[PATCH 4/6] drm/i915/execlists: Make submission tasklet hardirq safe

[Chris Wilson]

Prepare to allow the execlists submission to be run from underneath a
hardirq timer context (and not just the current softirq context) as is
required for fast preemption resets.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_lrc.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 02789194f33f..fbe0a7ec8522 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -757,15 +757,16 @@ static bool __execlists_dequeue(struct intel_engine_cs *engine)
 static void execlists_dequeue(struct intel_engine_cs *engine)
 {
 	struct intel_engine_execlists * const execlists = &engine->execlists;
+	unsigned long uninitialized_var(flags);
 	bool submit;
 
 	if (!intel_engine_direct_submit(engine))
-		spin_lock_irq(&engine->timeline.lock);
+		spin_lock_irqsave(&engine->timeline.lock, flags);
 
 	submit = __execlists_dequeue(engine);
 
 	if (!intel_engine_direct_submit(engine))
-		spin_unlock_irq(&engine->timeline.lock);
+		spin_unlock_irqrestore(&engine->timeline.lock, flags);
 
 	if (submit)
 		execlists_submit_ports(engine);
-- 
2.17.0