From 29ef3fa987edb9768e19a6325030e1d2d58e29de Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 3 May 2017 10:39:19 +0100 Subject: [PATCH] drm/i915: Unwrap top level fence-array By first unwrapping an incoming fence-array into its child fences, we can simplify the internal branching, and so avoid triggering a potential bug in the next patch when not squashing the child fences on the same timeline. It will also have the advantage of keeping the (top-level) fence arrays out of any fence/timeline caching since these are unordered timelines but with a random context id. Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170503093924.5320-2-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_request.c | 41 +++++++++++-------------- 1 file changed, 18 insertions(+), 23 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index 6198f6997d05..b68935d056c5 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -743,22 +743,9 @@ int i915_gem_request_await_dma_fence(struct drm_i915_gem_request *req, struct dma_fence *fence) { - struct dma_fence_array *array; + struct dma_fence **child = &fence; + unsigned int nchild = 1; int ret; - int i; - - if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) - return 0; - - if (dma_fence_is_i915(fence)) - return i915_gem_request_await_request(req, to_request(fence)); - - if (!dma_fence_is_array(fence)) { - ret = i915_sw_fence_await_dma_fence(&req->submit, - fence, I915_FENCE_TIMEOUT, - GFP_KERNEL); - return ret < 0 ? ret : 0; - } /* Note that if the fence-array was created in signal-on-any mode, * we should *not* decompose it into its individual fences. However, @@ -767,21 +754,29 @@ i915_gem_request_await_dma_fence(struct drm_i915_gem_request *req, * amdgpu and we should not see any incoming fence-array from * sync-file being in signal-on-any mode. */ + if (dma_fence_is_array(fence)) { + struct dma_fence_array *array = to_dma_fence_array(fence); + + child = array->fences; + nchild = array->num_fences; + GEM_BUG_ON(!nchild); + } - array = to_dma_fence_array(fence); - for (i = 0; i < array->num_fences; i++) { - struct dma_fence *child = array->fences[i]; + do { + fence = *child++; + if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) + continue; - if (dma_fence_is_i915(child)) + if (dma_fence_is_i915(fence)) ret = i915_gem_request_await_request(req, - to_request(child)); + to_request(fence)); else - ret = i915_sw_fence_await_dma_fence(&req->submit, - child, I915_FENCE_TIMEOUT, + ret = i915_sw_fence_await_dma_fence(&req->submit, fence, + I915_FENCE_TIMEOUT, GFP_KERNEL); if (ret < 0) return ret; - } + } while (--nchild); return 0; } -- 2.20.1