[PATCH 2/2] drm/i915: Update the breadcrumb interrupt counter before enabling

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



In order to close a race with a long running hangcheck comparing a stale
interrupt counter with a just started waiter, we need to first bump the
counter as we start the fresh wait.

References: https://bugs.freedesktop.org/show_bug.cgi?id=96974
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/i915/intel_breadcrumbs.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
index f0b56e3f4abe..d893ccdd62ac 100644
--- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
+++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
@@ -51,6 +51,13 @@ static void irq_enable(struct intel_engine_cs *engine)
 	 */
 	engine->breadcrumbs.irq_posted = true;
 
+	/* Make sure the current hangcheck doesn't falsely accuse a just
+	 * started irq handler from missing an interrupt (because the
+	 * interrupt count still matches the stale value from when
+	 * the irq handler was disabled, many hangchecks ago).
+	 */
+	engine->breadcrumbs.irq_wakeups++;
+
 	spin_lock_irq(&engine->i915->irq_lock);
 	engine->irq_enable(engine);
 	spin_unlock_irq(&engine->i915->irq_lock);
-- 
2.8.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux