Merge branch 'for-3.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull late workqueue fixes from Tejun Heo: "Unfortunately, I have two really late fixes. One was for a long-standing bug and queued for 3.8 but I found out about a regression introduced during 3.7-rc1 two days ago, so I'm sending out the two fixes together. The first (long-standing) one is rescuer_thread() entering exit path w/ TASK_INTERRUPTIBLE. It only triggers on workqueue destructions which isn't very frequent and the exit path can usually survive being called with TASK_INTERRUPT, so it was hidden pretty well. Apparently, if you're reiserfs, this could lead to the exiting kthread sleeping indefinitely holding a mutex, which is never good. The fix is simple - restoring TASK_RUNNING before returning from the kthread function. The second one is introduced by the new mod_delayed_work(). mod_delayed_work() was missing special case handling for 0 delay. Instead of queueing the work item immediately, it queued the timer which expires on the closest next tick. Some users of the new function converted from "[__]cancel_delayed_work() + queue_delayed_work()" combination became unhappy with the extra delay. Block unplugging led to noticeably higher number of context switches and intel 6250 wireless failed to associate with WPA-Enterprise network. The fix, again, is fairly simple. The 0 delay special case logic from queue_delayed_work_on() should be moved to __queue_delayed_work() which is shared by both queue_delayed_work_on() and mod_delayed_work_on(). The first one is difficult to trigger and the failure mode for the latter isn't completely catastrophic, so missing these two for 3.7 wouldn't make it a disastrous release, but both bugs are nasty and the fixes are fairly safe" * 'for-3.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: mod_delayed_work_on() shouldn't queue timer on 0 delay workqueue: exit rescuer_thread() as TASK_RUNNING
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