[PATCH 1/2] sched: INIT_PREEMPT_COUNT

From: Peter Zijlstra
Date: Fri Jul 10 2009 - 09:04:53 EST

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Pull the initial preempt_count value into a single
definition site.

Maintainers for: alpha, ia64 and m68k, please have a look,
your arch code is funny.

The header magic is a bit odd, but similar to the KERNEL_DS
one, CPP waits with expanding these macros until the
INIT_THREAD_INFO macro itself is expanded, which is in
arch/*/kernel/init_task.c where we've already included
sched.h so we're good.

Cc: tony.luck@xxxxxxxxx
Cc: rth@xxxxxxxxxxx
Cc: geert@xxxxxxxxxxxxxx
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
arch/alpha/include/asm/thread_info.h | 1 +
arch/arm/include/asm/thread_info.h | 2 +-
arch/avr32/include/asm/thread_info.h | 2 +-
arch/blackfin/include/asm/thread_info.h | 2 +-
arch/cris/include/asm/thread_info.h | 4 +---
arch/frv/include/asm/thread_info.h | 4 +---
arch/h8300/include/asm/thread_info.h | 2 +-
arch/ia64/include/asm/thread_info.h | 2 +-
arch/m32r/include/asm/thread_info.h | 4 +---
arch/m68k/include/asm/thread_info_mm.h | 1 +
arch/m68k/include/asm/thread_info_no.h | 1 +
arch/microblaze/include/asm/thread_info.h | 4 +---
arch/mips/include/asm/thread_info.h | 4 +---
arch/mn10300/include/asm/thread_info.h | 4 +---
arch/parisc/include/asm/thread_info.h | 2 +-
arch/powerpc/include/asm/thread_info.h | 4 +---
arch/s390/include/asm/thread_info.h | 2 +-
arch/sh/include/asm/thread_info.h | 2 +-
arch/sparc/include/asm/thread_info_32.h | 4 +---
arch/sparc/include/asm/thread_info_64.h | 4 +---
arch/um/include/asm/thread_info.h | 2 +-
arch/x86/include/asm/thread_info.h | 2 +-
arch/xtensa/include/asm/thread_info.h | 4 +---
include/linux/sched.h | 6 ++++++
24 files changed, 29 insertions(+), 40 deletions(-)

Index: linux-2.6/arch/alpha/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/alpha/include/asm/thread_info.h
+++ linux-2.6/arch/alpha/include/asm/thread_info.h
@@ -37,6 +37,7 @@ struct thread_info {
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.addr_limit = KERNEL_DS, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/arm/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/arm/include/asm/thread_info.h
+++ linux-2.6/arch/arm/include/asm/thread_info.h
@@ -73,7 +73,7 @@ struct thread_info {
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.flags = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.cpu_domain = domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
Index: linux-2.6/arch/avr32/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/avr32/include/asm/thread_info.h
+++ linux-2.6/arch/avr32/include/asm/thread_info.h
@@ -40,7 +40,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall \
} \
Index: linux-2.6/arch/blackfin/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/blackfin/include/asm/thread_info.h
+++ linux-2.6/arch/blackfin/include/asm/thread_info.h
@@ -77,7 +77,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/cris/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/cris/include/asm/thread_info.h
+++ linux-2.6/arch/cris/include/asm/thread_info.h
@@ -50,8 +50,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__
#define INIT_THREAD_INFO(tsk) \
@@ -60,7 +58,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/frv/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/frv/include/asm/thread_info.h
+++ linux-2.6/arch/frv/include/asm/thread_info.h
@@ -56,8 +56,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__

@@ -67,7 +65,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/h8300/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/h8300/include/asm/thread_info.h
+++ linux-2.6/arch/h8300/include/asm/thread_info.h
@@ -36,7 +36,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/ia64/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/ia64/include/asm/thread_info.h
+++ linux-2.6/arch/ia64/include/asm/thread_info.h
@@ -48,7 +48,7 @@ struct thread_info {
.flags = 0, \
.cpu = 0, \
.addr_limit = KERNEL_DS, \
- .preempt_count = 0, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/m32r/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/m32r/include/asm/thread_info.h
+++ linux-2.6/arch/m32r/include/asm/thread_info.h
@@ -57,8 +57,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__

@@ -68,7 +66,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/m68k/include/asm/thread_info_mm.h
===================================================================
--- linux-2.6.orig/arch/m68k/include/asm/thread_info_mm.h
+++ linux-2.6/arch/m68k/include/asm/thread_info_mm.h
@@ -19,6 +19,7 @@ struct thread_info {
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/m68k/include/asm/thread_info_no.h
===================================================================
--- linux-2.6.orig/arch/m68k/include/asm/thread_info_no.h
+++ linux-2.6/arch/m68k/include/asm/thread_info_no.h
@@ -49,6 +49,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/microblaze/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/microblaze/include/asm/thread_info.h
+++ linux-2.6/arch/microblaze/include/asm/thread_info.h
@@ -75,8 +75,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#define INIT_THREAD_INFO(tsk) \
{ \
@@ -84,7 +82,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/mips/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/mips/include/asm/thread_info.h
+++ linux-2.6/arch/mips/include/asm/thread_info.h
@@ -39,8 +39,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#define INIT_THREAD_INFO(tsk) \
{ \
@@ -48,7 +46,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = _TIF_FIXADE, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/mn10300/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/mn10300/include/asm/thread_info.h
+++ linux-2.6/arch/mn10300/include/asm/thread_info.h
@@ -65,8 +65,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__

@@ -76,7 +74,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/parisc/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/parisc/include/asm/thread_info.h
+++ linux-2.6/arch/parisc/include/asm/thread_info.h
@@ -23,7 +23,7 @@ struct thread_info {
.flags = 0, \
.cpu = 0, \
.addr_limit = KERNEL_DS, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall \
} \
Index: linux-2.6/arch/powerpc/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/powerpc/include/asm/thread_info.h
+++ linux-2.6/arch/powerpc/include/asm/thread_info.h
@@ -46,15 +46,13 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#define INIT_THREAD_INFO(tsk) \
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/s390/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/s390/include/asm/thread_info.h
+++ linux-2.6/arch/s390/include/asm/thread_info.h
@@ -61,7 +61,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/sh/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/sh/include/asm/thread_info.h
+++ linux-2.6/arch/sh/include/asm/thread_info.h
@@ -51,7 +51,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/sparc/include/asm/thread_info_32.h
===================================================================
--- linux-2.6.orig/arch/sparc/include/asm/thread_info_32.h
+++ linux-2.6/arch/sparc/include/asm/thread_info_32.h
@@ -54,8 +54,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#define INIT_THREAD_INFO(tsk) \
{ \
@@ -64,7 +62,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/sparc/include/asm/thread_info_64.h
===================================================================
--- linux-2.6.orig/arch/sparc/include/asm/thread_info_64.h
+++ linux-2.6/arch/sparc/include/asm/thread_info_64.h
@@ -125,8 +125,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/
#ifndef __ASSEMBLY__

@@ -135,7 +133,7 @@ struct thread_info {
.task = &tsk, \
.flags = ((unsigned long)ASI_P) << TI_FLAG_CURRENT_DS_SHIFT, \
.exec_domain = &default_exec_domain, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
Index: linux-2.6/arch/um/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/um/include/asm/thread_info.h
+++ linux-2.6/arch/um/include/asm/thread_info.h
@@ -32,7 +32,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/x86/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/thread_info.h
+++ linux-2.6/arch/x86/include/asm/thread_info.h
@@ -49,7 +49,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/arch/xtensa/include/asm/thread_info.h
===================================================================
--- linux-2.6.orig/arch/xtensa/include/asm/thread_info.h
+++ linux-2.6/arch/xtensa/include/asm/thread_info.h
@@ -80,8 +80,6 @@ struct thread_info {

/*
* macros/functions for gaining access to the thread information structure
- *
- * preempt_count needs to be 1 initially, until the scheduler is functional.
*/

#ifndef __ASSEMBLY__
@@ -92,7 +90,7 @@ struct thread_info {
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
- .preempt_count = 1, \
+ .preempt_count = INIT_PREEMPT_COUNT, \
.addr_limit = KERNEL_DS, \
.restart_block = { \
.fn = do_no_restart_syscall, \
Index: linux-2.6/include/linux/sched.h
===================================================================
--- linux-2.6.orig/include/linux/sched.h
+++ linux-2.6/include/linux/sched.h
@@ -500,6 +500,12 @@ struct task_cputime {
.sum_exec_runtime = 0, \
}

+/*
+ * Disable preemption until the scheduler is running.
+ * Reset by start_kernel()->sched_init()->init_idle().
+ */
+#define INIT_PREEMPT_COUNT (1)
+
/**
* struct thread_group_cputimer - thread group interval timer counts
* @cputime: thread group interval timers.

--

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Next message: Thomas Gleixner: "Re: Intel BIOS - Corrupted low memory at ffff880000004200"
Previous message: Peter Zijlstra: "[PATCH 0/2] cond_resched() optimization"
In reply to: Matt Mackall: "Re: [PATCH 2/2] sched: optimize cond_resched()"
Next in thread: Valdis . Kletnieks: "Re: [PATCH 1/2] sched: INIT_PREEMPT_COUNT"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]