From: David Hildenbrand <dahi@linux.vnet.ibm.com>
To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org
Cc: benh@kernel.crashing.org, paulus@samba.org,
akpm@linux-foundation.org, heiko.carstens@de.ibm.com,
dahi@linux.vnet.ibm.com, schwidefsky@de.ibm.com,
borntraeger@de.ibm.com, mst@redhat.com, tglx@linutronix.de,
David.Laight@ACULAB.COM, peterz@infradead.org, hughd@google.com,
hocko@suse.cz
Subject: [PATCH v2 1/5] uaccess: add pagefault_count to thread_info
Date: Wed, 10 Dec 2014 15:23:30 +0100 [thread overview]
Message-ID: <1418221414-60110-2-git-send-email-dahi@linux.vnet.ibm.com> (raw)
In-Reply-To: <1418221414-60110-1-git-send-email-dahi@linux.vnet.ibm.com>
This patch adds the pagefault_count to the thread_info of all
architectures. It will be used to count the pagefault_disable() levels
on a per-thread basis.
We are not reusing the preempt_count as this is per cpu on x86 and we want to
demangle pagefault_disable() from preemption in the future.
The new counter is added directly below the preempt_count, except for archs
relying on a manual calculation of asm offsets - to minimize the changes.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
---
arch/alpha/include/asm/thread_info.h | 1 +
arch/arc/include/asm/thread_info.h | 1 +
arch/arm/include/asm/thread_info.h | 1 +
arch/arm64/include/asm/thread_info.h | 1 +
arch/avr32/include/asm/thread_info.h | 1 +
arch/blackfin/include/asm/thread_info.h | 1 +
arch/c6x/include/asm/thread_info.h | 1 +
arch/cris/include/asm/thread_info.h | 1 +
arch/frv/include/asm/thread_info.h | 1 +
arch/hexagon/include/asm/thread_info.h | 1 +
arch/ia64/include/asm/thread_info.h | 1 +
arch/m32r/include/asm/thread_info.h | 1 +
arch/m68k/include/asm/thread_info.h | 1 +
arch/metag/include/asm/thread_info.h | 1 +
arch/microblaze/include/asm/thread_info.h | 1 +
arch/mips/include/asm/thread_info.h | 1 +
arch/mn10300/include/asm/thread_info.h | 1 +
arch/openrisc/include/asm/thread_info.h | 1 +
arch/parisc/include/asm/thread_info.h | 1 +
arch/powerpc/include/asm/thread_info.h | 1 +
arch/s390/include/asm/thread_info.h | 1 +
arch/score/include/asm/thread_info.h | 1 +
arch/sh/include/asm/thread_info.h | 1 +
arch/sparc/include/asm/thread_info_32.h | 1 +
arch/sparc/include/asm/thread_info_64.h | 1 +
arch/tile/include/asm/thread_info.h | 1 +
arch/um/include/asm/thread_info.h | 1 +
arch/unicore32/include/asm/thread_info.h | 1 +
arch/x86/include/asm/thread_info.h | 1 +
arch/xtensa/include/asm/thread_info.h | 1 +
30 files changed, 30 insertions(+)
diff --git a/arch/alpha/include/asm/thread_info.h b/arch/alpha/include/asm/thread_info.h
index 48bbea6..1830671 100644
--- a/arch/alpha/include/asm/thread_info.h
+++ b/arch/alpha/include/asm/thread_info.h
@@ -22,6 +22,7 @@ struct thread_info {
mm_segment_t addr_limit; /* thread address space */
unsigned cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
unsigned int status; /* thread-synchronous flags */
int bpt_nsaved;
diff --git a/arch/arc/include/asm/thread_info.h b/arch/arc/include/asm/thread_info.h
index 02bc5ec..2fde704 100644
--- a/arch/arc/include/asm/thread_info.h
+++ b/arch/arc/include/asm/thread_info.h
@@ -41,6 +41,7 @@
struct thread_info {
unsigned long flags; /* low level flags */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count; /* pagefault_disable() levels */
struct task_struct *task; /* main task structure */
mm_segment_t addr_limit; /* thread address space */
struct exec_domain *exec_domain;/* execution domain */
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index ce73ab6..bf47d2d 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -51,6 +51,7 @@ struct cpu_context_save {
struct thread_info {
unsigned long flags; /* low level flags */
int preempt_count; /* 0 => preemptable, <0 => bug */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* address limit */
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index 459bf8e..2469f15 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -50,6 +50,7 @@ struct thread_info {
struct exec_domain *exec_domain; /* execution domain */
struct restart_block restart_block;
int preempt_count; /* 0 => preemptable, <0 => bug */
+ int pagefault_count;/* pagefault_disable() levels */
int cpu; /* cpu */
};
diff --git a/arch/avr32/include/asm/thread_info.h b/arch/avr32/include/asm/thread_info.h
index a978f3f..0c1d6f7 100644
--- a/arch/avr32/include/asm/thread_info.h
+++ b/arch/avr32/include/asm/thread_info.h
@@ -25,6 +25,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
__u32 cpu;
__s32 preempt_count; /* 0 => preemptable, <0 => BUG */
+ __s32 pagefault_count;/* pagefault_disable() levels */
__u32 rar_saved; /* return address... */
__u32 rsr_saved; /* ...and status register
saved by debug handler
diff --git a/arch/blackfin/include/asm/thread_info.h b/arch/blackfin/include/asm/thread_info.h
index 55f473b..3ba26aa 100644
--- a/arch/blackfin/include/asm/thread_info.h
+++ b/arch/blackfin/include/asm/thread_info.h
@@ -41,6 +41,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
int cpu; /* cpu we're on */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count; /* pagefault_disable() levels */
mm_segment_t addr_limit; /* address limit */
struct restart_block restart_block;
#ifndef CONFIG_SMP
diff --git a/arch/c6x/include/asm/thread_info.h b/arch/c6x/include/asm/thread_info.h
index d4e9ef8..6b2dcac 100644
--- a/arch/c6x/include/asm/thread_info.h
+++ b/arch/c6x/include/asm/thread_info.h
@@ -44,6 +44,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
int cpu; /* cpu we're on */
int preempt_count; /* 0 = preemptable, <0 = BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
};
diff --git a/arch/cris/include/asm/thread_info.h b/arch/cris/include/asm/thread_info.h
index 55dede1..3356902 100644
--- a/arch/cris/include/asm/thread_info.h
+++ b/arch/cris/include/asm/thread_info.h
@@ -32,6 +32,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
__u32 tls; /* TLS for this thread */
mm_segment_t addr_limit; /* thread address space:
diff --git a/arch/frv/include/asm/thread_info.h b/arch/frv/include/asm/thread_info.h
index af29e17..79a97ee 100644
--- a/arch/frv/include/asm/thread_info.h
+++ b/arch/frv/include/asm/thread_info.h
@@ -36,6 +36,7 @@ struct thread_info {
unsigned long status; /* thread-synchronous flags */
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space:
* 0-0xBFFFFFFF for user-thead
diff --git a/arch/hexagon/include/asm/thread_info.h b/arch/hexagon/include/asm/thread_info.h
index a59dad3..d54042e 100644
--- a/arch/hexagon/include/asm/thread_info.h
+++ b/arch/hexagon/include/asm/thread_info.h
@@ -51,6 +51,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
__u32 cpu; /* current cpu */
int preempt_count; /* 0=>preemptible,<0=>BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* segmentation sux */
/*
* used for syscalls somehow;
diff --git a/arch/ia64/include/asm/thread_info.h b/arch/ia64/include/asm/thread_info.h
index 5b17418..14f128c 100644
--- a/arch/ia64/include/asm/thread_info.h
+++ b/arch/ia64/include/asm/thread_info.h
@@ -27,6 +27,7 @@ struct thread_info {
__u32 status; /* Thread synchronous flags */
mm_segment_t addr_limit; /* user-level address space limit */
int preempt_count; /* 0=premptable, <0=BUG; will also serve as bh-counter */
+ int pagefault_count; /* pagefault_disable() levels */
struct restart_block restart_block;
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
__u64 ac_stamp;
diff --git a/arch/m32r/include/asm/thread_info.h b/arch/m32r/include/asm/thread_info.h
index 0017170..bf14efb 100644
--- a/arch/m32r/include/asm/thread_info.h
+++ b/arch/m32r/include/asm/thread_info.h
@@ -35,6 +35,7 @@ struct thread_info {
0-0xFFFFFFFF for kernel-thread
*/
struct restart_block restart_block;
+ int pagefault_count;/* pagefault_disable() levels */
__u8 supervisor_stack[0];
};
diff --git a/arch/m68k/include/asm/thread_info.h b/arch/m68k/include/asm/thread_info.h
index 21a4784..5a6a203 100644
--- a/arch/m68k/include/asm/thread_info.h
+++ b/arch/m68k/include/asm/thread_info.h
@@ -29,6 +29,7 @@ struct thread_info {
struct exec_domain *exec_domain; /* execution domain */
mm_segment_t addr_limit; /* thread address space */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
__u32 cpu; /* should always be 0 on m68k */
unsigned long tp_value; /* thread pointer */
struct restart_block restart_block;
diff --git a/arch/metag/include/asm/thread_info.h b/arch/metag/include/asm/thread_info.h
index 4771133..91729f5 100644
--- a/arch/metag/include/asm/thread_info.h
+++ b/arch/metag/include/asm/thread_info.h
@@ -33,6 +33,7 @@ struct thread_info {
unsigned long status; /* thread-synchronous flags */
u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count; /* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
diff --git a/arch/microblaze/include/asm/thread_info.h b/arch/microblaze/include/asm/thread_info.h
index 8c9d365..f905b02 100644
--- a/arch/microblaze/include/asm/thread_info.h
+++ b/arch/microblaze/include/asm/thread_info.h
@@ -70,6 +70,7 @@ struct thread_info {
unsigned long status; /* thread-synchronous flags */
__u32 cpu; /* current CPU */
__s32 preempt_count; /* 0 => preemptable,< 0 => BUG*/
+ __s32 pagefault_count; /* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
diff --git a/arch/mips/include/asm/thread_info.h b/arch/mips/include/asm/thread_info.h
index 7de8658..f9f27ac 100644
--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -28,6 +28,7 @@ struct thread_info {
unsigned long tp_value; /* thread pointer */
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /*
* thread address space limit:
diff --git a/arch/mn10300/include/asm/thread_info.h b/arch/mn10300/include/asm/thread_info.h
index bf280ea..f6c03a5 100644
--- a/arch/mn10300/include/asm/thread_info.h
+++ b/arch/mn10300/include/asm/thread_info.h
@@ -45,6 +45,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
__u32 cpu; /* current CPU */
__s32 preempt_count; /* 0 => preemptable, <0 => BUG */
+ __s32 pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space:
0-0xBFFFFFFF for user-thead
diff --git a/arch/openrisc/include/asm/thread_info.h b/arch/openrisc/include/asm/thread_info.h
index d797acc..bdabd6e 100644
--- a/arch/openrisc/include/asm/thread_info.h
+++ b/arch/openrisc/include/asm/thread_info.h
@@ -52,6 +52,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
__u32 cpu; /* current CPU */
__s32 preempt_count; /* 0 => preemptable, <0 => BUG */
+ __s32 pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space:
0-0x7FFFFFFF for user-thead
diff --git a/arch/parisc/include/asm/thread_info.h b/arch/parisc/include/asm/thread_info.h
index a846118..e37b76b 100644
--- a/arch/parisc/include/asm/thread_info.h
+++ b/arch/parisc/include/asm/thread_info.h
@@ -14,6 +14,7 @@ struct thread_info {
mm_segment_t addr_limit; /* user-level address space limit */
__u32 cpu; /* current CPU */
int preempt_count; /* 0=premptable, <0=BUG; will also serve as bh-counter */
+ int pagefault_count; /* pagefault_disable() levels */
struct restart_block restart_block;
};
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index b034ecd..e8585fd 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -43,6 +43,7 @@ struct thread_info {
int cpu; /* cpu we're on */
int preempt_count; /* 0 => preemptable,
<0 => BUG */
+ int pagefault_count; /* pagefault_disable() levels */
struct restart_block restart_block;
unsigned long local_flags; /* private flags for thread */
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index 4d62fd5..bbf0513f 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -39,6 +39,7 @@ struct thread_info {
unsigned long sys_call_table; /* System call table address */
unsigned int cpu; /* current CPU */
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
struct restart_block restart_block;
unsigned int system_call;
__u64 user_timer;
diff --git a/arch/score/include/asm/thread_info.h b/arch/score/include/asm/thread_info.h
index 656b7ad..d7f748d 100644
--- a/arch/score/include/asm/thread_info.h
+++ b/arch/score/include/asm/thread_info.h
@@ -35,6 +35,7 @@ struct thread_info {
/* 0 => preemptable, < 0 => BUG */
int preempt_count;
+ int pagefault_count;/* pagefault_disable() levels */
/*
* thread address space:
diff --git a/arch/sh/include/asm/thread_info.h b/arch/sh/include/asm/thread_info.h
index ad27ffa..682a466 100644
--- a/arch/sh/include/asm/thread_info.h
+++ b/arch/sh/include/asm/thread_info.h
@@ -32,6 +32,7 @@ struct thread_info {
__u32 status; /* thread synchronous flags */
__u32 cpu;
int preempt_count; /* 0 => preemptable, <0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
unsigned long previous_sp; /* sp of previous stack in case
diff --git a/arch/sparc/include/asm/thread_info_32.h b/arch/sparc/include/asm/thread_info_32.h
index 025c984..ff0b112 100644
--- a/arch/sparc/include/asm/thread_info_32.h
+++ b/arch/sparc/include/asm/thread_info_32.h
@@ -49,6 +49,7 @@ struct thread_info {
unsigned long w_saved;
struct restart_block restart_block;
+ int pagefault_count;/* pagefault_disable() levels */
};
/*
diff --git a/arch/sparc/include/asm/thread_info_64.h b/arch/sparc/include/asm/thread_info_64.h
index 798f027..76a60ab 100644
--- a/arch/sparc/include/asm/thread_info_64.h
+++ b/arch/sparc/include/asm/thread_info_64.h
@@ -62,6 +62,7 @@ struct thread_info {
struct pt_regs *kern_una_regs;
unsigned int kern_una_insn;
+ int pagefault_count;/* pagefault_disable() levels */
unsigned long fpregs[(7 * 256) / sizeof(unsigned long)]
__attribute__ ((aligned(64)));
diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h
index 48e4fd0..57032b6 100644
--- a/arch/tile/include/asm/thread_info.h
+++ b/arch/tile/include/asm/thread_info.h
@@ -33,6 +33,7 @@ struct thread_info {
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable,
<0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space
(KERNEL_DS or USER_DS) */
diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
index 1c5b2a8..90b193c 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -19,6 +19,7 @@ struct thread_info {
__u32 cpu; /* current CPU */
int preempt_count; /* 0 => preemptable,
<0 => BUG */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* thread address space:
0-0xBFFFFFFF for user
0-0xFFFFFFFF for kernel */
diff --git a/arch/unicore32/include/asm/thread_info.h b/arch/unicore32/include/asm/thread_info.h
index af36d8e..1d50fb3 100644
--- a/arch/unicore32/include/asm/thread_info.h
+++ b/arch/unicore32/include/asm/thread_info.h
@@ -69,6 +69,7 @@ struct thread_info {
unsigned long flags; /* low level flags */
int preempt_count; /* 0 => preemptable */
/* <0 => bug */
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit; /* address limit */
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 547e344..fa075ab 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -30,6 +30,7 @@ struct thread_info {
__u32 status; /* thread synchronous flags */
__u32 cpu; /* current CPU */
int saved_preempt_count;
+ int pagefault_count;/* pagefault_disable() levels */
mm_segment_t addr_limit;
struct restart_block restart_block;
void __user *sysenter_return;
diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h
index 470153e..a866129 100644
--- a/arch/xtensa/include/asm/thread_info.h
+++ b/arch/xtensa/include/asm/thread_info.h
@@ -53,6 +53,7 @@ struct thread_info {
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
+ __s32 pagefault_count;/* pagefault_disable() levels */
unsigned long cpenable;
/* Allocate storage for extra user states and coprocessor states. */
--
1.8.5.5
next prev parent reply other threads:[~2014-12-10 14:23 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-10 14:23 [PATCH v2 0/5] Reenable might_sleep() checks for might_fault() David Hildenbrand
2014-12-10 14:23 ` David Hildenbrand
2014-12-10 14:23 ` David Hildenbrand [this message]
2014-12-10 14:23 ` [PATCH v2 1/5] uaccess: add pagefault_count to thread_info David Hildenbrand
2014-12-15 10:07 ` LF.Tan
2014-12-15 11:23 ` David Hildenbrand
2014-12-15 12:48 ` Peter Zijlstra
2014-12-10 14:23 ` [PATCH v2 2/5] uaccess: count pagefault_disable() levels in pagefault_count David Hildenbrand
2014-12-10 14:23 ` David Hildenbrand
2014-12-10 14:23 ` [PATCH v2 3/5] mm, uaccess: trigger might_sleep() in might_fault() when pagefaults are disabled David Hildenbrand
2014-12-10 14:23 ` [PATCH v2 4/5] uaccess: clarify that uaccess may only sleep if pagefaults are not disabled David Hildenbrand
2014-12-10 14:23 ` David Hildenbrand
2014-12-10 14:23 ` [PATCH v2 5/5] uaccess: CONFIG_DEBUG_PAGEFAULT_COUNT to debug pagefault_count David Hildenbrand
2014-12-10 14:23 ` David Hildenbrand
2014-12-15 10:45 ` [PATCH v2 0/5] Reenable might_sleep() checks for might_fault() Peter Zijlstra
2014-12-15 11:21 ` David Hildenbrand
2014-12-15 12:50 ` Peter Zijlstra
2014-12-15 13:08 ` David Hildenbrand
2015-01-12 14:19 ` David Hildenbrand
2015-01-30 15:52 ` Christian Borntraeger
2015-02-09 14:42 ` Peter Zijlstra
2015-02-19 14:48 ` David Hildenbrand
2015-02-19 15:07 ` Peter Zijlstra
2015-02-19 15:14 ` David Hildenbrand
2015-03-27 15:40 ` David Hildenbrand
2015-03-27 15:40 ` David Hildenbrand
2015-03-27 16:15 ` Peter Zijlstra
2015-03-27 19:05 ` David Hildenbrand
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