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    Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq · 033d9959
    Linus Torvalds authored
    Pull workqueue changes from Tejun Heo:
     "This is workqueue updates for v3.7-rc1.  A lot of activities this
      round including considerable API and behavior cleanups.
    
       * delayed_work combines a timer and a work item.  The handling of the
         timer part has always been a bit clunky leading to confusing
         cancelation API with weird corner-case behaviors.  delayed_work is
         updated to use new IRQ safe timer and cancelation now works as
         expected.
    
       * Another deficiency of delayed_work was lack of the counterpart of
         mod_timer() which led to cancel+queue combinations or open-coded
         timer+work usages.  mod_delayed_work[_on]() are added.
    
         These two delayed_work changes make delayed_work provide interface
         and behave like timer which is executed with process context.
    
       * A work item could be executed concurrently on multiple CPUs, which
         is rather unintuitive and made flush_work() behavior confusing and
         half-broken under certain circumstances.  This problem doesn't
         exist for non-reentrant workqueues.  While non-reentrancy check
         isn't free, the overhead is incurred only when a work item bounces
         across different CPUs and even in simulated pathological scenario
         the overhead isn't too high.
    
         All workqueues are made non-reentrant.  This removes the
         distinction between flush_[delayed_]work() and
         flush_[delayed_]_work_sync().  The former is now as strong as the
         latter and the specified work item is guaranteed to have finished
         execution of any previous queueing on return.
    
       * In addition to the various bug fixes, Lai redid and simplified CPU
         hotplug handling significantly.
    
       * Joonsoo introduced system_highpri_wq and used it during CPU
         hotplug.
    
      There are two merge commits - one to pull in IRQ safe timer from
      tip/timers/core and the other to pull in CPU hotplug fixes from
      wq/for-3.6-fixes as Lai's hotplug restructuring depended on them."
    
    Fixed a number of trivial conflicts, but the more interesting conflicts
    were silent ones where the deprecated interfaces had been used by new
    code in the merge window, and thus didn't cause any real data conflicts.
    
    Tejun pointed out a few of them, I fixed a couple more.
    
    * 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (46 commits)
      workqueue: remove spurious WARN_ON_ONCE(in_irq()) from try_to_grab_pending()
      workqueue: use cwq_set_max_active() helper for workqueue_set_max_active()
      workqueue: introduce cwq_set_max_active() helper for thaw_workqueues()
      workqueue: remove @delayed from cwq_dec_nr_in_flight()
      workqueue: fix possible stall on try_to_grab_pending() of a delayed work item
      workqueue: use hotcpu_notifier() for workqueue_cpu_down_callback()
      workqueue: use __cpuinit instead of __devinit for cpu callbacks
      workqueue: rename manager_mutex to assoc_mutex
      workqueue: WORKER_REBIND is no longer necessary for idle rebinding
      workqueue: WORKER_REBIND is no longer necessary for busy rebinding
      workqueue: reimplement idle worker rebinding
      workqueue: deprecate __cancel_delayed_work()
      workqueue: reimplement cancel_delayed_work() using try_to_grab_pending()
      workqueue: use mod_delayed_work() instead of __cancel + queue
      workqueue: use irqsafe timer for delayed_work
      workqueue: clean up delayed_work initializers and add missing one
      workqueue: make deferrable delayed_work initializer names consistent
      workqueue: cosmetic whitespace updates for macro definitions
      workqueue: deprecate system_nrt[_freezable]_wq
      workqueue: deprecate flush[_delayed]_work_sync()
      ...
    033d9959