From: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
encapsulates the rest of arch-dependent operations with thread_info access.
Two new helpers - setup_thread_stack() and end_of_stack(). For normal case
the former consists of copying thread_info of parent to new thread_info and
the latter returns pointer immediately past the end of thread_info.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
include/linux/sched.h | 11 +++++++++++
kernel/fork.c | 3 +--
kernel/sched.c | 4 ++--
3 files changed, 14 insertions(+), 4 deletions(-)
diff -puN include/linux/sched.h~m68k-introduce-setup_thread_stack-end_of_stack include/linux/sched.h
--- devel/include/linux/sched.h~m68k-introduce-setup_thread_stack-end_of_stack 2005-09-07 20:11:04.000000000 -0700
+++ devel-akpm/include/linux/sched.h 2005-09-07 20:11:04.000000000 -0700
@@ -1184,6 +1184,17 @@ static inline void task_unlock(struct ta
#define task_thread_info(task) (task)->thread_info
+static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
+{
+ *task_thread_info(p) = *task_thread_info(org);
+ task_thread_info(p)->task = p;
+}
+
+static inline unsigned long *end_of_stack(struct task_struct *p)
+{
+ return (unsigned long *)(p->thread_info + 1);
+}
+
/* set thread flags in other task's structures
* - see asm/thread_info.h for TIF_xxxx flags available
*/
diff -puN kernel/fork.c~m68k-introduce-setup_thread_stack-end_of_stack kernel/fork.c
--- devel/kernel/fork.c~m68k-introduce-setup_thread_stack-end_of_stack 2005-09-07 20:11:04.000000000 -0700
+++ devel-akpm/kernel/fork.c 2005-09-07 20:11:04.000000000 -0700
@@ -169,10 +169,9 @@ static struct task_struct *dup_task_stru
return NULL;
}
- *ti = *orig->thread_info;
*tsk = *orig;
tsk->thread_info = ti;
- ti->task = tsk;
+ setup_thread_stack(tsk, orig);
/* One for us, one for whoever does the "release_task()" (usually parent) */
atomic_set(&tsk->usage,2);
diff -puN kernel/sched.c~m68k-introduce-setup_thread_stack-end_of_stack kernel/sched.c
--- devel/kernel/sched.c~m68k-introduce-setup_thread_stack-end_of_stack 2005-09-07 20:11:04.000000000 -0700
+++ devel-akpm/kernel/sched.c 2005-09-07 20:11:04.000000000 -0700
@@ -4336,10 +4336,10 @@ static void show_task(task_t *p)
#endif
#ifdef CONFIG_DEBUG_STACK_USAGE
{
- unsigned long *n = (unsigned long *) (p->thread_info+1);
+ unsigned long *n = end_of_stack(p);
while (!*n)
n++;
- free = (unsigned long) n - (unsigned long)(p->thread_info+1);
+ free = (unsigned long)n - (unsigned long)end_of_stack(p);
}
#endif
printk("%5lu %5d %6d ", free, p->pid, p->parent->pid);
_