Check that request has not been signaled before acquiring a reference to the request for signaling later in the interrupt handler.
The loading of the cacheline (for request->fence.flags) should be "free" when followed by the locked increment of the request->fence.refcount (which then sets the cacheline to exclusive mode), i.e. the cost of test_bit prior to an atomic_inc should be negligible. This should benefit us when we have a pile of bare breadcrumbs (interrupted execbuf) where we may get interrupts faster than we can get rid of the intel_wait, or if the device is too slow to run the bottom-half between interrupts. Signed-off-by: Chris Wilson <[email protected]> Cc: Mika Kuoppala <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Reviewed-by: Tvrtko Ursulin <[email protected]> --- drivers/gpu/drm/i915/i915_irq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 52e1fe8a98fb..736c7c4e7901 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -1056,7 +1056,9 @@ static void notify_ring(struct intel_engine_cs *engine) * and many waiters. */ if (i915_seqno_passed(intel_engine_get_seqno(engine), - wait->seqno)) + wait->seqno) && + !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, + &wait->request->fence.flags)) rq = i915_gem_request_get(wait->request); wake_up_process(wait->tsk); -- 2.11.0 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
