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* [GIT PULL] Please pull powerpc/linux.git powerpc-4.16-3 tag
From: Michael Ellerman @ 2018-02-17  9:45 UTC (permalink / raw)
  To: Linus Torvalds
  Cc: clabbe, clg, cyrilbur, linux-kernel, linuxppc-dev, nfont, npiggin

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Hi Linus,

Please pull some more powerpc fixes for 4.16. Sorry to send a pull
request on the weekend, and a 2nd one this week, but one of these
commits fixes a boot crash which would be good to get in before rc2.

cheers

The following changes since commit 694a20dae6efc3803740971fa9f7c86b8c8d4685:

  Merge tag 'powerpc-4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux (2018-02-14 10:06:41 -0800)

are available in the git repository at:

  https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git tags/powerpc-4.16-3

for you to fetch changes up to 2c10636a0b9c689450e85f9945583920f50337c9:

  powerpc/pseries: Check for zero filled ibm,dynamic-memory property (2018-02-16 21:34:14 +1100)

----------------------------------------------------------------
powerpc fixes for 4.16 #3

The main attraction is a fix for a bug in the new drmem code, which was causing
an oops on boot on some versions of Qemu.

There's also a fix for XIVE (Power9 interrupt controller) on KVM, as well as a
few other minor fixes.

Thanks to:
  Corentin Labbe, Cyril Bur, Cédric Le Goater, Daniel Black, Nathan Fontenot,
  Nicholas Piggin.

----------------------------------------------------------------
Corentin Labbe (1):
      powerpc/pseries: Add empty update_numa_cpu_lookup_table() for NUMA=n

Cyril Bur (1):
      powerpc: Expose TSCR via sysfs only on powernv

Cédric Le Goater (1):
      powerpc/xive: Use hw CPU ids when configuring the CPU queues

Nathan Fontenot (1):
      powerpc/pseries: Check for zero filled ibm,dynamic-memory property

Nicholas Piggin (1):
      powerpc/powernv: IMC fix out of bounds memory access at shutdown

 arch/powerpc/include/asm/topology.h       |  3 +++
 arch/powerpc/kernel/sysfs.c               |  6 ++++--
 arch/powerpc/mm/drmem.c                   |  8 ++++++++
 arch/powerpc/platforms/powernv/opal-imc.c |  6 ++++--
 arch/powerpc/sysdev/xive/spapr.c          | 16 ++++++++++------
 5 files changed, 29 insertions(+), 10 deletions(-)

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^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Ravi Bangoria @ 2018-02-17  6:17 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe, Ravi Bangoria
In-Reply-To: <20180216175002.GC16919@kernel.org>

Oops.. Really sorry about that.

I've tested acme/perf/core on ubuntu ppc32 with and without libaudit-dev
and it's working fine.

Thank you very much for fixing it,
Ravi

On 02/16/2018 11:20 PM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Feb 16, 2018 at 02:29:01PM -0300, Arnaldo Carvalho de Melo escreveu:
>> Humm, we need to create two tables, one for 32-bit and another for 64,
>> even with ppc not having (AFAIK) clashes in syscall numbers for 32/64...
>>
>> Trying to do it now.
> Now seems to work, take a look at my perf/core branch, should be one of the first few csets.
>
> perfbuilder@cc1a85517216:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_32.c 
> 	[192] = "mmap2",
> perfbuilder@cc1a85517216:/git/perf$ powerpc-linux-gnu-gcc --version
> powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> perfbuilder@cc1a85517216:/git/perf$
>
> perfbuilder@9d7fc9dcfb73:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_32.c
> 	[192] = "mmap2",
> perfbuilder@9d7fc9dcfb73:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_64.c
> perfbuilder@9d7fc9dcfb73:/git/perf$ powerpc64-linux-gnu-gcc --version
> powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
> perfbuilder@9d7fc9dcfb73:/git/perf$ 
>

^ permalink raw reply

* [PATCH RESEND] powerpc/5200: dts: digsy_mtc.dts: fix rv3029 compatible
From: Alexandre Belloni @ 2018-02-16 23:43 UTC (permalink / raw)
  To: Michael Ellerman; +Cc: linuxppc-dev, linux-rtc, linux-kernel, Alexandre Belloni

The proper compatible for rv3029 is microcrystal,rv3029.

Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---

Hi,

I'm resending that one because I prefer not taking DT patches through the RTC
tree.

 arch/powerpc/boot/dts/digsy_mtc.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/boot/dts/digsy_mtc.dts b/arch/powerpc/boot/dts/digsy_mtc.dts
index c280e75c86bf..c3922fc03e0b 100644
--- a/arch/powerpc/boot/dts/digsy_mtc.dts
+++ b/arch/powerpc/boot/dts/digsy_mtc.dts
@@ -78,7 +78,7 @@
 			};
 
 			rtc@56 {
-				compatible = "mc,rv3029c2";
+				compatible = "microcrystal,rv3029";
 				reg = <0x56>;
 			};
 
-- 
2.16.1

^ permalink raw reply related

* [PATCH 35/41] perf trace powerpc: Use generated syscall table
From: Arnaldo Carvalho de Melo @ 2018-02-16 19:17 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: linux-kernel, linux-perf-users, Ravi Bangoria, Alexander Shishkin,
	Hendrik Brueckner, Jiri Olsa, Michael Ellerman, Namhyung Kim,
	Thomas Richter, linuxppc-dev, Arnaldo Carvalho de Melo
In-Reply-To: <20180216191746.11095-1-acme@kernel.org>

From: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>

This should speed up accessing new system calls introduced with the
kernel rather than waiting for libaudit updates to include them.

It also enables users to specify wildcards, for example, perf trace -e
'open*', just like was already possible on x86 and s390.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20180129083417.31240-4-ravi.bangoria@linux.vnet.ibm.com
[ Do it for ppc32 as well ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/Makefile.config   | 2 ++
 tools/perf/util/syscalltbl.c | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 0dfdaa9fa81e..577a5d2988fe 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -27,6 +27,8 @@ NO_SYSCALL_TABLE := 1
 # Additional ARCH settings for ppc
 ifeq ($(SRCARCH),powerpc)
   NO_PERF_REGS := 0
+  NO_SYSCALL_TABLE := 0
+  CFLAGS += -I$(OUTPUT)arch/powerpc/include/generated
   LIBUNWIND_LIBS := -lunwind -lunwind-ppc64
 endif
 
diff --git a/tools/perf/util/syscalltbl.c b/tools/perf/util/syscalltbl.c
index 303bdb84ab5a..895122d638dd 100644
--- a/tools/perf/util/syscalltbl.c
+++ b/tools/perf/util/syscalltbl.c
@@ -30,6 +30,14 @@ static const char **syscalltbl_native = syscalltbl_x86_64;
 #include <asm/syscalls_64.c>
 const int syscalltbl_native_max_id = SYSCALLTBL_S390_64_MAX_ID;
 static const char **syscalltbl_native = syscalltbl_s390_64;
+#elif defined(__powerpc64__)
+#include <asm/syscalls_64.c>
+const int syscalltbl_native_max_id = SYSCALLTBL_POWERPC_64_MAX_ID;
+static const char **syscalltbl_native = syscalltbl_powerpc_64;
+#elif defined(__powerpc__)
+#include <asm/syscalls_32.c>
+const int syscalltbl_native_max_id = SYSCALLTBL_POWERPC_32_MAX_ID;
+static const char **syscalltbl_native = syscalltbl_powerpc_32;
 #endif
 
 struct syscall {
-- 
2.14.3

^ permalink raw reply related

* [PATCH 34/41] perf powerpc: Generate system call table from asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 19:17 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: linux-kernel, linux-perf-users, Ravi Bangoria, Alexander Shishkin,
	Hendrik Brueckner, Jiri Olsa, Michael Ellerman, Namhyung Kim,
	Thomas Richter, linuxppc-dev, Arnaldo Carvalho de Melo
In-Reply-To: <20180216191746.11095-1-acme@kernel.org>

From: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>

This should speed up accessing new system calls introduced with the
kernel rather than waiting for libaudit updates to include them.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20180129083417.31240-3-ravi.bangoria@linux.vnet.ibm.com
[ Made it generate syscall_32.c as well to fix the build on 32-bit ppc ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/arch/powerpc/Makefile                   | 25 +++++++++++++++
 .../perf/arch/powerpc/entry/syscalls/mksyscalltbl  | 37 ++++++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100755 tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl

diff --git a/tools/perf/arch/powerpc/Makefile b/tools/perf/arch/powerpc/Makefile
index 42dab7c8f508..a111239df182 100644
--- a/tools/perf/arch/powerpc/Makefile
+++ b/tools/perf/arch/powerpc/Makefile
@@ -6,3 +6,28 @@ endif
 HAVE_KVM_STAT_SUPPORT := 1
 PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
 PERF_HAVE_JITDUMP := 1
+
+#
+# Syscall table generation for perf
+#
+
+out    := $(OUTPUT)arch/powerpc/include/generated/asm
+header32 := $(out)/syscalls_32.c
+header64 := $(out)/syscalls_64.c
+sysdef := $(srctree)/tools/arch/powerpc/include/uapi/asm/unistd.h
+sysprf := $(srctree)/tools/perf/arch/powerpc/entry/syscalls/
+systbl := $(sysprf)/mksyscalltbl
+
+# Create output directory if not already present
+_dummy := $(shell [ -d '$(out)' ] || mkdir -p '$(out)')
+
+$(header64): $(sysdef) $(systbl)
+	$(Q)$(SHELL) '$(systbl)' '64' '$(CC)' $(sysdef) > $@
+
+$(header32): $(sysdef) $(systbl)
+	$(Q)$(SHELL) '$(systbl)' '32' '$(CC)' $(sysdef) > $@
+
+clean::
+	$(call QUIET_CLEAN, powerpc) $(RM) $(header32) $(header64)
+
+archheaders: $(header32) $(header64)
diff --git a/tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl b/tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl
new file mode 100755
index 000000000000..ef52e1dd694b
--- /dev/null
+++ b/tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl
@@ -0,0 +1,37 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Generate system call table for perf. Derived from
+# s390 script.
+#
+# Copyright IBM Corp. 2017
+# Author(s):  Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+# Changed by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
+
+wordsize=$1
+gcc=$2
+input=$3
+
+if ! test -r $input; then
+	echo "Could not read input file" >&2
+	exit 1
+fi
+
+create_table()
+{
+	local wordsize=$1
+	local max_nr
+
+	echo "static const char *syscalltbl_powerpc_${wordsize}[] = {"
+	while read sc nr; do
+		printf '\t[%d] = "%s",\n' $nr $sc
+		max_nr=$nr
+	done
+	echo '};'
+	echo "#define SYSCALLTBL_POWERPC_${wordsize}_MAX_ID $max_nr"
+}
+
+$gcc -m${wordsize} -E -dM -x c  $input	       \
+	|sed -ne 's/^#define __NR_//p' \
+	|sort -t' ' -k2 -nu	       \
+	|create_table ${wordsize}
-- 
2.14.3

^ permalink raw reply related

* [PATCH 33/41] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 19:17 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: linux-kernel, linux-perf-users, Ravi Bangoria, Alexander Shishkin,
	Hendrik Brueckner, Jiri Olsa, Michael Ellerman, Namhyung Kim,
	Thomas Richter, linuxppc-dev, Arnaldo Carvalho de Melo
In-Reply-To: <20180216191746.11095-1-acme@kernel.org>

From: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>

Will be used for generating the syscall id/string translation table.

Committer notes:

Update it already to catch with these csets applied since Ravi first
submitted this patch:

  3350eb2ea127 powerpc: sys_pkey_mprotect() system call
  9499ec1b5e82 powerpc: sys_pkey_alloc() and sys_pkey_free() system calls

So now 'perf trace' on ppc now knows about the pkey_ syscals.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Richter <tmricht@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20180129083417.31240-2-ravi.bangoria@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/arch/powerpc/include/uapi/asm/unistd.h | 402 +++++++++++++++++++++++++++
 tools/perf/check-headers.sh                  |   1 +
 2 files changed, 403 insertions(+)
 create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h

diff --git a/tools/arch/powerpc/include/uapi/asm/unistd.h b/tools/arch/powerpc/include/uapi/asm/unistd.h
new file mode 100644
index 000000000000..389c36fd8299
--- /dev/null
+++ b/tools/arch/powerpc/include/uapi/asm/unistd.h
@@ -0,0 +1,402 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * This file contains the system call numbers.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _UAPI_ASM_POWERPC_UNISTD_H_
+#define _UAPI_ASM_POWERPC_UNISTD_H_
+
+
+#define __NR_restart_syscall	  0
+#define __NR_exit		  1
+#define __NR_fork		  2
+#define __NR_read		  3
+#define __NR_write		  4
+#define __NR_open		  5
+#define __NR_close		  6
+#define __NR_waitpid		  7
+#define __NR_creat		  8
+#define __NR_link		  9
+#define __NR_unlink		 10
+#define __NR_execve		 11
+#define __NR_chdir		 12
+#define __NR_time		 13
+#define __NR_mknod		 14
+#define __NR_chmod		 15
+#define __NR_lchown		 16
+#define __NR_break		 17
+#define __NR_oldstat		 18
+#define __NR_lseek		 19
+#define __NR_getpid		 20
+#define __NR_mount		 21
+#define __NR_umount		 22
+#define __NR_setuid		 23
+#define __NR_getuid		 24
+#define __NR_stime		 25
+#define __NR_ptrace		 26
+#define __NR_alarm		 27
+#define __NR_oldfstat		 28
+#define __NR_pause		 29
+#define __NR_utime		 30
+#define __NR_stty		 31
+#define __NR_gtty		 32
+#define __NR_access		 33
+#define __NR_nice		 34
+#define __NR_ftime		 35
+#define __NR_sync		 36
+#define __NR_kill		 37
+#define __NR_rename		 38
+#define __NR_mkdir		 39
+#define __NR_rmdir		 40
+#define __NR_dup		 41
+#define __NR_pipe		 42
+#define __NR_times		 43
+#define __NR_prof		 44
+#define __NR_brk		 45
+#define __NR_setgid		 46
+#define __NR_getgid		 47
+#define __NR_signal		 48
+#define __NR_geteuid		 49
+#define __NR_getegid		 50
+#define __NR_acct		 51
+#define __NR_umount2		 52
+#define __NR_lock		 53
+#define __NR_ioctl		 54
+#define __NR_fcntl		 55
+#define __NR_mpx		 56
+#define __NR_setpgid		 57
+#define __NR_ulimit		 58
+#define __NR_oldolduname	 59
+#define __NR_umask		 60
+#define __NR_chroot		 61
+#define __NR_ustat		 62
+#define __NR_dup2		 63
+#define __NR_getppid		 64
+#define __NR_getpgrp		 65
+#define __NR_setsid		 66
+#define __NR_sigaction		 67
+#define __NR_sgetmask		 68
+#define __NR_ssetmask		 69
+#define __NR_setreuid		 70
+#define __NR_setregid		 71
+#define __NR_sigsuspend		 72
+#define __NR_sigpending		 73
+#define __NR_sethostname	 74
+#define __NR_setrlimit		 75
+#define __NR_getrlimit		 76
+#define __NR_getrusage		 77
+#define __NR_gettimeofday	 78
+#define __NR_settimeofday	 79
+#define __NR_getgroups		 80
+#define __NR_setgroups		 81
+#define __NR_select		 82
+#define __NR_symlink		 83
+#define __NR_oldlstat		 84
+#define __NR_readlink		 85
+#define __NR_uselib		 86
+#define __NR_swapon		 87
+#define __NR_reboot		 88
+#define __NR_readdir		 89
+#define __NR_mmap		 90
+#define __NR_munmap		 91
+#define __NR_truncate		 92
+#define __NR_ftruncate		 93
+#define __NR_fchmod		 94
+#define __NR_fchown		 95
+#define __NR_getpriority	 96
+#define __NR_setpriority	 97
+#define __NR_profil		 98
+#define __NR_statfs		 99
+#define __NR_fstatfs		100
+#define __NR_ioperm		101
+#define __NR_socketcall		102
+#define __NR_syslog		103
+#define __NR_setitimer		104
+#define __NR_getitimer		105
+#define __NR_stat		106
+#define __NR_lstat		107
+#define __NR_fstat		108
+#define __NR_olduname		109
+#define __NR_iopl		110
+#define __NR_vhangup		111
+#define __NR_idle		112
+#define __NR_vm86		113
+#define __NR_wait4		114
+#define __NR_swapoff		115
+#define __NR_sysinfo		116
+#define __NR_ipc		117
+#define __NR_fsync		118
+#define __NR_sigreturn		119
+#define __NR_clone		120
+#define __NR_setdomainname	121
+#define __NR_uname		122
+#define __NR_modify_ldt		123
+#define __NR_adjtimex		124
+#define __NR_mprotect		125
+#define __NR_sigprocmask	126
+#define __NR_create_module	127
+#define __NR_init_module	128
+#define __NR_delete_module	129
+#define __NR_get_kernel_syms	130
+#define __NR_quotactl		131
+#define __NR_getpgid		132
+#define __NR_fchdir		133
+#define __NR_bdflush		134
+#define __NR_sysfs		135
+#define __NR_personality	136
+#define __NR_afs_syscall	137 /* Syscall for Andrew File System */
+#define __NR_setfsuid		138
+#define __NR_setfsgid		139
+#define __NR__llseek		140
+#define __NR_getdents		141
+#define __NR__newselect		142
+#define __NR_flock		143
+#define __NR_msync		144
+#define __NR_readv		145
+#define __NR_writev		146
+#define __NR_getsid		147
+#define __NR_fdatasync		148
+#define __NR__sysctl		149
+#define __NR_mlock		150
+#define __NR_munlock		151
+#define __NR_mlockall		152
+#define __NR_munlockall		153
+#define __NR_sched_setparam		154
+#define __NR_sched_getparam		155
+#define __NR_sched_setscheduler		156
+#define __NR_sched_getscheduler		157
+#define __NR_sched_yield		158
+#define __NR_sched_get_priority_max	159
+#define __NR_sched_get_priority_min	160
+#define __NR_sched_rr_get_interval	161
+#define __NR_nanosleep		162
+#define __NR_mremap		163
+#define __NR_setresuid		164
+#define __NR_getresuid		165
+#define __NR_query_module	166
+#define __NR_poll		167
+#define __NR_nfsservctl		168
+#define __NR_setresgid		169
+#define __NR_getresgid		170
+#define __NR_prctl		171
+#define __NR_rt_sigreturn	172
+#define __NR_rt_sigaction	173
+#define __NR_rt_sigprocmask	174
+#define __NR_rt_sigpending	175
+#define __NR_rt_sigtimedwait	176
+#define __NR_rt_sigqueueinfo	177
+#define __NR_rt_sigsuspend	178
+#define __NR_pread64		179
+#define __NR_pwrite64		180
+#define __NR_chown		181
+#define __NR_getcwd		182
+#define __NR_capget		183
+#define __NR_capset		184
+#define __NR_sigaltstack	185
+#define __NR_sendfile		186
+#define __NR_getpmsg		187	/* some people actually want streams */
+#define __NR_putpmsg		188	/* some people actually want streams */
+#define __NR_vfork		189
+#define __NR_ugetrlimit		190	/* SuS compliant getrlimit */
+#define __NR_readahead		191
+#ifndef __powerpc64__			/* these are 32-bit only */
+#define __NR_mmap2		192
+#define __NR_truncate64		193
+#define __NR_ftruncate64	194
+#define __NR_stat64		195
+#define __NR_lstat64		196
+#define __NR_fstat64		197
+#endif
+#define __NR_pciconfig_read	198
+#define __NR_pciconfig_write	199
+#define __NR_pciconfig_iobase	200
+#define __NR_multiplexer	201
+#define __NR_getdents64		202
+#define __NR_pivot_root		203
+#ifndef __powerpc64__
+#define __NR_fcntl64		204
+#endif
+#define __NR_madvise		205
+#define __NR_mincore		206
+#define __NR_gettid		207
+#define __NR_tkill		208
+#define __NR_setxattr		209
+#define __NR_lsetxattr		210
+#define __NR_fsetxattr		211
+#define __NR_getxattr		212
+#define __NR_lgetxattr		213
+#define __NR_fgetxattr		214
+#define __NR_listxattr		215
+#define __NR_llistxattr		216
+#define __NR_flistxattr		217
+#define __NR_removexattr	218
+#define __NR_lremovexattr	219
+#define __NR_fremovexattr	220
+#define __NR_futex		221
+#define __NR_sched_setaffinity	222
+#define __NR_sched_getaffinity	223
+/* 224 currently unused */
+#define __NR_tuxcall		225
+#ifndef __powerpc64__
+#define __NR_sendfile64		226
+#endif
+#define __NR_io_setup		227
+#define __NR_io_destroy		228
+#define __NR_io_getevents	229
+#define __NR_io_submit		230
+#define __NR_io_cancel		231
+#define __NR_set_tid_address	232
+#define __NR_fadvise64		233
+#define __NR_exit_group		234
+#define __NR_lookup_dcookie	235
+#define __NR_epoll_create	236
+#define __NR_epoll_ctl		237
+#define __NR_epoll_wait		238
+#define __NR_remap_file_pages	239
+#define __NR_timer_create	240
+#define __NR_timer_settime	241
+#define __NR_timer_gettime	242
+#define __NR_timer_getoverrun	243
+#define __NR_timer_delete	244
+#define __NR_clock_settime	245
+#define __NR_clock_gettime	246
+#define __NR_clock_getres	247
+#define __NR_clock_nanosleep	248
+#define __NR_swapcontext	249
+#define __NR_tgkill		250
+#define __NR_utimes		251
+#define __NR_statfs64		252
+#define __NR_fstatfs64		253
+#ifndef __powerpc64__
+#define __NR_fadvise64_64	254
+#endif
+#define __NR_rtas		255
+#define __NR_sys_debug_setcontext 256
+/* Number 257 is reserved for vserver */
+#define __NR_migrate_pages	258
+#define __NR_mbind		259
+#define __NR_get_mempolicy	260
+#define __NR_set_mempolicy	261
+#define __NR_mq_open		262
+#define __NR_mq_unlink		263
+#define __NR_mq_timedsend	264
+#define __NR_mq_timedreceive	265
+#define __NR_mq_notify		266
+#define __NR_mq_getsetattr	267
+#define __NR_kexec_load		268
+#define __NR_add_key		269
+#define __NR_request_key	270
+#define __NR_keyctl		271
+#define __NR_waitid		272
+#define __NR_ioprio_set		273
+#define __NR_ioprio_get		274
+#define __NR_inotify_init	275
+#define __NR_inotify_add_watch	276
+#define __NR_inotify_rm_watch	277
+#define __NR_spu_run		278
+#define __NR_spu_create		279
+#define __NR_pselect6		280
+#define __NR_ppoll		281
+#define __NR_unshare		282
+#define __NR_splice		283
+#define __NR_tee		284
+#define __NR_vmsplice		285
+#define __NR_openat		286
+#define __NR_mkdirat		287
+#define __NR_mknodat		288
+#define __NR_fchownat		289
+#define __NR_futimesat		290
+#ifdef __powerpc64__
+#define __NR_newfstatat		291
+#else
+#define __NR_fstatat64		291
+#endif
+#define __NR_unlinkat		292
+#define __NR_renameat		293
+#define __NR_linkat		294
+#define __NR_symlinkat		295
+#define __NR_readlinkat		296
+#define __NR_fchmodat		297
+#define __NR_faccessat		298
+#define __NR_get_robust_list	299
+#define __NR_set_robust_list	300
+#define __NR_move_pages		301
+#define __NR_getcpu		302
+#define __NR_epoll_pwait	303
+#define __NR_utimensat		304
+#define __NR_signalfd		305
+#define __NR_timerfd_create	306
+#define __NR_eventfd		307
+#define __NR_sync_file_range2	308
+#define __NR_fallocate		309
+#define __NR_subpage_prot	310
+#define __NR_timerfd_settime	311
+#define __NR_timerfd_gettime	312
+#define __NR_signalfd4		313
+#define __NR_eventfd2		314
+#define __NR_epoll_create1	315
+#define __NR_dup3		316
+#define __NR_pipe2		317
+#define __NR_inotify_init1	318
+#define __NR_perf_event_open	319
+#define __NR_preadv		320
+#define __NR_pwritev		321
+#define __NR_rt_tgsigqueueinfo	322
+#define __NR_fanotify_init	323
+#define __NR_fanotify_mark	324
+#define __NR_prlimit64		325
+#define __NR_socket		326
+#define __NR_bind		327
+#define __NR_connect		328
+#define __NR_listen		329
+#define __NR_accept		330
+#define __NR_getsockname	331
+#define __NR_getpeername	332
+#define __NR_socketpair		333
+#define __NR_send		334
+#define __NR_sendto		335
+#define __NR_recv		336
+#define __NR_recvfrom		337
+#define __NR_shutdown		338
+#define __NR_setsockopt		339
+#define __NR_getsockopt		340
+#define __NR_sendmsg		341
+#define __NR_recvmsg		342
+#define __NR_recvmmsg		343
+#define __NR_accept4		344
+#define __NR_name_to_handle_at	345
+#define __NR_open_by_handle_at	346
+#define __NR_clock_adjtime	347
+#define __NR_syncfs		348
+#define __NR_sendmmsg		349
+#define __NR_setns		350
+#define __NR_process_vm_readv	351
+#define __NR_process_vm_writev	352
+#define __NR_finit_module	353
+#define __NR_kcmp		354
+#define __NR_sched_setattr	355
+#define __NR_sched_getattr	356
+#define __NR_renameat2		357
+#define __NR_seccomp		358
+#define __NR_getrandom		359
+#define __NR_memfd_create	360
+#define __NR_bpf		361
+#define __NR_execveat		362
+#define __NR_switch_endian	363
+#define __NR_userfaultfd	364
+#define __NR_membarrier		365
+#define __NR_mlock2		378
+#define __NR_copy_file_range	379
+#define __NR_preadv2		380
+#define __NR_pwritev2		381
+#define __NR_kexec_file_load	382
+#define __NR_statx		383
+#define __NR_pkey_alloc		384
+#define __NR_pkey_free		385
+#define __NR_pkey_mprotect	386
+
+#endif /* _UAPI_ASM_POWERPC_UNISTD_H_ */
diff --git a/tools/perf/check-headers.sh b/tools/perf/check-headers.sh
index 790ec25919a0..bf206ffe5c45 100755
--- a/tools/perf/check-headers.sh
+++ b/tools/perf/check-headers.sh
@@ -42,6 +42,7 @@ arch/parisc/include/uapi/asm/errno.h
 arch/powerpc/include/uapi/asm/errno.h
 arch/sparc/include/uapi/asm/errno.h
 arch/x86/include/uapi/asm/errno.h
+arch/powerpc/include/uapi/asm/unistd.h
 include/asm-generic/bitops/arch_hweight.h
 include/asm-generic/bitops/const_hweight.h
 include/asm-generic/bitops/__fls.h
-- 
2.14.3

^ permalink raw reply related

* [GIT PULL 00/41] perf/core improvements and fixes
From: Arnaldo Carvalho de Melo @ 2018-02-16 19:17 UTC (permalink / raw)
  To: Ingo Molnar
  Cc: linux-kernel, linux-perf-users, Arnaldo Carvalho de Melo,
	Adrian Hunter, Alexander Shishkin, Andi Kleen, coresight,
	David Ahern, Heiko Carstens, Hendrik Brueckner, Jaecheol Shin,
	Jin Yao, Jiri Olsa, Kan Liang, linux-arm-kernel, linuxppc-dev,
	Martin Schwidefsky, Masami Hiramatsu, Mathieu Poirier,
	Michael Ellerman, Milian Wolff, Namhyung Kim, Naveen N . Rao,
	Peter Zijlstra, Ravi Bangoria, Robert Walker, Sangwon Hong,
	Stephane Eranian, Taeung Song, Thomas Richter, Wang Nan,
	yuzhoujian, Arnaldo Carvalho de Melo

Hi Ingo,

	Please consider pulling, this is on top of tip/perf/urgent.

- Arnaldo

Test results at the end of this message, as usual.

The following changes since commit 297f9233b53a08fd457815e19f1d6f2c3389857b:

  kprobes: Propagate error from disarm_kprobe_ftrace() (2018-02-16 09:12:58 +0100)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git tags/perf-core-for-mingo-4.17-20180216

for you to fetch changes up to 21316ac6803d4a1aadd74b896db8d60a92cd1140:

  perf tests shell lib: Use a wildcard to remove the vfs_getname probe (2018-02-16 15:31:12 -0300)

----------------------------------------------------------------
perf/core improvements and fixes:

- Fix wrong jump arrow in systems with branch records with cycles,
  i.e. Intel's >= Skylake (Jin Yao)

- Fix 'perf record --per-thread' problem introduced when
  implementing 'perf stat --per-thread (Jin Yao)

- Use arch__compare_symbol_names() to fix 'perf test vmlinux',
  that was using strcmp(symbol names) while the dso routines
  doing symbol lookups used the arch overridable one, making
  this test fail in architectures that overrided that function
  with something other than strcmp() (Jiri Olsa)

- Add 'perf script --show-round-event' to display
  PERF_RECORD_FINISHED_ROUND entries (Jiri Olsa)

- Fix dwarf unwind for stripped binaries in 'perf test' (Jiri Olsa)

- Use ordered_events for 'perf report --tasks', otherwise we may get
  artifacts when PERF_RECORD_FORK gets processed before PERF_RECORD_COMM
  (when they got recorded in different CPUs) (Jiri Olsa)

- Add support to display group output for non group events, i.e.
  now when one uses 'perf report --group' on a perf.data file
  recorded without explicitly grouping events with {} (e.g.
  "perf record -e '{cycles,instructions}'" get the same output
  that would produce, i.e. see all those non-grouped events in
  multiple columns, at the same time (Jiri Olsa)

- Skip non-address kallsyms entries, e.g. '(null)' for !root (Jiri Olsa)

- Kernel maps fixes wrt perf.data(report) versus live system (top)
  (Jiri Olsa)

- Fix memory corruption when using 'perf record -j call -g -a <application>'
  followed by 'perf report --branch-history' (Jiri Olsa)

- ARM CoreSight fixes (Mathieu Poirier)

- Add inject capability for CoreSight Traces (Robert Waker)

- Update documentation for use of 'perf' + ARM CoreSight (Robert Walker)

- Man pages fixes (Sangwon Hong, Jaecheol Shin)

- Fix some 'perf test' cases on s/390 and x86_64 (some backtraces
  changed with a glibc update) (Thomas Richter)

- Add detailed CPUID info in the 'perf.data' headers for s/390 to
  then use it in 'perf annotate' (Thomas Richter)

- Add '--interval-count N' to 'perf stat', to use with -I, i.e.
  'perf stat -I 1000 --interval-count 2' will show stats every
   1000ms, two times (yuzhoujian)

- Add 'perf stat --timeout Nms', that will run for that many
  milliseconds and then stop, printing the counters (yuzhoujian)

- Fix description for 'perf report --mem-modex (Andi Kleen)

- Use a wildcard to remove the vfs_getname probe in the
  'perf test' shell based test cases (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

----------------------------------------------------------------
Andi Kleen (1):
      perf report: Fix description for --mem-mode

Arnaldo Carvalho de Melo (1):
      perf tests shell lib: Use a wildcard to remove the vfs_getname probe

Jaecheol Shin (1):
      perf annotate: Add missing arguments in Man page

Jin Yao (2):
      perf tools: Use target->per_thread and target->system_wide flags
      perf report: Fix wrong jump arrow

Jiri Olsa (18):
      perf record: Put new line after target override warning
      perf script: Add --show-round-event to display PERF_RECORD_FINISHED_ROUND
      tools lib api fs: Add filename__read_xll function
      tools lib api fs: Add sysfs__read_xll function
      perf tests: Fix dwarf unwind for stripped binaries
      perf tools: Fix comment for sort__* compare functions
      perf report: Ask for ordered events for --tasks option
      perf report: Add support to display group output for non group events
      tools lib symbol: Skip non-address kallsyms line
      perf symbols: Check if we read regular file in dso__load()
      perf machine: Free root_dir in machine__init() error path
      perf machine: Move kernel mmap name into struct machine
      perf machine: Generalize machine__set_kernel_mmap()
      perf machine: Don't search for active kernel start in __machine__create_kernel_maps
      perf machine: Remove machine__load_kallsyms()
      perf tools: Do not create kernel maps in sample__resolve()
      perf tests: Use arch__compare_symbol_names to compare symbols
      perf report: Fix memory corruption in --branch-history mode --branch-history

Mathieu Poirier (3):
      perf cs-etm: Freeing allocated memory
      perf auxtrace arm: Fixing uninitialised variable
      perf cs-etm: Properly deal with cpu maps

Ravi Bangoria (3):
      tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
      perf powerpc: Generate system call table from asm/unistd.h
      perf trace powerpc: Use generated syscall table

Robert Walker (3):
      perf cs-etm: Inject capabilitity for CoreSight traces
      perf inject: Emit instruction records on ETM trace discontinuity
      coresight: Update documentation for perf usage

Sangwon Hong (2):
      perf kmem: Document a missing option & an argument
      perf mem: Document a missing option

Thomas Richter (5):
      perf record: Provide detailed information on s390 CPU
      perf annotate: Scan cpuid for s390 and save machine type
      perf cpuid: Introduce a platform specific cpuid compare function
      perf test: Fix test case 23 for s390 z/VM or KVM guests
      perf test: Fix test case inet_pton to accept inlines.

yuzhoujian (2):
      perf stat: Add support to print counts for fixed times
      perf stat: Add support to print counts after a period of time

 Documentation/trace/coresight.txt                  |  51 +++
 tools/arch/powerpc/include/uapi/asm/unistd.h       | 402 +++++++++++++++++
 tools/lib/api/fs/fs.c                              |  44 +-
 tools/lib/api/fs/fs.h                              |   2 +
 tools/lib/symbol/kallsyms.c                        |   4 +
 tools/perf/Documentation/perf-annotate.txt         |   6 +-
 tools/perf/Documentation/perf-kmem.txt             |   6 +-
 tools/perf/Documentation/perf-mem.txt              |   4 +
 tools/perf/Documentation/perf-report.txt           |   5 +-
 tools/perf/Documentation/perf-script.txt           |   3 +
 tools/perf/Documentation/perf-stat.txt             |  10 +
 tools/perf/Makefile.config                         |   2 +
 tools/perf/arch/arm/util/auxtrace.c                |   2 +-
 tools/perf/arch/arm/util/cs-etm.c                  |  51 ++-
 tools/perf/arch/powerpc/Makefile                   |  25 ++
 .../perf/arch/powerpc/entry/syscalls/mksyscalltbl  |  37 ++
 tools/perf/arch/s390/annotate/instructions.c       |  27 +-
 tools/perf/arch/s390/util/header.c                 | 148 ++++++-
 tools/perf/builtin-record.c                        |   2 +-
 tools/perf/builtin-report.c                        |   7 +-
 tools/perf/builtin-script.c                        |  17 +
 tools/perf/builtin-stat.c                          |  53 ++-
 tools/perf/check-headers.sh                        |   1 +
 tools/perf/tests/code-reading.c                    |  33 +-
 tools/perf/tests/dwarf-unwind.c                    |  46 +-
 tools/perf/tests/shell/lib/probe_vfs_getname.sh    |   2 +-
 .../perf/tests/shell/trace+probe_libc_inet_pton.sh |   6 +-
 tools/perf/tests/vmlinux-kallsyms.c                |   4 +-
 tools/perf/ui/browsers/annotate.c                  |   9 +-
 tools/perf/util/build-id.c                         |  10 +-
 tools/perf/util/cs-etm-decoder/cs-etm-decoder.c    |  74 +++-
 tools/perf/util/cs-etm-decoder/cs-etm-decoder.h    |   2 +
 tools/perf/util/cs-etm.c                           | 478 ++++++++++++++++++---
 tools/perf/util/event.c                            |  16 +-
 tools/perf/util/evlist.c                           |  21 +-
 tools/perf/util/header.h                           |   1 +
 tools/perf/util/hist.c                             |   4 +-
 tools/perf/util/hist.h                             |   1 -
 tools/perf/util/machine.c                          | 145 +++----
 tools/perf/util/machine.h                          |   6 +-
 tools/perf/util/pmu.c                              |  47 +-
 tools/perf/util/sort.c                             |   7 +-
 tools/perf/util/stat.h                             |   2 +
 tools/perf/util/symbol.c                           |  13 +-
 tools/perf/util/syscalltbl.c                       |   8 +
 tools/perf/util/thread_map.c                       |   4 +-
 tools/perf/util/thread_map.h                       |   2 +-
 47 files changed, 1577 insertions(+), 273 deletions(-)
 create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h
 create mode 100755 tools/perf/arch/powerpc/entry/syscalls/mksyscalltbl

Test results:

The first ones are container (docker) based builds of tools/perf with and
without libelf support.  Where clang is available, it is also used to build
perf with/without libelf.

The objtool and samples/bpf/ builds are disabled now that I'm switching from
using the sources in a local volume to fetching them from a http server to
build it inside the container, to make it easier to build in a container cluster.
Those will come back later.

Several are cross builds, the ones with -x-ARCH and the android one, and those
may not have all the features built, due to lack of multi-arch devel packages,
available and being used so far on just a few, like
debian:experimental-x-{arm64,mipsel}.

The 'perf test' one will perform a variety of tests exercising
tools/perf/util/, tools/lib/{bpf,traceevent,etc}, as well as run perf commands
with a variety of command line event specifications to then intercept the
sys_perf_event syscall to check that the perf_event_attr fields are set up as
expected, among a variety of other unit tests.

Then there is the 'make -C tools/perf build-test' ones, that build tools/perf/
with a variety of feature sets, exercising the build with an incomplete set of
features as well as with a complete one. It is planned to have it run on each
of the containers mentioned above, using some container orchestration
infrastructure. Get in contact if interested in helping having this in place.

  On a Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz

  # dm
   1 39.82 alpine:3.4                    : Ok   gcc (Alpine 5.3.0) 5.3.0
   2 57.59 alpine:3.5                    : Ok   gcc (Alpine 6.2.1) 6.2.1 20160822
   3 44.30 alpine:3.6                    : Ok   gcc (Alpine 6.3.0) 6.3.0
   4 42.14 alpine:edge                   : Ok   gcc (Alpine 6.4.0) 6.4.0
   5 35.50 amazonlinux:1                 : Ok   gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-11)
   6 42.97 amazonlinux:2                 : Ok   gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2)
   7 26.46 android-ndk:r12b-arm          : Ok   arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
   8 27.28 android-ndk:r15c-arm          : Ok   arm-linux-androideabi-gcc (GCC) 4.9.x 20150123 (prerelease)
   9 24.29 centos:5                      : Ok   gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-55)
  10 32.15 centos:6                      : Ok   gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
  11 39.36 centos:7                      : Ok   gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16)
  12 34.69 debian:7                      : Ok   gcc (Debian 4.7.2-5) 4.7.2
  13 37.92 debian:8                      : Ok   gcc (Debian 4.9.2-10) 4.9.2
  14 62.13 debian:9                      : Ok   gcc (Debian 6.3.0-18) 6.3.0 20170516
  15 65.51 debian:experimental           : Ok   gcc (Debian 7.2.0-18) 7.2.0
  16 38.73 debian:experimental-x-arm64   : Ok   aarch64-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
  17 68.18 debian:experimental-x-mips    : Ok   mips-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
  18 36.21 debian:experimental-x-mips64  : Ok   mips64-linux-gnuabi64-gcc (Debian 7.2.0-11) 7.2.0
  19 37.57 debian:experimental-x-mipsel  : Ok   mipsel-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
  20 38.22 fedora:20                     : Ok   gcc (GCC) 4.8.3 20140911 (Red Hat 4.8.3-7)
  21 42.49 fedora:21                     : Ok   gcc (GCC) 4.9.2 20150212 (Red Hat 4.9.2-6)
  22 39.15 fedora:22                     : Ok   gcc (GCC) 5.3.1 20160406 (Red Hat 5.3.1-6)
  23 41.46 fedora:23                     : Ok   gcc (GCC) 5.3.1 20160406 (Red Hat 5.3.1-6)
  24 41.12 fedora:24                     : Ok   gcc (GCC) 6.3.1 20161221 (Red Hat 6.3.1-1)
  25 34.92 fedora:24-x-ARC-uClibc        : Ok   arc-linux-gcc (ARCompact ISA Linux uClibc toolchain 2017.09-rc2) 7.1.1 20170710
  26 78.28 fedora:25                     : Ok   gcc (GCC) 6.4.1 20170727 (Red Hat 6.4.1-1)
  27 84.02 fedora:26                     : Ok   gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2)
  28 95.42 fedora:27                     : Ok   gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-2)
  29 78.89 fedora:rawhide                : Ok   gcc (GCC) 7.2.1 20170915 (Red Hat 7.2.1-4)
  30 57.48 gentoo-stage3-amd64:latest    : Ok   gcc (Gentoo 6.4.0-r1 p1.3) 6.4.0
  31 41.18 mageia:5                      : Ok   gcc (GCC) 4.9.2
  32 42.27 mageia:6                      : Ok   gcc (Mageia 5.4.0-5.mga6) 5.4.0
  33 39.66 opensuse:42.1                 : Ok   gcc (SUSE Linux) 4.8.5
  34 40.09 opensuse:42.2                 : Ok   gcc (SUSE Linux) 4.8.5
  35 41.01 opensuse:42.3                 : Ok   gcc (SUSE Linux) 4.8.5
  36 82.32 opensuse:tumbleweed           : Ok   gcc (SUSE Linux) 7.3.0
  37 31.70 oraclelinux:6                 : Ok   gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-18)
  38 38.39 oraclelinux:7                 : Ok   gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-16)
  39 30.49 ubuntu:12.04.5                : Ok   gcc (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3
  40 36.44 ubuntu:14.04.4                : Ok   gcc (Ubuntu 4.8.4-2ubuntu1~14.04.3) 4.8.4
  41 32.13 ubuntu:14.04.4-x-linaro-arm64 : Ok   aarch64-linux-gnu-gcc (Linaro GCC 5.5-2017.10) 5.5.0
  42 58.58 ubuntu:16.04                  : Ok   gcc (Ubuntu 5.4.0-6ubuntu1~16.04.6) 5.4.0 20160609
  43 31.52 ubuntu:16.04-x-arm            : Ok   arm-linux-gnueabihf-gcc (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  44 31.06 ubuntu:16.04-x-arm64          : Ok   aarch64-linux-gnu-gcc (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  45 31.61 ubuntu:16.04-x-powerpc        : Ok   powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  46 31.93 ubuntu:16.04-x-powerpc64      : Ok   powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
  47 33.02 ubuntu:16.04-x-powerpc64el    : Ok   powerpc64le-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  48 30.94 ubuntu:16.04-x-s390           : Ok   s390x-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  49 63.24 ubuntu:16.10                  : Ok   gcc (Ubuntu 6.2.0-5ubuntu12) 6.2.0 20161005
  50 63.34 ubuntu:17.04                  : Ok   gcc (Ubuntu 6.3.0-12ubuntu2) 6.3.0 20170406
  51 63.56 ubuntu:17.10                  : Ok   gcc (Ubuntu 7.2.0-8ubuntu3) 7.2.0
  52 63.45 ubuntu:18.04                  : Ok   gcc (Ubuntu 7.2.0-18ubuntu2) 7.2.0

  # uname -a
  Linux jouet 4.15.0-rc9+ #7 SMP Mon Jan 22 18:16:36 -03 2018 x86_64 x86_64 x86_64 GNU/Linux
  # perf test
   1: vmlinux symtab matches kallsyms                       : Ok
   2: Detect openat syscall event                           : Ok
   3: Detect openat syscall event on all cpus               : Ok
   4: Read samples using the mmap interface                 : Ok
   5: Test data source output                               : Ok
   6: Parse event definition strings                        : Ok
   7: Simple expression parser                              : Ok
   8: PERF_RECORD_* events & perf_sample fields             : Ok
   9: Parse perf pmu format                                 : Ok
  10: DSO data read                                         : Ok
  11: DSO data cache                                        : Ok
  12: DSO data reopen                                       : Ok
  13: Roundtrip evsel->name                                 : Ok
  14: Parse sched tracepoints fields                        : Ok
  15: syscalls:sys_enter_openat event fields                : Ok
  16: Setup struct perf_event_attr                          : Ok
  17: Match and link multiple hists                         : Ok
  18: 'import perf' in python                               : Ok
  19: Breakpoint overflow signal handler                    : Ok
  20: Breakpoint overflow sampling                          : Ok
  21: Number of exit events of a simple workload            : Ok
  22: Software clock events period values                   : Ok
  23: Object code reading                                   : Ok
  24: Sample parsing                                        : Ok
  25: Use a dummy software event to keep tracking           : Ok
  26: Parse with no sample_id_all bit set                   : Ok
  27: Filter hist entries                                   : Ok
  28: Lookup mmap thread                                    : Ok
  29: Share thread mg                                       : Ok
  30: Sort output of hist entries                           : Ok
  31: Cumulate child hist entries                           : Ok
  32: Track with sched_switch                               : Ok
  33: Filter fds with revents mask in a fdarray             : Ok
  34: Add fd to a fdarray, making it autogrow               : Ok
  35: kmod_path__parse                                      : Ok
  36: Thread map                                            : Ok
  37: LLVM search and compile                               :
  37.1: Basic BPF llvm compile                              : Ok
  37.2: kbuild searching                                    : Ok
  37.3: Compile source for BPF prologue generation          : Ok
  37.4: Compile source for BPF relocation                   : Ok
  38: Session topology                                      : Ok
  39: BPF filter                                            :
  39.1: Basic BPF filtering                                 : Ok
  39.2: BPF pinning                                         : Ok
  39.3: BPF prologue generation                             : Ok
  39.4: BPF relocation checker                              : Ok
  40: Synthesize thread map                                 : Ok
  41: Remove thread map                                     : Ok
  42: Synthesize cpu map                                    : Ok
  43: Synthesize stat config                                : Ok
  44: Synthesize stat                                       : Ok
  45: Synthesize stat round                                 : Ok
  46: Synthesize attr update                                : Ok
  47: Event times                                           : Ok
  48: Read backward ring buffer                             : Ok
  49: Print cpu map                                         : Ok
  50: Probe SDT events                                      : Ok
  51: is_printable_array                                    : Ok
  52: Print bitmap                                          : Ok
  53: perf hooks                                            : Ok
  54: builtin clang support                                 : Skip (not compiled in)
  55: unit_number__scnprintf                                : Ok
  56: x86 rdpmc                                             : Ok
  57: Convert perf time to TSC                              : Ok
  58: DWARF unwind                                          : Ok
  59: x86 instruction decoder - new instructions            : Ok
  60: Use vfs_getname probe to get syscall args filenames   : Ok
  61: probe libc's inet_pton & backtrace it with ping       : Ok
  62: Check open filename arg using perf trace + vfs_getname: Ok
  63: Add vfs_getname probe to get syscall args filenames   : Ok
  # 
  
  $ make -C tools/perf build-test
  make: Entering directory '/home/acme/git/perf/tools/perf'
  - tarpkg: ./tests/perf-targz-src-pkg .
           make_no_libunwind_O: make NO_LIBUNWIND=1
           make_no_backtrace_O: make NO_BACKTRACE=1
        make_with_babeltrace_O: make LIBBABELTRACE=1
  make_no_libdw_dwarf_unwind_O: make NO_LIBDW_DWARF_UNWIND=1
   make_install_prefix_slash_O: make install prefix=/tmp/krava/
                 make_static_O: make LDFLAGS=-static
                make_minimal_O: make NO_LIBPERL=1 NO_LIBPYTHON=1 NO_NEWT=1 NO_GTK2=1 NO_DEMANGLE=1 NO_LIBELF=1 NO_LIBUNWIND=1 NO_BACKTRACE=1 NO_LIBNUMA=1 NO_LIBAUDIT=1 NO_LIBBIONIC=1 NO_LIBDW_DWARF_UNWIND=1 NO_AUXTRACE=1 NO_LIBBPF=1 NO_LIBCRYPTO=1 NO_SDT=1 NO_JVMTI=1
         make_with_clangllvm_O: make LIBCLANGLLVM=1
                make_install_O: make install
                    make_doc_O: make doc
                   make_pure_O: make
            make_no_libaudit_O: make NO_LIBAUDIT=1
               make_no_slang_O: make NO_SLANG=1
                make_no_gtk2_O: make NO_GTK2=1
            make_install_bin_O: make install-bin
             make_no_libperl_O: make NO_LIBPERL=1
            make_no_demangle_O: make NO_DEMANGLE=1
                   make_tags_O: make tags
            make_no_auxtrace_O: make NO_AUXTRACE=1
       make_util_pmu_bison_o_O: make util/pmu-bison.o
         make_install_prefix_O: make install prefix=/tmp/krava
                  make_debug_O: make DEBUG=1
             make_no_scripts_O: make NO_LIBPYTHON=1 NO_LIBPERL=1
                make_no_newt_O: make NO_NEWT=1
                  make_no_ui_O: make NO_NEWT=1 NO_SLANG=1 NO_GTK2=1
  ^[[5~           make_no_libnuma_O: make NO_LIBNUMA=1
              make_no_libelf_O: make NO_LIBELF=1
                   make_help_O: make help
              make_no_libbpf_O: make NO_LIBBPF=1
           make_no_libpython_O: make NO_LIBPYTHON=1
           make_no_libbionic_O: make NO_LIBBIONIC=1
              make_clean_all_O: make clean all
                 make_perf_o_O: make perf.o
             make_util_map_o_O: make util/map.o
  OK
  make: Leaving directory '/home/acme/git/perf/tools/perf'
  $ 

^ permalink raw reply

* [PATCH 00/23] kconfig: move compiler capability tests to Kconfig
From: Masahiro Yamada @ 2018-02-16 18:38 UTC (permalink / raw)
  To: linux-kbuild, Linus Torvalds
  Cc: Greg Kroah-Hartman, Arnd Bergmann, Kees Cook, Randy Dunlap,
	Ulf Magnusson, Sam Ravnborg, Michal Marek, Masahiro Yamada,
	Peter Oberparleiter, kernel-hardening, Jonathan Corbet,
	sparclinux, linux-sh, x86, Thomas Gleixner, Rich Felker,
	Jeff Dike, H. Peter Anvin, user-mode-linux-devel, Yoshinori Sato,
	Benjamin Herrenschmidt, linuxppc-dev, Paul Mackerras,
	user-mode-linux-user, Ingo Molnar, David S. Miller,
	Michael Ellerman, linux-doc, linux-kernel, Richard Weinberger,
	Emese Revfy

I brushed up the implementation in this version.

In the previous RFC, CC_HAS_ was described by using 'option shell=',
like this:

config CC_HAS_STACKPROTECTOR
        bool
        option shell="$CC -Werror -fstack-protector -c -x c /dev/null"

After I thought a bit more, the following syntax is more grammatical,
and flexible.

config CC_HAS_STACKPROTECTOR
        bool
        default $(shell $CC -Werror -fstack-protector -c -x c /dev/null)

This version supports cc-option, so it can be written as:

config CC_HAS_STACKPROTECTOR
        bool
        default $(cc-option -fstack-protector)

To support this in a clean way, I introduced a new concept 'function'
like we see in Makefiles.

$(shell ...) is a built-in function.  $(cc-option ...) is implemented
as macro (user-defined function).

I also try cleaning of stack-protector, gcc-plugins since the Makefile
is so dirty.

Current limitations:

Dependency on outside scripts.
  For example, scripts/gcc-x86_64-has-stack-protecter.sh is run from
  Kconfig.  When the shell script is updated, should Kconfig be re-run
  automatically?

Inter-option dependency:
  $(call cc-option,...) in Makefile accumulates added options to
  KBUILD_CFLAGS, but it is difficult to do it in Kconfig.
  If a compiler option check is dependent on another option,
  this is a difficult case.  Let's see how significant it is.

Functions are evaluated statically:
  Functions are only expanded when parsing the Kconfig.  So, it can
  not refelect user configuration.  If this is required, $(shell )
  must be dynamically re-calculated depending on other symbols.
  But, this is difficult, and may cause performance issue.



Masahiro Yamada (22):
  kbuild: remove kbuild cache
  kbuild: remove CONFIG_CROSS_COMPILE support
  kconfig: add xstrdup() helper
  kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
  kconfig: move and rename sym_expand_string_value()
  kconfig: reference environments directly and remove 'option env='
    syntax
  kconfig: add function support and implement 'shell' function
  kconfig: add 'macro' keyword to support user-defined function
  kconfig: add 'cc-option' macro
  stack-protector: test compiler capability in Kconfig and drop AUTO
    mode
  kconfig: add 'shell-stdout' function
  kconfig: replace $UNAME_RELEASE with function call
  kconfig: expand environments/functions in (main)menu, comment, prompt
  kconfig: show compiler version text in the top comment
  kconfig: add CC_IS_GCC and GCC_VERSION
  kconfig: add CC_IS_CLANG and CLANG_VERSION
  gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT
  kcov: imply GCC_PLUGINS and GCC_PLUGIN_SANCOV instead of select'ing
    them
  gcc-plugins: always build plugins with C++
  gcc-plugins: move GCC version check for PowerPC to Kconfig
  gcc-plugins: test GCC plugin support in Kconfig
  gcc-plugins: enable GCC_PLUGINS for COMPILE_TEST

Sami Tolvanen (1):
  kbuild: add clang-version.sh

 Documentation/kbuild/kconfig-language.txt |   8 -
 Kconfig                                   |   4 +-
 Makefile                                  | 103 ++----------
 arch/Kconfig                              |  43 +++--
 arch/powerpc/Kconfig                      |   2 +-
 arch/sh/Kconfig                           |   4 +-
 arch/sparc/Kconfig                        |   4 +-
 arch/tile/Kconfig                         |   2 +-
 arch/um/Kconfig.common                    |   4 -
 arch/x86/Kconfig                          |  12 +-
 arch/x86/um/Kconfig                       |   4 +-
 init/Kconfig                              |  44 +++---
 kernel/gcov/Kconfig                       |  18 +--
 kernel/gcov/Makefile                      |   2 -
 lib/Kconfig.debug                         |   7 +-
 scripts/Kbuild.include                    | 101 ++----------
 scripts/Makefile.gcc-plugins              |  95 ++++-------
 scripts/clang-version.sh                  |  31 ++++
 scripts/gcc-plugin.sh                     |  37 +----
 scripts/gcc-plugins/Makefile              |  15 +-
 scripts/gcc-x86_32-has-stack-protector.sh |   7 +-
 scripts/gcc-x86_64-has-stack-protector.sh |   5 -
 scripts/kconfig/confdata.c                |  33 +---
 scripts/kconfig/function.c                | 251 ++++++++++++++++++++++++++++++
 scripts/kconfig/kconf_id.c                |   2 +-
 scripts/kconfig/kxgettext.c               |   2 +-
 scripts/kconfig/lkc.h                     |   6 +-
 scripts/kconfig/lkc_proto.h               |   7 +-
 scripts/kconfig/menu.c                    |   6 +-
 scripts/kconfig/symbol.c                  | 139 +++--------------
 scripts/kconfig/util.c                    | 186 ++++++++++++++++++++--
 scripts/kconfig/zconf.l                   |  40 ++++-
 scripts/kconfig/zconf.y                   |  48 +++---
 33 files changed, 687 insertions(+), 585 deletions(-)
 create mode 100755 scripts/clang-version.sh
 create mode 100644 scripts/kconfig/function.c

-- 
2.7.4

^ permalink raw reply

* [PATCH 21/23] gcc-plugins: move GCC version check for PowerPC to Kconfig
From: Masahiro Yamada @ 2018-02-16 18:38 UTC (permalink / raw)
  To: linux-kbuild, Linus Torvalds
  Cc: Greg Kroah-Hartman, Arnd Bergmann, Kees Cook, Randy Dunlap,
	Ulf Magnusson, Sam Ravnborg, Michal Marek, Masahiro Yamada,
	Michael Ellerman, Benjamin Herrenschmidt, linux-kernel,
	Paul Mackerras, kernel-hardening, linuxppc-dev, Emese Revfy
In-Reply-To: <1518806331-7101-1-git-send-email-yamada.masahiro@socionext.com>

For PowerPC, GCC 5.2 is the requirement for GCC plugins.  Move the
version check to Kconfig, and remove the ugly checker.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 arch/powerpc/Kconfig         | 2 +-
 scripts/Makefile.gcc-plugins | 8 --------
 2 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 73ce5dd..b8474c2 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -195,7 +195,7 @@ config PPC
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
-	select HAVE_GCC_PLUGINS
+	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 50200
 	select HAVE_GENERIC_GUP
 	select HAVE_HW_BREAKPOINT		if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
 	select HAVE_IDE
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
index b0f9108..25da4c0 100644
--- a/scripts/Makefile.gcc-plugins
+++ b/scripts/Makefile.gcc-plugins
@@ -56,14 +56,6 @@ gcc-plugins-check: FORCE
 ifdef CONFIG_GCC_PLUGINS
   ifeq ($(PLUGINCC),)
     ifneq ($(GCC_PLUGINS_CFLAGS),)
-      # Various gccs between 4.5 and 5.1 have bugs on powerpc due to missing
-      # header files. gcc <= 4.6 doesn't work at all, gccs from 4.8 to 5.1 have
-      # issues with 64-bit targets.
-      ifeq ($(ARCH),powerpc)
-        ifeq ($(call cc-ifversion, -le, 0501, y), y)
-	  @echo "Cannot use CONFIG_GCC_PLUGINS: plugin support on gcc <= 5.1 is buggy on powerpc, please upgrade to gcc 5.2 or newer" >&2 && exit 1
-        endif
-      endif
       $(Q)$(srctree)/scripts/gcc-plugin.sh --show-error $(HOSTCXX) $(CC) || true
       @echo "Cannot use CONFIG_GCC_PLUGINS: your gcc installation does not support plugins, perhaps the necessary headers are missing?" >&2 && exit 1
     endif
-- 
2.7.4

^ permalink raw reply related

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 17:50 UTC (permalink / raw)
  To: Ravi Bangoria
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe
In-Reply-To: <20180216172901.GB16919@kernel.org>

Em Fri, Feb 16, 2018 at 02:29:01PM -0300, Arnaldo Carvalho de Melo escreveu:
> Humm, we need to create two tables, one for 32-bit and another for 64,
> even with ppc not having (AFAIK) clashes in syscall numbers for 32/64...
> 
> Trying to do it now.

Now seems to work, take a look at my perf/core branch, should be one of the first few csets.

perfbuilder@cc1a85517216:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_32.c 
	[192] = "mmap2",
perfbuilder@cc1a85517216:/git/perf$ powerpc-linux-gnu-gcc --version
powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
perfbuilder@cc1a85517216:/git/perf$

perfbuilder@9d7fc9dcfb73:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_32.c
	[192] = "mmap2",
perfbuilder@9d7fc9dcfb73:/git/perf$ grep 192 /tmp/build/perf/arch/powerpc/include/generated/asm/syscalls_64.c
perfbuilder@9d7fc9dcfb73:/git/perf$ powerpc64-linux-gnu-gcc --version
powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
perfbuilder@9d7fc9dcfb73:/git/perf$ 

^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 17:29 UTC (permalink / raw)
  To: Ravi Bangoria
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe
In-Reply-To: <20180216170812.GA16919@kernel.org>

Em Fri, Feb 16, 2018 at 02:08:12PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Fri, Feb 16, 2018 at 02:03:36PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Fri, Feb 16, 2018 at 01:56:16PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > Em Fri, Feb 16, 2018 at 01:52:45PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > > Em Mon, Jan 29, 2018 at 02:04:15PM +0530, Ravi Bangoria escreveu:
> > > > > Will be used for generating the syscall id/string translation table.
> > > > > 
> > > > > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> > > > > ---
> > > > >  tools/arch/powerpc/include/uapi/asm/unistd.h | 399 +++++++++++++++++++++++++++
> > > > >  tools/perf/check-headers.sh                  |   1 +
> > > > >  2 files changed, 400 insertions(+)
> > > > >  create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h
> > > > 
> > > > Not building on a cross-compiling environment (ubuntu 16.04), I'm checking...
> > > 
> > > BTW, details about that environment:
> > > 
> > >   46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> > 
> > So, you did it just for ppc64? Because...
> > 
> >   46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> >   47    69.81 ubuntu:16.04-x-powerpc64      : Ok   powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
> >   48    68.35 ubuntu:16.04-x-powerpc64el    : Ok   powerpc64le-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> > 
> > Its just on ppc32 that his is falling apart.
> 
> So, $(SRCARCH) maps to both powerpc and powerpc64m which will set
> NO_SYSCALL_TABLE to zero, thus linking against
> tools/perf/util/syscalltbl.o, which will include the generated
> syscalls_64.c only for ppc64, b00m.

Ok, so after looking at:

commit eef289f79c03ba5ca197e2ac1e33906175f01c39
Author: Paul Mackerras <paulus@samba.org>
Date:   Mon Oct 10 22:56:11 2005 +1000

    powerpc: Merge asm/unistd.h
    
    Signed-off-by: Paul Mackerras <paulus@samba.org>

----

Humm, we need to create two tables, one for 32-bit and another for 64,
even with ppc not having (AFAIK) clashes in syscall numbers for 32/64...

Trying to do it now.

- Arnaldo

^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 17:08 UTC (permalink / raw)
  To: Ravi Bangoria
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe
In-Reply-To: <20180216170336.GG24436@kernel.org>

Em Fri, Feb 16, 2018 at 02:03:36PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Fri, Feb 16, 2018 at 01:56:16PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Fri, Feb 16, 2018 at 01:52:45PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > Em Mon, Jan 29, 2018 at 02:04:15PM +0530, Ravi Bangoria escreveu:
> > > > Will be used for generating the syscall id/string translation table.
> > > > 
> > > > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> > > > ---
> > > >  tools/arch/powerpc/include/uapi/asm/unistd.h | 399 +++++++++++++++++++++++++++
> > > >  tools/perf/check-headers.sh                  |   1 +
> > > >  2 files changed, 400 insertions(+)
> > > >  create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h
> > > 
> > > Not building on a cross-compiling environment (ubuntu 16.04), I'm checking...
> > 
> > BTW, details about that environment:
> > 
> >   46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> 
> So, you did it just for ppc64? Because...
> 
>   46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
>   47    69.81 ubuntu:16.04-x-powerpc64      : Ok   powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
>   48    68.35 ubuntu:16.04-x-powerpc64el    : Ok   powerpc64le-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
> 
> Its just on ppc32 that his is falling apart.

So, $(SRCARCH) maps to both powerpc and powerpc64m which will set
NO_SYSCALL_TABLE to zero, thus linking against
tools/perf/util/syscalltbl.o, which will include the generated
syscalls_64.c only for ppc64, b00m.

+++ b/tools/perf/Makefile.config
@@ -27,6 +27,8 @@ NO_SYSCALL_TABLE := 1
 # Additional ARCH settings for ppc
 ifeq ($(SRCARCH),powerpc)
   NO_PERF_REGS := 0
+  NO_SYSCALL_TABLE := 0
+  CFLAGS += -I$(OUTPUT)arch/powerpc/include/generated
   LIBUNWIND_LIBS := -lunwind -lunwind-ppc64
 endif
 
+++ b/tools/perf/util/syscalltbl.c
 static const char **syscalltbl_native = syscalltbl_s390_64;
+#elif defined(__powerpc64__)
+#include <asm/syscalls_64.c>
+const int syscalltbl_native_max_id = SYSCALLTBL_POWERPC_64_MAX_ID;
+static const char **syscalltbl_native = syscalltbl_powerpc_64;
 #endif

^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 17:03 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: Ravi Bangoria, alexander.shishkin, jolsa, namhyung, linux-kernel,
	brueckner, tmricht, linuxppc-dev, mpe
In-Reply-To: <20180216165616.GF24436@kernel.org>

Em Fri, Feb 16, 2018 at 01:56:16PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Fri, Feb 16, 2018 at 01:52:45PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Mon, Jan 29, 2018 at 02:04:15PM +0530, Ravi Bangoria escreveu:
> > > Will be used for generating the syscall id/string translation table.
> > > 
> > > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> > > ---
> > >  tools/arch/powerpc/include/uapi/asm/unistd.h | 399 +++++++++++++++++++++++++++
> > >  tools/perf/check-headers.sh                  |   1 +
> > >  2 files changed, 400 insertions(+)
> > >  create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h
> > 
> > Not building on a cross-compiling environment (ubuntu 16.04), I'm checking...
> 
> BTW, details about that environment:
> 
>   46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

So, you did it just for ppc64? Because...

  46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
  47    69.81 ubuntu:16.04-x-powerpc64      : Ok   powerpc64-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.1) 5.4.0 20160609
  48    68.35 ubuntu:16.04-x-powerpc64el    : Ok   powerpc64le-linux-gnu-gcc (Ubuntu/IBM 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

Its just on ppc32 that his is falling apart.
 
>  
> >   CC       /tmp/build/perf/util/syscalltbl.o
> > util/syscalltbl.c: In function 'syscalltbl__init_native':
> > util/syscalltbl.c:64:19: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
> >   for (i = 0; i <= syscalltbl_native_max_id; ++i)
> >                    ^
> > util/syscalltbl.c:64:19: note: each undeclared identifier is reported only once for each function it appears in
> > util/syscalltbl.c:65:7: error: 'syscalltbl_native' undeclared (first use in this function)
> >    if (syscalltbl_native[i])
> >        ^
> > util/syscalltbl.c: In function 'syscalltbl__name':
> > util/syscalltbl.c:105:15: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
> >   return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
> >                ^
> > util/syscalltbl.c:105:42: error: 'syscalltbl_native' undeclared (first use in this function)
> >   return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
> >                                           ^
> > util/syscalltbl.c:106:1: error: control reaches end of non-void function [-Werror=return-type]
> >  }
> >  ^
> > cc1: all warnings being treated as errors
> > mv: cannot stat '/tmp/build/perf/util/.syscalltbl.o.tmp': No such file or directory
> > /git/linux/tools/build/Makefile.build:96: recipe for target '/tmp/build/perf/util/syscalltbl.o' failed
> > make[4]: *** [/tmp/build/perf/util/syscalltbl.o] Error 1
> > make[4]: *** Waiting for unfinished jobs....
> >   CC       /tmp/build/perf/tests/sample-parsing.o
> >   CC       /tmp/build/perf/tests/parse-no-sample-id-all.o
> >   CC       /tmp/build/perf/tests/kmod-path.o
> >   CC       /tmp/build/perf/tests/thread-map.o
> >   CC       /tmp/build/perf/tests/llvm.o
> >   CC       /tmp/build/perf/tests/bpf.o
> >   CC       /tmp/build/perf/tests/topology.o
> >   CC       /tmp/build/perf/tests/mem.o
> >   CC       /tmp/build/perf/tests/cpumap.o
> >   CC       /tmp/build/perf/tests/stat.o
> > /git/linux/tools/build/Makefile.build:139: recipe for target 'util' failed
> > make[3]: *** [util] Error 2
> > Makefile.perf:629: recipe for target '/tmp/build/perf/libperf-in.o' failed
> > make[2]: *** [/tmp/build/perf/libperf-in.o] Error 2
> > make[2]: *** Waiting for unfinished jobs....
> >   CC       /tmp/build/perf/tests/event_update.o

^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 16:56 UTC (permalink / raw)
  To: Ravi Bangoria
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe
In-Reply-To: <20180216165245.GD24436@kernel.org>

Em Fri, Feb 16, 2018 at 01:52:45PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Jan 29, 2018 at 02:04:15PM +0530, Ravi Bangoria escreveu:
> > Will be used for generating the syscall id/string translation table.
> > 
> > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> > ---
> >  tools/arch/powerpc/include/uapi/asm/unistd.h | 399 +++++++++++++++++++++++++++
> >  tools/perf/check-headers.sh                  |   1 +
> >  2 files changed, 400 insertions(+)
> >  create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h
> 
> Not building on a cross-compiling environment (ubuntu 16.04), I'm checking...

BTW, details about that environment:

  46    29.83 ubuntu:16.04-x-powerpc        : FAIL powerpc-linux-gnu-gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

 
>   CC       /tmp/build/perf/util/syscalltbl.o
> util/syscalltbl.c: In function 'syscalltbl__init_native':
> util/syscalltbl.c:64:19: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
>   for (i = 0; i <= syscalltbl_native_max_id; ++i)
>                    ^
> util/syscalltbl.c:64:19: note: each undeclared identifier is reported only once for each function it appears in
> util/syscalltbl.c:65:7: error: 'syscalltbl_native' undeclared (first use in this function)
>    if (syscalltbl_native[i])
>        ^
> util/syscalltbl.c: In function 'syscalltbl__name':
> util/syscalltbl.c:105:15: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
>   return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
>                ^
> util/syscalltbl.c:105:42: error: 'syscalltbl_native' undeclared (first use in this function)
>   return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
>                                           ^
> util/syscalltbl.c:106:1: error: control reaches end of non-void function [-Werror=return-type]
>  }
>  ^
> cc1: all warnings being treated as errors
> mv: cannot stat '/tmp/build/perf/util/.syscalltbl.o.tmp': No such file or directory
> /git/linux/tools/build/Makefile.build:96: recipe for target '/tmp/build/perf/util/syscalltbl.o' failed
> make[4]: *** [/tmp/build/perf/util/syscalltbl.o] Error 1
> make[4]: *** Waiting for unfinished jobs....
>   CC       /tmp/build/perf/tests/sample-parsing.o
>   CC       /tmp/build/perf/tests/parse-no-sample-id-all.o
>   CC       /tmp/build/perf/tests/kmod-path.o
>   CC       /tmp/build/perf/tests/thread-map.o
>   CC       /tmp/build/perf/tests/llvm.o
>   CC       /tmp/build/perf/tests/bpf.o
>   CC       /tmp/build/perf/tests/topology.o
>   CC       /tmp/build/perf/tests/mem.o
>   CC       /tmp/build/perf/tests/cpumap.o
>   CC       /tmp/build/perf/tests/stat.o
> /git/linux/tools/build/Makefile.build:139: recipe for target 'util' failed
> make[3]: *** [util] Error 2
> Makefile.perf:629: recipe for target '/tmp/build/perf/libperf-in.o' failed
> make[2]: *** [/tmp/build/perf/libperf-in.o] Error 2
> make[2]: *** Waiting for unfinished jobs....
>   CC       /tmp/build/perf/tests/event_update.o

^ permalink raw reply

* Re: [PATCH 1/3] tools include powerpc: Grab a copy of arch/powerpc/include/uapi/asm/unistd.h
From: Arnaldo Carvalho de Melo @ 2018-02-16 16:52 UTC (permalink / raw)
  To: Ravi Bangoria
  Cc: alexander.shishkin, jolsa, namhyung, linux-kernel, brueckner,
	tmricht, linuxppc-dev, mpe
In-Reply-To: <20180129083417.31240-2-ravi.bangoria@linux.vnet.ibm.com>

Em Mon, Jan 29, 2018 at 02:04:15PM +0530, Ravi Bangoria escreveu:
> Will be used for generating the syscall id/string translation table.
> 
> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
> ---
>  tools/arch/powerpc/include/uapi/asm/unistd.h | 399 +++++++++++++++++++++++++++
>  tools/perf/check-headers.sh                  |   1 +
>  2 files changed, 400 insertions(+)
>  create mode 100644 tools/arch/powerpc/include/uapi/asm/unistd.h

Not building on a cross-compiling environment (ubuntu 16.04), I'm checking...

  CC       /tmp/build/perf/util/syscalltbl.o
util/syscalltbl.c: In function 'syscalltbl__init_native':
util/syscalltbl.c:64:19: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
  for (i = 0; i <= syscalltbl_native_max_id; ++i)
                   ^
util/syscalltbl.c:64:19: note: each undeclared identifier is reported only once for each function it appears in
util/syscalltbl.c:65:7: error: 'syscalltbl_native' undeclared (first use in this function)
   if (syscalltbl_native[i])
       ^
util/syscalltbl.c: In function 'syscalltbl__name':
util/syscalltbl.c:105:15: error: 'syscalltbl_native_max_id' undeclared (first use in this function)
  return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
               ^
util/syscalltbl.c:105:42: error: 'syscalltbl_native' undeclared (first use in this function)
  return id <= syscalltbl_native_max_id ? syscalltbl_native[id]: NULL;
                                          ^
util/syscalltbl.c:106:1: error: control reaches end of non-void function [-Werror=return-type]
 }
 ^
cc1: all warnings being treated as errors
mv: cannot stat '/tmp/build/perf/util/.syscalltbl.o.tmp': No such file or directory
/git/linux/tools/build/Makefile.build:96: recipe for target '/tmp/build/perf/util/syscalltbl.o' failed
make[4]: *** [/tmp/build/perf/util/syscalltbl.o] Error 1
make[4]: *** Waiting for unfinished jobs....
  CC       /tmp/build/perf/tests/sample-parsing.o
  CC       /tmp/build/perf/tests/parse-no-sample-id-all.o
  CC       /tmp/build/perf/tests/kmod-path.o
  CC       /tmp/build/perf/tests/thread-map.o
  CC       /tmp/build/perf/tests/llvm.o
  CC       /tmp/build/perf/tests/bpf.o
  CC       /tmp/build/perf/tests/topology.o
  CC       /tmp/build/perf/tests/mem.o
  CC       /tmp/build/perf/tests/cpumap.o
  CC       /tmp/build/perf/tests/stat.o
/git/linux/tools/build/Makefile.build:139: recipe for target 'util' failed
make[3]: *** [util] Error 2
Makefile.perf:629: recipe for target '/tmp/build/perf/libperf-in.o' failed
make[2]: *** [/tmp/build/perf/libperf-in.o] Error 2
make[2]: *** Waiting for unfinished jobs....
  CC       /tmp/build/perf/tests/event_update.o

^ permalink raw reply

* Re: [RFC][PATCH bpf v2 1/2] bpf: allow 64-bit offsets for bpf function calls
From: Naveen N. Rao @ 2018-02-16 15:50 UTC (permalink / raw)
  To: ast, Daniel Borkmann, Sandipan Das, Michael Ellerman
  Cc: linuxppc-dev, netdev, Michael Holzheu
In-Reply-To: <ad895533-2f15-bfe4-671c-6d1a8c672bbd@iogearbox.net>

Daniel Borkmann wrote:
> On 02/15/2018 05:25 PM, Daniel Borkmann wrote:
>> On 02/13/2018 05:05 AM, Sandipan Das wrote:
>>> The imm field of a bpf_insn is a signed 32-bit integer. For
>>> JIT-ed bpf-to-bpf function calls, it stores the offset from
>>> __bpf_call_base to the start of the callee function.
>>>
>>> For some architectures, such as powerpc64, it was found that
>>> this offset may be as large as 64 bits because of which this
>>> cannot be accomodated in the imm field without truncation.
>>>
>>> To resolve this, we additionally make aux->func within each
>>> bpf_prog associated with the functions to point to the list
>>> of all function addresses determined by the verifier.
>>>
>>> We keep the value assigned to the off field of the bpf_insn
>>> as a way to index into aux->func and also set aux->func_cnt
>>> so that this can be used for performing basic upper bound
>>> checks for the off field.
>>>
>>> Signed-off-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
>>> ---
>>> v2: Make aux->func point to the list of functions determined
>>>     by the verifier rather than allocating a separate callee
>>>     list for each function.
>>=20
>> Approach looks good to me; do you know whether s390x JIT would
>> have similar requirement? I think one limitation that would still
>> need to be addressed later with such approach would be regarding the
>> xlated prog dump in bpftool, see 'BPF calls via JIT' in 7105e828c087
>> ("bpf: allow for correlation of maps and helpers in dump"). Any
>> ideas for this (potentially if we could use off + imm for calls,
>> we'd get to 48 bits, but that seems still not be enough as you say)?

All good points. I'm not really sure how s390x works, so I can't comment=20
on that, but I'm copying Michael Holzheu for his consideration.

With the existing scheme, 48 bits won't be enough, so we rejected that=20
approach. I can also see how this will be a problem with bpftool, but I=20
haven't looked into it in detail. I wonder if we can annotate the output=20
to indicate the function being referred to?

>=20
> One other random thought, although I'm not sure how feasible this
> is for ppc64 JIT to realize ... but idea would be to have something
> like the below:
>=20
> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
> index 29ca920..daa7258 100644
> --- a/kernel/bpf/core.c
> +++ b/kernel/bpf/core.c
> @@ -512,6 +512,11 @@ int bpf_get_kallsym(unsigned int symnum, unsigned lo=
ng *value, char *type,
>  	return ret;
>  }
>=20
> +void * __weak bpf_jit_image_alloc(unsigned long size)
> +{
> +	return module_alloc(size);
> +}
> +
>  struct bpf_binary_header *
>  bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
>  		     unsigned int alignment,
> @@ -525,7 +530,7 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image=
_ptr,
>  	 * random section of illegal instructions.
>  	 */
>  	size =3D round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
> -	hdr =3D module_alloc(size);
> +	hdr =3D bpf_jit_image_alloc(size);
>  	if (hdr =3D=3D NULL)
>  		return NULL;
>=20
> And ppc64 JIT could override bpf_jit_image_alloc() in a similar way
> like some archs would override the module_alloc() helper through a
> custom implementation, usually via __vmalloc_node_range(), so we
> could perhaps fit the range for BPF JITed images in a way that they
> could use the 32bit imm in the end? There are not that many progs
> loaded typically, so the range could be a bit narrower in such case
> anyway. (Not sure if this would work out though, but I thought to
> bring it up.)

That'd be a good option to consider. I don't think we want to allocate=20
anything from the linear memory range since users could load=20
unprivileged BPF programs and consume a lot of memory that way. I doubt=20
if we can map vmalloc'ed memory into the 0xc0 address range, but I'm not=20
entirely sure.

Michael,
Is the above possible? The question is if we can have BPF programs be=20
allocated within 4GB of __bpf_call_base (which is a kernel symbol), so=20
that calls to those programs can be encoded in a 32-bit immediate field=20
in a BPF instruction. As an extension, we may be able to extend it to=20
48-bits by combining with another BPF instruction field (offset). In=20
either case, the vmalloc'ed address range won't work.

The alternative is to pass the full 64-bit address of the BPF program in=20
an auxiliary field (as proposed in this patch set) but we need to fix it=20
up for 'bpftool' as well.

Thanks,
Naveen

=

^ permalink raw reply

* [PATCH V3] cxl: Fix timebase synchronization status on P9
From: Christophe Lombard @ 2018-02-16 15:27 UTC (permalink / raw)
  To: linuxppc-dev, fbarrat, vaibhav, andrew.donnellan

The PSL Timebase register is updated by the PSL to maintain the
timebase.
On P9, the Timebase value is only provided by the CAPP as received
the last time a timebase request was performed.
The timebase requests are initiated through the adapter configuration or
application registers.
The specific sysfs entry "/sys/class/cxl/cardxx/psl_timebase_synced" is
now dynamically updated according the content of the PSL Timebase
register.

Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>

---
This patch applies on top of this patch:
 http://patchwork.ozlabs.org/patch/873663/

Changelog[v3]
 - Rebased to latest upstream.
 - Dynamic update is now applied to P8.

Changelog[v2]
 - Missing Signed-off-by.
 - Spaces required around the ':'.
---
 drivers/misc/cxl/pci.c   | 17 -----------------
 drivers/misc/cxl/sysfs.c | 10 ++++++++++
 2 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 66eed6a..3247eaf 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -606,9 +606,6 @@ static u64 timebase_read_xsl(struct cxl *adapter)
 
 static void cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
 {
-	u64 psl_tb;
-	int delta;
-	unsigned int retry = 0;
 	struct device_node *np;
 
 	adapter->psl_timebase_synced = false;
@@ -636,20 +633,6 @@ static void cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
 	cxl_p1_write(adapter, CXL_PSL_Control, 0x0000000000000000);
 	cxl_p1_write(adapter, CXL_PSL_Control, CXL_PSL_Control_tb);
 
-	/* Wait until CORE TB and PSL TB difference <= 16usecs */
-	do {
-		msleep(1);
-		if (retry++ > 5) {
-			dev_info(&dev->dev, "PSL timebase can't synchronize\n");
-			return;
-		}
-		psl_tb = adapter->native->sl_ops->timebase_read(adapter);
-		delta = mftb() - psl_tb;
-		if (delta < 0)
-			delta = -delta;
-	} while (tb_to_ns(delta) > 16000);
-
-	adapter->psl_timebase_synced = true;
 	return;
 }
 
diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c
index a8b6d6a..3f758d9 100644
--- a/drivers/misc/cxl/sysfs.c
+++ b/drivers/misc/cxl/sysfs.c
@@ -62,6 +62,16 @@ static ssize_t psl_timebase_synced_show(struct device *device,
 					char *buf)
 {
 	struct cxl *adapter = to_cxl_adapter(device);
+	u64 psl_tb;
+	int delta;
+
+	psl_tb = adapter->native->sl_ops->timebase_read(adapter);
+	delta = mftb() - psl_tb;
+	if (delta < 0)
+		delta = -delta;
+
+	/* CORE TB and PSL TB difference <= 16usecs ? */
+	adapter->psl_timebase_synced = (tb_to_ns(delta) < 16000) ? true : false;
 
 	return scnprintf(buf, PAGE_SIZE, "%i\n", adapter->psl_timebase_synced);
 }
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 22/24] mm: Speculative page fault handler return VMA
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

When the speculative page fault handler is returning VM_RETRY, there is a
chance that VMA fetched without grabbing the mmap_sem can be reused by the
legacy page fault handler.  By reusing it, we avoid calling find_vma()
again. To achieve, that we must ensure that the VMA structure will not be
freed in our back. This is done by getting the reference on it (get_vma())
and by assuming that the caller will call the new service
can_reuse_spf_vma() once it has grabbed the mmap_sem.

can_reuse_spf_vma() is first checking that the VMA is still in the RB tree
, and then that the VMA's boundaries matched the passed address and release
the reference on the VMA so that it can be freed if needed.

In the case the VMA is freed, can_reuse_spf_vma() will have returned false
as the VMA is no more in the RB tree.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 include/linux/mm.h |   5 +-
 mm/memory.c        | 136 +++++++++++++++++++++++++++++++++--------------------
 2 files changed, 88 insertions(+), 53 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index c383a4e2ceb3..0cd31a37bb3d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1355,7 +1355,10 @@ extern int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
 		unsigned int flags);
 #ifdef CONFIG_SPECULATIVE_PAGE_FAULT
 extern int handle_speculative_fault(struct mm_struct *mm,
-				    unsigned long address, unsigned int flags);
+				    unsigned long address, unsigned int flags,
+				    struct vm_area_struct **vma);
+extern bool can_reuse_spf_vma(struct vm_area_struct *vma,
+			      unsigned long address);
 #endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
 			    unsigned long address, unsigned int fault_flags,
diff --git a/mm/memory.c b/mm/memory.c
index 2ef686405154..1f5ce5ff79af 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4307,13 +4307,22 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
 /* This is required by vm_normal_page() */
 #error "Speculative page fault handler requires __HAVE_ARCH_PTE_SPECIAL"
 #endif
-
 /*
  * vm_normal_page() adds some processing which should be done while
  * hodling the mmap_sem.
  */
+
+/*
+ * Tries to handle the page fault in a speculative way, without grabbing the
+ * mmap_sem.
+ * When VM_FAULT_RETRY is returned, the vma pointer is valid and this vma must
+ * be checked later when the mmap_sem has been grabbed by calling
+ * can_reuse_spf_vma().
+ * This is needed as the returned vma is kept in memory until the call to
+ * can_reuse_spf_vma() is made.
+ */
 int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
-			     unsigned int flags)
+			     unsigned int flags, struct vm_area_struct **vma)
 {
 	struct vm_fault vmf = {
 		.address = address,
@@ -4322,7 +4331,6 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	p4d_t *p4d, p4dval;
 	pud_t pudval;
 	int seq, ret = VM_FAULT_RETRY;
-	struct vm_area_struct *vma;
 #ifdef CONFIG_NUMA
 	struct mempolicy *pol;
 #endif
@@ -4331,14 +4339,16 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	flags &= ~(FAULT_FLAG_ALLOW_RETRY|FAULT_FLAG_KILLABLE);
 	flags |= FAULT_FLAG_SPECULATIVE;
 
-	vma = get_vma(mm, address);
-	if (!vma)
+	*vma = get_vma(mm, address);
+	if (!*vma)
 		return ret;
+	vmf.vma = *vma;
 
-	seq = raw_read_seqcount(&vma->vm_sequence); /* rmb <-> seqlock,vma_rb_erase() */
+	/* rmb <-> seqlock,vma_rb_erase() */
+	seq = raw_read_seqcount(&vmf.vma->vm_sequence);
 	if (seq & 1) {
-		trace_spf_vma_changed(_RET_IP_, vma, address);
-		goto out_put;
+		trace_spf_vma_changed(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
 	/*
@@ -4346,9 +4356,9 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	 * with the VMA.
 	 * This include huge page from hugetlbfs.
 	 */
-	if (vma->vm_ops) {
-		trace_spf_vma_notsup(_RET_IP_, vma, address);
-		goto out_put;
+	if (vmf.vma->vm_ops) {
+		trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
 	/*
@@ -4356,18 +4366,18 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	 * because vm_next and vm_prev must be safe. This can't be guaranteed
 	 * in the speculative path.
 	 */
-	if (unlikely(!vma->anon_vma)) {
-		trace_spf_vma_notsup(_RET_IP_, vma, address);
-		goto out_put;
+	if (unlikely(!vmf.vma->anon_vma)) {
+		trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
-	vmf.vma_flags = READ_ONCE(vma->vm_flags);
-	vmf.vma_page_prot = READ_ONCE(vma->vm_page_prot);
+	vmf.vma_flags = READ_ONCE(vmf.vma->vm_flags);
+	vmf.vma_page_prot = READ_ONCE(vmf.vma->vm_page_prot);
 
 	/* Can't call userland page fault handler in the speculative path */
 	if (unlikely(vmf.vma_flags & VM_UFFD_MISSING)) {
-		trace_spf_vma_notsup(_RET_IP_, vma, address);
-		goto out_put;
+		trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
 	if (vmf.vma_flags & VM_GROWSDOWN || vmf.vma_flags & VM_GROWSUP) {
@@ -4376,48 +4386,39 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 		 * boundaries but we want to trace it as not supported instead
 		 * of changed.
 		 */
-		trace_spf_vma_notsup(_RET_IP_, vma, address);
-		goto out_put;
+		trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
-	if (address < READ_ONCE(vma->vm_start)
-	    || READ_ONCE(vma->vm_end) <= address) {
-		trace_spf_vma_changed(_RET_IP_, vma, address);
-		goto out_put;
+	if (address < READ_ONCE(vmf.vma->vm_start)
+	    || READ_ONCE(vmf.vma->vm_end) <= address) {
+		trace_spf_vma_changed(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
-	if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+	if (!arch_vma_access_permitted(vmf.vma, flags & FAULT_FLAG_WRITE,
 				       flags & FAULT_FLAG_INSTRUCTION,
-				       flags & FAULT_FLAG_REMOTE)) {
-		trace_spf_vma_access(_RET_IP_, vma, address);
-		ret = VM_FAULT_SIGSEGV;
-		goto out_put;
-	}
+				       flags & FAULT_FLAG_REMOTE))
+		goto out_segv;
 
 	/* This is one is required to check that the VMA has write access set */
 	if (flags & FAULT_FLAG_WRITE) {
-		if (unlikely(!(vmf.vma_flags & VM_WRITE))) {
-			trace_spf_vma_access(_RET_IP_, vma, address);
-			ret = VM_FAULT_SIGSEGV;
-			goto out_put;
-		}
-	} else if (unlikely(!(vmf.vma_flags & (VM_READ|VM_EXEC|VM_WRITE)))) {
-		trace_spf_vma_access(_RET_IP_, vma, address);
-		ret = VM_FAULT_SIGSEGV;
-		goto out_put;
-	}
+		if (unlikely(!(vmf.vma_flags & VM_WRITE)))
+			goto out_segv;
+	} else if (unlikely(!(vmf.vma_flags & (VM_READ|VM_EXEC|VM_WRITE))))
+		goto out_segv;
 
 #ifdef CONFIG_NUMA
 	/*
 	 * MPOL_INTERLEAVE implies additional check in mpol_misplaced() which
 	 * are not compatible with the speculative page fault processing.
 	 */
-	pol = __get_vma_policy(vma, address);
+	pol = __get_vma_policy(vmf.vma, address);
 	if (!pol)
 		pol = get_task_policy(current);
 	if (pol && pol->mode == MPOL_INTERLEAVE) {
-		trace_spf_vma_notsup(_RET_IP_, vma, address);
-		goto out_put;
+		trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 #endif
 
@@ -4479,9 +4480,8 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 		vmf.pte = NULL;
 	}
 
-	vmf.vma = vma;
-	vmf.pgoff = linear_page_index(vma, address);
-	vmf.gfp_mask = __get_fault_gfp_mask(vma);
+	vmf.pgoff = linear_page_index(vmf.vma, address);
+	vmf.gfp_mask = __get_fault_gfp_mask(vmf.vma);
 	vmf.sequence = seq;
 	vmf.flags = flags;
 
@@ -4491,16 +4491,22 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	 * We need to re-validate the VMA after checking the bounds, otherwise
 	 * we might have a false positive on the bounds.
 	 */
-	if (read_seqcount_retry(&vma->vm_sequence, seq)) {
-		trace_spf_vma_changed(_RET_IP_, vma, address);
-		goto out_put;
+	if (read_seqcount_retry(&vmf.vma->vm_sequence, seq)) {
+		trace_spf_vma_changed(_RET_IP_, vmf.vma, address);
+		return ret;
 	}
 
 	mem_cgroup_oom_enable();
 	ret = handle_pte_fault(&vmf);
 	mem_cgroup_oom_disable();
 
-	put_vma(vma);
+	/*
+	 * If there is no need to retry, don't return the vma to the caller.
+	 */
+	if (!(ret & VM_FAULT_RETRY)) {
+		put_vma(vmf.vma);
+		*vma = NULL;
+	}
 
 	/*
 	 * The task may have entered a memcg OOM situation but
@@ -4513,9 +4519,35 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	return ret;
 
 out_walk:
-	trace_spf_vma_notsup(_RET_IP_, vma, address);
+	trace_spf_vma_notsup(_RET_IP_, vmf.vma, address);
 	local_irq_enable();
-out_put:
+	return ret;
+
+out_segv:
+	trace_spf_vma_access(_RET_IP_, vmf.vma, address);
+	/*
+	 * We don't return VM_FAULT_RETRY so the caller is not expected to
+	 * retrieve the fetched VMA.
+	 */
+	put_vma(vmf.vma);
+	*vma = NULL;
+	return VM_FAULT_SIGSEGV;
+}
+
+/*
+ * This is used to know if the vma fetch in the speculative page fault handler
+ * is still valid when trying the regular fault path while holding the
+ * mmap_sem.
+ * The call to put_vma(vma) must be made after checking the vma's fields, as
+ * the vma may be freed by put_vma(). In such a case it is expected that false
+ * is returned.
+ */
+bool can_reuse_spf_vma(struct vm_area_struct *vma, unsigned long address)
+{
+	bool ret;
+
+	ret = !RB_EMPTY_NODE(&vma->vm_rb) &&
+		vma->vm_start <= address && address < vma->vm_end;
 	put_vma(vma);
 	return ret;
 }
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 24/24] powerpc/mm: Add speculative page fault
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

This patch enable the speculative page fault on the PowerPC
architecture.

This will try a speculative page fault without holding the mmap_sem,
if it returns with VM_FAULT_RETRY, the mmap_sem is acquired and the
traditional page fault processing is done.

The speculative path is only tried for multithreaded process as there is no
risk of contention on the mmap_sem otherwise.

Build on if CONFIG_SPECULATIVE_PAGE_FAULT is defined (currently for
BOOK3S_64 && SMP).

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 arch/powerpc/mm/fault.c | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 866446cf2d9a..104f3cc86b51 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -392,6 +392,9 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
 			   unsigned long error_code)
 {
 	struct vm_area_struct * vma;
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	struct vm_area_struct *spf_vma = NULL;
+#endif
 	struct mm_struct *mm = current->mm;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
  	int is_exec = TRAP(regs) == 0x400;
@@ -459,6 +462,20 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
 	if (is_exec)
 		flags |= FAULT_FLAG_INSTRUCTION;
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	if (is_user && (atomic_read(&mm->mm_users) > 1)) {
+		/* let's try a speculative page fault without grabbing the
+		 * mmap_sem.
+		 */
+		fault = handle_speculative_fault(mm, address, flags, &spf_vma);
+		if (!(fault & VM_FAULT_RETRY)) {
+			perf_sw_event(PERF_COUNT_SW_SPF, 1,
+				      regs, address);
+			goto done;
+		}
+	}
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
+
 	/* When running in the kernel we expect faults to occur only to
 	 * addresses in user space.  All other faults represent errors in the
 	 * kernel and should generate an OOPS.  Unfortunately, in the case of an
@@ -489,7 +506,16 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
 		might_sleep();
 	}
 
-	vma = find_vma(mm, address);
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	if (spf_vma) {
+		if (can_reuse_spf_vma(spf_vma, address))
+			vma = spf_vma;
+		else
+			vma =  find_vma(mm, address);
+		spf_vma = NULL;
+	} else
+#endif
+		vma = find_vma(mm, address);
 	if (unlikely(!vma))
 		return bad_area(regs, address);
 	if (likely(vma->vm_start <= address))
@@ -568,6 +594,9 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
 
 	up_read(&current->mm->mmap_sem);
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+done:
+#endif
 	if (unlikely(fault & VM_FAULT_ERROR))
 		return mm_fault_error(regs, address, fault);
 
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 23/24] x86/mm: Add speculative pagefault handling
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

From: Peter Zijlstra <peterz@infradead.org>

Try a speculative fault before acquiring mmap_sem, if it returns with
VM_FAULT_RETRY continue with the mmap_sem acquisition and do the
traditional fault.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

[Clearing of FAULT_FLAG_ALLOW_RETRY is now done in
 handle_speculative_fault()]
[Retry with usual fault path in the case VM_ERROR is returned by
 handle_speculative_fault(). This allows signal to be delivered]
[Don't build SPF call if !CONFIG_SPECULATIVE_PAGE_FAULT]
[Try speculative fault path only for multi threaded processes]
[Try to the VMA fetch during the speculative path in case of retry]
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 arch/x86/mm/fault.c | 38 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 800de815519c..d9f9236ccb9a 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1239,6 +1239,9 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		unsigned long address)
 {
 	struct vm_area_struct *vma;
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	struct vm_area_struct *spf_vma = NULL;
+#endif
 	struct task_struct *tsk;
 	struct mm_struct *mm;
 	int fault, major = 0;
@@ -1336,6 +1339,27 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
 	if (error_code & X86_PF_INSTR)
 		flags |= FAULT_FLAG_INSTRUCTION;
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	if ((error_code & X86_PF_USER) && (atomic_read(&mm->mm_users) > 1)) {
+		fault = handle_speculative_fault(mm, address, flags,
+						 &spf_vma);
+
+		if (!(fault & VM_FAULT_RETRY)) {
+			if (!(fault & VM_FAULT_ERROR)) {
+				perf_sw_event(PERF_COUNT_SW_SPF, 1,
+					      regs, address);
+				goto done;
+			}
+			/*
+			 * In case of error we need the pkey value, but
+			 * can't get it from the spf_vma as it is only returned
+			 * when VM_FAULT_RETRY is returned. So we have to
+			 * retry the page fault with the mmap_sem grabbed.
+			 */
+		}
+	}
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
+
 	/*
 	 * When running in the kernel we expect faults to occur only to
 	 * addresses in user space.  All other faults represent errors in
@@ -1369,7 +1393,16 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		might_sleep();
 	}
 
-	vma = find_vma(mm, address);
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	if (spf_vma) {
+		if (can_reuse_spf_vma(spf_vma, address))
+			vma = spf_vma;
+		else
+			vma = find_vma(mm, address);
+		spf_vma = NULL;
+	} else
+#endif
+		vma = find_vma(mm, address);
 	if (unlikely(!vma)) {
 		bad_area(regs, error_code, address);
 		return;
@@ -1455,6 +1488,9 @@ __do_page_fault(struct pt_regs *regs, unsigned long error_code,
 		return;
 	}
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+done:
+#endif
 	/*
 	 * Major/minor page fault accounting. If any of the events
 	 * returned VM_FAULT_MAJOR, we account it as a major fault.
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 19/24] mm: Adding speculative page fault failure trace events
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

This patch a set of new trace events to collect the speculative page fault
event failures.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 include/trace/events/pagefault.h | 87 ++++++++++++++++++++++++++++++++++++++++
 mm/memory.c                      | 62 ++++++++++++++++++++++------
 2 files changed, 136 insertions(+), 13 deletions(-)
 create mode 100644 include/trace/events/pagefault.h

diff --git a/include/trace/events/pagefault.h b/include/trace/events/pagefault.h
new file mode 100644
index 000000000000..1d793f8c739b
--- /dev/null
+++ b/include/trace/events/pagefault.h
@@ -0,0 +1,87 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM pagefault
+
+#if !defined(_TRACE_PAGEFAULT_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_PAGEFAULT_H
+
+#include <linux/tracepoint.h>
+#include <linux/mm.h>
+
+DECLARE_EVENT_CLASS(spf,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address),
+
+	TP_STRUCT__entry(
+		__field(unsigned long, caller)
+		__field(unsigned long, vm_start)
+		__field(unsigned long, vm_end)
+		__field(unsigned long, address)
+	),
+
+	TP_fast_assign(
+		__entry->caller		= caller;
+		__entry->vm_start	= vma->vm_start;
+		__entry->vm_end		= vma->vm_end;
+		__entry->address	= address;
+	),
+
+	TP_printk("ip:%lx vma:%lx-%lx address:%lx",
+		  __entry->caller, __entry->vm_start, __entry->vm_end,
+		  __entry->address)
+);
+
+DEFINE_EVENT(spf, spf_pte_lock,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+DEFINE_EVENT(spf, spf_vma_changed,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+DEFINE_EVENT(spf, spf_vma_noanon,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+DEFINE_EVENT(spf, spf_vma_notsup,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+DEFINE_EVENT(spf, spf_vma_access,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+DEFINE_EVENT(spf, spf_pmd_changed,
+
+	TP_PROTO(unsigned long caller,
+		 struct vm_area_struct *vma, unsigned long address),
+
+	TP_ARGS(caller, vma, address)
+);
+
+#endif /* _TRACE_PAGEFAULT_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/mm/memory.c b/mm/memory.c
index efc32173264e..2ef686405154 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -80,6 +80,9 @@
 
 #include "internal.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/pagefault.h>
+
 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
 #warning Unfortunate NUMA and NUMA Balancing config, growing page-frame for last_cpupid.
 #endif
@@ -2310,23 +2313,30 @@ static bool pte_spinlock(struct vm_fault *vmf)
 	}
 
 	local_irq_disable();
-	if (vma_has_changed(vmf))
+	if (vma_has_changed(vmf)) {
+		trace_spf_vma_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
+	}
 
 	/*
 	 * We check if the pmd value is still the same to ensure that there
 	 * is a huge collapse operation in progress in our back.
 	 */
 	pmdval = READ_ONCE(*vmf->pmd);
-	if (!pmd_same(pmdval, vmf->orig_pmd))
+	if (!pmd_same(pmdval, vmf->orig_pmd)) {
+		trace_spf_pmd_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
+	}
 
 	vmf->ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
-	if (unlikely(!spin_trylock(vmf->ptl)))
+	if (unlikely(!spin_trylock(vmf->ptl))) {
+		trace_spf_pte_lock(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
+	}
 
 	if (vma_has_changed(vmf)) {
 		spin_unlock(vmf->ptl);
+		trace_spf_vma_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
 	}
 
@@ -2357,16 +2367,20 @@ static bool pte_map_lock(struct vm_fault *vmf)
 	 * block on the PTL and thus we're safe.
 	 */
 	local_irq_disable();
-	if (vma_has_changed(vmf))
+	if (vma_has_changed(vmf)) {
+		trace_spf_vma_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
+	}
 
 	/*
 	 * We check if the pmd value is still the same to ensure that there
 	 * is a huge collapse operation in progress in our back.
 	 */
 	pmdval = READ_ONCE(*vmf->pmd);
-	if (!pmd_same(pmdval, vmf->orig_pmd))
+	if (!pmd_same(pmdval, vmf->orig_pmd)) {
+		trace_spf_pmd_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
+	}
 
 	/*
 	 * Same as pte_offset_map_lock() except that we call
@@ -2379,11 +2393,13 @@ static bool pte_map_lock(struct vm_fault *vmf)
 	pte = pte_offset_map(vmf->pmd, vmf->address);
 	if (unlikely(!spin_trylock(ptl))) {
 		pte_unmap(pte);
+		trace_spf_pte_lock(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
 	}
 
 	if (vma_has_changed(vmf)) {
 		pte_unmap_unlock(pte, ptl);
+		trace_spf_vma_changed(_RET_IP_, vmf->vma, vmf->address);
 		goto out;
 	}
 
@@ -4320,47 +4336,60 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 		return ret;
 
 	seq = raw_read_seqcount(&vma->vm_sequence); /* rmb <-> seqlock,vma_rb_erase() */
-	if (seq & 1)
+	if (seq & 1) {
+		trace_spf_vma_changed(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	/*
 	 * Can't call vm_ops service has we don't know what they would do
 	 * with the VMA.
 	 * This include huge page from hugetlbfs.
 	 */
-	if (vma->vm_ops)
+	if (vma->vm_ops) {
+		trace_spf_vma_notsup(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	/*
 	 * __anon_vma_prepare() requires the mmap_sem to be held
 	 * because vm_next and vm_prev must be safe. This can't be guaranteed
 	 * in the speculative path.
 	 */
-	if (unlikely(!vma->anon_vma))
+	if (unlikely(!vma->anon_vma)) {
+		trace_spf_vma_notsup(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	vmf.vma_flags = READ_ONCE(vma->vm_flags);
 	vmf.vma_page_prot = READ_ONCE(vma->vm_page_prot);
 
 	/* Can't call userland page fault handler in the speculative path */
-	if (unlikely(vmf.vma_flags & VM_UFFD_MISSING))
+	if (unlikely(vmf.vma_flags & VM_UFFD_MISSING)) {
+		trace_spf_vma_notsup(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
-	if (vmf.vma_flags & VM_GROWSDOWN || vmf.vma_flags & VM_GROWSUP)
+	if (vmf.vma_flags & VM_GROWSDOWN || vmf.vma_flags & VM_GROWSUP) {
 		/*
 		 * This could be detected by the check address against VMA's
 		 * boundaries but we want to trace it as not supported instead
 		 * of changed.
 		 */
+		trace_spf_vma_notsup(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	if (address < READ_ONCE(vma->vm_start)
-	    || READ_ONCE(vma->vm_end) <= address)
+	    || READ_ONCE(vma->vm_end) <= address) {
+		trace_spf_vma_changed(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
 				       flags & FAULT_FLAG_INSTRUCTION,
 				       flags & FAULT_FLAG_REMOTE)) {
+		trace_spf_vma_access(_RET_IP_, vma, address);
 		ret = VM_FAULT_SIGSEGV;
 		goto out_put;
 	}
@@ -4368,10 +4397,12 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	/* This is one is required to check that the VMA has write access set */
 	if (flags & FAULT_FLAG_WRITE) {
 		if (unlikely(!(vmf.vma_flags & VM_WRITE))) {
+			trace_spf_vma_access(_RET_IP_, vma, address);
 			ret = VM_FAULT_SIGSEGV;
 			goto out_put;
 		}
 	} else if (unlikely(!(vmf.vma_flags & (VM_READ|VM_EXEC|VM_WRITE)))) {
+		trace_spf_vma_access(_RET_IP_, vma, address);
 		ret = VM_FAULT_SIGSEGV;
 		goto out_put;
 	}
@@ -4384,8 +4415,10 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	pol = __get_vma_policy(vma, address);
 	if (!pol)
 		pol = get_task_policy(current);
-	if (pol && pol->mode == MPOL_INTERLEAVE)
+	if (pol && pol->mode == MPOL_INTERLEAVE) {
+		trace_spf_vma_notsup(_RET_IP_, vma, address);
 		goto out_put;
+	}
 #endif
 
 	/*
@@ -4458,8 +4491,10 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	 * We need to re-validate the VMA after checking the bounds, otherwise
 	 * we might have a false positive on the bounds.
 	 */
-	if (read_seqcount_retry(&vma->vm_sequence, seq))
+	if (read_seqcount_retry(&vma->vm_sequence, seq)) {
+		trace_spf_vma_changed(_RET_IP_, vma, address);
 		goto out_put;
+	}
 
 	mem_cgroup_oom_enable();
 	ret = handle_pte_fault(&vmf);
@@ -4478,6 +4513,7 @@ int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
 	return ret;
 
 out_walk:
+	trace_spf_vma_notsup(_RET_IP_, vma, address);
 	local_irq_enable();
 out_put:
 	put_vma(vma);
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 21/24] perf tools: Add support for the SPF perf event
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

Add support for the new speculative faults event.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 tools/include/uapi/linux/perf_event.h | 1 +
 tools/perf/util/evsel.c               | 1 +
 tools/perf/util/parse-events.c        | 4 ++++
 tools/perf/util/parse-events.l        | 1 +
 tools/perf/util/python.c              | 1 +
 5 files changed, 8 insertions(+)

diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
index e0739a1aa4b2..164383273147 100644
--- a/tools/include/uapi/linux/perf_event.h
+++ b/tools/include/uapi/linux/perf_event.h
@@ -112,6 +112,7 @@ enum perf_sw_ids {
 	PERF_COUNT_SW_EMULATION_FAULTS		= 8,
 	PERF_COUNT_SW_DUMMY			= 9,
 	PERF_COUNT_SW_BPF_OUTPUT		= 10,
+	PERF_COUNT_SW_SPF			= 11,
 
 	PERF_COUNT_SW_MAX,			/* non-ABI */
 };
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 66fa45198a11..7fddb37f44ca 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -438,6 +438,7 @@ const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
 	"alignment-faults",
 	"emulation-faults",
 	"dummy",
+	"speculative-faults",
 };
 
 static const char *__perf_evsel__sw_name(u64 config)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 34589c427e52..2a8189c6d5fc 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -140,6 +140,10 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = {
 		.symbol = "bpf-output",
 		.alias  = "",
 	},
+	[PERF_COUNT_SW_SPF] = {
+		.symbol = "speculative-faults",
+		.alias	= "spf",
+	},
 };
 
 #define __PERF_EVENT_FIELD(config, name) \
diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
index 655ecff636a8..5d6782426b30 100644
--- a/tools/perf/util/parse-events.l
+++ b/tools/perf/util/parse-events.l
@@ -308,6 +308,7 @@ emulation-faults				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EM
 dummy						{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_DUMMY); }
 duration_time					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_DUMMY); }
 bpf-output					{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_BPF_OUTPUT); }
+speculative-faults|spf				{ return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_SPF); }
 
 	/*
 	 * We have to handle the kernel PMU event cycles-ct/cycles-t/mem-loads/mem-stores separately.
diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index b1e999bd21ef..100507d632fa 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -1142,6 +1142,7 @@ static struct {
 	PERF_CONST(COUNT_SW_ALIGNMENT_FAULTS),
 	PERF_CONST(COUNT_SW_EMULATION_FAULTS),
 	PERF_CONST(COUNT_SW_DUMMY),
+	PERF_CONST(COUNT_SW_SPF),
 
 	PERF_CONST(SAMPLE_IP),
 	PERF_CONST(SAMPLE_TID),
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 20/24] perf: Add a speculative page fault sw event
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

Add a new software event to count succeeded speculative page faults.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 include/uapi/linux/perf_event.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h
index e0739a1aa4b2..164383273147 100644
--- a/include/uapi/linux/perf_event.h
+++ b/include/uapi/linux/perf_event.h
@@ -112,6 +112,7 @@ enum perf_sw_ids {
 	PERF_COUNT_SW_EMULATION_FAULTS		= 8,
 	PERF_COUNT_SW_DUMMY			= 9,
 	PERF_COUNT_SW_BPF_OUTPUT		= 10,
+	PERF_COUNT_SW_SPF			= 11,
 
 	PERF_COUNT_SW_MAX,			/* non-ABI */
 };
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 17/24] mm: Protect mm_rb tree with a rwlock
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

This change is inspired by the Peter's proposal patch [1] which was
protecting the VMA using SRCU. Unfortunately, SRCU is not scaling well in
that particular case, and it is introducing major performance degradation
due to excessive scheduling operations.

To allow access to the mm_rb tree without grabbing the mmap_sem, this patch
is protecting it access using a rwlock.  As the mm_rb tree is a O(log n)
search it is safe to protect it using such a lock.  The VMA cache is not
protected by the new rwlock and it should not be used without holding the
mmap_sem.

To allow the picked VMA structure to be used once the rwlock is released, a
use count is added to the VMA structure. When the VMA is allocated it is
set to 1.  Each time the VMA is picked with the rwlock held its use count
is incremented. Each time the VMA is released it is decremented. When the
use count hits zero, this means that the VMA is no more used and should be
freed.

This patch is preparing for 2 kind of VMA access :
 - as usual, under the control of the mmap_sem,
 - without holding the mmap_sem for the speculative page fault handler.

Access done under the control the mmap_sem doesn't require to grab the
rwlock to protect read access to the mm_rb tree, but access in write must
be done under the protection of the rwlock too. This affects inserting and
removing of elements in the RB tree.

The patch is introducing 2 new functions:
 - vma_get() to find a VMA based on an address by holding the new rwlock.
 - vma_put() to release the VMA when its no more used.
These services are designed to be used when access are made to the RB tree
without holding the mmap_sem.

When a VMA is removed from the RB tree, its vma->vm_rb field is cleared and
we rely on the WMB done when releasing the rwlock to serialize the write
with the RMB done in a later patch to check for the VMA's validity.

When free_vma is called, the file associated with the VMA is closed
immediately, but the policy and the file structure remained in used until
the VMA's use count reach 0, which may happens later when exiting an
in progress speculative page fault.

[1] https://patchwork.kernel.org/patch/5108281/

Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 include/linux/mm_types.h |   4 ++
 kernel/fork.c            |   3 ++
 mm/init-mm.c             |   3 ++
 mm/internal.h            |   6 +++
 mm/mmap.c                | 122 ++++++++++++++++++++++++++++++++++-------------
 5 files changed, 106 insertions(+), 32 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 34fde7111e88..28c763ea1036 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -335,6 +335,7 @@ struct vm_area_struct {
 	struct vm_userfaultfd_ctx vm_userfaultfd_ctx;
 #ifdef CONFIG_SPECULATIVE_PAGE_FAULT
 	seqcount_t vm_sequence;
+	atomic_t vm_ref_count;		/* see vma_get(), vma_put() */
 #endif
 } __randomize_layout;
 
@@ -353,6 +354,9 @@ struct kioctx_table;
 struct mm_struct {
 	struct vm_area_struct *mmap;		/* list of VMAs */
 	struct rb_root mm_rb;
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	rwlock_t mm_rb_lock;
+#endif
 	u32 vmacache_seqnum;                   /* per-thread vmacache */
 #ifdef CONFIG_MMU
 	unsigned long (*get_unmapped_area) (struct file *filp,
diff --git a/kernel/fork.c b/kernel/fork.c
index 505195d26744..6c4dc1aa6f17 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -887,6 +887,9 @@ static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct *p,
 	mm->mmap = NULL;
 	mm->mm_rb = RB_ROOT;
 	mm->vmacache_seqnum = 0;
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	rwlock_init(&mm->mm_rb_lock);
+#endif
 	atomic_set(&mm->mm_users, 1);
 	atomic_set(&mm->mm_count, 1);
 	init_rwsem(&mm->mmap_sem);
diff --git a/mm/init-mm.c b/mm/init-mm.c
index f94d5d15ebc0..e71ac37a98c4 100644
--- a/mm/init-mm.c
+++ b/mm/init-mm.c
@@ -17,6 +17,9 @@
 
 struct mm_struct init_mm = {
 	.mm_rb		= RB_ROOT,
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	.mm_rb_lock	= __RW_LOCK_UNLOCKED(init_mm.mm_rb_lock),
+#endif
 	.pgd		= swapper_pg_dir,
 	.mm_users	= ATOMIC_INIT(2),
 	.mm_count	= ATOMIC_INIT(1),
diff --git a/mm/internal.h b/mm/internal.h
index 62d8c34e63d5..fb2667b20f0a 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -40,6 +40,12 @@ void page_writeback_init(void);
 
 int do_swap_page(struct vm_fault *vmf);
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+extern struct vm_area_struct *get_vma(struct mm_struct *mm,
+				      unsigned long addr);
+extern void put_vma(struct vm_area_struct *vma);
+#endif
+
 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 		unsigned long floor, unsigned long ceiling);
 
diff --git a/mm/mmap.c b/mm/mmap.c
index 13c799710a8a..220ba8cb65fc 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -160,6 +160,27 @@ void unlink_file_vma(struct vm_area_struct *vma)
 	}
 }
 
+static void __free_vma(struct vm_area_struct *vma)
+{
+	if (vma->vm_file)
+		fput(vma->vm_file);
+	mpol_put(vma_policy(vma));
+	kmem_cache_free(vm_area_cachep, vma);
+}
+
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+void put_vma(struct vm_area_struct *vma)
+{
+	if (atomic_dec_and_test(&vma->vm_ref_count))
+		__free_vma(vma);
+}
+#else
+static inline void put_vma(struct vm_area_struct *vma)
+{
+	return __free_vma(vma);
+}
+#endif
+
 /*
  * Close a vm structure and free it, returning the next.
  */
@@ -170,10 +191,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
 	might_sleep();
 	if (vma->vm_ops && vma->vm_ops->close)
 		vma->vm_ops->close(vma);
-	if (vma->vm_file)
-		fput(vma->vm_file);
-	mpol_put(vma_policy(vma));
-	kmem_cache_free(vm_area_cachep, vma);
+	put_vma(vma);
 	return next;
 }
 
@@ -393,6 +411,14 @@ static void validate_mm(struct mm_struct *mm)
 #define validate_mm(mm) do { } while (0)
 #endif
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+#define mm_rb_write_lock(mm)	write_lock(&(mm)->mm_rb_lock)
+#define mm_rb_write_unlock(mm)	write_unlock(&(mm)->mm_rb_lock)
+#else
+#define mm_rb_write_lock(mm)	do { } while (0)
+#define mm_rb_write_unlock(mm)	do { } while (0)
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
+
 RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb,
 		     unsigned long, rb_subtree_gap, vma_compute_subtree_gap)
 
@@ -411,26 +437,37 @@ static void vma_gap_update(struct vm_area_struct *vma)
 }
 
 static inline void vma_rb_insert(struct vm_area_struct *vma,
-				 struct rb_root *root)
+				 struct mm_struct *mm)
 {
+	struct rb_root *root = &mm->mm_rb;
+
 	/* All rb_subtree_gap values must be consistent prior to insertion */
 	validate_mm_rb(root, NULL);
 
 	rb_insert_augmented(&vma->vm_rb, root, &vma_gap_callbacks);
 }
 
-static void __vma_rb_erase(struct vm_area_struct *vma, struct rb_root *root)
+static void __vma_rb_erase(struct vm_area_struct *vma, struct mm_struct *mm)
 {
+	struct rb_root *root = &mm->mm_rb;
 	/*
 	 * Note rb_erase_augmented is a fairly large inline function,
 	 * so make sure we instantiate it only once with our desired
 	 * augmented rbtree callbacks.
 	 */
+	mm_rb_write_lock(mm);
 	rb_erase_augmented(&vma->vm_rb, root, &vma_gap_callbacks);
+	mm_rb_write_unlock(mm); /* wmb */
+
+	/*
+	 * Ensure the removal is complete before clearing the node.
+	 * Matched by vma_has_changed()/handle_speculative_fault().
+	 */
+	RB_CLEAR_NODE(&vma->vm_rb);
 }
 
 static __always_inline void vma_rb_erase_ignore(struct vm_area_struct *vma,
-						struct rb_root *root,
+						struct mm_struct *mm,
 						struct vm_area_struct *ignore)
 {
 	/*
@@ -438,21 +475,21 @@ static __always_inline void vma_rb_erase_ignore(struct vm_area_struct *vma,
 	 * with the possible exception of the "next" vma being erased if
 	 * next->vm_start was reduced.
 	 */
-	validate_mm_rb(root, ignore);
+	validate_mm_rb(&mm->mm_rb, ignore);
 
-	__vma_rb_erase(vma, root);
+	__vma_rb_erase(vma, mm);
 }
 
 static __always_inline void vma_rb_erase(struct vm_area_struct *vma,
-					 struct rb_root *root)
+					 struct mm_struct *mm)
 {
 	/*
 	 * All rb_subtree_gap values must be consistent prior to erase,
 	 * with the possible exception of the vma being erased.
 	 */
-	validate_mm_rb(root, vma);
+	validate_mm_rb(&mm->mm_rb, vma);
 
-	__vma_rb_erase(vma, root);
+	__vma_rb_erase(vma, mm);
 }
 
 /*
@@ -558,10 +595,6 @@ void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma,
 	else
 		mm->highest_vm_end = vm_end_gap(vma);
 
-#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
-	seqcount_init(&vma->vm_sequence);
-#endif
-
 	/*
 	 * vma->vm_prev wasn't known when we followed the rbtree to find the
 	 * correct insertion point for that vma. As a result, we could not
@@ -571,10 +604,15 @@ void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma,
 	 * immediately update the gap to the correct value. Finally we
 	 * rebalance the rbtree after all augmented values have been set.
 	 */
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	atomic_set(&vma->vm_ref_count, 1);
+#endif
+	mm_rb_write_lock(mm);
 	rb_link_node(&vma->vm_rb, rb_parent, rb_link);
 	vma->rb_subtree_gap = 0;
 	vma_gap_update(vma);
-	vma_rb_insert(vma, &mm->mm_rb);
+	vma_rb_insert(vma, mm);
+	mm_rb_write_unlock(mm);
 }
 
 static void __vma_link_file(struct vm_area_struct *vma)
@@ -650,7 +688,7 @@ static __always_inline void __vma_unlink_common(struct mm_struct *mm,
 {
 	struct vm_area_struct *next;
 
-	vma_rb_erase_ignore(vma, &mm->mm_rb, ignore);
+	vma_rb_erase_ignore(vma, mm, ignore);
 	next = vma->vm_next;
 	if (has_prev)
 		prev->vm_next = next;
@@ -923,16 +961,13 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
 	}
 
 	if (remove_next) {
-		if (file) {
+		if (file)
 			uprobe_munmap(next, next->vm_start, next->vm_end);
-			fput(file);
-		}
 		if (next->anon_vma)
 			anon_vma_merge(vma, next);
 		mm->map_count--;
-		mpol_put(vma_policy(next));
 		vm_raw_write_end(next);
-		kmem_cache_free(vm_area_cachep, next);
+		put_vma(next);
 		/*
 		 * In mprotect's case 6 (see comments on vma_merge),
 		 * we must remove another next too. It would clutter
@@ -2182,15 +2217,11 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 EXPORT_SYMBOL(get_unmapped_area);
 
 /* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
-struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
+static struct vm_area_struct *__find_vma(struct mm_struct *mm,
+					 unsigned long addr)
 {
 	struct rb_node *rb_node;
-	struct vm_area_struct *vma;
-
-	/* Check the cache first. */
-	vma = vmacache_find(mm, addr);
-	if (likely(vma))
-		return vma;
+	struct vm_area_struct *vma = NULL;
 
 	rb_node = mm->mm_rb.rb_node;
 
@@ -2208,13 +2239,40 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 			rb_node = rb_node->rb_right;
 	}
 
+	return vma;
+}
+
+struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
+{
+	struct vm_area_struct *vma;
+
+	/* Check the cache first. */
+	vma = vmacache_find(mm, addr);
+	if (likely(vma))
+		return vma;
+
+	vma = __find_vma(mm, addr);
 	if (vma)
 		vmacache_update(addr, vma);
 	return vma;
 }
-
 EXPORT_SYMBOL(find_vma);
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+struct vm_area_struct *get_vma(struct mm_struct *mm, unsigned long addr)
+{
+	struct vm_area_struct *vma = NULL;
+
+	read_lock(&mm->mm_rb_lock);
+	vma = __find_vma(mm, addr);
+	if (vma)
+		atomic_inc(&vma->vm_ref_count);
+	read_unlock(&mm->mm_rb_lock);
+
+	return vma;
+}
+#endif
+
 /*
  * Same as find_vma, but also return a pointer to the previous VMA in *pprev.
  */
@@ -2582,7 +2640,7 @@ detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma,
 	insertion_point = (prev ? &prev->vm_next : &mm->mmap);
 	vma->vm_prev = NULL;
 	do {
-		vma_rb_erase(vma, &mm->mm_rb);
+		vma_rb_erase(vma, mm);
 		mm->map_count--;
 		tail_vma = vma;
 		vma = vma->vm_next;
-- 
2.7.4

^ permalink raw reply related

* [PATCH v8 18/24] mm: Provide speculative fault infrastructure
From: Laurent Dufour @ 2018-02-16 15:25 UTC (permalink / raw)
  To: paulmck, peterz, akpm, kirill, ak, mhocko, dave, jack,
	Matthew Wilcox, benh, mpe, paulus, Thomas Gleixner, Ingo Molnar,
	hpa, Will Deacon, Sergey Senozhatsky, Andrea Arcangeli,
	Alexei Starovoitov, kemi.wang, sergey.senozhatsky.work,
	Daniel Jordan
  Cc: linux-kernel, linux-mm, haren, khandual, npiggin, bsingharora,
	Tim Chen, linuxppc-dev, x86
In-Reply-To: <1518794738-4186-1-git-send-email-ldufour@linux.vnet.ibm.com>

From: Peter Zijlstra <peterz@infradead.org>

Provide infrastructure to do a speculative fault (not holding
mmap_sem).

The not holding of mmap_sem means we can race against VMA
change/removal and page-table destruction. We use the SRCU VMA freeing
to keep the VMA around. We use the VMA seqcount to detect change
(including umapping / page-table deletion) and we use gup_fast() style
page-table walking to deal with page-table races.

Once we've obtained the page and are ready to update the PTE, we
validate if the state we started the fault with is still valid, if
not, we'll fail the fault with VM_FAULT_RETRY, otherwise we update the
PTE and we're done.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

[Manage the newly introduced pte_spinlock() for speculative page
 fault to fail if the VMA is touched in our back]
[Rename vma_is_dead() to vma_has_changed() and declare it here]
[Fetch p4d and pud]
[Set vmd.sequence in __handle_mm_fault()]
[Abort speculative path when handle_userfault() has to be called]
[Add additional VMA's flags checks in handle_speculative_fault()]
[Clear FAULT_FLAG_ALLOW_RETRY in handle_speculative_fault()]
[Don't set vmf->pte and vmf->ptl if pte_map_lock() failed]
[Remove warning comment about waiting for !seq&1 since we don't want
 to wait]
[Remove warning about no huge page support, mention it explictly]
[Don't call do_fault() in the speculative path as __do_fault() calls
 vma->vm_ops->fault() which may want to release mmap_sem]
[Only vm_fault pointer argument for vma_has_changed()]
[Fix check against huge page, calling pmd_trans_huge()]
[Use READ_ONCE() when reading VMA's fields in the speculative path]
[Explicitly check for __HAVE_ARCH_PTE_SPECIAL as we can't support for
 processing done in vm_normal_page()]
[Check that vma->anon_vma is already set when starting the speculative
 path]
[Check for memory policy as we can't support MPOL_INTERLEAVE case due to
 the processing done in mpol_misplaced()]
[Don't support VMA growing up or down]
[Move check on vm_sequence just before calling handle_pte_fault()]
[Don't build SPF services if !CONFIG_SPECULATIVE_PAGE_FAULT]
[Add mem cgroup oom check]
[Use READ_ONCE to access p*d entries]
[Replace deprecated ACCESS_ONCE() by READ_ONCE() in vma_has_changed()]
[Don't fetch pte again in handle_pte_fault() when running the speculative
 path]
[Check PMD against concurrent collapsing operation]
[Try spin lock the pte during the speculative path to avoid deadlock with
 other CPU's invalidating the TLB and requiring this CPU to catch the
 inter processor's interrupt]
Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
---
 include/linux/hugetlb_inline.h |   2 +-
 include/linux/mm.h             |   8 +
 include/linux/pagemap.h        |   4 +-
 mm/internal.h                  |  16 +-
 mm/memory.c                    | 334 ++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 356 insertions(+), 8 deletions(-)

diff --git a/include/linux/hugetlb_inline.h b/include/linux/hugetlb_inline.h
index 0660a03d37d9..9e25283d6fc9 100644
--- a/include/linux/hugetlb_inline.h
+++ b/include/linux/hugetlb_inline.h
@@ -8,7 +8,7 @@
 
 static inline bool is_vm_hugetlb_page(struct vm_area_struct *vma)
 {
-	return !!(vma->vm_flags & VM_HUGETLB);
+	return !!(READ_ONCE(vma->vm_flags) & VM_HUGETLB);
 }
 
 #else
diff --git a/include/linux/mm.h b/include/linux/mm.h
index d5f17fcd2c32..c383a4e2ceb3 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -331,6 +331,10 @@ struct vm_fault {
 	gfp_t gfp_mask;			/* gfp mask to be used for allocations */
 	pgoff_t pgoff;			/* Logical page offset based on vma */
 	unsigned long address;		/* Faulting virtual address */
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	unsigned int sequence;
+	pmd_t orig_pmd;			/* value of PMD at the time of fault */
+#endif
 	pmd_t *pmd;			/* Pointer to pmd entry matching
 					 * the 'address' */
 	pud_t *pud;			/* Pointer to pud entry matching
@@ -1349,6 +1353,10 @@ int invalidate_inode_page(struct page *page);
 #ifdef CONFIG_MMU
 extern int handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
 		unsigned int flags);
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+extern int handle_speculative_fault(struct mm_struct *mm,
+				    unsigned long address, unsigned int flags);
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
 extern int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm,
 			    unsigned long address, unsigned int fault_flags,
 			    bool *unlocked);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 34ce3ebf97d5..70e4d2688e7b 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -456,8 +456,8 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma,
 	pgoff_t pgoff;
 	if (unlikely(is_vm_hugetlb_page(vma)))
 		return linear_hugepage_index(vma, address);
-	pgoff = (address - vma->vm_start) >> PAGE_SHIFT;
-	pgoff += vma->vm_pgoff;
+	pgoff = (address - READ_ONCE(vma->vm_start)) >> PAGE_SHIFT;
+	pgoff += READ_ONCE(vma->vm_pgoff);
 	return pgoff;
 }
 
diff --git a/mm/internal.h b/mm/internal.h
index fb2667b20f0a..10b188c87fa4 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -44,7 +44,21 @@ int do_swap_page(struct vm_fault *vmf);
 extern struct vm_area_struct *get_vma(struct mm_struct *mm,
 				      unsigned long addr);
 extern void put_vma(struct vm_area_struct *vma);
-#endif
+
+static inline bool vma_has_changed(struct vm_fault *vmf)
+{
+	int ret = RB_EMPTY_NODE(&vmf->vma->vm_rb);
+	unsigned int seq = READ_ONCE(vmf->vma->vm_sequence.sequence);
+
+	/*
+	 * Matches both the wmb in write_seqlock_{begin,end}() and
+	 * the wmb in vma_rb_erase().
+	 */
+	smp_rmb();
+
+	return ret || seq != vmf->sequence;
+}
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
 
 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 		unsigned long floor, unsigned long ceiling);
diff --git a/mm/memory.c b/mm/memory.c
index 67de327c7262..efc32173264e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -769,7 +769,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 	if (page)
 		dump_page(page, "bad pte");
 	pr_alert("addr:%p vm_flags:%08lx anon_vma:%p mapping:%p index:%lx\n",
-		 (void *)addr, vma->vm_flags, vma->anon_vma, mapping, index);
+		 (void *)addr, READ_ONCE(vma->vm_flags), vma->anon_vma,
+		 mapping, index);
 	pr_alert("file:%pD fault:%pf mmap:%pf readpage:%pf\n",
 		 vma->vm_file,
 		 vma->vm_ops ? vma->vm_ops->fault : NULL,
@@ -2295,19 +2296,119 @@ int apply_to_page_range(struct mm_struct *mm, unsigned long addr,
 }
 EXPORT_SYMBOL_GPL(apply_to_page_range);
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
 static bool pte_spinlock(struct vm_fault *vmf)
 {
+	bool ret = false;
+	pmd_t pmdval;
+
+	/* Check if vma is still valid */
+	if (!(vmf->flags & FAULT_FLAG_SPECULATIVE)) {
+		vmf->ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
+		spin_lock(vmf->ptl);
+		return true;
+	}
+
+	local_irq_disable();
+	if (vma_has_changed(vmf))
+		goto out;
+
+	/*
+	 * We check if the pmd value is still the same to ensure that there
+	 * is a huge collapse operation in progress in our back.
+	 */
+	pmdval = READ_ONCE(*vmf->pmd);
+	if (!pmd_same(pmdval, vmf->orig_pmd))
+		goto out;
+
+	vmf->ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
+	if (unlikely(!spin_trylock(vmf->ptl)))
+		goto out;
+
+	if (vma_has_changed(vmf)) {
+		spin_unlock(vmf->ptl);
+		goto out;
+	}
+
+	ret = true;
+out:
+	local_irq_enable();
+	return ret;
+}
+
+static bool pte_map_lock(struct vm_fault *vmf)
+{
+	bool ret = false;
+	pte_t *pte;
+	pmd_t pmdval;
+	spinlock_t *ptl;
+
+	if (!(vmf->flags & FAULT_FLAG_SPECULATIVE)) {
+		vmf->pte = pte_offset_map_lock(vmf->vma->vm_mm, vmf->pmd,
+					       vmf->address, &vmf->ptl);
+		return true;
+	}
+
+	/*
+	 * The first vma_has_changed() guarantees the page-tables are still
+	 * valid, having IRQs disabled ensures they stay around, hence the
+	 * second vma_has_changed() to make sure they are still valid once
+	 * we've got the lock. After that a concurrent zap_pte_range() will
+	 * block on the PTL and thus we're safe.
+	 */
+	local_irq_disable();
+	if (vma_has_changed(vmf))
+		goto out;
+
+	/*
+	 * We check if the pmd value is still the same to ensure that there
+	 * is a huge collapse operation in progress in our back.
+	 */
+	pmdval = READ_ONCE(*vmf->pmd);
+	if (!pmd_same(pmdval, vmf->orig_pmd))
+		goto out;
+
+	/*
+	 * Same as pte_offset_map_lock() except that we call
+	 * spin_trylock() in place of spin_lock() to avoid race with
+	 * unmap path which may have the lock and wait for this CPU
+	 * to invalidate TLB but this CPU has irq disabled.
+	 * Since we are in a speculative patch, accept it could fail
+	 */
+	ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
+	pte = pte_offset_map(vmf->pmd, vmf->address);
+	if (unlikely(!spin_trylock(ptl))) {
+		pte_unmap(pte);
+		goto out;
+	}
+
+	if (vma_has_changed(vmf)) {
+		pte_unmap_unlock(pte, ptl);
+		goto out;
+	}
+
+	vmf->pte = pte;
+	vmf->ptl = ptl;
+	ret = true;
+out:
+	local_irq_enable();
+	return ret;
+}
+#else
+static inline bool pte_spinlock(struct vm_fault *vmf)
+{
 	vmf->ptl = pte_lockptr(vmf->vma->vm_mm, vmf->pmd);
 	spin_lock(vmf->ptl);
 	return true;
 }
 
-static bool pte_map_lock(struct vm_fault *vmf)
+static inline bool pte_map_lock(struct vm_fault *vmf)
 {
 	vmf->pte = pte_offset_map_lock(vmf->vma->vm_mm, vmf->pmd,
 				       vmf->address, &vmf->ptl);
 	return true;
 }
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
 
 /*
  * handle_pte_fault chooses page fault handler according to an entry which was
@@ -3207,6 +3308,14 @@ static int do_anonymous_page(struct vm_fault *vmf)
 		ret = check_stable_address_space(vma->vm_mm);
 		if (ret)
 			goto unlock;
+		/*
+		 * Don't call the userfaultfd during the speculative path.
+		 * We already checked for the VMA to not be managed through
+		 * userfaultfd, but it may be set in our back once we have lock
+		 * the pte. In such a case we can ignore it this time.
+		 */
+		if (vmf->flags & FAULT_FLAG_SPECULATIVE)
+			goto setpte;
 		/* Deliver the page fault to userland, check inside PT lock */
 		if (userfaultfd_missing(vma)) {
 			pte_unmap_unlock(vmf->pte, vmf->ptl);
@@ -3249,7 +3358,7 @@ static int do_anonymous_page(struct vm_fault *vmf)
 		goto release;
 
 	/* Deliver the page fault to userland, check inside PT lock */
-	if (userfaultfd_missing(vma)) {
+	if (!(vmf->flags & FAULT_FLAG_SPECULATIVE) && userfaultfd_missing(vma)) {
 		pte_unmap_unlock(vmf->pte, vmf->ptl);
 		mem_cgroup_cancel_charge(page, memcg, false);
 		put_page(page);
@@ -3992,13 +4101,22 @@ static int handle_pte_fault(struct vm_fault *vmf)
 
 	if (unlikely(pmd_none(*vmf->pmd))) {
 		/*
+		 * In the case of the speculative page fault handler we abort
+		 * the speculative path immediately as the pmd is probably
+		 * in the way to be converted in a huge one. We will try
+		 * again holding the mmap_sem (which implies that the collapse
+		 * operation is done).
+		 */
+		if (vmf->flags & FAULT_FLAG_SPECULATIVE)
+			return VM_FAULT_RETRY;
+		/*
 		 * Leave __pte_alloc() until later: because vm_ops->fault may
 		 * want to allocate huge page, and if we expose page table
 		 * for an instant, it will be difficult to retract from
 		 * concurrent faults and from rmap lookups.
 		 */
 		vmf->pte = NULL;
-	} else {
+	} else if (!(vmf->flags & FAULT_FLAG_SPECULATIVE)) {
 		/* See comment in pte_alloc_one_map() */
 		if (pmd_devmap_trans_unstable(vmf->pmd))
 			return 0;
@@ -4007,6 +4125,9 @@ static int handle_pte_fault(struct vm_fault *vmf)
 		 * pmd from under us anymore at this point because we hold the
 		 * mmap_sem read mode and khugepaged takes it in write mode.
 		 * So now it's safe to run pte_offset_map().
+		 * This is not applicable to the speculative page fault handler
+		 * but in that case, the pte is fetched earlier in
+		 * handle_speculative_fault().
 		 */
 		vmf->pte = pte_offset_map(vmf->pmd, vmf->address);
 		vmf->orig_pte = *vmf->pte;
@@ -4029,6 +4150,8 @@ static int handle_pte_fault(struct vm_fault *vmf)
 	if (!vmf->pte) {
 		if (vma_is_anonymous(vmf->vma))
 			return do_anonymous_page(vmf);
+		else if (vmf->flags & FAULT_FLAG_SPECULATIVE)
+			return VM_FAULT_RETRY;
 		else
 			return do_fault(vmf);
 	}
@@ -4126,6 +4249,9 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
 	vmf.pmd = pmd_alloc(mm, vmf.pud, address);
 	if (!vmf.pmd)
 		return VM_FAULT_OOM;
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+	vmf.sequence = raw_read_seqcount(&vma->vm_sequence);
+#endif
 	if (pmd_none(*vmf.pmd) && transparent_hugepage_enabled(vma)) {
 		ret = create_huge_pmd(&vmf);
 		if (!(ret & VM_FAULT_FALLBACK))
@@ -4159,6 +4285,206 @@ static int __handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
 	return handle_pte_fault(&vmf);
 }
 
+#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
+
+#ifndef __HAVE_ARCH_PTE_SPECIAL
+/* This is required by vm_normal_page() */
+#error "Speculative page fault handler requires __HAVE_ARCH_PTE_SPECIAL"
+#endif
+
+/*
+ * vm_normal_page() adds some processing which should be done while
+ * hodling the mmap_sem.
+ */
+int handle_speculative_fault(struct mm_struct *mm, unsigned long address,
+			     unsigned int flags)
+{
+	struct vm_fault vmf = {
+		.address = address,
+	};
+	pgd_t *pgd, pgdval;
+	p4d_t *p4d, p4dval;
+	pud_t pudval;
+	int seq, ret = VM_FAULT_RETRY;
+	struct vm_area_struct *vma;
+#ifdef CONFIG_NUMA
+	struct mempolicy *pol;
+#endif
+
+	/* Clear flags that may lead to release the mmap_sem to retry */
+	flags &= ~(FAULT_FLAG_ALLOW_RETRY|FAULT_FLAG_KILLABLE);
+	flags |= FAULT_FLAG_SPECULATIVE;
+
+	vma = get_vma(mm, address);
+	if (!vma)
+		return ret;
+
+	seq = raw_read_seqcount(&vma->vm_sequence); /* rmb <-> seqlock,vma_rb_erase() */
+	if (seq & 1)
+		goto out_put;
+
+	/*
+	 * Can't call vm_ops service has we don't know what they would do
+	 * with the VMA.
+	 * This include huge page from hugetlbfs.
+	 */
+	if (vma->vm_ops)
+		goto out_put;
+
+	/*
+	 * __anon_vma_prepare() requires the mmap_sem to be held
+	 * because vm_next and vm_prev must be safe. This can't be guaranteed
+	 * in the speculative path.
+	 */
+	if (unlikely(!vma->anon_vma))
+		goto out_put;
+
+	vmf.vma_flags = READ_ONCE(vma->vm_flags);
+	vmf.vma_page_prot = READ_ONCE(vma->vm_page_prot);
+
+	/* Can't call userland page fault handler in the speculative path */
+	if (unlikely(vmf.vma_flags & VM_UFFD_MISSING))
+		goto out_put;
+
+	if (vmf.vma_flags & VM_GROWSDOWN || vmf.vma_flags & VM_GROWSUP)
+		/*
+		 * This could be detected by the check address against VMA's
+		 * boundaries but we want to trace it as not supported instead
+		 * of changed.
+		 */
+		goto out_put;
+
+	if (address < READ_ONCE(vma->vm_start)
+	    || READ_ONCE(vma->vm_end) <= address)
+		goto out_put;
+
+	if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+				       flags & FAULT_FLAG_INSTRUCTION,
+				       flags & FAULT_FLAG_REMOTE)) {
+		ret = VM_FAULT_SIGSEGV;
+		goto out_put;
+	}
+
+	/* This is one is required to check that the VMA has write access set */
+	if (flags & FAULT_FLAG_WRITE) {
+		if (unlikely(!(vmf.vma_flags & VM_WRITE))) {
+			ret = VM_FAULT_SIGSEGV;
+			goto out_put;
+		}
+	} else if (unlikely(!(vmf.vma_flags & (VM_READ|VM_EXEC|VM_WRITE)))) {
+		ret = VM_FAULT_SIGSEGV;
+		goto out_put;
+	}
+
+#ifdef CONFIG_NUMA
+	/*
+	 * MPOL_INTERLEAVE implies additional check in mpol_misplaced() which
+	 * are not compatible with the speculative page fault processing.
+	 */
+	pol = __get_vma_policy(vma, address);
+	if (!pol)
+		pol = get_task_policy(current);
+	if (pol && pol->mode == MPOL_INTERLEAVE)
+		goto out_put;
+#endif
+
+	/*
+	 * Do a speculative lookup of the PTE entry.
+	 */
+	local_irq_disable();
+	pgd = pgd_offset(mm, address);
+	pgdval = READ_ONCE(*pgd);
+	if (pgd_none(pgdval) || unlikely(pgd_bad(pgdval)))
+		goto out_walk;
+
+	p4d = p4d_offset(pgd, address);
+	p4dval = READ_ONCE(*p4d);
+	if (p4d_none(p4dval) || unlikely(p4d_bad(p4dval)))
+		goto out_walk;
+
+	vmf.pud = pud_offset(p4d, address);
+	pudval = READ_ONCE(*vmf.pud);
+	if (pud_none(pudval) || unlikely(pud_bad(pudval)))
+		goto out_walk;
+
+	/* Huge pages at PUD level are not supported. */
+	if (unlikely(pud_trans_huge(pudval)))
+		goto out_walk;
+
+	vmf.pmd = pmd_offset(vmf.pud, address);
+	vmf.orig_pmd = READ_ONCE(*vmf.pmd);
+	/*
+	 * pmd_none could mean that a hugepage collapse is in progress
+	 * in our back as collapse_huge_page() mark it before
+	 * invalidating the pte (which is done once the IPI is catched
+	 * by all CPU and we have interrupt disabled).
+	 * For this reason we cannot handle THP in a speculative way since we
+	 * can't safely indentify an in progress collapse operation done in our
+	 * back on that PMD.
+	 * Regarding the order of the following checks, see comment in
+	 * pmd_devmap_trans_unstable()
+	 */
+	if (unlikely(pmd_devmap(vmf.orig_pmd) ||
+		     pmd_none(vmf.orig_pmd) || pmd_trans_huge(vmf.orig_pmd) ||
+		     is_swap_pmd(vmf.orig_pmd)))
+		goto out_walk;
+
+	/*
+	 * The above does not allocate/instantiate page-tables because doing so
+	 * would lead to the possibility of instantiating page-tables after
+	 * free_pgtables() -- and consequently leaking them.
+	 *
+	 * The result is that we take at least one !speculative fault per PMD
+	 * in order to instantiate it.
+	 */
+
+	vmf.pte = pte_offset_map(vmf.pmd, address);
+	vmf.orig_pte = READ_ONCE(*vmf.pte);
+	barrier(); /* See comment in handle_pte_fault() */
+	if (pte_none(vmf.orig_pte)) {
+		pte_unmap(vmf.pte);
+		vmf.pte = NULL;
+	}
+
+	vmf.vma = vma;
+	vmf.pgoff = linear_page_index(vma, address);
+	vmf.gfp_mask = __get_fault_gfp_mask(vma);
+	vmf.sequence = seq;
+	vmf.flags = flags;
+
+	local_irq_enable();
+
+	/*
+	 * We need to re-validate the VMA after checking the bounds, otherwise
+	 * we might have a false positive on the bounds.
+	 */
+	if (read_seqcount_retry(&vma->vm_sequence, seq))
+		goto out_put;
+
+	mem_cgroup_oom_enable();
+	ret = handle_pte_fault(&vmf);
+	mem_cgroup_oom_disable();
+
+	put_vma(vma);
+
+	/*
+	 * The task may have entered a memcg OOM situation but
+	 * if the allocation error was handled gracefully (no
+	 * VM_FAULT_OOM), there is no need to kill anything.
+	 * Just clean up the OOM state peacefully.
+	 */
+	if (task_in_memcg_oom(current) && !(ret & VM_FAULT_OOM))
+		mem_cgroup_oom_synchronize(false);
+	return ret;
+
+out_walk:
+	local_irq_enable();
+out_put:
+	put_vma(vma);
+	return ret;
+}
+#endif /* CONFIG_SPECULATIVE_PAGE_FAULT */
+
 /*
  * By the time we get here, we already hold the mm semaphore
  *
-- 
2.7.4

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