatile__("")
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[error2]\n\t"
+#endif
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
+ off_t voffp, intptr_t *load, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expectnot], r0\n\t"
+ "beq %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "ldr r0, %[v]\n\t"
+ "cmp %[expectnot], r0\n\t"
+ "beq %l[error2]\n\t"
+#endif
+ "str r0, %[load]\n\t"
+ "add r0, %[voffp]\n\t"
+ "ldr r0, [r0]\n\t"
+ /* final store */
+ "str r0, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expectnot] "r" (expectnot),
+ [voffp] "Ir" (voffp),
+ [load] "m" (*load)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_addv(intptr_t *v, intptr_t count, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+#endif
+ "ldr r0, %[v]\n\t"
+ "add r0, %[count]\n\t"
+ /* final store */
+ "str r0, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(4)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [v] "m" (*v),
+ [count] "Ir" (count)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort
+#ifdef RSEQ_COMPARE_TWICE
+ , error1
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[error2]\n\t"
+#endif
+ /* try store */
+ "str %[newv2], %[v2]\n\t"
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[error2]\n\t"
+#endif
+ /* try store */
+ "str %[newv2], %[v2]\n\t"
+ RSEQ_INJECT_ASM(5)
+ "dmb\n\t" /* full mb provides store-release */
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t expect2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+ "ldr r0, %[v2]\n\t"
+ "cmp %[expect2], r0\n\t"
+ "bne %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(5)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne %l[error2]\n\t"
+ "ldr r0, %[v2]\n\t"
+ "cmp %[expect2], r0\n\t"
+ "bne %l[error3]\n\t"
+#endif
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ "b 5f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
+ "5:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* cmp2 input */
+ [v2] "m" (*v2),
+ [expect2] "r" (expect2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2, error3
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("1st expected value comparison failed");
+error3:
+ rseq_bug("2nd expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ uint32_t rseq_scratch[3];
+
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ "str %[src], %[rseq_scratch0]\n\t"
+ "str %[dst], %[rseq_scratch1]\n\t"
+ "str %[len], %[rseq_scratch2]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne 5f\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne 7f\n\t"
+#endif
+ /* try memcpy */
+ "cmp %[len], #0\n\t" \
+ "beq 333f\n\t" \
+ "222:\n\t" \
+ "ldrb %%r0, [%[src]]\n\t" \
+ "strb %%r0, [%[dst]]\n\t" \
+ "adds %[src], #1\n\t" \
+ "adds %[dst], #1\n\t" \
+ "subs %[len], #1\n\t" \
+ "bne 222b\n\t" \
+ "333:\n\t" \
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t"
+ "b 8f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ abort, 1b, 2b, 4f)
+ RSEQ_ASM_DEFINE_CMPFAIL(5,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ cmpfail)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_DEFINE_CMPFAIL(6,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ error1)
+ RSEQ_ASM_DEFINE_CMPFAIL(7,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ error2)
+#endif
+ "8:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len),
+ [rseq_scratch0] "m" (rseq_scratch[0]),
+ [rseq_scratch1] "m" (rseq_scratch[1]),
+ [rseq_scratch2] "m" (rseq_scratch[2])
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_workaround_gcc_asm_size_guess();
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_workaround_gcc_asm_size_guess();
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ uint32_t rseq_scratch[3];
+
+ RSEQ_INJECT_C(9)
+
+ rseq_workaround_gcc_asm_size_guess();
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(1f, 2f, 4f) /* start, commit, abort */
+ "str %[src], %[rseq_scratch0]\n\t"
+ "str %[dst], %[rseq_scratch1]\n\t"
+ "str %[len], %[rseq_scratch2]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne 5f\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ "ldr r0, %[v]\n\t"
+ "cmp %[expect], r0\n\t"
+ "bne 7f\n\t"
+#endif
+ /* try memcpy */
+ "cmp %[len], #0\n\t" \
+ "beq 333f\n\t" \
+ "222:\n\t" \
+ "ldrb %%r0, [%[src]]\n\t" \
+ "strb %%r0, [%[dst]]\n\t" \
+ "adds %[src], #1\n\t" \
+ "adds %[dst], #1\n\t" \
+ "subs %[len], #1\n\t" \
+ "bne 222b\n\t" \
+ "333:\n\t" \
+ RSEQ_INJECT_ASM(5)
+ "dmb\n\t" /* full mb provides store-release */
+ /* final store */
+ "str %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t"
+ "b 8f\n\t"
+ RSEQ_ASM_DEFINE_ABORT(3, 4,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ abort, 1b, 2b, 4f)
+ RSEQ_ASM_DEFINE_CMPFAIL(5,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ cmpfail)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_DEFINE_CMPFAIL(6,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ error1)
+ RSEQ_ASM_DEFINE_CMPFAIL(7,
+ /* teardown */
+ "ldr %[len], %[rseq_scratch2]\n\t"
+ "ldr %[dst], %[rseq_scratch1]\n\t"
+ "ldr %[src], %[rseq_scratch0]\n\t",
+ error2)
+#endif
+ "8:\n\t"
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len),
+ [rseq_scratch0] "m" (rseq_scratch[0]),
+ [rseq_scratch1] "m" (rseq_scratch[1]),
+ [rseq_scratch2] "m" (rseq_scratch[2])
+ RSEQ_INJECT_INPUT
+ : "r0", "memory", "cc"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ rseq_workaround_gcc_asm_size_guess();
+ return 0;
+abort:
+ rseq_workaround_gcc_asm_size_guess();
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ rseq_workaround_gcc_asm_size_guess();
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_workaround_gcc_asm_size_guess();
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_workaround_gcc_asm_size_guess();
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+#endif /* !RSEQ_SKIP_FASTPATH */
diff --git a/tools/testing/selftests/rseq/rseq-ppc.h b/tools/testing/selftests/rseq/rseq-ppc.h
new file mode 100644
index 000000000000..52630c9f42be
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq-ppc.h
@@ -0,0 +1,671 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * rseq-ppc.h
+ *
+ * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * (C) Copyright 2016-2018 - Boqun Feng <boqun.feng@gmail.com>
+ */
+
+#define RSEQ_SIG 0x53053053
+
+#define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory", "cc")
+#define rseq_smp_lwsync() __asm__ __volatile__ ("lwsync" ::: "memory", "cc")
+#define rseq_smp_rmb() rseq_smp_lwsync()
+#define rseq_smp_wmb() rseq_smp_lwsync()
+
+#define rseq_smp_load_acquire(p) \
+__extension__ ({ \
+ __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
+ rseq_smp_lwsync(); \
+ ____p1; \
+})
+
+#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_lwsync()
+
+#define rseq_smp_store_release(p, v) \
+do { \
+ rseq_smp_lwsync(); \
+ RSEQ_WRITE_ONCE(*p, v); \
+} while (0)
+
+#ifdef RSEQ_SKIP_FASTPATH
+#include "rseq-skip.h"
+#else /* !RSEQ_SKIP_FASTPATH */
+
+/*
+ * The __rseq_table section can be used by debuggers to better handle
+ * single-stepping through the restartable critical sections.
+ */
+
+#ifdef __PPC64__
+
+#define STORE_WORD "std "
+#define LOAD_WORD "ld "
+#define LOADX_WORD "ldx "
+#define CMP_WORD "cmpd "
+
+#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \
+ start_ip, post_commit_offset, abort_ip) \
+ ".pushsection __rseq_table, \"aw\"\n\t" \
+ ".balign 32\n\t" \
+ __rseq_str(label) ":\n\t" \
+ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
+ RSEQ_INJECT_ASM(1) \
+ "lis %%r17, (" __rseq_str(cs_label) ")@highest\n\t" \
+ "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@higher\n\t" \
+ "rldicr %%r17, %%r17, 32, 31\n\t" \
+ "oris %%r17, %%r17, (" __rseq_str(cs_label) ")@high\n\t" \
+ "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \
+ "std %%r17, %[" __rseq_str(rseq_cs) "]\n\t" \
+ __rseq_str(label) ":\n\t"
+
+#else /* #ifdef __PPC64__ */
+
+#define STORE_WORD "stw "
+#define LOAD_WORD "lwz "
+#define LOADX_WORD "lwzx "
+#define CMP_WORD "cmpw "
+
+#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \
+ start_ip, post_commit_offset, abort_ip) \
+ ".pushsection __rseq_table, \"aw\"\n\t" \
+ ".balign 32\n\t" \
+ __rseq_str(label) ":\n\t" \
+ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ /* 32-bit only supported on BE */ \
+ ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) "\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
+ RSEQ_INJECT_ASM(1) \
+ "lis %%r17, (" __rseq_str(cs_label) ")@ha\n\t" \
+ "addi %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \
+ "stw %%r17, %[" __rseq_str(rseq_cs) "]\n\t" \
+ __rseq_str(label) ":\n\t"
+
+#endif /* #ifdef __PPC64__ */
+
+#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
+ __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
+ (post_commit_ip - start_ip), abort_ip)
+
+#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
+ RSEQ_INJECT_ASM(2) \
+ "lwz %%r17, %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "cmpw cr7, %[" __rseq_str(cpu_id) "], %%r17\n\t" \
+ "bne- cr7, " __rseq_str(label) "\n\t"
+
+#define RSEQ_ASM_DEFINE_ABORT(label, abort_label) \
+ ".pushsection __rseq_failure, \"ax\"\n\t" \
+ ".long " __rseq_str(RSEQ_SIG) "\n\t" \
+ __rseq_str(label) ":\n\t" \
+ "b %l[" __rseq_str(abort_label) "]\n\t" \
+ ".popsection\n\t"
+
+/*
+ * RSEQ_ASM_OPs: asm operations for rseq
+ * RSEQ_ASM_OP_R_*: has hard-code registers in it
+ * RSEQ_ASM_OP_* (else): doesn't have hard-code registers(unless cr7)
+ */
+#define RSEQ_ASM_OP_CMPEQ(var, expect, label) \
+ LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \
+ CMP_WORD "cr7, %%r17, %[" __rseq_str(expect) "]\n\t" \
+ "bne- cr7, " __rseq_str(label) "\n\t"
+
+#define RSEQ_ASM_OP_CMPNE(var, expectnot, label) \
+ LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \
+ CMP_WORD "cr7, %%r17, %[" __rseq_str(expectnot) "]\n\t" \
+ "beq- cr7, " __rseq_str(label) "\n\t"
+
+#define RSEQ_ASM_OP_STORE(value, var) \
+ STORE_WORD "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t"
+
+/* Load @var to r17 */
+#define RSEQ_ASM_OP_R_LOAD(var) \
+ LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t"
+
+/* Store r17 to @var */
+#define RSEQ_ASM_OP_R_STORE(var) \
+ STORE_WORD "%%r17, %[" __rseq_str(var) "]\n\t"
+
+/* Add @count to r17 */
+#define RSEQ_ASM_OP_R_ADD(count) \
+ "add %%r17, %[" __rseq_str(count) "], %%r17\n\t"
+
+/* Load (r17 + voffp) to r17 */
+#define RSEQ_ASM_OP_R_LOADX(voffp) \
+ LOADX_WORD "%%r17, %[" __rseq_str(voffp) "], %%r17\n\t"
+
+/* TODO: implement a faster memcpy. */
+#define RSEQ_ASM_OP_R_MEMCPY() \
+ "cmpdi %%r19, 0\n\t" \
+ "beq 333f\n\t" \
+ "addi %%r20, %%r20, -1\n\t" \
+ "addi %%r21, %%r21, -1\n\t" \
+ "222:\n\t" \
+ "lbzu %%r18, 1(%%r20)\n\t" \
+ "stbu %%r18, 1(%%r21)\n\t" \
+ "addi %%r19, %%r19, -1\n\t" \
+ "cmpdi %%r19, 0\n\t" \
+ "bne 222b\n\t" \
+ "333:\n\t" \
+
+#define RSEQ_ASM_OP_R_FINAL_STORE(var, post_commit_label) \
+ STORE_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \
+ __rseq_str(post_commit_label) ":\n\t"
+
+#define RSEQ_ASM_OP_FINAL_STORE(value, var, post_commit_label) \
+ STORE_WORD "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t" \
+ __rseq_str(post_commit_label) ":\n\t"
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+#endif
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
+ off_t voffp, intptr_t *load, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v not equal to @expectnot */
+ RSEQ_ASM_OP_CMPNE(v, expectnot, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v not equal to @expectnot */
+ RSEQ_ASM_OP_CMPNE(v, expectnot, %l[error2])
+#endif
+ /* load the value of @v */
+ RSEQ_ASM_OP_R_LOAD(v)
+ /* store it in @load */
+ RSEQ_ASM_OP_R_STORE(load)
+ /* dereference voffp(v) */
+ RSEQ_ASM_OP_R_LOADX(voffp)
+ /* final store the value at voffp(v) */
+ RSEQ_ASM_OP_R_FINAL_STORE(v, 2)
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expectnot] "r" (expectnot),
+ [voffp] "b" (voffp),
+ [load] "m" (*load)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_addv(intptr_t *v, intptr_t count, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+#endif
+ /* load the value of @v */
+ RSEQ_ASM_OP_R_LOAD(v)
+ /* add @count to it */
+ RSEQ_ASM_OP_R_ADD(count)
+ /* final store */
+ RSEQ_ASM_OP_R_FINAL_STORE(v, 2)
+ RSEQ_INJECT_ASM(4)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [count] "r" (count)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort
+#ifdef RSEQ_COMPARE_TWICE
+ , error1
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+#endif
+ /* try store */
+ RSEQ_ASM_OP_STORE(newv2, v2)
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+#endif
+ /* try store */
+ RSEQ_ASM_OP_STORE(newv2, v2)
+ RSEQ_INJECT_ASM(5)
+ /* for 'release' */
+ "lwsync\n\t"
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t expect2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+ /* cmp @v2 equal to @expct2 */
+ RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[cmpfail])
+ RSEQ_INJECT_ASM(5)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+ /* cmp @v2 equal to @expct2 */
+ RSEQ_ASM_OP_CMPEQ(v2, expect2, %l[error3])
+#endif
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* cmp2 input */
+ [v2] "m" (*v2),
+ [expect2] "r" (expect2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2, error3
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("1st expected value comparison failed");
+error3:
+ rseq_bug("2nd expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* setup for mempcy */
+ "mr %%r19, %[len]\n\t"
+ "mr %%r20, %[src]\n\t"
+ "mr %%r21, %[dst]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+#endif
+ /* try memcpy */
+ RSEQ_ASM_OP_R_MEMCPY()
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17", "r18", "r19", "r20", "r21"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* setup for mempcy */
+ "mr %%r19, %[len]\n\t"
+ "mr %%r20, %[src]\n\t"
+ "mr %%r21, %[dst]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[cmpfail])
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ /* cmp cpuid */
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ /* cmp @v equal to @expect */
+ RSEQ_ASM_OP_CMPEQ(v, expect, %l[error2])
+#endif
+ /* try memcpy */
+ RSEQ_ASM_OP_R_MEMCPY()
+ RSEQ_INJECT_ASM(5)
+ /* for 'release' */
+ "lwsync\n\t"
+ /* final store */
+ RSEQ_ASM_OP_FINAL_STORE(newv, v, 2)
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ RSEQ_ASM_DEFINE_ABORT(4, abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len)
+ RSEQ_INJECT_INPUT
+ : "memory", "cc", "r17", "r18", "r19", "r20", "r21"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+#undef STORE_WORD
+#undef LOAD_WORD
+#undef LOADX_WORD
+#undef CMP_WORD
+
+#endif /* !RSEQ_SKIP_FASTPATH */
diff --git a/tools/testing/selftests/rseq/rseq-skip.h b/tools/testing/selftests/rseq/rseq-skip.h
new file mode 100644
index 000000000000..72750b5905a9
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq-skip.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * rseq-skip.h
+ *
+ * (C) Copyright 2017-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
+ off_t voffp, intptr_t *load, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_addv(intptr_t *v, intptr_t count, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t expect2,
+ intptr_t newv, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ return -1;
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ return -1;
+}
diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h
new file mode 100644
index 000000000000..089410a314e9
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq-x86.h
@@ -0,0 +1,1132 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * rseq-x86.h
+ *
+ * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#include <stdint.h>
+
+#define RSEQ_SIG 0x53053053
+
+#ifdef __x86_64__
+
+#define rseq_smp_mb() \
+ __asm__ __volatile__ ("lock; addl $0,-128(%%rsp)" ::: "memory", "cc")
+#define rseq_smp_rmb() rseq_barrier()
+#define rseq_smp_wmb() rseq_barrier()
+
+#define rseq_smp_load_acquire(p) \
+__extension__ ({ \
+ __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
+ rseq_barrier(); \
+ ____p1; \
+})
+
+#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb()
+
+#define rseq_smp_store_release(p, v) \
+do { \
+ rseq_barrier(); \
+ RSEQ_WRITE_ONCE(*p, v); \
+} while (0)
+
+#ifdef RSEQ_SKIP_FASTPATH
+#include "rseq-skip.h"
+#else /* !RSEQ_SKIP_FASTPATH */
+
+#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \
+ start_ip, post_commit_offset, abort_ip) \
+ ".pushsection __rseq_table, \"aw\"\n\t" \
+ ".balign 32\n\t" \
+ __rseq_str(label) ":\n\t" \
+ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
+ __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
+ (post_commit_ip - start_ip), abort_ip)
+
+#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
+ RSEQ_INJECT_ASM(1) \
+ "leaq " __rseq_str(cs_label) "(%%rip), %%rax\n\t" \
+ "movq %%rax, %[" __rseq_str(rseq_cs) "]\n\t" \
+ __rseq_str(label) ":\n\t"
+
+#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
+ RSEQ_INJECT_ASM(2) \
+ "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "jnz " __rseq_str(label) "\n\t"
+
+#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \
+ ".pushsection __rseq_failure, \"ax\"\n\t" \
+ /* Disassembler-friendly signature: nopl <sig>(%rip). */\
+ ".byte 0x0f, 0x1f, 0x05\n\t" \
+ ".long " __rseq_str(RSEQ_SIG) "\n\t" \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "jmp %l[" __rseq_str(abort_label) "]\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
+ ".pushsection __rseq_failure, \"ax\"\n\t" \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \
+ ".popsection\n\t"
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+#endif
+ /* final store */
+ "movq %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "rax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+/*
+ * Compare @v against @expectnot. When it does _not_ match, load @v
+ * into @load, and store the content of *@v + voffp into @v.
+ */
+static inline __attribute__((always_inline))
+int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
+ off_t voffp, intptr_t *load, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "movq %[v], %%rbx\n\t"
+ "cmpq %%rbx, %[expectnot]\n\t"
+ "je %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "movq %[v], %%rbx\n\t"
+ "cmpq %%rbx, %[expectnot]\n\t"
+ "je %l[error2]\n\t"
+#endif
+ "movq %%rbx, %[load]\n\t"
+ "addq %[voffp], %%rbx\n\t"
+ "movq (%%rbx), %%rbx\n\t"
+ /* final store */
+ "movq %%rbx, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expectnot] "r" (expectnot),
+ [voffp] "er" (voffp),
+ [load] "m" (*load)
+ : "memory", "cc", "rax", "rbx"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_addv(intptr_t *v, intptr_t count, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+#endif
+ /* final store */
+ "addq %[count], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(4)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [count] "er" (count)
+ : "memory", "cc", "rax"
+ RSEQ_INJECT_CLOBBER
+ : abort
+#ifdef RSEQ_COMPARE_TWICE
+ , error1
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+#endif
+ /* try store */
+ "movq %[newv2], %[v2]\n\t"
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ "movq %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "rax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+/* x86-64 is TSO. */
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ return rseq_cmpeqv_trystorev_storev(v, expect, v2, newv2, newv, cpu);
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t expect2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+ "cmpq %[v2], %[expect2]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(5)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpq %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+ "cmpq %[v2], %[expect2]\n\t"
+ "jnz %l[error3]\n\t"
+#endif
+ /* final store */
+ "movq %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* cmp2 input */
+ [v2] "m" (*v2),
+ [expect2] "r" (expect2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "rax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2, error3
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("1st expected value comparison failed");
+error3:
+ rseq_bug("2nd expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ uint64_t rseq_scratch[3];
+
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ "movq %[src], %[rseq_scratch0]\n\t"
+ "movq %[dst], %[rseq_scratch1]\n\t"
+ "movq %[len], %[rseq_scratch2]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpq %[v], %[expect]\n\t"
+ "jnz 5f\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ "cmpq %[v], %[expect]\n\t"
+ "jnz 7f\n\t"
+#endif
+ /* try memcpy */
+ "test %[len], %[len]\n\t" \
+ "jz 333f\n\t" \
+ "222:\n\t" \
+ "movb (%[src]), %%al\n\t" \
+ "movb %%al, (%[dst])\n\t" \
+ "inc %[src]\n\t" \
+ "inc %[dst]\n\t" \
+ "dec %[len]\n\t" \
+ "jnz 222b\n\t" \
+ "333:\n\t" \
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ "movq %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ "movq %[rseq_scratch2], %[len]\n\t"
+ "movq %[rseq_scratch1], %[dst]\n\t"
+ "movq %[rseq_scratch0], %[src]\n\t"
+ RSEQ_ASM_DEFINE_ABORT(4,
+ "movq %[rseq_scratch2], %[len]\n\t"
+ "movq %[rseq_scratch1], %[dst]\n\t"
+ "movq %[rseq_scratch0], %[src]\n\t",
+ abort)
+ RSEQ_ASM_DEFINE_CMPFAIL(5,
+ "movq %[rseq_scratch2], %[len]\n\t"
+ "movq %[rseq_scratch1], %[dst]\n\t"
+ "movq %[rseq_scratch0], %[src]\n\t",
+ cmpfail)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_DEFINE_CMPFAIL(6,
+ "movq %[rseq_scratch2], %[len]\n\t"
+ "movq %[rseq_scratch1], %[dst]\n\t"
+ "movq %[rseq_scratch0], %[src]\n\t",
+ error1)
+ RSEQ_ASM_DEFINE_CMPFAIL(7,
+ "movq %[rseq_scratch2], %[len]\n\t"
+ "movq %[rseq_scratch1], %[dst]\n\t"
+ "movq %[rseq_scratch0], %[src]\n\t",
+ error2)
+#endif
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len),
+ [rseq_scratch0] "m" (rseq_scratch[0]),
+ [rseq_scratch1] "m" (rseq_scratch[1]),
+ [rseq_scratch2] "m" (rseq_scratch[2])
+ : "memory", "cc", "rax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+/* x86-64 is TSO. */
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ return rseq_cmpeqv_trymemcpy_storev(v, expect, dst, src, len,
+ newv, cpu);
+}
+
+#endif /* !RSEQ_SKIP_FASTPATH */
+
+#elif __i386__
+
+#define rseq_smp_mb() \
+ __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc")
+#define rseq_smp_rmb() \
+ __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc")
+#define rseq_smp_wmb() \
+ __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc")
+
+#define rseq_smp_load_acquire(p) \
+__extension__ ({ \
+ __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
+ rseq_smp_mb(); \
+ ____p1; \
+})
+
+#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb()
+
+#define rseq_smp_store_release(p, v) \
+do { \
+ rseq_smp_mb(); \
+ RSEQ_WRITE_ONCE(*p, v); \
+} while (0)
+
+#ifdef RSEQ_SKIP_FASTPATH
+#include "rseq-skip.h"
+#else /* !RSEQ_SKIP_FASTPATH */
+
+/*
+ * Use eax as scratch register and take memory operands as input to
+ * lessen register pressure. Especially needed when compiling in O0.
+ */
+#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \
+ start_ip, post_commit_offset, abort_ip) \
+ ".pushsection __rseq_table, \"aw\"\n\t" \
+ ".balign 32\n\t" \
+ __rseq_str(label) ":\n\t" \
+ ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
+ ".long " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
+ __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
+ (post_commit_ip - start_ip), abort_ip)
+
+#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
+ RSEQ_INJECT_ASM(1) \
+ "movl $" __rseq_str(cs_label) ", %[rseq_cs]\n\t" \
+ __rseq_str(label) ":\n\t"
+
+#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
+ RSEQ_INJECT_ASM(2) \
+ "cmpl %[" __rseq_str(cpu_id) "], %[" __rseq_str(current_cpu_id) "]\n\t" \
+ "jnz " __rseq_str(label) "\n\t"
+
+#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \
+ ".pushsection __rseq_failure, \"ax\"\n\t" \
+ /* Disassembler-friendly signature: nopl <sig>. */ \
+ ".byte 0x0f, 0x1f, 0x05\n\t" \
+ ".long " __rseq_str(RSEQ_SIG) "\n\t" \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "jmp %l[" __rseq_str(abort_label) "]\n\t" \
+ ".popsection\n\t"
+
+#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
+ ".pushsection __rseq_failure, \"ax\"\n\t" \
+ __rseq_str(label) ":\n\t" \
+ teardown \
+ "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \
+ ".popsection\n\t"
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+#endif
+ /* final store */
+ "movl %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+/*
+ * Compare @v against @expectnot. When it does _not_ match, load @v
+ * into @load, and store the content of *@v + voffp into @v.
+ */
+static inline __attribute__((always_inline))
+int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
+ off_t voffp, intptr_t *load, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "movl %[v], %%ebx\n\t"
+ "cmpl %%ebx, %[expectnot]\n\t"
+ "je %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "movl %[v], %%ebx\n\t"
+ "cmpl %%ebx, %[expectnot]\n\t"
+ "je %l[error2]\n\t"
+#endif
+ "movl %%ebx, %[load]\n\t"
+ "addl %[voffp], %%ebx\n\t"
+ "movl (%%ebx), %%ebx\n\t"
+ /* final store */
+ "movl %%ebx, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(5)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expectnot] "r" (expectnot),
+ [voffp] "ir" (voffp),
+ [load] "m" (*load)
+ : "memory", "cc", "eax", "ebx"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_addv(intptr_t *v, intptr_t count, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+#endif
+ /* final store */
+ "addl %[count], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(4)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [count] "ir" (count)
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort
+#ifdef RSEQ_COMPARE_TWICE
+ , error1
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+#endif
+ /* try store */
+ "movl %[newv2], %%eax\n\t"
+ "movl %%eax, %[v2]\n\t"
+ RSEQ_INJECT_ASM(5)
+ /* final store */
+ "movl %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "m" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t newv2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "movl %[expect], %%eax\n\t"
+ "cmpl %[v], %%eax\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "movl %[expect], %%eax\n\t"
+ "cmpl %[v], %%eax\n\t"
+ "jnz %l[error2]\n\t"
+#endif
+ /* try store */
+ "movl %[newv2], %[v2]\n\t"
+ RSEQ_INJECT_ASM(5)
+ "lock; addl $0,-128(%%esp)\n\t"
+ /* final store */
+ "movl %[newv], %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* try store input */
+ [v2] "m" (*v2),
+ [newv2] "r" (newv2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "m" (expect),
+ [newv] "r" (newv)
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+
+}
+
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
+ intptr_t *v2, intptr_t expect2,
+ intptr_t newv, int cpu)
+{
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(4)
+ "cmpl %[expect2], %[v2]\n\t"
+ "jnz %l[cmpfail]\n\t"
+ RSEQ_INJECT_ASM(5)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
+ "cmpl %[v], %[expect]\n\t"
+ "jnz %l[error2]\n\t"
+ "cmpl %[expect2], %[v2]\n\t"
+ "jnz %l[error3]\n\t"
+#endif
+ "movl %[newv], %%eax\n\t"
+ /* final store */
+ "movl %%eax, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ RSEQ_ASM_DEFINE_ABORT(4, "", abort)
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* cmp2 input */
+ [v2] "m" (*v2),
+ [expect2] "r" (expect2),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "r" (expect),
+ [newv] "m" (newv)
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2, error3
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("1st expected value comparison failed");
+error3:
+ rseq_bug("2nd expected value comparison failed");
+#endif
+}
+
+/* TODO: implement a faster memcpy. */
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ uint32_t rseq_scratch[3];
+
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ "movl %[src], %[rseq_scratch0]\n\t"
+ "movl %[dst], %[rseq_scratch1]\n\t"
+ "movl %[len], %[rseq_scratch2]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "movl %[expect], %%eax\n\t"
+ "cmpl %%eax, %[v]\n\t"
+ "jnz 5f\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ "movl %[expect], %%eax\n\t"
+ "cmpl %%eax, %[v]\n\t"
+ "jnz 7f\n\t"
+#endif
+ /* try memcpy */
+ "test %[len], %[len]\n\t" \
+ "jz 333f\n\t" \
+ "222:\n\t" \
+ "movb (%[src]), %%al\n\t" \
+ "movb %%al, (%[dst])\n\t" \
+ "inc %[src]\n\t" \
+ "inc %[dst]\n\t" \
+ "dec %[len]\n\t" \
+ "jnz 222b\n\t" \
+ "333:\n\t" \
+ RSEQ_INJECT_ASM(5)
+ "movl %[newv], %%eax\n\t"
+ /* final store */
+ "movl %%eax, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t"
+ RSEQ_ASM_DEFINE_ABORT(4,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ abort)
+ RSEQ_ASM_DEFINE_CMPFAIL(5,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ cmpfail)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_DEFINE_CMPFAIL(6,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ error1)
+ RSEQ_ASM_DEFINE_CMPFAIL(7,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ error2)
+#endif
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "m" (expect),
+ [newv] "m" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len),
+ [rseq_scratch0] "m" (rseq_scratch[0]),
+ [rseq_scratch1] "m" (rseq_scratch[1]),
+ [rseq_scratch2] "m" (rseq_scratch[2])
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+/* TODO: implement a faster memcpy. */
+static inline __attribute__((always_inline))
+int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
+ void *dst, void *src, size_t len,
+ intptr_t newv, int cpu)
+{
+ uint32_t rseq_scratch[3];
+
+ RSEQ_INJECT_C(9)
+
+ __asm__ __volatile__ goto (
+ RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */
+ "movl %[src], %[rseq_scratch0]\n\t"
+ "movl %[dst], %[rseq_scratch1]\n\t"
+ "movl %[len], %[rseq_scratch2]\n\t"
+ /* Start rseq by storing table entry pointer into rseq_cs. */
+ RSEQ_ASM_STORE_RSEQ_CS(1, 3b, rseq_cs)
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
+ RSEQ_INJECT_ASM(3)
+ "movl %[expect], %%eax\n\t"
+ "cmpl %%eax, %[v]\n\t"
+ "jnz 5f\n\t"
+ RSEQ_INJECT_ASM(4)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
+ "movl %[expect], %%eax\n\t"
+ "cmpl %%eax, %[v]\n\t"
+ "jnz 7f\n\t"
+#endif
+ /* try memcpy */
+ "test %[len], %[len]\n\t" \
+ "jz 333f\n\t" \
+ "222:\n\t" \
+ "movb (%[src]), %%al\n\t" \
+ "movb %%al, (%[dst])\n\t" \
+ "inc %[src]\n\t" \
+ "inc %[dst]\n\t" \
+ "dec %[len]\n\t" \
+ "jnz 222b\n\t" \
+ "333:\n\t" \
+ RSEQ_INJECT_ASM(5)
+ "lock; addl $0,-128(%%esp)\n\t"
+ "movl %[newv], %%eax\n\t"
+ /* final store */
+ "movl %%eax, %[v]\n\t"
+ "2:\n\t"
+ RSEQ_INJECT_ASM(6)
+ /* teardown */
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t"
+ RSEQ_ASM_DEFINE_ABORT(4,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ abort)
+ RSEQ_ASM_DEFINE_CMPFAIL(5,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ cmpfail)
+#ifdef RSEQ_COMPARE_TWICE
+ RSEQ_ASM_DEFINE_CMPFAIL(6,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ error1)
+ RSEQ_ASM_DEFINE_CMPFAIL(7,
+ "movl %[rseq_scratch2], %[len]\n\t"
+ "movl %[rseq_scratch1], %[dst]\n\t"
+ "movl %[rseq_scratch0], %[src]\n\t",
+ error2)
+#endif
+ : /* gcc asm goto does not allow outputs */
+ : [cpu_id] "r" (cpu),
+ [current_cpu_id] "m" (__rseq_abi.cpu_id),
+ [rseq_cs] "m" (__rseq_abi.rseq_cs),
+ /* final store input */
+ [v] "m" (*v),
+ [expect] "m" (expect),
+ [newv] "m" (newv),
+ /* try memcpy input */
+ [dst] "r" (dst),
+ [src] "r" (src),
+ [len] "r" (len),
+ [rseq_scratch0] "m" (rseq_scratch[0]),
+ [rseq_scratch1] "m" (rseq_scratch[1]),
+ [rseq_scratch2] "m" (rseq_scratch[2])
+ : "memory", "cc", "eax"
+ RSEQ_INJECT_CLOBBER
+ : abort, cmpfail
+#ifdef RSEQ_COMPARE_TWICE
+ , error1, error2
+#endif
+ );
+ return 0;
+abort:
+ RSEQ_INJECT_FAILED
+ return -1;
+cmpfail:
+ return 1;
+#ifdef RSEQ_COMPARE_TWICE
+error1:
+ rseq_bug("cpu_id comparison failed");
+error2:
+ rseq_bug("expected value comparison failed");
+#endif
+}
+
+#endif /* !RSEQ_SKIP_FASTPATH */
+
+#endif
diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c
new file mode 100644
index 000000000000..4847e97ed049
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * rseq.c
+ *
+ * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <assert.h>
+#include <signal.h>
+
+#include "rseq.h"
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+__attribute__((tls_model("initial-exec"))) __thread
+volatile struct rseq __rseq_abi = {
+ .cpu_id = RSEQ_CPU_ID_UNINITIALIZED,
+};
+
+static __attribute__((tls_model("initial-exec"))) __thread
+volatile int refcount;
+
+static void signal_off_save(sigset_t *oldset)
+{
+ sigset_t set;
+ int ret;
+
+ sigfillset(&set);
+ ret = pthread_sigmask(SIG_BLOCK, &set, oldset);
+ if (ret)
+ abort();
+}
+
+static void signal_restore(sigset_t oldset)
+{
+ int ret;
+
+ ret = pthread_sigmask(SIG_SETMASK, &oldset, NULL);
+ if (ret)
+ abort();
+}
+
+static int sys_rseq(volatile struct rseq *rseq_abi, uint32_t rseq_len,
+ int flags, uint32_t sig)
+{
+ return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig);
+}
+
+int rseq_register_current_thread(void)
+{
+ int rc, ret = 0;
+ sigset_t oldset;
+
+ signal_off_save(&oldset);
+ if (refcount++)
+ goto end;
+ rc = sys_rseq(&__rseq_abi, sizeof(struct rseq), 0, RSEQ_SIG);
+ if (!rc) {
+ assert(rseq_current_cpu_raw() >= 0);
+ goto end;
+ }
+ if (errno != EBUSY)
+ __rseq_abi.cpu_id = -2;
+ ret = -1;
+ refcount--;
+end:
+ signal_restore(oldset);
+ return ret;
+}
+
+int rseq_unregister_current_thread(void)
+{
+ int rc, ret = 0;
+ sigset_t oldset;
+
+ signal_off_save(&oldset);
+ if (--refcount)
+ goto end;
+ rc = sys_rseq(&__rseq_abi, sizeof(struct rseq),
+ RSEQ_FLAG_UNREGISTER, RSEQ_SIG);
+ if (!rc)
+ goto end;
+ ret = -1;
+end:
+ signal_restore(oldset);
+ return ret;
+}
+
+int32_t rseq_fallback_current_cpu(void)
+{
+ int32_t cpu;
+
+ cpu = sched_getcpu();
+ if (cpu < 0) {
+ perror("sched_getcpu()");
+ abort();
+ }
+ return cpu;
+}
diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h
new file mode 100644
index 000000000000..0a808575cbc4
--- /dev/null
+++ b/tools/testing/selftests/rseq/rseq.h
@@ -0,0 +1,147 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * rseq.h
+ *
+ * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ */
+
+#ifndef RSEQ_H
+#define RSEQ_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <pthread.h>
+#include <signal.h>
+#include <sched.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sched.h>
+#include <linux/rseq.h>
+
+/*
+ * Empty code injection macros, override when testing.
+ * It is important to consider that the ASM injection macros need to be
+ * fully reentrant (e.g. do not modify the stack).
+ */
+#ifndef RSEQ_INJECT_ASM
+#define RSEQ_INJECT_ASM(n)
+#endif
+
+#ifndef RSEQ_INJECT_C
+#define RSEQ_INJECT_C(n)
+#endif
+
+#ifndef RSEQ_INJECT_INPUT
+#define RSEQ_INJECT_INPUT
+#endif
+
+#ifndef RSEQ_INJECT_CLOBBER
+#define RSEQ_INJECT_CLOBBER
+#endif
+
+#ifndef RSEQ_INJECT_FAILED
+#define RSEQ_INJECT_FAILED
+#endif
+
+extern __thread volatile struct rseq __rseq_abi;
+
+#define rseq_likely(x) __builtin_expect(!!(x), 1)
+#define rseq_unlikely(x) __builtin_expect(!!(x), 0)
+#define rseq_barrier() __asm__ __volatile__("" : : : "memory")
+
+#define RSEQ_ACCESS_ONCE(x) (*(__volatile__ __typeof__(x) *)&(x))
+#define RSEQ_WRITE_ONCE(x, v) __extension__ ({ RSEQ_ACCESS_ONCE(x) = (v); })
+#define RSEQ_READ_ONCE(x) RSEQ_ACCESS_ONCE(x)
+
+#define __rseq_str_1(x) #x
+#define __rseq_str(x) __rseq_str_1(x)
+
+#define rseq_log(fmt, args...) \
+ fprintf(stderr, fmt "(in %s() at " __FILE__ ":" __rseq_str(__LINE__)"\n", \
+ ## args, __func__)
+
+#define rseq_bug(fmt, args...) \
+ do { \
+ rseq_log(fmt, ##args); \
+ abort(); \
+ } while (0)
+
+#if defined(__x86_64__) || defined(__i386__)
+#include <rseq-x86.h>
+#elif defined(__ARMEL__)
+#include <rseq-arm.h>
+#elif defined(__PPC__)
+#include <rseq-ppc.h>
+#else
+#error unsupported target
+#endif
+
+/*
+ * Register rseq for the current thread. This needs to be called once
+ * by any thread which uses restartable sequences, before they start
+ * using restartable sequences, to ensure restartable sequences
+ * succeed. A restartable sequence executed from a non-registered
+ * thread will always fail.
+ */
+int rseq_register_current_thread(void);
+
+/*
+ * Unregister rseq for current thread.
+ */
+int rseq_unregister_current_thread(void);
+
+/*
+ * Restartable sequence fallback for reading the current CPU number.
+ */
+int32_t rseq_fallback_current_cpu(void);
+
+/*
+ * Values returned can be either the current CPU number, -1 (rseq is
+ * uninitialized), or -2 (rseq initialization has failed).
+ */
+static inline int32_t rseq_current_cpu_raw(void)
+{
+ return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id);
+}
+
+/*
+ * Returns a possible CPU number, which is typically the current CPU.
+ * The returned CPU number can be used to prepare for an rseq critical
+ * section, which will confirm whether the cpu number is indeed the
+ * current one, and whether rseq is initialized.
+ *
+ * The CPU number returned by rseq_cpu_start should always be validated
+ * by passing it to a rseq asm sequence, or by comparing it to the
+ * return value of rseq_current_cpu_raw() if the rseq asm sequence
+ * does not need to be invoked.
+ */
+static inline uint32_t rseq_cpu_start(void)
+{
+ return RSEQ_ACCESS_ONCE(__rseq_abi.cpu_id_start);
+}
+
+static inline uint32_t rseq_current_cpu(void)
+{
+ int32_t cpu;
+
+ cpu = rseq_current_cpu_raw();
+ if (rseq_unlikely(cpu < 0))
+ cpu = rseq_fallback_current_cpu();
+ return cpu;
+}
+
+/*
+ * rseq_prepare_unload() should be invoked by each thread using rseq_finish*()
+ * at least once between their last rseq_finish*() and library unload of the
+ * library defining the rseq critical section (struct rseq_cs). This also
+ * applies to use of rseq in code generated by JIT: rseq_prepare_unload()
+ * should be invoked at least once by each thread using rseq_finish*() before
+ * reclaim of the memory holding the struct rseq_cs.
+ */
+static inline void rseq_prepare_unload(void)
+{
+ __rseq_abi.rseq_cs = 0;
+}
+
+#endif /* RSEQ_H_ */
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 13/16] rseq: selftests: Provide basic test
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers, Shuah Khan
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
"basic_test" only asserts that RSEQ works moderately correctly. E.g.
that the CPUID pointer works.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
tools/testing/selftests/rseq/basic_test.c | 56 +++++++++++++++++++++++++++++++
1 file changed, 56 insertions(+)
create mode 100644 tools/testing/selftests/rseq/basic_test.c
diff --git a/tools/testing/selftests/rseq/basic_test.c b/tools/testing/selftests/rseq/basic_test.c
new file mode 100644
index 000000000000..d8efbfb89193
--- /dev/null
+++ b/tools/testing/selftests/rseq/basic_test.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Basic test coverage for critical regions and rseq_current_cpu().
+ */
+
+#define _GNU_SOURCE
+#include <assert.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+
+#include "rseq.h"
+
+void test_cpu_pointer(void)
+{
+ cpu_set_t affinity, test_affinity;
+ int i;
+
+ sched_getaffinity(0, sizeof(affinity), &affinity);
+ CPU_ZERO(&test_affinity);
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (CPU_ISSET(i, &affinity)) {
+ CPU_SET(i, &test_affinity);
+ sched_setaffinity(0, sizeof(test_affinity),
+ &test_affinity);
+ assert(sched_getcpu() == i);
+ assert(rseq_current_cpu() == i);
+ assert(rseq_current_cpu_raw() == i);
+ assert(rseq_cpu_start() == i);
+ CPU_CLR(i, &test_affinity);
+ }
+ }
+ sched_setaffinity(0, sizeof(affinity), &affinity);
+}
+
+int main(int argc, char **argv)
+{
+ if (rseq_register_current_thread()) {
+ fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ goto init_thread_error;
+ }
+ printf("testing current cpu\n");
+ test_cpu_pointer();
+ if (rseq_unregister_current_thread()) {
+ fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ goto init_thread_error;
+ }
+ return 0;
+
+init_thread_error:
+ return -1;
+}
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 14/16] rseq: selftests: Provide basic percpu ops test (v2)
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers, Shuah Khan
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
"basic_percpu_ops_test" is a slightly more "realistic" variant,
implementing a few simple per-cpu operations and testing their
correctness.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
Changes since v1:
- Use only rseq, remove use of cpu_opv system call.
---
.../testing/selftests/rseq/basic_percpu_ops_test.c | 313 +++++++++++++++++++++
1 file changed, 313 insertions(+)
create mode 100644 tools/testing/selftests/rseq/basic_percpu_ops_test.c
diff --git a/tools/testing/selftests/rseq/basic_percpu_ops_test.c b/tools/testing/selftests/rseq/basic_percpu_ops_test.c
new file mode 100644
index 000000000000..96ef27905879
--- /dev/null
+++ b/tools/testing/selftests/rseq/basic_percpu_ops_test.c
@@ -0,0 +1,313 @@
+// SPDX-License-Identifier: LGPL-2.1
+#define _GNU_SOURCE
+#include <assert.h>
+#include <pthread.h>
+#include <sched.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stddef.h>
+
+#include "rseq.h"
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+struct percpu_lock_entry {
+ intptr_t v;
+} __attribute__((aligned(128)));
+
+struct percpu_lock {
+ struct percpu_lock_entry c[CPU_SETSIZE];
+};
+
+struct test_data_entry {
+ intptr_t count;
+} __attribute__((aligned(128)));
+
+struct spinlock_test_data {
+ struct percpu_lock lock;
+ struct test_data_entry c[CPU_SETSIZE];
+ int reps;
+};
+
+struct percpu_list_node {
+ intptr_t data;
+ struct percpu_list_node *next;
+};
+
+struct percpu_list_entry {
+ struct percpu_list_node *head;
+} __attribute__((aligned(128)));
+
+struct percpu_list {
+ struct percpu_list_entry c[CPU_SETSIZE];
+};
+
+/* A simple percpu spinlock. Returns the cpu lock was acquired on. */
+int rseq_this_cpu_lock(struct percpu_lock *lock)
+{
+ int cpu;
+
+ for (;;) {
+ int ret;
+
+ cpu = rseq_cpu_start();
+ ret = rseq_cmpeqv_storev(&lock->c[cpu].v,
+ 0, 1, cpu);
+ if (rseq_likely(!ret))
+ break;
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ /*
+ * Acquire semantic when taking lock after control dependency.
+ * Matches rseq_smp_store_release().
+ */
+ rseq_smp_acquire__after_ctrl_dep();
+ return cpu;
+}
+
+void rseq_percpu_unlock(struct percpu_lock *lock, int cpu)
+{
+ assert(lock->c[cpu].v == 1);
+ /*
+ * Release lock, with release semantic. Matches
+ * rseq_smp_acquire__after_ctrl_dep().
+ */
+ rseq_smp_store_release(&lock->c[cpu].v, 0);
+}
+
+void *test_percpu_spinlock_thread(void *arg)
+{
+ struct spinlock_test_data *data = arg;
+ int i, cpu;
+
+ if (rseq_register_current_thread()) {
+ fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ abort();
+ }
+ for (i = 0; i < data->reps; i++) {
+ cpu = rseq_this_cpu_lock(&data->lock);
+ data->c[cpu].count++;
+ rseq_percpu_unlock(&data->lock, cpu);
+ }
+ if (rseq_unregister_current_thread()) {
+ fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ abort();
+ }
+
+ return NULL;
+}
+
+/*
+ * A simple test which implements a sharded counter using a per-cpu
+ * lock. Obviously real applications might prefer to simply use a
+ * per-cpu increment; however, this is reasonable for a test and the
+ * lock can be extended to synchronize more complicated operations.
+ */
+void test_percpu_spinlock(void)
+{
+ const int num_threads = 200;
+ int i;
+ uint64_t sum;
+ pthread_t test_threads[num_threads];
+ struct spinlock_test_data data;
+
+ memset(&data, 0, sizeof(data));
+ data.reps = 5000;
+
+ for (i = 0; i < num_threads; i++)
+ pthread_create(&test_threads[i], NULL,
+ test_percpu_spinlock_thread, &data);
+
+ for (i = 0; i < num_threads; i++)
+ pthread_join(test_threads[i], NULL);
+
+ sum = 0;
+ for (i = 0; i < CPU_SETSIZE; i++)
+ sum += data.c[i].count;
+
+ assert(sum == (uint64_t)data.reps * num_threads);
+}
+
+void this_cpu_list_push(struct percpu_list *list,
+ struct percpu_list_node *node,
+ int *_cpu)
+{
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr, newval, expect;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ /* Load list->c[cpu].head with single-copy atomicity. */
+ expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head);
+ newval = (intptr_t)node;
+ targetptr = (intptr_t *)&list->c[cpu].head;
+ node->next = (struct percpu_list_node *)expect;
+ ret = rseq_cmpeqv_storev(targetptr, expect, newval, cpu);
+ if (rseq_likely(!ret))
+ break;
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+}
+
+/*
+ * Unlike a traditional lock-less linked list; the availability of a
+ * rseq primitive allows us to implement pop without concerns over
+ * ABA-type races.
+ */
+struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list,
+ int *_cpu)
+{
+ for (;;) {
+ struct percpu_list_node *head;
+ intptr_t *targetptr, expectnot, *load;
+ off_t offset;
+ int ret, cpu;
+
+ cpu = rseq_cpu_start();
+ targetptr = (intptr_t *)&list->c[cpu].head;
+ expectnot = (intptr_t)NULL;
+ offset = offsetof(struct percpu_list_node, next);
+ load = (intptr_t *)&head;
+ ret = rseq_cmpnev_storeoffp_load(targetptr, expectnot,
+ offset, load, cpu);
+ if (rseq_likely(!ret)) {
+ if (_cpu)
+ *_cpu = cpu;
+ return head;
+ }
+ if (ret > 0)
+ return NULL;
+ /* Retry if rseq aborts. */
+ }
+}
+
+/*
+ * __percpu_list_pop is not safe against concurrent accesses. Should
+ * only be used on lists that are not concurrently modified.
+ */
+struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu)
+{
+ struct percpu_list_node *node;
+
+ node = list->c[cpu].head;
+ if (!node)
+ return NULL;
+ list->c[cpu].head = node->next;
+ return node;
+}
+
+void *test_percpu_list_thread(void *arg)
+{
+ int i;
+ struct percpu_list *list = (struct percpu_list *)arg;
+
+ if (rseq_register_current_thread()) {
+ fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ abort();
+ }
+
+ for (i = 0; i < 100000; i++) {
+ struct percpu_list_node *node;
+
+ node = this_cpu_list_pop(list, NULL);
+ sched_yield(); /* encourage shuffling */
+ if (node)
+ this_cpu_list_push(list, node, NULL);
+ }
+
+ if (rseq_unregister_current_thread()) {
+ fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ abort();
+ }
+
+ return NULL;
+}
+
+/* Simultaneous modification to a per-cpu linked list from many threads. */
+void test_percpu_list(void)
+{
+ int i, j;
+ uint64_t sum = 0, expected_sum = 0;
+ struct percpu_list list;
+ pthread_t test_threads[200];
+ cpu_set_t allowed_cpus;
+
+ memset(&list, 0, sizeof(list));
+
+ /* Generate list entries for every usable cpu. */
+ sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+ for (j = 1; j <= 100; j++) {
+ struct percpu_list_node *node;
+
+ expected_sum += j;
+
+ node = malloc(sizeof(*node));
+ assert(node);
+ node->data = j;
+ node->next = list.c[i].head;
+ list.c[i].head = node;
+ }
+ }
+
+ for (i = 0; i < 200; i++)
+ pthread_create(&test_threads[i], NULL,
+ test_percpu_list_thread, &list);
+
+ for (i = 0; i < 200; i++)
+ pthread_join(test_threads[i], NULL);
+
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ struct percpu_list_node *node;
+
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+
+ while ((node = __percpu_list_pop(&list, i))) {
+ sum += node->data;
+ free(node);
+ }
+ }
+
+ /*
+ * All entries should now be accounted for (unless some external
+ * actor is interfering with our allowed affinity while this
+ * test is running).
+ */
+ assert(sum == expected_sum);
+}
+
+int main(int argc, char **argv)
+{
+ if (rseq_register_current_thread()) {
+ fprintf(stderr, "Error: rseq_register_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ goto error;
+ }
+ printf("spinlock\n");
+ test_percpu_spinlock();
+ printf("percpu_list\n");
+ test_percpu_list();
+ if (rseq_unregister_current_thread()) {
+ fprintf(stderr, "Error: rseq_unregister_current_thread(...) failed(%d): %s\n",
+ errno, strerror(errno));
+ goto error;
+ }
+ return 0;
+
+error:
+ return -1;
+}
+
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 15/16] rseq: selftests: Provide parametrized tests (v2)
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers, Shuah Khan
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
"param_test" is a parametrizable restartable sequences test. See
the "--help" output for usage.
"param_test_benchmark" is the same as "param_test", but it removes
testing book-keeping code to allow accurate benchmarks.
"param_test_compare_twice" is the same as "param_test", but it performs
each comparison within rseq critical section twice, thus validating
invariants. If any of the second comparisons fails, an error message
is printed and the test aborts.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
Changes since v1:
- Use only rseq, remove use of cpu_opv.
---
tools/testing/selftests/rseq/param_test.c | 1260 +++++++++++++++++++++++++++++
1 file changed, 1260 insertions(+)
create mode 100644 tools/testing/selftests/rseq/param_test.c
diff --git a/tools/testing/selftests/rseq/param_test.c b/tools/testing/selftests/rseq/param_test.c
new file mode 100644
index 000000000000..6a9f602a8718
--- /dev/null
+++ b/tools/testing/selftests/rseq/param_test.c
@@ -0,0 +1,1260 @@
+// SPDX-License-Identifier: LGPL-2.1
+#define _GNU_SOURCE
+#include <assert.h>
+#include <pthread.h>
+#include <sched.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syscall.h>
+#include <unistd.h>
+#include <poll.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <errno.h>
+#include <stddef.h>
+
+static inline pid_t gettid(void)
+{
+ return syscall(__NR_gettid);
+}
+
+#define NR_INJECT 9
+static int loop_cnt[NR_INJECT + 1];
+
+static int loop_cnt_1 asm("asm_loop_cnt_1") __attribute__((used));
+static int loop_cnt_2 asm("asm_loop_cnt_2") __attribute__((used));
+static int loop_cnt_3 asm("asm_loop_cnt_3") __attribute__((used));
+static int loop_cnt_4 asm("asm_loop_cnt_4") __attribute__((used));
+static int loop_cnt_5 asm("asm_loop_cnt_5") __attribute__((used));
+static int loop_cnt_6 asm("asm_loop_cnt_6") __attribute__((used));
+
+static int opt_modulo, verbose;
+
+static int opt_yield, opt_signal, opt_sleep,
+ opt_disable_rseq, opt_threads = 200,
+ opt_disable_mod = 0, opt_test = 's', opt_mb = 0;
+
+#ifndef RSEQ_SKIP_FASTPATH
+static long long opt_reps = 5000;
+#else
+static long long opt_reps = 100;
+#endif
+
+static __thread __attribute__((tls_model("initial-exec")))
+unsigned int signals_delivered;
+
+#ifndef BENCHMARK
+
+static __thread __attribute__((tls_model("initial-exec"), unused))
+unsigned int yield_mod_cnt, nr_abort;
+
+#define printf_verbose(fmt, ...) \
+ do { \
+ if (verbose) \
+ printf(fmt, ## __VA_ARGS__); \
+ } while (0)
+
+#if defined(__x86_64__) || defined(__i386__)
+
+#define INJECT_ASM_REG "eax"
+
+#define RSEQ_INJECT_CLOBBER \
+ , INJECT_ASM_REG
+
+#ifdef __i386__
+
+#define RSEQ_INJECT_ASM(n) \
+ "mov asm_loop_cnt_" #n ", %%" INJECT_ASM_REG "\n\t" \
+ "test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
+ "jz 333f\n\t" \
+ "222:\n\t" \
+ "dec %%" INJECT_ASM_REG "\n\t" \
+ "jnz 222b\n\t" \
+ "333:\n\t"
+
+#elif defined(__x86_64__)
+
+#define RSEQ_INJECT_ASM(n) \
+ "lea asm_loop_cnt_" #n "(%%rip), %%" INJECT_ASM_REG "\n\t" \
+ "mov (%%" INJECT_ASM_REG "), %%" INJECT_ASM_REG "\n\t" \
+ "test %%" INJECT_ASM_REG ",%%" INJECT_ASM_REG "\n\t" \
+ "jz 333f\n\t" \
+ "222:\n\t" \
+ "dec %%" INJECT_ASM_REG "\n\t" \
+ "jnz 222b\n\t" \
+ "333:\n\t"
+
+#else
+#error "Unsupported architecture"
+#endif
+
+#elif defined(__ARMEL__)
+
+#define RSEQ_INJECT_INPUT \
+ , [loop_cnt_1]"m"(loop_cnt[1]) \
+ , [loop_cnt_2]"m"(loop_cnt[2]) \
+ , [loop_cnt_3]"m"(loop_cnt[3]) \
+ , [loop_cnt_4]"m"(loop_cnt[4]) \
+ , [loop_cnt_5]"m"(loop_cnt[5]) \
+ , [loop_cnt_6]"m"(loop_cnt[6])
+
+#define INJECT_ASM_REG "r4"
+
+#define RSEQ_INJECT_CLOBBER \
+ , INJECT_ASM_REG
+
+#define RSEQ_INJECT_ASM(n) \
+ "ldr " INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
+ "cmp " INJECT_ASM_REG ", #0\n\t" \
+ "beq 333f\n\t" \
+ "222:\n\t" \
+ "subs " INJECT_ASM_REG ", #1\n\t" \
+ "bne 222b\n\t" \
+ "333:\n\t"
+
+#elif __PPC__
+
+#define RSEQ_INJECT_INPUT \
+ , [loop_cnt_1]"m"(loop_cnt[1]) \
+ , [loop_cnt_2]"m"(loop_cnt[2]) \
+ , [loop_cnt_3]"m"(loop_cnt[3]) \
+ , [loop_cnt_4]"m"(loop_cnt[4]) \
+ , [loop_cnt_5]"m"(loop_cnt[5]) \
+ , [loop_cnt_6]"m"(loop_cnt[6])
+
+#define INJECT_ASM_REG "r18"
+
+#define RSEQ_INJECT_CLOBBER \
+ , INJECT_ASM_REG
+
+#define RSEQ_INJECT_ASM(n) \
+ "lwz %%" INJECT_ASM_REG ", %[loop_cnt_" #n "]\n\t" \
+ "cmpwi %%" INJECT_ASM_REG ", 0\n\t" \
+ "beq 333f\n\t" \
+ "222:\n\t" \
+ "subic. %%" INJECT_ASM_REG ", %%" INJECT_ASM_REG ", 1\n\t" \
+ "bne 222b\n\t" \
+ "333:\n\t"
+#else
+#error unsupported target
+#endif
+
+#define RSEQ_INJECT_FAILED \
+ nr_abort++;
+
+#define RSEQ_INJECT_C(n) \
+{ \
+ int loc_i, loc_nr_loops = loop_cnt[n]; \
+ \
+ for (loc_i = 0; loc_i < loc_nr_loops; loc_i++) { \
+ rseq_barrier(); \
+ } \
+ if (loc_nr_loops == -1 && opt_modulo) { \
+ if (yield_mod_cnt == opt_modulo - 1) { \
+ if (opt_sleep > 0) \
+ poll(NULL, 0, opt_sleep); \
+ if (opt_yield) \
+ sched_yield(); \
+ if (opt_signal) \
+ raise(SIGUSR1); \
+ yield_mod_cnt = 0; \
+ } else { \
+ yield_mod_cnt++; \
+ } \
+ } \
+}
+
+#else
+
+#define printf_verbose(fmt, ...)
+
+#endif /* BENCHMARK */
+
+#include "rseq.h"
+
+struct percpu_lock_entry {
+ intptr_t v;
+} __attribute__((aligned(128)));
+
+struct percpu_lock {
+ struct percpu_lock_entry c[CPU_SETSIZE];
+};
+
+struct test_data_entry {
+ intptr_t count;
+} __attribute__((aligned(128)));
+
+struct spinlock_test_data {
+ struct percpu_lock lock;
+ struct test_data_entry c[CPU_SETSIZE];
+};
+
+struct spinlock_thread_test_data {
+ struct spinlock_test_data *data;
+ long long reps;
+ int reg;
+};
+
+struct inc_test_data {
+ struct test_data_entry c[CPU_SETSIZE];
+};
+
+struct inc_thread_test_data {
+ struct inc_test_data *data;
+ long long reps;
+ int reg;
+};
+
+struct percpu_list_node {
+ intptr_t data;
+ struct percpu_list_node *next;
+};
+
+struct percpu_list_entry {
+ struct percpu_list_node *head;
+} __attribute__((aligned(128)));
+
+struct percpu_list {
+ struct percpu_list_entry c[CPU_SETSIZE];
+};
+
+#define BUFFER_ITEM_PER_CPU 100
+
+struct percpu_buffer_node {
+ intptr_t data;
+};
+
+struct percpu_buffer_entry {
+ intptr_t offset;
+ intptr_t buflen;
+ struct percpu_buffer_node **array;
+} __attribute__((aligned(128)));
+
+struct percpu_buffer {
+ struct percpu_buffer_entry c[CPU_SETSIZE];
+};
+
+#define MEMCPY_BUFFER_ITEM_PER_CPU 100
+
+struct percpu_memcpy_buffer_node {
+ intptr_t data1;
+ uint64_t data2;
+};
+
+struct percpu_memcpy_buffer_entry {
+ intptr_t offset;
+ intptr_t buflen;
+ struct percpu_memcpy_buffer_node *array;
+} __attribute__((aligned(128)));
+
+struct percpu_memcpy_buffer {
+ struct percpu_memcpy_buffer_entry c[CPU_SETSIZE];
+};
+
+/* A simple percpu spinlock. Grabs lock on current cpu. */
+static int rseq_this_cpu_lock(struct percpu_lock *lock)
+{
+ int cpu;
+
+ for (;;) {
+ int ret;
+
+ cpu = rseq_cpu_start();
+ ret = rseq_cmpeqv_storev(&lock->c[cpu].v,
+ 0, 1, cpu);
+ if (rseq_likely(!ret))
+ break;
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ /*
+ * Acquire semantic when taking lock after control dependency.
+ * Matches rseq_smp_store_release().
+ */
+ rseq_smp_acquire__after_ctrl_dep();
+ return cpu;
+}
+
+static void rseq_percpu_unlock(struct percpu_lock *lock, int cpu)
+{
+ assert(lock->c[cpu].v == 1);
+ /*
+ * Release lock, with release semantic. Matches
+ * rseq_smp_acquire__after_ctrl_dep().
+ */
+ rseq_smp_store_release(&lock->c[cpu].v, 0);
+}
+
+void *test_percpu_spinlock_thread(void *arg)
+{
+ struct spinlock_thread_test_data *thread_data = arg;
+ struct spinlock_test_data *data = thread_data->data;
+ long long i, reps;
+
+ if (!opt_disable_rseq && thread_data->reg &&
+ rseq_register_current_thread())
+ abort();
+ reps = thread_data->reps;
+ for (i = 0; i < reps; i++) {
+ int cpu = rseq_cpu_start();
+
+ cpu = rseq_this_cpu_lock(&data->lock);
+ data->c[cpu].count++;
+ rseq_percpu_unlock(&data->lock, cpu);
+#ifndef BENCHMARK
+ if (i != 0 && !(i % (reps / 10)))
+ printf_verbose("tid %d: count %lld\n", (int) gettid(), i);
+#endif
+ }
+ printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
+ (int) gettid(), nr_abort, signals_delivered);
+ if (!opt_disable_rseq && thread_data->reg &&
+ rseq_unregister_current_thread())
+ abort();
+ return NULL;
+}
+
+/*
+ * A simple test which implements a sharded counter using a per-cpu
+ * lock. Obviously real applications might prefer to simply use a
+ * per-cpu increment; however, this is reasonable for a test and the
+ * lock can be extended to synchronize more complicated operations.
+ */
+void test_percpu_spinlock(void)
+{
+ const int num_threads = opt_threads;
+ int i, ret;
+ uint64_t sum;
+ pthread_t test_threads[num_threads];
+ struct spinlock_test_data data;
+ struct spinlock_thread_test_data thread_data[num_threads];
+
+ memset(&data, 0, sizeof(data));
+ for (i = 0; i < num_threads; i++) {
+ thread_data[i].reps = opt_reps;
+ if (opt_disable_mod <= 0 || (i % opt_disable_mod))
+ thread_data[i].reg = 1;
+ else
+ thread_data[i].reg = 0;
+ thread_data[i].data = &data;
+ ret = pthread_create(&test_threads[i], NULL,
+ test_percpu_spinlock_thread,
+ &thread_data[i]);
+ if (ret) {
+ errno = ret;
+ perror("pthread_create");
+ abort();
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_join(test_threads[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("pthread_join");
+ abort();
+ }
+ }
+
+ sum = 0;
+ for (i = 0; i < CPU_SETSIZE; i++)
+ sum += data.c[i].count;
+
+ assert(sum == (uint64_t)opt_reps * num_threads);
+}
+
+void *test_percpu_inc_thread(void *arg)
+{
+ struct inc_thread_test_data *thread_data = arg;
+ struct inc_test_data *data = thread_data->data;
+ long long i, reps;
+
+ if (!opt_disable_rseq && thread_data->reg &&
+ rseq_register_current_thread())
+ abort();
+ reps = thread_data->reps;
+ for (i = 0; i < reps; i++) {
+ int ret;
+
+ do {
+ int cpu;
+
+ cpu = rseq_cpu_start();
+ ret = rseq_addv(&data->c[cpu].count, 1, cpu);
+ } while (rseq_unlikely(ret));
+#ifndef BENCHMARK
+ if (i != 0 && !(i % (reps / 10)))
+ printf_verbose("tid %d: count %lld\n", (int) gettid(), i);
+#endif
+ }
+ printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
+ (int) gettid(), nr_abort, signals_delivered);
+ if (!opt_disable_rseq && thread_data->reg &&
+ rseq_unregister_current_thread())
+ abort();
+ return NULL;
+}
+
+void test_percpu_inc(void)
+{
+ const int num_threads = opt_threads;
+ int i, ret;
+ uint64_t sum;
+ pthread_t test_threads[num_threads];
+ struct inc_test_data data;
+ struct inc_thread_test_data thread_data[num_threads];
+
+ memset(&data, 0, sizeof(data));
+ for (i = 0; i < num_threads; i++) {
+ thread_data[i].reps = opt_reps;
+ if (opt_disable_mod <= 0 || (i % opt_disable_mod))
+ thread_data[i].reg = 1;
+ else
+ thread_data[i].reg = 0;
+ thread_data[i].data = &data;
+ ret = pthread_create(&test_threads[i], NULL,
+ test_percpu_inc_thread,
+ &thread_data[i]);
+ if (ret) {
+ errno = ret;
+ perror("pthread_create");
+ abort();
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_join(test_threads[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("pthread_join");
+ abort();
+ }
+ }
+
+ sum = 0;
+ for (i = 0; i < CPU_SETSIZE; i++)
+ sum += data.c[i].count;
+
+ assert(sum == (uint64_t)opt_reps * num_threads);
+}
+
+void this_cpu_list_push(struct percpu_list *list,
+ struct percpu_list_node *node,
+ int *_cpu)
+{
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr, newval, expect;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ /* Load list->c[cpu].head with single-copy atomicity. */
+ expect = (intptr_t)RSEQ_READ_ONCE(list->c[cpu].head);
+ newval = (intptr_t)node;
+ targetptr = (intptr_t *)&list->c[cpu].head;
+ node->next = (struct percpu_list_node *)expect;
+ ret = rseq_cmpeqv_storev(targetptr, expect, newval, cpu);
+ if (rseq_likely(!ret))
+ break;
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+}
+
+/*
+ * Unlike a traditional lock-less linked list; the availability of a
+ * rseq primitive allows us to implement pop without concerns over
+ * ABA-type races.
+ */
+struct percpu_list_node *this_cpu_list_pop(struct percpu_list *list,
+ int *_cpu)
+{
+ struct percpu_list_node *node = NULL;
+ int cpu;
+
+ for (;;) {
+ struct percpu_list_node *head;
+ intptr_t *targetptr, expectnot, *load;
+ off_t offset;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ targetptr = (intptr_t *)&list->c[cpu].head;
+ expectnot = (intptr_t)NULL;
+ offset = offsetof(struct percpu_list_node, next);
+ load = (intptr_t *)&head;
+ ret = rseq_cmpnev_storeoffp_load(targetptr, expectnot,
+ offset, load, cpu);
+ if (rseq_likely(!ret)) {
+ node = head;
+ break;
+ }
+ if (ret > 0)
+ break;
+ /* Retry if rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+ return node;
+}
+
+/*
+ * __percpu_list_pop is not safe against concurrent accesses. Should
+ * only be used on lists that are not concurrently modified.
+ */
+struct percpu_list_node *__percpu_list_pop(struct percpu_list *list, int cpu)
+{
+ struct percpu_list_node *node;
+
+ node = list->c[cpu].head;
+ if (!node)
+ return NULL;
+ list->c[cpu].head = node->next;
+ return node;
+}
+
+void *test_percpu_list_thread(void *arg)
+{
+ long long i, reps;
+ struct percpu_list *list = (struct percpu_list *)arg;
+
+ if (!opt_disable_rseq && rseq_register_current_thread())
+ abort();
+
+ reps = opt_reps;
+ for (i = 0; i < reps; i++) {
+ struct percpu_list_node *node;
+
+ node = this_cpu_list_pop(list, NULL);
+ if (opt_yield)
+ sched_yield(); /* encourage shuffling */
+ if (node)
+ this_cpu_list_push(list, node, NULL);
+ }
+
+ printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
+ (int) gettid(), nr_abort, signals_delivered);
+ if (!opt_disable_rseq && rseq_unregister_current_thread())
+ abort();
+
+ return NULL;
+}
+
+/* Simultaneous modification to a per-cpu linked list from many threads. */
+void test_percpu_list(void)
+{
+ const int num_threads = opt_threads;
+ int i, j, ret;
+ uint64_t sum = 0, expected_sum = 0;
+ struct percpu_list list;
+ pthread_t test_threads[num_threads];
+ cpu_set_t allowed_cpus;
+
+ memset(&list, 0, sizeof(list));
+
+ /* Generate list entries for every usable cpu. */
+ sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+ for (j = 1; j <= 100; j++) {
+ struct percpu_list_node *node;
+
+ expected_sum += j;
+
+ node = malloc(sizeof(*node));
+ assert(node);
+ node->data = j;
+ node->next = list.c[i].head;
+ list.c[i].head = node;
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_create(&test_threads[i], NULL,
+ test_percpu_list_thread, &list);
+ if (ret) {
+ errno = ret;
+ perror("pthread_create");
+ abort();
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_join(test_threads[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("pthread_join");
+ abort();
+ }
+ }
+
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ struct percpu_list_node *node;
+
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+
+ while ((node = __percpu_list_pop(&list, i))) {
+ sum += node->data;
+ free(node);
+ }
+ }
+
+ /*
+ * All entries should now be accounted for (unless some external
+ * actor is interfering with our allowed affinity while this
+ * test is running).
+ */
+ assert(sum == expected_sum);
+}
+
+bool this_cpu_buffer_push(struct percpu_buffer *buffer,
+ struct percpu_buffer_node *node,
+ int *_cpu)
+{
+ bool result = false;
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr_spec, newval_spec;
+ intptr_t *targetptr_final, newval_final;
+ intptr_t offset;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
+ if (offset == buffer->c[cpu].buflen)
+ break;
+ newval_spec = (intptr_t)node;
+ targetptr_spec = (intptr_t *)&buffer->c[cpu].array[offset];
+ newval_final = offset + 1;
+ targetptr_final = &buffer->c[cpu].offset;
+ if (opt_mb)
+ ret = rseq_cmpeqv_trystorev_storev_release(
+ targetptr_final, offset, targetptr_spec,
+ newval_spec, newval_final, cpu);
+ else
+ ret = rseq_cmpeqv_trystorev_storev(targetptr_final,
+ offset, targetptr_spec, newval_spec,
+ newval_final, cpu);
+ if (rseq_likely(!ret)) {
+ result = true;
+ break;
+ }
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+ return result;
+}
+
+struct percpu_buffer_node *this_cpu_buffer_pop(struct percpu_buffer *buffer,
+ int *_cpu)
+{
+ struct percpu_buffer_node *head;
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr, newval;
+ intptr_t offset;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ /* Load offset with single-copy atomicity. */
+ offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
+ if (offset == 0) {
+ head = NULL;
+ break;
+ }
+ head = RSEQ_READ_ONCE(buffer->c[cpu].array[offset - 1]);
+ newval = offset - 1;
+ targetptr = (intptr_t *)&buffer->c[cpu].offset;
+ ret = rseq_cmpeqv_cmpeqv_storev(targetptr, offset,
+ (intptr_t *)&buffer->c[cpu].array[offset - 1],
+ (intptr_t)head, newval, cpu);
+ if (rseq_likely(!ret))
+ break;
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+ return head;
+}
+
+/*
+ * __percpu_buffer_pop is not safe against concurrent accesses. Should
+ * only be used on buffers that are not concurrently modified.
+ */
+struct percpu_buffer_node *__percpu_buffer_pop(struct percpu_buffer *buffer,
+ int cpu)
+{
+ struct percpu_buffer_node *head;
+ intptr_t offset;
+
+ offset = buffer->c[cpu].offset;
+ if (offset == 0)
+ return NULL;
+ head = buffer->c[cpu].array[offset - 1];
+ buffer->c[cpu].offset = offset - 1;
+ return head;
+}
+
+void *test_percpu_buffer_thread(void *arg)
+{
+ long long i, reps;
+ struct percpu_buffer *buffer = (struct percpu_buffer *)arg;
+
+ if (!opt_disable_rseq && rseq_register_current_thread())
+ abort();
+
+ reps = opt_reps;
+ for (i = 0; i < reps; i++) {
+ struct percpu_buffer_node *node;
+
+ node = this_cpu_buffer_pop(buffer, NULL);
+ if (opt_yield)
+ sched_yield(); /* encourage shuffling */
+ if (node) {
+ if (!this_cpu_buffer_push(buffer, node, NULL)) {
+ /* Should increase buffer size. */
+ abort();
+ }
+ }
+ }
+
+ printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
+ (int) gettid(), nr_abort, signals_delivered);
+ if (!opt_disable_rseq && rseq_unregister_current_thread())
+ abort();
+
+ return NULL;
+}
+
+/* Simultaneous modification to a per-cpu buffer from many threads. */
+void test_percpu_buffer(void)
+{
+ const int num_threads = opt_threads;
+ int i, j, ret;
+ uint64_t sum = 0, expected_sum = 0;
+ struct percpu_buffer buffer;
+ pthread_t test_threads[num_threads];
+ cpu_set_t allowed_cpus;
+
+ memset(&buffer, 0, sizeof(buffer));
+
+ /* Generate list entries for every usable cpu. */
+ sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+ /* Worse-case is every item in same CPU. */
+ buffer.c[i].array =
+ malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
+ BUFFER_ITEM_PER_CPU);
+ assert(buffer.c[i].array);
+ buffer.c[i].buflen = CPU_SETSIZE * BUFFER_ITEM_PER_CPU;
+ for (j = 1; j <= BUFFER_ITEM_PER_CPU; j++) {
+ struct percpu_buffer_node *node;
+
+ expected_sum += j;
+
+ /*
+ * We could theoretically put the word-sized
+ * "data" directly in the buffer. However, we
+ * want to model objects that would not fit
+ * within a single word, so allocate an object
+ * for each node.
+ */
+ node = malloc(sizeof(*node));
+ assert(node);
+ node->data = j;
+ buffer.c[i].array[j - 1] = node;
+ buffer.c[i].offset++;
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_create(&test_threads[i], NULL,
+ test_percpu_buffer_thread, &buffer);
+ if (ret) {
+ errno = ret;
+ perror("pthread_create");
+ abort();
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_join(test_threads[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("pthread_join");
+ abort();
+ }
+ }
+
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ struct percpu_buffer_node *node;
+
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+
+ while ((node = __percpu_buffer_pop(&buffer, i))) {
+ sum += node->data;
+ free(node);
+ }
+ free(buffer.c[i].array);
+ }
+
+ /*
+ * All entries should now be accounted for (unless some external
+ * actor is interfering with our allowed affinity while this
+ * test is running).
+ */
+ assert(sum == expected_sum);
+}
+
+bool this_cpu_memcpy_buffer_push(struct percpu_memcpy_buffer *buffer,
+ struct percpu_memcpy_buffer_node item,
+ int *_cpu)
+{
+ bool result = false;
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr_final, newval_final, offset;
+ char *destptr, *srcptr;
+ size_t copylen;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ /* Load offset with single-copy atomicity. */
+ offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
+ if (offset == buffer->c[cpu].buflen)
+ break;
+ destptr = (char *)&buffer->c[cpu].array[offset];
+ srcptr = (char *)&item;
+ /* copylen must be <= 4kB. */
+ copylen = sizeof(item);
+ newval_final = offset + 1;
+ targetptr_final = &buffer->c[cpu].offset;
+ if (opt_mb)
+ ret = rseq_cmpeqv_trymemcpy_storev_release(
+ targetptr_final, offset,
+ destptr, srcptr, copylen,
+ newval_final, cpu);
+ else
+ ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final,
+ offset, destptr, srcptr, copylen,
+ newval_final, cpu);
+ if (rseq_likely(!ret)) {
+ result = true;
+ break;
+ }
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+ return result;
+}
+
+bool this_cpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
+ struct percpu_memcpy_buffer_node *item,
+ int *_cpu)
+{
+ bool result = false;
+ int cpu;
+
+ for (;;) {
+ intptr_t *targetptr_final, newval_final, offset;
+ char *destptr, *srcptr;
+ size_t copylen;
+ int ret;
+
+ cpu = rseq_cpu_start();
+ /* Load offset with single-copy atomicity. */
+ offset = RSEQ_READ_ONCE(buffer->c[cpu].offset);
+ if (offset == 0)
+ break;
+ destptr = (char *)item;
+ srcptr = (char *)&buffer->c[cpu].array[offset - 1];
+ /* copylen must be <= 4kB. */
+ copylen = sizeof(*item);
+ newval_final = offset - 1;
+ targetptr_final = &buffer->c[cpu].offset;
+ ret = rseq_cmpeqv_trymemcpy_storev(targetptr_final,
+ offset, destptr, srcptr, copylen,
+ newval_final, cpu);
+ if (rseq_likely(!ret)) {
+ result = true;
+ break;
+ }
+ /* Retry if comparison fails or rseq aborts. */
+ }
+ if (_cpu)
+ *_cpu = cpu;
+ return result;
+}
+
+/*
+ * __percpu_memcpy_buffer_pop is not safe against concurrent accesses. Should
+ * only be used on buffers that are not concurrently modified.
+ */
+bool __percpu_memcpy_buffer_pop(struct percpu_memcpy_buffer *buffer,
+ struct percpu_memcpy_buffer_node *item,
+ int cpu)
+{
+ intptr_t offset;
+
+ offset = buffer->c[cpu].offset;
+ if (offset == 0)
+ return false;
+ memcpy(item, &buffer->c[cpu].array[offset - 1], sizeof(*item));
+ buffer->c[cpu].offset = offset - 1;
+ return true;
+}
+
+void *test_percpu_memcpy_buffer_thread(void *arg)
+{
+ long long i, reps;
+ struct percpu_memcpy_buffer *buffer = (struct percpu_memcpy_buffer *)arg;
+
+ if (!opt_disable_rseq && rseq_register_current_thread())
+ abort();
+
+ reps = opt_reps;
+ for (i = 0; i < reps; i++) {
+ struct percpu_memcpy_buffer_node item;
+ bool result;
+
+ result = this_cpu_memcpy_buffer_pop(buffer, &item, NULL);
+ if (opt_yield)
+ sched_yield(); /* encourage shuffling */
+ if (result) {
+ if (!this_cpu_memcpy_buffer_push(buffer, item, NULL)) {
+ /* Should increase buffer size. */
+ abort();
+ }
+ }
+ }
+
+ printf_verbose("tid %d: number of rseq abort: %d, signals delivered: %u\n",
+ (int) gettid(), nr_abort, signals_delivered);
+ if (!opt_disable_rseq && rseq_unregister_current_thread())
+ abort();
+
+ return NULL;
+}
+
+/* Simultaneous modification to a per-cpu buffer from many threads. */
+void test_percpu_memcpy_buffer(void)
+{
+ const int num_threads = opt_threads;
+ int i, j, ret;
+ uint64_t sum = 0, expected_sum = 0;
+ struct percpu_memcpy_buffer buffer;
+ pthread_t test_threads[num_threads];
+ cpu_set_t allowed_cpus;
+
+ memset(&buffer, 0, sizeof(buffer));
+
+ /* Generate list entries for every usable cpu. */
+ sched_getaffinity(0, sizeof(allowed_cpus), &allowed_cpus);
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+ /* Worse-case is every item in same CPU. */
+ buffer.c[i].array =
+ malloc(sizeof(*buffer.c[i].array) * CPU_SETSIZE *
+ MEMCPY_BUFFER_ITEM_PER_CPU);
+ assert(buffer.c[i].array);
+ buffer.c[i].buflen = CPU_SETSIZE * MEMCPY_BUFFER_ITEM_PER_CPU;
+ for (j = 1; j <= MEMCPY_BUFFER_ITEM_PER_CPU; j++) {
+ expected_sum += 2 * j + 1;
+
+ /*
+ * We could theoretically put the word-sized
+ * "data" directly in the buffer. However, we
+ * want to model objects that would not fit
+ * within a single word, so allocate an object
+ * for each node.
+ */
+ buffer.c[i].array[j - 1].data1 = j;
+ buffer.c[i].array[j - 1].data2 = j + 1;
+ buffer.c[i].offset++;
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_create(&test_threads[i], NULL,
+ test_percpu_memcpy_buffer_thread,
+ &buffer);
+ if (ret) {
+ errno = ret;
+ perror("pthread_create");
+ abort();
+ }
+ }
+
+ for (i = 0; i < num_threads; i++) {
+ ret = pthread_join(test_threads[i], NULL);
+ if (ret) {
+ errno = ret;
+ perror("pthread_join");
+ abort();
+ }
+ }
+
+ for (i = 0; i < CPU_SETSIZE; i++) {
+ struct percpu_memcpy_buffer_node item;
+
+ if (!CPU_ISSET(i, &allowed_cpus))
+ continue;
+
+ while (__percpu_memcpy_buffer_pop(&buffer, &item, i)) {
+ sum += item.data1;
+ sum += item.data2;
+ }
+ free(buffer.c[i].array);
+ }
+
+ /*
+ * All entries should now be accounted for (unless some external
+ * actor is interfering with our allowed affinity while this
+ * test is running).
+ */
+ assert(sum == expected_sum);
+}
+
+static void test_signal_interrupt_handler(int signo)
+{
+ signals_delivered++;
+}
+
+static int set_signal_handler(void)
+{
+ int ret = 0;
+ struct sigaction sa;
+ sigset_t sigset;
+
+ ret = sigemptyset(&sigset);
+ if (ret < 0) {
+ perror("sigemptyset");
+ return ret;
+ }
+
+ sa.sa_handler = test_signal_interrupt_handler;
+ sa.sa_mask = sigset;
+ sa.sa_flags = 0;
+ ret = sigaction(SIGUSR1, &sa, NULL);
+ if (ret < 0) {
+ perror("sigaction");
+ return ret;
+ }
+
+ printf_verbose("Signal handler set for SIGUSR1\n");
+
+ return ret;
+}
+
+static void show_usage(int argc, char **argv)
+{
+ printf("Usage : %s <OPTIONS>\n",
+ argv[0]);
+ printf("OPTIONS:\n");
+ printf(" [-1 loops] Number of loops for delay injection 1\n");
+ printf(" [-2 loops] Number of loops for delay injection 2\n");
+ printf(" [-3 loops] Number of loops for delay injection 3\n");
+ printf(" [-4 loops] Number of loops for delay injection 4\n");
+ printf(" [-5 loops] Number of loops for delay injection 5\n");
+ printf(" [-6 loops] Number of loops for delay injection 6\n");
+ printf(" [-7 loops] Number of loops for delay injection 7 (-1 to enable -m)\n");
+ printf(" [-8 loops] Number of loops for delay injection 8 (-1 to enable -m)\n");
+ printf(" [-9 loops] Number of loops for delay injection 9 (-1 to enable -m)\n");
+ printf(" [-m N] Yield/sleep/kill every modulo N (default 0: disabled) (>= 0)\n");
+ printf(" [-y] Yield\n");
+ printf(" [-k] Kill thread with signal\n");
+ printf(" [-s S] S: =0: disabled (default), >0: sleep time (ms)\n");
+ printf(" [-t N] Number of threads (default 200)\n");
+ printf(" [-r N] Number of repetitions per thread (default 5000)\n");
+ printf(" [-d] Disable rseq system call (no initialization)\n");
+ printf(" [-D M] Disable rseq for each M threads\n");
+ printf(" [-T test] Choose test: (s)pinlock, (l)ist, (b)uffer, (m)emcpy, (i)ncrement\n");
+ printf(" [-M] Push into buffer and memcpy buffer with memory barriers.\n");
+ printf(" [-v] Verbose output.\n");
+ printf(" [-h] Show this help.\n");
+ printf("\n");
+}
+
+int main(int argc, char **argv)
+{
+ int i;
+
+ for (i = 1; i < argc; i++) {
+ if (argv[i][0] != '-')
+ continue;
+ switch (argv[i][1]) {
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ loop_cnt[argv[i][1] - '0'] = atol(argv[i + 1]);
+ i++;
+ break;
+ case 'm':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_modulo = atol(argv[i + 1]);
+ if (opt_modulo < 0) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 's':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_sleep = atol(argv[i + 1]);
+ if (opt_sleep < 0) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 'y':
+ opt_yield = 1;
+ break;
+ case 'k':
+ opt_signal = 1;
+ break;
+ case 'd':
+ opt_disable_rseq = 1;
+ break;
+ case 'D':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_disable_mod = atol(argv[i + 1]);
+ if (opt_disable_mod < 0) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 't':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_threads = atol(argv[i + 1]);
+ if (opt_threads < 0) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 'r':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_reps = atoll(argv[i + 1]);
+ if (opt_reps < 0) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 'h':
+ show_usage(argc, argv);
+ goto end;
+ case 'T':
+ if (argc < i + 2) {
+ show_usage(argc, argv);
+ goto error;
+ }
+ opt_test = *argv[i + 1];
+ switch (opt_test) {
+ case 's':
+ case 'l':
+ case 'i':
+ case 'b':
+ case 'm':
+ break;
+ default:
+ show_usage(argc, argv);
+ goto error;
+ }
+ i++;
+ break;
+ case 'v':
+ verbose = 1;
+ break;
+ case 'M':
+ opt_mb = 1;
+ break;
+ default:
+ show_usage(argc, argv);
+ goto error;
+ }
+ }
+
+ loop_cnt_1 = loop_cnt[1];
+ loop_cnt_2 = loop_cnt[2];
+ loop_cnt_3 = loop_cnt[3];
+ loop_cnt_4 = loop_cnt[4];
+ loop_cnt_5 = loop_cnt[5];
+ loop_cnt_6 = loop_cnt[6];
+
+ if (set_signal_handler())
+ goto error;
+
+ if (!opt_disable_rseq && rseq_register_current_thread())
+ goto error;
+ switch (opt_test) {
+ case 's':
+ printf_verbose("spinlock\n");
+ test_percpu_spinlock();
+ break;
+ case 'l':
+ printf_verbose("linked list\n");
+ test_percpu_list();
+ break;
+ case 'b':
+ printf_verbose("buffer\n");
+ test_percpu_buffer();
+ break;
+ case 'm':
+ printf_verbose("memcpy buffer\n");
+ test_percpu_memcpy_buffer();
+ break;
+ case 'i':
+ printf_verbose("counter increment\n");
+ test_percpu_inc();
+ break;
+ }
+ if (!opt_disable_rseq && rseq_unregister_current_thread())
+ abort();
+end:
+ return 0;
+
+error:
+ return -1;
+}
--
2.11.0
^ permalink raw reply related
* [RFC PATCH for 4.18 16/16] rseq: selftests: Provide Makefile, scripts, gitignore (v2)
From: Mathieu Desnoyers @ 2018-06-02 12:44 UTC (permalink / raw)
To: Peter Zijlstra, Paul E . McKenney, Boqun Feng, Andy Lutomirski,
Dave Watson
Cc: linux-kernel, linux-api, Paul Turner, Andrew Morton, Russell King,
Thomas Gleixner, Ingo Molnar, H . Peter Anvin, Andrew Hunter,
Andi Kleen, Chris Lameter, Ben Maurer, Steven Rostedt,
Josh Triplett, Linus Torvalds, Catalin Marinas, Will Deacon,
Michael Kerrisk, Joel Fernandes, Mathieu Desnoyers, Shuah Khan
In-Reply-To: <20180602124408.8430-1-mathieu.desnoyers@efficios.com>
A run_param_test.sh script runs many variants of the parametrizable
tests.
Wire up the rseq Makefile, add directory entry into MAINTAINERS file.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC: Shuah Khan <shuahkh@osg.samsung.com>
CC: Russell King <linux@arm.linux.org.uk>
CC: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul Turner <pjt@google.com>
CC: Andrew Hunter <ahh@google.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Andi Kleen <andi@firstfloor.org>
CC: Dave Watson <davejwatson@fb.com>
CC: Chris Lameter <cl@linux.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ben Maurer <bmaurer@fb.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
CC: Josh Triplett <josh@joshtriplett.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Boqun Feng <boqun.feng@gmail.com>
CC: linux-kselftest@vger.kernel.org
CC: linux-api@vger.kernel.org
---
Changes since v1:
- Use only rseq, remove use of cpu_opv.
---
MAINTAINERS | 1 +
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/rseq/.gitignore | 6 ++
tools/testing/selftests/rseq/Makefile | 30 ++++++
tools/testing/selftests/rseq/run_param_test.sh | 121 +++++++++++++++++++++++++
5 files changed, 159 insertions(+)
create mode 100644 tools/testing/selftests/rseq/.gitignore
create mode 100644 tools/testing/selftests/rseq/Makefile
create mode 100755 tools/testing/selftests/rseq/run_param_test.sh
diff --git a/MAINTAINERS b/MAINTAINERS
index be42f5bfc0c9..720b57fac5db 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11982,6 +11982,7 @@ S: Supported
F: kernel/rseq.c
F: include/uapi/linux/rseq.h
F: include/trace/events/rseq.h
+F: tools/testing/selftests/rseq/
RFKILL
M: Johannes Berg <johannes@sipsolutions.net>
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 32aafa92074c..593fb44c9cd4 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -28,6 +28,7 @@ TARGETS += powerpc
TARGETS += proc
TARGETS += pstore
TARGETS += ptrace
+TARGETS += rseq
TARGETS += seccomp
TARGETS += sigaltstack
TARGETS += size
diff --git a/tools/testing/selftests/rseq/.gitignore b/tools/testing/selftests/rseq/.gitignore
new file mode 100644
index 000000000000..cc610da7e369
--- /dev/null
+++ b/tools/testing/selftests/rseq/.gitignore
@@ -0,0 +1,6 @@
+basic_percpu_ops_test
+basic_test
+basic_rseq_op_test
+param_test
+param_test_benchmark
+param_test_compare_twice
diff --git a/tools/testing/selftests/rseq/Makefile b/tools/testing/selftests/rseq/Makefile
new file mode 100644
index 000000000000..c30c52e1d0d2
--- /dev/null
+++ b/tools/testing/selftests/rseq/Makefile
@@ -0,0 +1,30 @@
+# SPDX-License-Identifier: GPL-2.0+ OR MIT
+CFLAGS += -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./
+LDLIBS += -lpthread
+
+# Own dependencies because we only want to build against 1st prerequisite, but
+# still track changes to header files and depend on shared object.
+OVERRIDE_TARGETS = 1
+
+TEST_GEN_PROGS = basic_test basic_percpu_ops_test param_test \
+ param_test_benchmark param_test_compare_twice
+
+TEST_GEN_PROGS_EXTENDED = librseq.so
+
+TEST_PROGS = run_param_test.sh
+
+include ../lib.mk
+
+$(OUTPUT)/librseq.so: rseq.c rseq.h rseq-*.h
+ $(CC) $(CFLAGS) -shared -fPIC $< $(LDLIBS) -o $@
+
+$(OUTPUT)/%: %.c $(TEST_GEN_PROGS_EXTENDED) rseq.h rseq-*.h
+ $(CC) $(CFLAGS) $< $(LDLIBS) -lrseq -o $@
+
+$(OUTPUT)/param_test_benchmark: param_test.c $(TEST_GEN_PROGS_EXTENDED) \
+ rseq.h rseq-*.h
+ $(CC) $(CFLAGS) -DBENCHMARK $< $(LDLIBS) -lrseq -o $@
+
+$(OUTPUT)/param_test_compare_twice: param_test.c $(TEST_GEN_PROGS_EXTENDED) \
+ rseq.h rseq-*.h
+ $(CC) $(CFLAGS) -DRSEQ_COMPARE_TWICE $< $(LDLIBS) -lrseq -o $@
diff --git a/tools/testing/selftests/rseq/run_param_test.sh b/tools/testing/selftests/rseq/run_param_test.sh
new file mode 100755
index 000000000000..3acd6d75ff9f
--- /dev/null
+++ b/tools/testing/selftests/rseq/run_param_test.sh
@@ -0,0 +1,121 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+ or MIT
+
+EXTRA_ARGS=${@}
+
+OLDIFS="$IFS"
+IFS=$'\n'
+TEST_LIST=(
+ "-T s"
+ "-T l"
+ "-T b"
+ "-T b -M"
+ "-T m"
+ "-T m -M"
+ "-T i"
+)
+
+TEST_NAME=(
+ "spinlock"
+ "list"
+ "buffer"
+ "buffer with barrier"
+ "memcpy"
+ "memcpy with barrier"
+ "increment"
+)
+IFS="$OLDIFS"
+
+REPS=1000
+SLOW_REPS=100
+
+function do_tests()
+{
+ local i=0
+ while [ "$i" -lt "${#TEST_LIST[@]}" ]; do
+ echo "Running test ${TEST_NAME[$i]}"
+ ./param_test ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1
+ echo "Running compare-twice test ${TEST_NAME[$i]}"
+ ./param_test_compare_twice ${TEST_LIST[$i]} -r ${REPS} ${@} ${EXTRA_ARGS} || exit 1
+ let "i++"
+ done
+}
+
+echo "Default parameters"
+do_tests
+
+echo "Loop injection: 10000 loops"
+
+OLDIFS="$IFS"
+IFS=$'\n'
+INJECT_LIST=(
+ "1"
+ "2"
+ "3"
+ "4"
+ "5"
+ "6"
+ "7"
+ "8"
+ "9"
+)
+IFS="$OLDIFS"
+
+NR_LOOPS=10000
+
+i=0
+while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do
+ echo "Injecting at <${INJECT_LIST[$i]}>"
+ do_tests -${INJECT_LIST[i]} ${NR_LOOPS}
+ let "i++"
+done
+NR_LOOPS=
+
+function inject_blocking()
+{
+ OLDIFS="$IFS"
+ IFS=$'\n'
+ INJECT_LIST=(
+ "7"
+ "8"
+ "9"
+ )
+ IFS="$OLDIFS"
+
+ NR_LOOPS=-1
+
+ i=0
+ while [ "$i" -lt "${#INJECT_LIST[@]}" ]; do
+ echo "Injecting at <${INJECT_LIST[$i]}>"
+ do_tests -${INJECT_LIST[i]} -1 ${@}
+ let "i++"
+ done
+ NR_LOOPS=
+}
+
+echo "Yield injection (25%)"
+inject_blocking -m 4 -y
+
+echo "Yield injection (50%)"
+inject_blocking -m 2 -y
+
+echo "Yield injection (100%)"
+inject_blocking -m 1 -y
+
+echo "Kill injection (25%)"
+inject_blocking -m 4 -k
+
+echo "Kill injection (50%)"
+inject_blocking -m 2 -k
+
+echo "Kill injection (100%)"
+inject_blocking -m 1 -k
+
+echo "Sleep injection (1ms, 25%)"
+inject_blocking -m 4 -s 1
+
+echo "Sleep injection (1ms, 50%)"
+inject_blocking -m 2 -s 1
+
+echo "Sleep injection (1ms, 100%)"
+inject_blocking -m 1 -s 1
--
2.11.0
^ permalink raw reply related
* Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8]
From: David Howells @ 2018-06-02 15:45 UTC (permalink / raw)
To: Al Viro
Cc: dhowells, Christoph Hellwig, linux-fsdevel, linux-afs,
linux-kernel, linux-api
In-Reply-To: <20180602040434.GW30522@ZenIV.linux.org.uk>
Al Viro <viro@ZenIV.linux.org.uk> wrote:
> TBH, I would probably prefer separate mount_setattr(2) for that kind
> of work, with something like
> int mount_setattr(int dirfd, const char *path, int flags, int attr)
> *not* opening any files.
> flags:
> AT_EMPTY_PATH, AT_NO_AUTOMOUNT, AT_RECURSIVE
I would call these MOUNT_SETATTR_* rather than AT_*.
> attr:
> MOUNT_SETATTR_DEV (1<<0)
> MOUNT_SETATTR_NODEV (1<<0)|(1<<1)
> MOUNT_SETATTR_EXEC (1<<2)
> MOUNT_SETATTR_NOEXEC (1<<2)|(1<<3)
> MOUNT_SETATTR_SUID (1<<4)
> MOUNT_SETATTR_NOSUID (1<<4)|(1<<5)
> MOUNT_SETATTR_RW (1<<6)
> MOUNT_SETATTR_RO (1<<6)|(1<<7)
> MOUNT_SETATTR_RELATIME (1<<8)
> MOUNT_SETATTR_NOATIME (1<<8)|(1<<9)
> MOUNT_SETATTR_NODIRATIME (1<<8)|(2<<9)
> MOUNT_SETATTR_STRICTATIME (1<<8)|(3<<9)
> MOUNT_SETATTR_PRIVATE (1<<11)
> MOUNT_SETATTR_SHARED (1<<11)|(1<<12)
> MOUNT_SETATTR_SLAVE (1<<11)|(2<<12)
> MOUNT_SETATTR_UNBINDABLE (1<<11)|(3<<12)
So, I like this generally, some notes though:
I wonder if this should be two separate parameters, a mask and the settings?
I'm not sure that's worth it since some of the mask bits would cover multiple
settings.
Also, should NODIRATIME be separate from the other *ATIME flags? I do also
like treating some of these settings as enumerations rather than a set of
bits.
I would make the prototype:
int mount_setattr(int dirfd, const char *path,
unsigned int flags, unsigned int attr,
void *reserved5);
Further, do we want to say you can either change the propagation type *or*
reconfigure the mountpoint restrictions, but not both at the same time?
> With either openat() used as in this series, or explicit
> int open_tree(int dirfd, const char *path, int flags)
Maybe open_mount(), grab_mount() or pick_mount()?
I wonder if fsopen()/fspick() should be create_fs()/open_fs()...
> returning a descriptor, with flags being
> AT_EMPTY_PATH, AT_NO_AUTOMOUNT, AT_RECURSIVE, AT_CLONE
> with AT_RECURSIVE without AT_CLONE being an error.
You also need an O_CLOEXEC equivalent.
I would make it:
OPEN_TREE_CLOEXEC 0x00000001
OPEN_TREE_EMPTY_PATH 0x00000002
OPEN_TREE_FOLLOW_SYMLINK 0x00000004
OPEN_TREE_NO_AUTOMOUNT 0x00000008
OPEN_TREE_CLONE 0x00000010
OPEN_TREE_RECURSIVE 0x00000020
adding the follow-symlinks so that you don't grab a symlink target by
accident. (Can you actually mount on top of a symlink?)
> Hell, might even add AT_UMOUNT for "open root and detach, to be dissolved on
> close", incompatible with AT_CLONE.
Cute. Guess you could do:
fd = open_mount(..., OPEN_TREE_DETACH);
mount_setattr(fd, "",
MOUNT_SETATTR_EMPTY_PATH,
MOUNT_SETATTR_NOSUID, NULL);
move_mount(fd, "", ...);
David
^ permalink raw reply
* Re: [PATCH 2/5] lib/rhashtable: guarantee initial hashtable allocation
From: Herbert Xu @ 2018-06-02 15:53 UTC (permalink / raw)
To: Davidlohr Bueso
Cc: akpm, torvalds, tgraf, manfred, mhocko, guillaume.knispel,
linux-api, linux-kernel, Davidlohr Bueso
In-Reply-To: <20180602054131.ta7ligrfwbgvemfv@linux-r8p5>
On Fri, Jun 01, 2018 at 10:41:31PM -0700, Davidlohr Bueso wrote:
> On Sat, 02 Jun 2018, Herbert Xu wrote:
> > > tbl = bucket_table_alloc(ht, size, GFP_KERNEL);
> > > - if (tbl == NULL)
> > > - return -ENOMEM;
> > > + if (unlikely(tbl == NULL)) {
> > > + size = min_t(u16, ht->p.min_size, HASH_MIN_SIZE);
> >
> > You mean max_t?
>
> Not really. I considered some of the users to set quite a large min_size
> (such as 1024 buckets). The min() makes sense to me in that it's the smallest
> possible value. If memory later becomes available and the hashtable is resized
> to a more appropriate value, couldn't any issues regarding collisions not be dealt
> with organically? And we've agreed that allocating a tiny table is the
> least of our problems.
Huh? The min_size is a floor for the hash table size. Some users
may need it because they cannot tolerate the insert-time allocation
or failure.
Your use of min_t against min_size makes absolutely no sense.
Cheers,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
^ permalink raw reply
* Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8]
From: Al Viro @ 2018-06-02 17:49 UTC (permalink / raw)
To: David Howells
Cc: Christoph Hellwig, linux-fsdevel, linux-afs, linux-kernel,
linux-api
In-Reply-To: <21804.1527954321@warthog.procyon.org.uk>
On Sat, Jun 02, 2018 at 04:45:21PM +0100, David Howells wrote:
> Al Viro <viro@ZenIV.linux.org.uk> wrote:
>
> > TBH, I would probably prefer separate mount_setattr(2) for that kind
> > of work, with something like
> > int mount_setattr(int dirfd, const char *path, int flags, int attr)
> > *not* opening any files.
> > flags:
> > AT_EMPTY_PATH, AT_NO_AUTOMOUNT, AT_RECURSIVE
>
> I would call these MOUNT_SETATTR_* rather than AT_*.
Why? AT_EMPTY_PATH/AT_NO_AUTOMOUNT are common with other ...at()
syscalls; AT_RECURSIVE - maybe, but it's still more like AT_...
namespace fodder, IMO.
> > attr:
> > MOUNT_SETATTR_DEV (1<<0)
> > MOUNT_SETATTR_NODEV (1<<0)|(1<<1)
> > MOUNT_SETATTR_EXEC (1<<2)
> > MOUNT_SETATTR_NOEXEC (1<<2)|(1<<3)
> > MOUNT_SETATTR_SUID (1<<4)
> > MOUNT_SETATTR_NOSUID (1<<4)|(1<<5)
> > MOUNT_SETATTR_RW (1<<6)
> > MOUNT_SETATTR_RO (1<<6)|(1<<7)
> > MOUNT_SETATTR_RELATIME (1<<8)
> > MOUNT_SETATTR_NOATIME (1<<8)|(1<<9)
> > MOUNT_SETATTR_NODIRATIME (1<<8)|(2<<9)
> > MOUNT_SETATTR_STRICTATIME (1<<8)|(3<<9)
> > MOUNT_SETATTR_PRIVATE (1<<11)
> > MOUNT_SETATTR_SHARED (1<<11)|(1<<12)
> > MOUNT_SETATTR_SLAVE (1<<11)|(2<<12)
> > MOUNT_SETATTR_UNBINDABLE (1<<11)|(3<<12)
>
> So, I like this generally, some notes though:
>
> I wonder if this should be two separate parameters, a mask and the settings?
> I'm not sure that's worth it since some of the mask bits would cover multiple
> settings.
Nah, better put those bits in the same word, as in above. Here bits 0, 2, 4, 6,
8 and 11 tell which attributes are to be modified, with values to set living
in bits 1, 3, 5, 7, 9--10 and 12--13. Look at the constants above..
> Also, should NODIRATIME be separate from the other *ATIME flags? I do also
> like treating some of these settings as enumerations rather than a set of
> bits.
Huh? That's precisely what I'm doing there: bit 8 is "want to change atime
settings", bits 9 and 10 hold a 4-element enumeration (rel/no/nodir/strict).
Similar for propagation settings (bit 11 indicates that we want to set those,
bits 12 and 13 - 4-element enum)...
> I would make the prototype:
>
> int mount_setattr(int dirfd, const char *path,
> unsigned int flags, unsigned int attr,
> void *reserved5);
>
> Further, do we want to say you can either change the propagation type *or*
> reconfigure the mountpoint restrictions, but not both at the same time?
Why? MOUNT_SETATTR_PRIVATE | MOUNT_NOATIME | MOUNT_SUID, i.e. 00101100010000,
i.e. 0xb10 for "turn nosuid off, switch atime polcy to noatime, change propagation
to private, leave everything else as-is"...
And for fsck sake, what's that "void *reserved5" for?
> > With either openat() used as in this series, or explicit
> > int open_tree(int dirfd, const char *path, int flags)
>
> Maybe open_mount(), grab_mount() or pick_mount()?
>
> I wonder if fsopen()/fspick() should be create_fs()/open_fs()...
>
> > returning a descriptor, with flags being
> > AT_EMPTY_PATH, AT_NO_AUTOMOUNT, AT_RECURSIVE, AT_CLONE
> > with AT_RECURSIVE without AT_CLONE being an error.
>
> You also need an O_CLOEXEC equivalent.
Point.
> I would make it:
>
> OPEN_TREE_CLOEXEC 0x00000001
Why not O_CLOEXEC, as with epoll_create()/timerfd_create()/etc.?
> OPEN_TREE_EMPTY_PATH 0x00000002
> OPEN_TREE_FOLLOW_SYMLINK 0x00000004
> OPEN_TREE_NO_AUTOMOUNT 0x00000008
Why? How are those different from normal AT_EMPTY_PATH/AT_NO_AUTOMOUNT?
> OPEN_TREE_CLONE 0x00000010
> OPEN_TREE_RECURSIVE 0x00000020
>
> adding the follow-symlinks so that you don't grab a symlink target by
> accident. (Can you actually mount on top of a symlink?)
You can't - mount(2) uses LOOKUP_FOLLOW for mountpoint (well, user_path(),
actually).
> > Hell, might even add AT_UMOUNT for "open root and detach, to be dissolved on
> > close", incompatible with AT_CLONE.
>
> Cute. Guess you could do:
>
> fd = open_mount(..., OPEN_TREE_DETACH);
> mount_setattr(fd, "",
> MOUNT_SETATTR_EMPTY_PATH,
> MOUNT_SETATTR_NOSUID, NULL);
> move_mount(fd, "", ...);
^ permalink raw reply
* [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Al Viro @ 2018-06-03 0:55 UTC (permalink / raw)
To: David Howells
Cc: Christoph Hellwig, linux-fsdevel, linux-afs, linux-kernel,
linux-api
In-Reply-To: <20180602174957.GX30522@ZenIV.linux.org.uk>
On Sat, Jun 02, 2018 at 06:49:58PM +0100, Al Viro wrote:
> > > Hell, might even add AT_UMOUNT for "open root and detach, to be dissolved on
> > > close", incompatible with AT_CLONE.
> >
> > Cute. Guess you could do:
> >
> > fd = open_mount(..., OPEN_TREE_DETACH);
> > mount_setattr(fd, "",
> > MOUNT_SETATTR_EMPTY_PATH,
> > MOUNT_SETATTR_NOSUID, NULL);
> > move_mount(fd, "", ...);
Hadn't added that yet, but as for the rest of open_tree() - see
vfs.git#mount-open_tree. open() and its flags are not touched at all.
Other changes compared to the previous:
* may_mount() is required for OPEN_TREE_CLONE
* sys_ni.c cruft is dropped - those make no sense until and unless
those syscalls become conditional.
Appears to work, combined with move_mount() it yields eqiuvalents of
mount --{move,bind,rbind}. Combined with mount_setattr(2) (when that
gets added) we'll get mount -o remount,bind,nodev et.al.
(including the currently absent whole-subtree versions) and
mount --make-{r,}{shared,slave,private,unbindable}
It also can be used to get an isolated subtree usable for ....at()
stuff.
The addition of syscall itself is done by the following and I'd really
like linux-abi folks to comment on that puppy
commit 6cfba4dd99b10278c2156c8d4fced2eddedf167f
Author: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat Jun 2 19:42:22 2018 -0400
new syscall: open_tree(2)
open_tree(dfd, pathname, flags)
Returns an O_PATH-opened file descriptor or an error.
dfd and pathname specify the location to open, in usual
fashion (see e.g. fstatat(2)). flags should be an OR of
some of the following:
* AT_PATH_EMPTY, AT_NO_AUTOMOUNT, AT_SYMLINK_NOFOLLOW -
same meanings as usual
* OPEN_TREE_CLOEXEC - make the resulting descriptor
close-on-exec
* OPEN_TREE_CLONE or OPEN_TREE_CLONE | AT_RECURSIVE -
instead of opening the location in question, create a detached
mount tree matching the subtree rooted at location specified by
dfd/pathname. With AT_RECURSIVE the entire subtree is cloned,
without it - only the part within in the mount containing the
location in question. In other words, the same as mount --rbind
or mount --bind would've taken. The detached tree will be
dissolved on the final close of obtained file. Creation of such
detached trees requires the same capabilities as doing mount --bind.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 14a2f996e543..b2b44ecd2b17 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -397,3 +397,4 @@
383 i386 statx sys_statx __ia32_sys_statx
384 i386 arch_prctl sys_arch_prctl __ia32_compat_sys_arch_prctl
385 i386 io_pgetevents sys_io_pgetevents __ia32_compat_sys_io_pgetevents
+391 i386 open_tree sys_open_tree __ia32_sys_open_tree
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index cd36232ab62f..d6f4949378e7 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -342,6 +342,7 @@
331 common pkey_free __x64_sys_pkey_free
332 common statx __x64_sys_statx
333 common io_pgetevents __x64_sys_io_pgetevents
+339 common open_tree __x64_sys_open_tree
#
# x32-specific system call numbers start at 512 to avoid cache impact
diff --git a/fs/file_table.c b/fs/file_table.c
index 7ec0b3e5f05d..7480271a0d21 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -189,6 +189,7 @@ static void __fput(struct file *file)
struct dentry *dentry = file->f_path.dentry;
struct vfsmount *mnt = file->f_path.mnt;
struct inode *inode = file->f_inode;
+ fmode_t mode = file->f_mode;
might_sleep();
@@ -209,14 +210,14 @@ static void __fput(struct file *file)
file->f_op->release(inode, file);
security_file_free(file);
if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
- !(file->f_mode & FMODE_PATH))) {
+ !(mode & FMODE_PATH))) {
cdev_put(inode->i_cdev);
}
fops_put(file->f_op);
put_pid(file->f_owner.pid);
- if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
+ if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
i_readcount_dec(inode);
- if (file->f_mode & FMODE_WRITER) {
+ if (mode & FMODE_WRITER) {
put_write_access(inode);
__mnt_drop_write(mnt);
}
@@ -224,6 +225,8 @@ static void __fput(struct file *file)
file->f_path.mnt = NULL;
file->f_inode = NULL;
file_free(file);
+ if (unlikely(mode & FMODE_NEED_UNMOUNT))
+ dissolve_on_fput(mnt);
dput(dentry);
mntput(mnt);
}
diff --git a/fs/internal.h b/fs/internal.h
index 980d005b21b4..b55575b9b55c 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -85,6 +85,7 @@ extern void __mnt_drop_write(struct vfsmount *);
extern void __mnt_drop_write_file(struct file *);
extern void mnt_drop_write_file_path(struct file *);
+extern void dissolve_on_fput(struct vfsmount *);
/*
* fs_struct.c
*/
diff --git a/fs/namespace.c b/fs/namespace.c
index 5f75969adff1..3281fea98cf0 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -20,12 +20,14 @@
#include <linux/init.h> /* init_rootfs */
#include <linux/fs_struct.h> /* get_fs_root et.al. */
#include <linux/fsnotify.h> /* fsnotify_vfsmount_delete */
+#include <linux/file.h>
#include <linux/uaccess.h>
#include <linux/proc_ns.h>
#include <linux/magic.h>
#include <linux/bootmem.h>
#include <linux/task_work.h>
#include <linux/sched/task.h>
+#include <uapi/linux/mount.h>
#include "pnode.h"
#include "internal.h"
@@ -1839,6 +1841,16 @@ struct vfsmount *collect_mounts(const struct path *path)
return &tree->mnt;
}
+void dissolve_on_fput(struct vfsmount *mnt)
+{
+ namespace_lock();
+ lock_mount_hash();
+ mntget(mnt);
+ umount_tree(real_mount(mnt), UMOUNT_SYNC);
+ unlock_mount_hash();
+ namespace_unlock();
+}
+
void drop_collected_mounts(struct vfsmount *mnt)
{
namespace_lock();
@@ -2198,6 +2210,30 @@ static bool has_locked_children(struct mount *mnt, struct dentry *dentry)
return false;
}
+static struct mount *__do_loopback(struct path *old_path, int recurse)
+{
+ struct mount *mnt = ERR_PTR(-EINVAL), *old = real_mount(old_path->mnt);
+
+ if (IS_MNT_UNBINDABLE(old))
+ return mnt;
+
+ if (!check_mnt(old) && old_path->dentry->d_op != &ns_dentry_operations)
+ return mnt;
+
+ if (!recurse && has_locked_children(old, old_path->dentry))
+ return mnt;
+
+ if (recurse)
+ mnt = copy_tree(old, old_path->dentry, CL_COPY_MNT_NS_FILE);
+ else
+ mnt = clone_mnt(old, old_path->dentry, 0);
+
+ if (!IS_ERR(mnt))
+ mnt->mnt.mnt_flags &= ~MNT_LOCKED;
+
+ return mnt;
+}
+
/*
* do loopback mount.
*/
@@ -2205,7 +2241,7 @@ static int do_loopback(struct path *path, const char *old_name,
int recurse)
{
struct path old_path;
- struct mount *mnt = NULL, *old, *parent;
+ struct mount *mnt = NULL, *parent;
struct mountpoint *mp;
int err;
if (!old_name || !*old_name)
@@ -2219,38 +2255,21 @@ static int do_loopback(struct path *path, const char *old_name,
goto out;
mp = lock_mount(path);
- err = PTR_ERR(mp);
- if (IS_ERR(mp))
+ if (IS_ERR(mp)) {
+ err = PTR_ERR(mp);
goto out;
+ }
- old = real_mount(old_path.mnt);
parent = real_mount(path->mnt);
-
- err = -EINVAL;
- if (IS_MNT_UNBINDABLE(old))
- goto out2;
-
if (!check_mnt(parent))
goto out2;
- if (!check_mnt(old) && old_path.dentry->d_op != &ns_dentry_operations)
- goto out2;
-
- if (!recurse && has_locked_children(old, old_path.dentry))
- goto out2;
-
- if (recurse)
- mnt = copy_tree(old, old_path.dentry, CL_COPY_MNT_NS_FILE);
- else
- mnt = clone_mnt(old, old_path.dentry, 0);
-
+ mnt = __do_loopback(&old_path, recurse);
if (IS_ERR(mnt)) {
err = PTR_ERR(mnt);
goto out2;
}
- mnt->mnt.mnt_flags &= ~MNT_LOCKED;
-
err = graft_tree(mnt, parent, mp);
if (err) {
lock_mount_hash();
@@ -2264,6 +2283,75 @@ static int do_loopback(struct path *path, const char *old_name,
return err;
}
+SYSCALL_DEFINE3(open_tree, int, dfd, const char *, filename, unsigned, flags)
+{
+ struct file *file;
+ struct path path;
+ int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
+ bool detached = flags & OPEN_TREE_CLONE;
+ int error;
+ int fd;
+
+ BUILD_BUG_ON(OPEN_TREE_CLOEXEC != O_CLOEXEC);
+
+ if (flags & ~(AT_EMPTY_PATH | AT_NO_AUTOMOUNT | AT_RECURSIVE |
+ AT_SYMLINK_NOFOLLOW | OPEN_TREE_CLONE |
+ OPEN_TREE_CLOEXEC))
+ return -EINVAL;
+
+ if ((flags & (AT_RECURSIVE | OPEN_TREE_CLONE)) == AT_RECURSIVE)
+ return -EINVAL;
+
+ if (flags & AT_NO_AUTOMOUNT)
+ lookup_flags &= ~LOOKUP_AUTOMOUNT;
+ if (flags & AT_SYMLINK_NOFOLLOW)
+ lookup_flags &= ~LOOKUP_FOLLOW;
+ if (flags & AT_EMPTY_PATH)
+ lookup_flags |= LOOKUP_EMPTY;
+
+ if (detached && !may_mount())
+ return -EPERM;
+
+ fd = get_unused_fd_flags(flags & O_CLOEXEC);
+ if (fd < 0)
+ return fd;
+
+ error = user_path_at(dfd, filename, lookup_flags, &path);
+ if (error)
+ goto out;
+
+ if (detached) {
+ struct mount *mnt = __do_loopback(&path, flags & AT_RECURSIVE);
+ if (IS_ERR(mnt)) {
+ error = PTR_ERR(mnt);
+ goto out2;
+ }
+ mntput(path.mnt);
+ path.mnt = &mnt->mnt;
+ }
+
+ file = dentry_open(&path, O_PATH, current_cred());
+ if (IS_ERR(file)) {
+ error = PTR_ERR(file);
+ goto out3;
+ }
+
+ if (detached)
+ file->f_mode |= FMODE_NEED_UNMOUNT;
+ path_put(&path);
+ fd_install(fd, file);
+ return fd;
+
+out3:
+ if (detached)
+ dissolve_on_fput(path.mnt);
+out2:
+ path_put(&path);
+out:
+ put_unused_fd(fd);
+ return error;
+}
+
static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
{
int error = 0;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 482563fe549c..706b4605bc26 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -154,6 +154,9 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
/* File is capable of returning -EAGAIN if I/O will block */
#define FMODE_NOWAIT ((__force fmode_t)0x8000000)
+/* File represents mount that needs unmounting */
+#define FMODE_NEED_UNMOUNT ((__force fmode_t)0x10000000)
+
/*
* Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector
* that indicates that they should check the contents of the iovec are
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 811172fcb916..925483aba03a 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -896,7 +896,7 @@ asmlinkage long sys_pkey_alloc(unsigned long flags, unsigned long init_val);
asmlinkage long sys_pkey_free(int pkey);
asmlinkage long sys_statx(int dfd, const char __user *path, unsigned flags,
unsigned mask, struct statx __user *buffer);
-
+asmlinkage long sys_open_tree(int dfd, const char __user *path, unsigned flags);
/*
* Architecture-specific system calls
diff --git a/include/uapi/linux/fcntl.h b/include/uapi/linux/fcntl.h
index 6448cdd9a350..594b85f7cb86 100644
--- a/include/uapi/linux/fcntl.h
+++ b/include/uapi/linux/fcntl.h
@@ -90,5 +90,7 @@
#define AT_STATX_FORCE_SYNC 0x2000 /* - Force the attributes to be sync'd with the server */
#define AT_STATX_DONT_SYNC 0x4000 /* - Don't sync attributes with the server */
+#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */
+
#endif /* _UAPI_LINUX_FCNTL_H */
diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h
new file mode 100644
index 000000000000..b9c3b46210db
--- /dev/null
+++ b/include/uapi/linux/mount.h
@@ -0,0 +1,7 @@
+#ifndef _UAPI_LINUX_MOUNT_H
+#define _UAPI_LINUX_MOUNT_H
+
+#define OPEN_TREE_CLONE 1
+#define OPEN_TREE_CLOEXEC O_CLOEXEC
+
+#endif /* _UAPI_LINUX_MOUNT_H */
^ permalink raw reply related
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Miklos Szeredi @ 2018-06-04 10:34 UTC (permalink / raw)
To: Al Viro
Cc: David Howells, Christoph Hellwig, linux-fsdevel, linux-afs, LKML,
Linux API
In-Reply-To: <20180603005532.GZ30522@ZenIV.linux.org.uk>
On Sun, Jun 3, 2018 at 2:55 AM, Al Viro <viro@zeniv.linux.org.uk> wrote:
> On Sat, Jun 02, 2018 at 06:49:58PM +0100, Al Viro wrote:
>
>> > > Hell, might even add AT_UMOUNT for "open root and detach, to be dissolved on
>> > > close", incompatible with AT_CLONE.
>> >
>> > Cute. Guess you could do:
>> >
>> > fd = open_mount(..., OPEN_TREE_DETACH);
>> > mount_setattr(fd, "",
>> > MOUNT_SETATTR_EMPTY_PATH,
>> > MOUNT_SETATTR_NOSUID, NULL);
>> > move_mount(fd, "", ...);
>
> Hadn't added that yet, but as for the rest of open_tree() - see
> vfs.git#mount-open_tree. open() and its flags are not touched at all.
> Other changes compared to the previous:
> * may_mount() is required for OPEN_TREE_CLONE
> * sys_ni.c cruft is dropped - those make no sense until and unless
> those syscalls become conditional.
>
> Appears to work, combined with move_mount() it yields eqiuvalents of
> mount --{move,bind,rbind}. Combined with mount_setattr(2) (when that
> gets added) we'll get mount -o remount,bind,nodev et.al.
fsopen = create fsfd
fsmount = fsfd -> mountfd & set attr on mountfd & attach mountfd
fspick = path -> fsfd
move_mount = attach mountfd or move existing
fsinfo = info from path
open_tree = new mountfd from path or clone
mount_setattr = set attr on mountfd
Notice that fsmount() encompasses mount_setattr() + move_mount()
functionality. Split those out and leave fsmount() to actually do
the "fsfd ->mountfd" translation?
fsinfo() name suggests it's in the same class as
fsopen/fsmount/fspick, operating on fsfd object, but's it's not and I
think that's slightly confusing.
Rename move_mount() -> mount_move()?
Also does it make sense to make the cloning behavior of open_tree()
optional? Without cloning it's just a plain open(O_PATH). That way
it could be renamed mount_clone().
Thanks,
Miklos
^ permalink raw reply
* Re: [PATCH 2/5] lib/rhashtable: guarantee initial hashtable allocation
From: Michal Hocko @ 2018-06-04 11:46 UTC (permalink / raw)
To: Davidlohr Bueso
Cc: akpm, torvalds, tgraf, herbert, manfred, guillaume.knispel,
linux-api, linux-kernel, Davidlohr Bueso
In-Reply-To: <20180601160125.30031-3-dave@stgolabs.net>
On Fri 01-06-18 09:01:22, Davidlohr Bueso wrote:
[...]
> diff --git a/lib/rhashtable.c b/lib/rhashtable.c
> index 05a4b1b8b8ce..ae17da6f0c75 100644
> --- a/lib/rhashtable.c
> +++ b/lib/rhashtable.c
> @@ -175,7 +175,7 @@ static struct bucket_table *bucket_table_alloc(struct rhashtable *ht,
> int i;
>
> size = sizeof(*tbl) + nbuckets * sizeof(tbl->buckets[0]);
> - if (gfp != GFP_KERNEL)
> + if ((gfp & ~__GFP_NOFAIL) != GFP_KERNEL)
> tbl = kzalloc(size, gfp | __GFP_NOWARN | __GFP_NORETRY);
> else
> tbl = kvzalloc(size, gfp);
Just a heads up. This is not longer needed after
http://lkml.kernel.org/r/20180601115329.27807-1-mhocko@kernel.org
is applied. Moreover it will conflict at that spot.
--
Michal Hocko
SUSE Labs
^ permalink raw reply
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: David Howells @ 2018-06-04 15:27 UTC (permalink / raw)
To: Miklos Szeredi
Cc: dhowells, Al Viro, Christoph Hellwig, linux-fsdevel, linux-afs,
LKML, Linux API
In-Reply-To: <CAELBmZCXMkCY+Lkz2xmhUiK_5oDctZzozHP-cXv9vp7qWsOtVQ@mail.gmail.com>
Miklos Szeredi <miklos@szeredi.hu> wrote:
> fsinfo = info from path
Actually, I was thinking of making fsinfo() detect if it's been given an fsfd
and go through an fs_context operation instead in that case.
David
^ permalink raw reply
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Al Viro @ 2018-06-04 15:52 UTC (permalink / raw)
To: Miklos Szeredi
Cc: David Howells, Christoph Hellwig, linux-fsdevel, linux-afs, LKML,
Linux API
In-Reply-To: <CAELBmZCXMkCY+Lkz2xmhUiK_5oDctZzozHP-cXv9vp7qWsOtVQ@mail.gmail.com>
On Mon, Jun 04, 2018 at 12:34:44PM +0200, Miklos Szeredi wrote:
> fsopen = create fsfd
> fsmount = fsfd -> mountfd & set attr on mountfd & attach mountfd
> fspick = path -> fsfd
> move_mount = attach mountfd or move existing
> fsinfo = info from path
> open_tree = new mountfd from path or clone
> mount_setattr = set attr on mountfd
>
> Notice that fsmount() encompasses mount_setattr() + move_mount()
> functionality. Split those out and leave fsmount() to actually do
> the "fsfd ->mountfd" translation?
Might make sense.
> fsinfo() name suggests it's in the same class as
> fsopen/fsmount/fspick, operating on fsfd object, but's it's not and I
> think that's slightly confusing.
>
> Rename move_mount() -> mount_move()?
mount_move_bikeshed_bikeshed_bikeshed(), surely?
> Also does it make sense to make the cloning behavior of open_tree()
> optional? Without cloning it's just a plain open(O_PATH). That way
> it could be renamed mount_clone().
Umm... I'm not sure about that one. If nothing else, OPEN_TREE_DETACH
might be a good idea, in which case cloning is not the primary effect;
hell knows.
^ permalink raw reply
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Al Viro @ 2018-06-04 15:59 UTC (permalink / raw)
To: Miklos Szeredi
Cc: David Howells, Christoph Hellwig, linux-fsdevel, linux-afs, LKML,
Linux API
In-Reply-To: <20180604155205.GH30522@ZenIV.linux.org.uk>
On Mon, Jun 04, 2018 at 04:52:05PM +0100, Al Viro wrote:
> On Mon, Jun 04, 2018 at 12:34:44PM +0200, Miklos Szeredi wrote:
>
> > fsopen = create fsfd
> > fsmount = fsfd -> mountfd & set attr on mountfd & attach mountfd
> > fspick = path -> fsfd
> > move_mount = attach mountfd or move existing
> > fsinfo = info from path
> > open_tree = new mountfd from path or clone
> > mount_setattr = set attr on mountfd
> >
> > Notice that fsmount() encompasses mount_setattr() + move_mount()
> > functionality. Split those out and leave fsmount() to actually do
> > the "fsfd ->mountfd" translation?
>
> Might make sense.
FWIW, to make it clear: fsmount(2) in this series actually does *NOT*
attach it to the tree. Commit message definitely needs updating - as it
is, it's
+SYSCALL_DEFINE5(fsmount, int, fs_fd, unsigned int, flags, unsigned int, ms_flags,
+ void *, reserved4, void *, reserved5)
PS: IMO these reserved... arguments are in bad taste; if anyone has good reasons
for that practice in ABI design, I'd like to hear those.
^ permalink raw reply
* Re: [RFC PATCH ghak32 V2 01/13] audit: add container id
From: Steve Grubb @ 2018-06-04 16:09 UTC (permalink / raw)
To: Richard Guy Briggs
Cc: linux-api, containers, LKML, eparis, Linux-Audit Mailing List,
linux-fsdevel, viro
In-Reply-To: <20180601210455.boz3tjqeqcx3kucg@madcap2.tricolour.ca>
On Friday, June 1, 2018 5:04:55 PM EDT Richard Guy Briggs wrote:
> Re: [RFC PATCH ghak32 V2 01/13] audit: add container id
>
> From: Richard Guy Briggs <rgb@redhat.com>
> To: Me
> CC: linux-api@vger.kernel.org, containers@lists.linux-foundation.org, LKML
> <linux-kernel@vger.kernel.org>, eparis@parisplace.org, ... Date: 6/1/18
> 5:04 PM
>
> On 2018-05-17 17:00, Steve Grubb wrote:
> > On Fri, 16 Mar 2018 05:00:28 -0400
> >
> > Richard Guy Briggs <rgb@redhat.com> wrote:
> > > Implement the proc fs write to set the audit container ID of a
> > > process, emitting an AUDIT_CONTAINER record to document the event.
> > >
> > > This is a write from the container orchestrator task to a proc entry
> > > of the form /proc/PID/containerid where PID is the process ID of the
> > > newly created task that is to become the first task in a container,
> > > or an additional task added to a container.
> > >
> > > The write expects up to a u64 value (unset: 18446744073709551615).
> > >
> > > This will produce a record such as this:
> > > type=CONTAINER msg=audit(1519903238.968:261): op=set pid=596 uid=0
> > > subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 auid=0
> > > tty=pts0 ses=1 opid=596 old-contid=18446744073709551615 contid=123455
> > > res=0
> >
> > The was one thing I was wondering about. Currently when we set the
> > loginuid, the record is AUDIT_LOGINUID. The corollary is that when we
> > set the container id, the event should be AUDIT_CONTAINERID or
> > AUDIT_CONTAINER_ID.
> >
> > During syscall events, the path info is returned in a a record simply
> > called AUDIT_PATH, cwd info is returned in AUDIT_CWD. So, rather than
> > calling the record that gets attached to everything
> > AUDIT_CONTAINER_INFO, how about simply AUDIT_CONTAINER.
> >
> > > The "op" field indicates an initial set. The "pid" to "ses" fields
> > > are the orchestrator while the "opid" field is the object's PID, the
> > > process being "contained". Old and new container ID values are given
> > > in the "contid" fields, while res indicates its success.
> > >
> > > It is not permitted to self-set, unset or re-set the container ID. A
> > > child inherits its parent's container ID, but then can be set only
> > > once after.
> > >
> > > See: https://github.com/linux-audit/audit-kernel/issues/32
> > >
> > > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> > > ---
> > > fs/proc/base.c | 37 ++++++++++++++++++++
> > > include/linux/audit.h | 16 +++++++++
> > > include/linux/init_task.h | 4 ++-
> > > include/linux/sched.h | 1 +
> > > include/uapi/linux/audit.h | 2 ++
> > > kernel/auditsc.c | 84
> > > ++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 143
> > > insertions(+), 1 deletion(-)
> > >
> > > diff --git a/fs/proc/base.c b/fs/proc/base.c
> > > index 60316b5..6ce4fbe 100644
> > > --- a/fs/proc/base.c
> > > +++ b/fs/proc/base.c
> > > @@ -1299,6 +1299,41 @@ static ssize_t proc_sessionid_read(struct file
> > > * file, char __user * buf, .read = proc_sessionid_read,
> > > .llseek = generic_file_llseek,
> > > };
> > > +
> > > +static ssize_t proc_containerid_write(struct file *file, const char
> > > __user *buf,
> > > + size_t count, loff_t *ppos)
> > > +{
> > > + struct inode *inode = file_inode(file);
> > > + u64 containerid;
> > > + int rv;
> > > + struct task_struct *task = get_proc_task(inode);
> > > +
> > > + if (!task)
> > > + return -ESRCH;
> > > + if (*ppos != 0) {
> > > + /* No partial writes. */
> > > + put_task_struct(task);
> > > + return -EINVAL;
> > > + }
> > > +
> > > + rv = kstrtou64_from_user(buf, count, 10, &containerid);
> > > + if (rv < 0) {
> > > + put_task_struct(task);
> > > + return rv;
> > > + }
> > > +
> > > + rv = audit_set_containerid(task, containerid);
> > > + put_task_struct(task);
> > > + if (rv < 0)
> > > + return rv;
> > > + return count;
> > > +}
> > > +
> > > +static const struct file_operations proc_containerid_operations = {
> > > + .write = proc_containerid_write,
> > > + .llseek = generic_file_llseek,
> > > +};
> > > +
> > > #endif
> > >
> > > #ifdef CONFIG_FAULT_INJECTION
> > > @@ -2961,6 +2996,7 @@ static int proc_pid_patch_state(struct seq_file
> > > *m, struct pid_namespace *ns, #ifdef CONFIG_AUDITSYSCALL
> > > REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations),
> > > REG("sessionid", S_IRUGO, proc_sessionid_operations),
> > > + REG("containerid", S_IWUSR, proc_containerid_operations),
> > > #endif
> > > #ifdef CONFIG_FAULT_INJECTION
> > > REG("make-it-fail", S_IRUGO|S_IWUSR,
> > > proc_fault_inject_operations), @@ -3355,6 +3391,7 @@ static int
> > > proc_tid_comm_permission(struct inode *inode, int mask) #ifdef
> > > CONFIG_AUDITSYSCALL REG("loginuid", S_IWUSR|S_IRUGO,
> > > proc_loginuid_operations), REG("sessionid", S_IRUGO,
> > > proc_sessionid_operations),
> > > + REG("containerid", S_IWUSR, proc_containerid_operations),
> > > #endif
> > > #ifdef CONFIG_FAULT_INJECTION
> > > REG("make-it-fail", S_IRUGO|S_IWUSR,
> > > proc_fault_inject_operations), diff --git a/include/linux/audit.h
> > > b/include/linux/audit.h index af410d9..fe4ba3f 100644
> > > --- a/include/linux/audit.h
> > > +++ b/include/linux/audit.h
> > > @@ -29,6 +29,7 @@
> > >
> > > #define AUDIT_INO_UNSET ((unsigned long)-1)
> > > #define AUDIT_DEV_UNSET ((dev_t)-1)
> > > +#define INVALID_CID AUDIT_CID_UNSET
> > >
> > > struct audit_sig_info {
> > > uid_t uid;
> > > @@ -321,6 +322,7 @@ static inline void audit_ptrace(struct
> > > task_struct *t) extern int auditsc_get_stamp(struct audit_context
> > > *ctx, struct timespec64 *t, unsigned int *serial);
> > > extern int audit_set_loginuid(kuid_t loginuid);
> > > +extern int audit_set_containerid(struct task_struct *tsk, u64
> > > containerid);
> > > static inline kuid_t audit_get_loginuid(struct task_struct *tsk)
> > > {
> > > @@ -332,6 +334,11 @@ static inline unsigned int
> > > audit_get_sessionid(struct task_struct *tsk) return tsk->sessionid;
> > > }
> > >
> > > +static inline u64 audit_get_containerid(struct task_struct *tsk)
> > > +{
> > > + return tsk->containerid;
> > > +}
> > > +
> > > extern void __audit_ipc_obj(struct kern_ipc_perm *ipcp);
> > > extern void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid,
> > > gid_t gid, umode_t mode); extern void __audit_bprm(struct
> > > linux_binprm *bprm); @@ -517,6 +524,10 @@ static inline unsigned int
> > > audit_get_sessionid(struct task_struct *tsk) {
> > > return -1;
> > > }
> > > +static inline kuid_t audit_get_containerid(struct task_struct *tsk)
> > > +{
> > > + return INVALID_CID;
> > > +}
> > > static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
> > > { }
> > > static inline void audit_ipc_set_perm(unsigned long qbytes, uid_t
> > > uid, @@ -581,6 +592,11 @@ static inline bool
> > > audit_loginuid_set(struct task_struct *tsk) return
> > > uid_valid(audit_get_loginuid(tsk)); }
> > >
> > > +static inline bool audit_containerid_set(struct task_struct *tsk)
> > > +{
> > > + return audit_get_containerid(tsk) != INVALID_CID;
> > > +}
> > > +
> > > static inline void audit_log_string(struct audit_buffer *ab, const
> > > char *buf) {
> > > audit_log_n_string(ab, buf, strlen(buf));
> > > diff --git a/include/linux/init_task.h b/include/linux/init_task.h
> > > index 6a53262..046bd0a 100644
> > > --- a/include/linux/init_task.h
> > > +++ b/include/linux/init_task.h
> > > @@ -18,6 +18,7 @@
> > > #include <linux/sched/rt.h>
> > > #include <linux/livepatch.h>
> > > #include <linux/mm_types.h>
> > > +#include <linux/audit.h>
> > >
> > > #include <asm/thread_info.h>
> > >
> > > @@ -120,7 +121,8 @@
> > > #ifdef CONFIG_AUDITSYSCALL
> > > #define INIT_IDS \
> > > .loginuid = INVALID_UID, \
> > > - .sessionid = (unsigned int)-1,
> > > + .sessionid = (unsigned int)-1, \
> > > + .containerid = INVALID_CID,
> > > #else
> > > #define INIT_IDS
> > > #endif
> > > diff --git a/include/linux/sched.h b/include/linux/sched.h
> > > index d258826..1b82191 100644
> > > --- a/include/linux/sched.h
> > > +++ b/include/linux/sched.h
> > > @@ -796,6 +796,7 @@ struct task_struct {
> > > #ifdef CONFIG_AUDITSYSCALL
> > > kuid_t loginuid;
> > > unsigned int sessionid;
> > > + u64 containerid;
> > > #endif
> > > struct seccomp seccomp;
> > >
> > > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
> > > index 4e61a9e..921a71f 100644
> > > --- a/include/uapi/linux/audit.h
> > > +++ b/include/uapi/linux/audit.h
> > > @@ -71,6 +71,7 @@
> > > #define AUDIT_TTY_SET 1017 /* Set TTY auditing
> > > status */ #define AUDIT_SET_FEATURE 1018 /* Turn an
> > > audit feature on or off */ #define AUDIT_GET_FEATURE
> > > 1019 /* Get which features are enabled */ +#define
> > > AUDIT_CONTAINER 1020 /* Define the container id
> > > and information */ #define AUDIT_FIRST_USER_MSG 1100 /*
> > > Userspace messages mostly uninteresting to kernel */ #define
> > > AUDIT_USER_AVC 1107 /* We filter this
> > > differently */ @@ -465,6 +466,7 @@ struct audit_tty_status { };
> > >
> > > #define AUDIT_UID_UNSET (unsigned int)-1
> > > +#define AUDIT_CID_UNSET ((u64)-1)
> > >
> > > /* audit_rule_data supports filter rules with both integer and string
> > > * fields. It corresponds with AUDIT_ADD_RULE, AUDIT_DEL_RULE and
> > > diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> > > index 4e0a4ac..29c8482 100644
> > > --- a/kernel/auditsc.c
> > > +++ b/kernel/auditsc.c
> > > @@ -2073,6 +2073,90 @@ int audit_set_loginuid(kuid_t loginuid)
> > > return rc;
> > > }
> > >
> > > +static int audit_set_containerid_perm(struct task_struct *task, u64
> > > containerid) +{
> > > + struct task_struct *parent;
> > > + u64 pcontainerid, ccontainerid;
> > > +
> > > + /* Don't allow to set our own containerid */
> > > + if (current == task)
> > > + return -EPERM;
> > > + /* Don't allow the containerid to be unset */
> > > + if (!cid_valid(containerid))
> > > + return -EINVAL;
> > > + /* if we don't have caps, reject */
> > > + if (!capable(CAP_AUDIT_CONTROL))
> > > + return -EPERM;
> > > + /* if containerid is unset, allow */
> > > + if (!audit_containerid_set(task))
> > > + return 0;
> > > + /* it is already set, and not inherited from the parent,
> > > reject */
> > > + ccontainerid = audit_get_containerid(task);
> > > + rcu_read_lock();
> > > + parent = rcu_dereference(task->real_parent);
> > > + rcu_read_unlock();
> > > + task_lock(parent);
> > > + pcontainerid = audit_get_containerid(parent);
> > > + task_unlock(parent);
> > > + if (ccontainerid != pcontainerid)
> > > + return -EPERM;
> > > + return 0;
> > > +}
> > > +
> > > +static void audit_log_set_containerid(struct task_struct *task, u64
> > > oldcontainerid,
> > > + u64 containerid, int rc)
> > > +{
> > > + struct audit_buffer *ab;
> > > + uid_t uid;
> > > + struct tty_struct *tty;
> > > +
> > > + if (!audit_enabled)
> > > + return;
> > > +
> > > + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONTAINER);
> > > + if (!ab)
> > > + return;
> > > +
> > > + uid = from_kuid(&init_user_ns, task_uid(current));
> > > + tty = audit_get_tty(current);
> > > +
> > > + audit_log_format(ab, "op=set pid=%d uid=%u",
> > > task_tgid_nr(current), uid);
> > > + audit_log_task_context(ab);
> > > + audit_log_format(ab, " auid=%u tty=%s ses=%u opid=%d
> > > old-contid=%llu contid=%llu res=%d",
> >
> > The preferred ordering would be: op, opid, old-contid, contid, pid, uid,
> > tty, ses, subj, comm, exe, res. This groups the searchable fields
> > together using the most common ordering so that parsing is simple.
>
> Where would you like auid? It appears that just before uid would be the
> right place, if not in place of uid, but this is just a guess since it
> isn't consistent.
Just after the uid is the proper place. The most common sequence is:
pid, uid, auid, tty, session, subject context, comm, exe.
Thanks,
-Steve
^ permalink raw reply
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Matthew Wilcox @ 2018-06-04 17:16 UTC (permalink / raw)
To: Al Viro
Cc: David Howells, Christoph Hellwig, linux-fsdevel, linux-afs,
linux-kernel, linux-api
In-Reply-To: <20180603005532.GZ30522@ZenIV.linux.org.uk>
On Sun, Jun 03, 2018 at 01:55:37AM +0100, Al Viro wrote:
> +SYSCALL_DEFINE3(open_tree, int, dfd, const char *, filename, unsigned, flags)
> +{
> + struct file *file;
> + struct path path;
> + int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
> + bool detached = flags & OPEN_TREE_CLONE;
> + int error;
> + int fd;
> +
> + BUILD_BUG_ON(OPEN_TREE_CLOEXEC != O_CLOEXEC);
Why do we need OPEN_TREE_CLOEXEC? Wouldn't we be better off just making
the fd returned by open_tree implicitly close-on-exec? I can think of
no good reason for these file descriptors to be inherited across exec()
and if someone comes up with such a reason, fcntl(F_SETFD) is not an
expensive call to make.
^ permalink raw reply
* Re: [PATCH][RFC] open_tree(2) (was Re: [PATCH 30/32] vfs: Allow cloning of a mount tree with open(O_PATH|O_CLONE_MOUNT) [ver #8])
From: Al Viro @ 2018-06-04 17:35 UTC (permalink / raw)
To: Matthew Wilcox
Cc: David Howells, Christoph Hellwig, linux-fsdevel, linux-afs,
linux-kernel, linux-api
In-Reply-To: <20180604171630.GA29059@bombadil.infradead.org>
On Mon, Jun 04, 2018 at 10:16:30AM -0700, Matthew Wilcox wrote:
> On Sun, Jun 03, 2018 at 01:55:37AM +0100, Al Viro wrote:
> > +SYSCALL_DEFINE3(open_tree, int, dfd, const char *, filename, unsigned, flags)
> > +{
> > + struct file *file;
> > + struct path path;
> > + int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
> > + bool detached = flags & OPEN_TREE_CLONE;
> > + int error;
> > + int fd;
> > +
> > + BUILD_BUG_ON(OPEN_TREE_CLOEXEC != O_CLOEXEC);
>
> Why do we need OPEN_TREE_CLOEXEC? Wouldn't we be better off just making
> the fd returned by open_tree implicitly close-on-exec? I can think of
> no good reason for these file descriptors to be inherited across exec()
How are they different from any file descriptor? It's not as if it was
something usable only for mounting stuff - again, you can use them
with any ...at() syscalls.
> and if someone comes up with such a reason, fcntl(F_SETFD) is not an
> expensive call to make.
^ permalink raw reply
* [PATCH 1/2] fs: aio ioprio add explicit block layer dependence
From: adam.manzanares @ 2018-06-04 17:59 UTC (permalink / raw)
To: viro, linux-fsdevel
Cc: axboe, bcrl, mingo, tglx, kstewart, peterz, pombredanne, gregkh,
bigeasy, rgoldwyn, linux-block, linux-kernel, linux-aio,
linux-api, hch, jmoyer, willy, smfrench, Adam Manzanares
From: Adam Manzanares <adam.manzanares@wdc.com>
Previously, the ioprio_check_cap function was only defined when CONFIG_BLOCK
was set. Make this relationship explicit and add a stub for !CONFIG_BLOCK.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
include/linux/ioprio.h | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h
index 4a28cec49ec3..9e30ed6443db 100644
--- a/include/linux/ioprio.h
+++ b/include/linux/ioprio.h
@@ -77,6 +77,13 @@ extern int ioprio_best(unsigned short aprio, unsigned short bprio);
extern int set_task_ioprio(struct task_struct *task, int ioprio);
+#ifdef CONFIG_BLOCK
extern int ioprio_check_cap(int ioprio);
+#else
+static inline int ioprio_check_cap(int ioprio)
+{
+ return -ENOTBLK;
+}
+#endif /* CONFIG_BLOCK */
#endif
--
2.17.0
--
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the body to majordomo@kvack.org. For more info on Linux AIO,
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^ permalink raw reply related
* [PATCH 2/2] fs: aio ioprio use ioprio_check_cap ret val
From: adam.manzanares @ 2018-06-04 17:59 UTC (permalink / raw)
To: viro, linux-fsdevel
Cc: axboe, bcrl, mingo, tglx, kstewart, peterz, pombredanne, gregkh,
bigeasy, rgoldwyn, linux-block, linux-kernel, linux-aio,
linux-api, hch, jmoyer, willy, smfrench, Adam Manzanares
In-Reply-To: <20180604175957.2647-1-adam.manzanares@wdc.com>
From: Adam Manzanares <adam.manzanares@wdc.com>
Previously the value was ignored.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
fs/aio.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/aio.c b/fs/aio.c
index 9527ededa669..134e5b635d64 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1443,8 +1443,8 @@ static int aio_prep_rw(struct kiocb *req, struct iocb *iocb)
*/
ret = ioprio_check_cap(iocb->aio_reqprio);
if (ret) {
- pr_debug("aio ioprio check cap error\n");
- return -EINVAL;
+ pr_debug("aio ioprio check cap error: %d\n", ret);
+ return ret;
}
req->ki_ioprio = iocb->aio_reqprio;
--
2.17.0
--
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the body to majordomo@kvack.org. For more info on Linux AIO,
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^ permalink raw reply related
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