diff options
| author | Dean Nelson <dcn@sgi.com> | 2004-06-20 04:54:29 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2004-06-20 04:54:29 -0700 |
| commit | a2816bbfb17101d2faa45c8b557da257a98fe729 (patch) | |
| tree | dc484c040d1c0d521a2795f0d15fb48256dacf4d | |
| parent | c87c2fe1694f4a6435eab283ac2c752a72e6dd2e (diff) | |
| download | history-a2816bbfb17101d2faa45c8b557da257a98fe729.tar.gz | |
[PATCH] add wait_event_interruptible_exclusive() macro
This patch defines a macro that does exactly what
wait_event_interruptible() does except that it adds the current task to the
wait queue as an exclusive task (i.e., sets the WQ_FLAG_EXCLUSIVE flag)
rather than as a non-exclusive task as wait_event_interruptible() does.
This allows one to do a wake_up_nr() to wake up a specific number of tasks.
I'm in the process of submitting a patch to linux-ia64 that requires this
capability. (Its subject line is "[PATCH 3/4] SGI Altix cross partition
functionality".)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | include/linux/wait.h | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index 52edb1786b14ac..4a9f996bb6ccea 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -200,7 +200,36 @@ do { \ __wait_event_interruptible_timeout(wq, condition, __ret); \ __ret; \ }) - + +#define __wait_event_interruptible_exclusive(wq, condition, ret) \ +do { \ + wait_queue_t __wait; \ + init_waitqueue_entry(&__wait, current); \ + \ + add_wait_queue_exclusive(&wq, &__wait); \ + for (;;) { \ + set_current_state(TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (!signal_pending(current)) { \ + schedule(); \ + continue; \ + } \ + ret = -ERESTARTSYS; \ + break; \ + } \ + current->state = TASK_RUNNING; \ + remove_wait_queue(&wq, &__wait); \ +} while (0) + +#define wait_event_interruptible_exclusive(wq, condition) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __wait_event_interruptible_exclusive(wq, condition, __ret);\ + __ret; \ +}) + /* * Must be called with the spinlock in the wait_queue_head_t held. */ |