Commit aa34a6fc authored Nov 24, 2017 by Chris Wilson

drm/i915/guc: Advance over port[0] if set and not preempting



Our execlist emulation is intended to only use a maximum of 2 ports per
engine, so as to not overflow the wq. (By knowing the limits, we can
avoid having to handle the wq exhaustion.) However, upon adding
preemption, we lost the skip over the first port if set for the
non-preemption path. Restore it.

Reported-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Fixes: c41937fd ("drm/i915/guc: Preemption! With GuC")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171124133745.5173-1-chris@chris-wilson.co.uk


Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>

parent bb9e0d4b

drivers/gpu/drm/i915/intel_guc_submission.c

+16 −13

Original line number	Diff line number	Diff line
		@@ -743,7 +743,8 @@ static void guc_dequeue(struct intel_engine_cs *engine)
		if (!rb)
		goto unlock;

		if (HAS_LOGICAL_RING_PREEMPTION(engine->i915) && port_isset(port)) {
		if (port_isset(port)) {
		if (HAS_LOGICAL_RING_PREEMPTION(engine->i915)) {
		struct guc_preempt_work *preempt_work =
		&engine->i915->guc.preempt_work[engine->id];

		@@ -754,12 +755,14 @@ static void guc_dequeue(struct intel_engine_cs *engine)
		queue_work(engine->i915->guc.preempt_wq,
		&preempt_work->work);
		goto unlock;
		} else if (port_isset(last_port)) {
		goto unlock;
		}
		}

		port++;
		if (port_isset(port))
		goto unlock;
		}
		GEM_BUG_ON(port_isset(port));

		do {
		struct i915_priolist p = rb_entry(rb, typeof(p), node);