sigtimedwait: use freezable blocking call

Avoid waking up every thread sleeping in a sigtimedwait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Colin Cross 2013-05-06 23:50:20 +00:00 committed by Rafael J. Wysocki
parent b0f8c44f30
commit a2d5f1f5d9

View file

@ -2848,7 +2848,7 @@ int do_sigtimedwait(const sigset_t *which, siginfo_t *info,
recalc_sigpending();
spin_unlock_irq(&tsk->sighand->siglock);
timeout = schedule_timeout_interruptible(timeout);
timeout = freezable_schedule_timeout_interruptible(timeout);
spin_lock_irq(&tsk->sighand->siglock);
__set_task_blocked(tsk, &tsk->real_blocked);