Commit c723e084 authored by Chuck Ebbert's avatar Chuck Ebbert Committed by Linus Torvalds

[PATCH] i386: use C code for current_thread_info()

Using C code for current_thread_info() lets the compiler optimize it.
With gcc 4.0.2, kernel is smaller:

    text           data     bss     dec     hex filename
 3645212         555556  312024 4512792  44dc18 2.6.17-rc6-nb-post/vmlinux
 3647276         555556  312024 4514856  44e428 2.6.17-rc6-nb/vmlinux
 -------
   -2064
Signed-off-by: default avatarChuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 4b89aff9
......@@ -83,17 +83,15 @@ struct thread_info {
#define init_stack (init_thread_union.stack)
/* how to get the current stack pointer from C */
register unsigned long current_stack_pointer asm("esp") __attribute_used__;
/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
struct thread_info *ti;
__asm__("andl %%esp,%0; ":"=r" (ti) : "0" (~(THREAD_SIZE - 1)));
return ti;
return (struct thread_info *)(current_stack_pointer & ~(THREAD_SIZE - 1));
}
/* how to get the current stack pointer from C */
register unsigned long current_stack_pointer asm("esp") __attribute_used__;
/* thread information allocation */
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(tsk) \
......
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