Commit b1becb88 authored Apr 03, 2017 by Chris Wilson

drm/i915: Park the signaler before sleeping



If the signal to park arrives before we sleep, then we need to check
kthread_should_park() before sleeping to avoid missing the signal.
Otherwise, if the signal arrives whilst we are processing completed
requests, we will reset the current->state back to TASK_INTERRUPTIBLE
and so miss the wakeup.

Fixes: fe3288b5 ("drm/i915: Park the breadcrumbs signaler across a GPU reset")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170403105124.8969-1-chris@chris-wilson.co.uk


Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

parent 7a3ee5de

drivers/gpu/drm/i915/intel_breadcrumbs.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -629,6 +629,9 @@ static int intel_breadcrumbs_signaler(void *arg)
		} else {
		DEFINE_WAIT(exec);

		if (kthread_should_park())
		kthread_parkme();

		if (kthread_should_stop()) {
		GEM_BUG_ON(request);
		break;
		@@ -641,9 +644,6 @@ static int intel_breadcrumbs_signaler(void *arg)

		if (request)
		remove_wait_queue(&request->execute, &exec);

		if (kthread_should_park())
		kthread_parkme();
		}
		i915_gem_request_put(request);
		} while (1);