Power management fix for 3.11-rc6

- The removal of delayed_work_pending() checks from kernel/power/qos.c
   done in 3.9 introduced a deadlock in pm_qos_work_fn().  Fix from
   Stephen Boyd.
 
 /
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Merge tag 'pm-3.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fix from Rafael Wysocki:
 "The removal of delayed_work_pending() checks from kernel/power/qos.c
  done in 3.9 introduced a deadlock in pm_qos_work_fn().

  Fix from Stephen Boyd"

* tag 'pm-3.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / QoS: Fix workqueue deadlock when using pm_qos_update_request_timeout()
This commit is contained in:
Linus Torvalds 2013-08-16 09:59:00 -07:00
commit 2d2843e614
1 changed files with 13 additions and 7 deletions

View File

@ -296,6 +296,17 @@ int pm_qos_request_active(struct pm_qos_request *req)
}
EXPORT_SYMBOL_GPL(pm_qos_request_active);
static void __pm_qos_update_request(struct pm_qos_request *req,
s32 new_value)
{
trace_pm_qos_update_request(req->pm_qos_class, new_value);
if (new_value != req->node.prio)
pm_qos_update_target(
pm_qos_array[req->pm_qos_class]->constraints,
&req->node, PM_QOS_UPDATE_REQ, new_value);
}
/**
* pm_qos_work_fn - the timeout handler of pm_qos_update_request_timeout
* @work: work struct for the delayed work (timeout)
@ -308,7 +319,7 @@ static void pm_qos_work_fn(struct work_struct *work)
struct pm_qos_request,
work);
pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE);
__pm_qos_update_request(req, PM_QOS_DEFAULT_VALUE);
}
/**
@ -364,12 +375,7 @@ void pm_qos_update_request(struct pm_qos_request *req,
}
cancel_delayed_work_sync(&req->work);
trace_pm_qos_update_request(req->pm_qos_class, new_value);
if (new_value != req->node.prio)
pm_qos_update_target(
pm_qos_array[req->pm_qos_class]->constraints,
&req->node, PM_QOS_UPDATE_REQ, new_value);
__pm_qos_update_request(req, new_value);
}
EXPORT_SYMBOL_GPL(pm_qos_update_request);