From ceae14bd4cc4333b9a3b0b6b9457bb16e7ca410a Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 3 May 2017 10:39:20 +0100 Subject: [PATCH] drm/i915: Lift timeline ordering to await_dma_fence Currently we filter out repeated use of the same timeline in the low level i915_gem_request_await_request(), after having added the dependency on the old request. However, we can lift this to i915_gem_request_await_dma_fence() (before the dependency is added) using the observation that requests along the same timeline are explicitly ordered via i915_add_request (along with the dependencies). Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20170503093924.5320-3-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_request.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index b68935d056c5..022f5588d906 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -687,6 +687,7 @@ i915_gem_request_await_request(struct drm_i915_gem_request *to, int ret; GEM_BUG_ON(to == from); + GEM_BUG_ON(to->timeline == from->timeline); if (i915_gem_request_completed(from)) return 0; @@ -699,9 +700,6 @@ i915_gem_request_await_request(struct drm_i915_gem_request *to, return ret; } - if (to->timeline == from->timeline) - return 0; - if (to->engine == from->engine) { ret = i915_sw_fence_await_sw_fence_gfp(&to->submit, &from->submit, @@ -767,6 +765,14 @@ i915_gem_request_await_dma_fence(struct drm_i915_gem_request *req, if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) continue; + /* + * Requests on the same timeline are explicitly ordered, along + * with their dependencies, by i915_add_request() which ensures + * that requests are submitted in-order through each ring. + */ + if (fence->context == req->fence.context) + continue; + if (dma_fence_is_i915(fence)) ret = i915_gem_request_await_request(req, to_request(fence)); -- 2.20.1