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| author | Tejun Heo <tj@kernel.org> | 2012-08-22 00:18:24 +0400 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2012-08-22 00:18:24 +0400 |
| commit | 57b30ae77bf00d2318df711ef9a4d2a9be0a3a2a (patch) | |
| tree | d6e084bf0e2b82bb39302ee0e94e6f3f04762dbc /include/linux/workqueue.h | |
| parent | e7c2f967445dd2041f0f8e3179cca22bb8bb7f79 (diff) | |
| download | linux-57b30ae77bf00d2318df711ef9a4d2a9be0a3a2a.tar.xz | |
workqueue: reimplement cancel_delayed_work() using try_to_grab_pending()
cancel_delayed_work() can't be called from IRQ handlers due to its use
of del_timer_sync() and can't cancel work items which are already
transferred from timer to worklist.
Also, unlike other flush and cancel functions, a canceled delayed_work
would still point to the last associated cpu_workqueue. If the
workqueue is destroyed afterwards and the work item is re-used on a
different workqueue, the queueing code can oops trying to dereference
already freed cpu_workqueue.
This patch reimplements cancel_delayed_work() using
try_to_grab_pending() and set_work_cpu_and_clear_pending(). This
allows the function to be called from IRQ handlers and makes its
behavior consistent with other flush / cancel functions.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'include/linux/workqueue.h')
| -rw-r--r-- | include/linux/workqueue.h | 17 |
1 files changed, 1 insertions, 16 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index d86b320319e0..4898289564ab 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -420,6 +420,7 @@ extern bool flush_work(struct work_struct *work); extern bool cancel_work_sync(struct work_struct *work); extern bool flush_delayed_work(struct delayed_work *dwork); +extern bool cancel_delayed_work(struct delayed_work *dwork); extern bool cancel_delayed_work_sync(struct delayed_work *dwork); extern void workqueue_set_max_active(struct workqueue_struct *wq, @@ -429,22 +430,6 @@ extern unsigned int work_cpu(struct work_struct *work); extern unsigned int work_busy(struct work_struct *work); /* - * Kill off a pending schedule_delayed_work(). Note that the work callback - * function may still be running on return from cancel_delayed_work(), unless - * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or - * cancel_work_sync() to wait on it. - */ -static inline bool cancel_delayed_work(struct delayed_work *work) -{ - bool ret; - - ret = del_timer_sync(&work->timer); - if (ret) - work_clear_pending(&work->work); - return ret; -} - -/* * Like above, but uses del_timer() instead of del_timer_sync(). This means, * if it returns 0 the timer function may be running and the queueing is in * progress. |