From: Al Viro Date: Thu, 12 Jan 2006 09:05:34 +0000 (-0800) Subject: [PATCH] missing helper - task_stack_page() X-Git-Tag: v2.6.16-rc1~273 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9fc658763bf992e778243ebe898b03746151ab88;p=linux-2.6 [PATCH] missing helper - task_stack_page() Patchset annotates arch/* uses of ->thread_info. Ones that really are about access of thread_info of given process are simply switched to task_thread_info(task); ones that deal with access to objects on stack are switched to new helper - task_stack_page(). A _lot_ of the latter are actually open-coded instances of "find where pt_regs are"; those are consolidated into task_pt_regs(task) (many architectures actually have such helper already). Note that these annotations are not mandatory - any code not converted to these helpers still works. However, they clean up a lot of places and have actually caught a number of bugs, so converting out of tree ports would be a good idea... As an example of breakage caught by that stuff, see i386 pt_regs mess - we used to have it open-coded in a bunch of places and when back in April Stas had fixed a bug in copy_thread(), the rest had been left out of sync. That required two followup patches (the latest - just before 2.6.15) _and_ still had left /proc/*/stat eip field broken. Try ps -eo eip on i386 and watch the junk... This patch: new helper - task_stack_page(task). Returns pointer to the memory object containing task stack; usually thread_info of task sits in the beginning of that object. Signed-off-by: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/asm-m68k/thread_info.h b/include/asm-m68k/thread_info.h index 9532ca3c45..c4d622a57d 100644 --- a/include/asm-m68k/thread_info.h +++ b/include/asm-m68k/thread_info.h @@ -37,6 +37,7 @@ struct thread_info { #define init_stack (init_thread_union.stack) #define task_thread_info(tsk) (&(tsk)->thread.info) +#define task_stack_page(tsk) ((void *)(tsk)->thread_info) #define current_thread_info() task_thread_info(current) #define __HAVE_THREAD_FUNCTIONS diff --git a/include/linux/sched.h b/include/linux/sched.h index b5ef92a043..a72e171354 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1240,6 +1240,7 @@ static inline void task_unlock(struct task_struct *p) #ifndef __HAVE_THREAD_FUNCTIONS #define task_thread_info(task) (task)->thread_info +#define task_stack_page(task) ((void*)((task)->thread_info)) static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org) {