diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 18:03:02 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 18:03:02 +0200 |
commit | fa5312d9e87e7222c6c384c4e930dc149bc1178d (patch) | |
tree | 3a181e52c7ae863de566a6b30248a175742a8406 /kernel | |
parent | Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/... (diff) | |
parent | workqueue: change cancel_work_sync() to clear work->data (diff) | |
download | linux-fa5312d9e87e7222c6c384c4e930dc149bc1178d.tar.xz linux-fa5312d9e87e7222c6c384c4e930dc149bc1178d.zip |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: change cancel_work_sync() to clear work->data
workqueue: warn about flush_scheduled_work()
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/workqueue.c | 36 |
1 files changed, 35 insertions, 1 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 5bfb213984b2..77dabbf64b8f 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -229,6 +229,16 @@ static inline void set_wq_data(struct work_struct *work, atomic_long_set(&work->data, new); } +/* + * Clear WORK_STRUCT_PENDING and the workqueue on which it was queued. + */ +static inline void clear_wq_data(struct work_struct *work) +{ + unsigned long flags = *work_data_bits(work) & + (1UL << WORK_STRUCT_STATIC); + atomic_long_set(&work->data, flags); +} + static inline struct cpu_workqueue_struct *get_wq_data(struct work_struct *work) { @@ -671,7 +681,7 @@ static int __cancel_work_timer(struct work_struct *work, wait_on_work(work); } while (unlikely(ret < 0)); - work_clear_pending(work); + clear_wq_data(work); return ret; } @@ -845,6 +855,30 @@ int schedule_on_each_cpu(work_func_t func) return 0; } +/** + * flush_scheduled_work - ensure that any scheduled work has run to completion. + * + * Forces execution of the kernel-global workqueue and blocks until its + * completion. + * + * Think twice before calling this function! It's very easy to get into + * trouble if you don't take great care. Either of the following situations + * will lead to deadlock: + * + * One of the work items currently on the workqueue needs to acquire + * a lock held by your code or its caller. + * + * Your code is running in the context of a work routine. + * + * They will be detected by lockdep when they occur, but the first might not + * occur very often. It depends on what work items are on the workqueue and + * what locks they need, which you have no control over. + * + * In most situations flushing the entire workqueue is overkill; you merely + * need to know that a particular work item isn't queued and isn't running. + * In such cases you should use cancel_delayed_work_sync() or + * cancel_work_sync() instead. + */ void flush_scheduled_work(void) { flush_workqueue(keventd_wq); |