diff options
| author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2008-07-23 21:26:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-24 10:47:14 -0700 |
| commit | 8b05c7e6e159d2f33c9275281b8b909a89eb7c5d (patch) | |
| tree | 646edb14c42d6404e36f1602d47c639c72a8300a | |
| parent | 68ad8df42e12037c3894c9706ab428bf5cd6426b (diff) | |
add a helper function to test if an object is on the stack
lib/debugobjects.c has a function to test if an object is on the stack.
The block layer and ide needs it (they need to avoid DMA from/to stack
buffers). This patch moves the function to include/linux/sched.h so that
everyone can use it.
lib/debugobjects.c uses current->stack but this patch uses a
task_stack_page() accessor, which is a preferable way to access the stack.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/sched.h | 7 | ||||
| -rw-r--r-- | lib/debugobjects.c | 4 |
2 files changed, 8 insertions, 3 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index dc7e592c473..6aca4a16e37 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1983,6 +1983,13 @@ static inline unsigned long *end_of_stack(struct task_struct *p) #endif +static inline int object_is_on_stack(void *obj) +{ + void *stack = task_stack_page(current); + + return (obj >= stack) && (obj < (stack + THREAD_SIZE)); +} + extern void thread_info_cache_init(void); /* set thread flags in other task's structures diff --git a/lib/debugobjects.c b/lib/debugobjects.c index 85b18d79be8..f86196390cf 100644 --- a/lib/debugobjects.c +++ b/lib/debugobjects.c @@ -226,15 +226,13 @@ debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state), static void debug_object_is_on_stack(void *addr, int onstack) { - void *stack = current->stack; int is_on_stack; static int limit; if (limit > 4) return; - is_on_stack = (addr >= stack && addr < (stack + THREAD_SIZE)); - + is_on_stack = object_is_on_stack(addr); if (is_on_stack == onstack) return; |