Unlike wake_up_process(), wake_up_q() doesn't tell us how many tasks have been woken up. This information can sometimes be useful for tracking purpose. So wake_up_q() is now modified to return that information. Signed-off-by: Waiman Long <longman@xxxxxxxxxx> --- include/linux/sched/wake_q.h | 2 +- kernel/futex.c | 8 +++----- kernel/sched/core.c | 6 ++++-- 3 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/linux/sched/wake_q.h b/include/linux/sched/wake_q.h index d03d8a9..8b88fc0 100644 --- a/include/linux/sched/wake_q.h +++ b/include/linux/sched/wake_q.h @@ -48,6 +48,6 @@ static inline void wake_q_init(struct wake_q_head *head) extern void wake_q_add(struct wake_q_head *head, struct task_struct *task); -extern void wake_up_q(struct wake_q_head *head); +extern int wake_up_q(struct wake_q_head *head); #endif /* _LINUX_SCHED_WAKE_Q_H */ diff --git a/kernel/futex.c b/kernel/futex.c index 984b836..a199574 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -4298,11 +4298,9 @@ static int futex_unlock(u32 __user *uaddr, unsigned int flags, out_put_key: put_futex_key(&key); if (owner) { - /* - * No error would have happened if owner defined. - */ - wake_up_q(&wake_q); - return ret ? ret : 1; + int cnt = wake_up_q(&wake_q); + + return ret ? ret : cnt; } return ret; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 6d6cad9..2193d59 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -447,9 +447,10 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task) head->lastp = &node->next; } -void wake_up_q(struct wake_q_head *head) +int wake_up_q(struct wake_q_head *head) { struct wake_q_node *node = head->first; + int wakecnt = 0; while (node != WAKE_Q_TAIL) { struct task_struct *task; @@ -464,9 +465,10 @@ void wake_up_q(struct wake_q_head *head) * wake_up_process() implies a wmb() to pair with the queueing * in wake_q_add() so as not to miss wakeups. */ - wake_up_process(task); + wakecnt += wake_up_process(task); put_task_struct(task); } + return wakecnt; } /* -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html