The partial initialization of wait_queue_t in prepare_to_wait_event() looks ugly. This was done to shrink .text, but we can simply add the new helper which does the full initialization and shrink the compiled code a bit more.
And. This way prepare_to_wait_event() can have more users. In particular we are ready to remove the signal_pending_state() checks from wait_bit_action_f helpers and change __wait_on_bit_lock() to use prepare_to_wait_event(). Signed-off-by: Oleg Nesterov <[email protected]> --- include/linux/wait.h | 9 +++------ kernel/sched/wait.c | 12 +++++++++--- 2 files changed, 12 insertions(+), 9 deletions(-) diff --git a/include/linux/wait.h b/include/linux/wait.h index 52953a5..1b8a930 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -248,6 +248,8 @@ wait_queue_head_t *bit_waitqueue(void *, int); (!__builtin_constant_p(state) || \ state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ +extern void init_wait_entry(wait_queue_t *__wait, int flags); + /* * The below macro ___wait_event() has an explicit shadow of the __ret * variable when used from the wait_event_*() macros. @@ -266,12 +268,7 @@ wait_queue_head_t *bit_waitqueue(void *, int); wait_queue_t __wait; \ long __ret = ret; /* explicit shadow */ \ \ - INIT_LIST_HEAD(&__wait.task_list); \ - if (exclusive) \ - __wait.flags = WQ_FLAG_EXCLUSIVE; \ - else \ - __wait.flags = 0; \ - \ + init_wait_entry(&__wait, exclusive ? WQ_FLAG_EXCLUSIVE : 0); \ for (;;) { \ long __int = prepare_to_wait_event(&wq, &__wait, state);\ \ diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c index 47c4d62..61dcee1 100644 --- a/kernel/sched/wait.c +++ b/kernel/sched/wait.c @@ -196,14 +196,20 @@ prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state) } EXPORT_SYMBOL(prepare_to_wait_exclusive); +void init_wait_entry(wait_queue_t *wait, int flags) +{ + wait->flags = flags; + wait->private = current; + wait->func = autoremove_wake_function; + INIT_LIST_HEAD(&wait->task_list); +} +EXPORT_SYMBOL(init_wait_entry); + long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state) { unsigned long flags; long ret = 0; - wait->private = current; - wait->func = autoremove_wake_function; - spin_lock_irqsave(&q->lock, flags); if (unlikely(signal_pending_state(state, current))) { /* -- 2.5.0
