From 7c9e934ef8a09a1a42f15ce9f0f872fdfdb67b97 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 24 Jan 2017 11:00:09 +0000 Subject: [PATCH] drm/i915: Emit dma-fence (and execlists submit) first from signaler When introduced, I thought that reducing client latency from the signaler was the priority. Since its inception the signaler has become responsible for keeping the execlists full, via the dma-fence. As this is very important to minimise overall execution time, signal the dma-fence first and then signal any waiting clients. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170124110009.28947-8-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_breadcrumbs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c index 6b24f2544b6b..9fd002bcebb6 100644 --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c @@ -459,16 +459,16 @@ static int intel_breadcrumbs_signaler(void *arg) */ request = READ_ONCE(b->first_signal); if (signal_complete(request)) { + local_bh_disable(); + dma_fence_signal(&request->fence); + local_bh_enable(); /* kick start the tasklets */ + /* Wake up all other completed waiters and select the * next bottom-half for the next user interrupt. */ intel_engine_remove_wait(engine, &request->signaling.wait); - local_bh_disable(); - dma_fence_signal(&request->fence); - local_bh_enable(); /* kick start the tasklets */ - /* Find the next oldest signal. Note that as we have * not been holding the lock, another client may * have installed an even older signal than the one -- 2.20.1