From fe49789fab974dd04c0fef26a4ce7f7f411b40dd Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 23 Feb 2017 07:44:13 +0000 Subject: [PATCH] drm/i915: Deconstruct execute fence On reflection, we are only using the execute fence as a waitqueue on the global_seqno and not using it for dependency tracking between fences (unlike the submit and dma fences). By only treating it as a waitqueue, we can then treat it similar to the other waitqueues during submit, making the code simpler. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170223074422.4125-8-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_request.c | 50 ++++++------------------- drivers/gpu/drm/i915/i915_gem_request.h | 10 +---- 2 files changed, 13 insertions(+), 47 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index 34d4c123546e..37ef7084fce5 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -69,7 +69,6 @@ static void i915_fence_release(struct dma_fence *fence) * caught trying to reuse dead objects. */ i915_sw_fence_fini(&req->submit); - i915_sw_fence_fini(&req->execute); kmem_cache_free(req->i915->requests, req); } @@ -294,7 +293,6 @@ static void i915_gem_request_retire(struct drm_i915_gem_request *request) lockdep_assert_held(&request->i915->drm.struct_mutex); GEM_BUG_ON(!i915_sw_fence_signaled(&request->submit)); - GEM_BUG_ON(!i915_sw_fence_signaled(&request->execute)); GEM_BUG_ON(!i915_gem_request_completed(request)); GEM_BUG_ON(!request->i915->gt.active_requests); @@ -402,6 +400,8 @@ void __i915_gem_request_submit(struct drm_i915_gem_request *request) struct intel_timeline *timeline; u32 seqno; + trace_i915_gem_request_execute(request); + /* Transfer from per-context onto the global per-engine timeline */ timeline = engine->timeline; GEM_BUG_ON(timeline == request->timeline); @@ -426,8 +426,7 @@ void __i915_gem_request_submit(struct drm_i915_gem_request *request) list_move_tail(&request->link, &timeline->requests); spin_unlock(&request->timeline->lock); - i915_sw_fence_commit(&request->execute); - trace_i915_gem_request_execute(request); + wake_up_all(&request->execute); } void i915_gem_request_submit(struct drm_i915_gem_request *request) @@ -463,24 +462,6 @@ submit_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state) return NOTIFY_DONE; } -static int __i915_sw_fence_call -execute_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state) -{ - struct drm_i915_gem_request *request = - container_of(fence, typeof(*request), execute); - - switch (state) { - case FENCE_COMPLETE: - break; - - case FENCE_FREE: - i915_gem_request_put(request); - break; - } - - return NOTIFY_DONE; -} - /** * i915_gem_request_alloc - allocate a request structure * @@ -573,13 +554,7 @@ i915_gem_request_alloc(struct intel_engine_cs *engine, /* We bump the ref for the fence chain */ i915_sw_fence_init(&i915_gem_request_get(req)->submit, submit_notify); - i915_sw_fence_init(&i915_gem_request_get(req)->execute, execute_notify); - - /* Ensure that the execute fence completes after the submit fence - - * as we complete the execute fence from within the submit fence - * callback, its completion would otherwise be visible first. - */ - i915_sw_fence_await_sw_fence(&req->execute, &req->submit, &req->execq); + init_waitqueue_head(&req->execute); i915_priotree_init(&req->priotree); @@ -1031,6 +1006,7 @@ long i915_wait_request(struct drm_i915_gem_request *req, TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE; wait_queue_head_t *errq = &req->i915->gpu_error.wait_queue; DEFINE_WAIT(reset); + DEFINE_WAIT(exec); struct intel_wait wait; might_sleep(); @@ -1052,12 +1028,11 @@ long i915_wait_request(struct drm_i915_gem_request *req, if (flags & I915_WAIT_LOCKED) add_wait_queue(errq, &reset); - if (!i915_sw_fence_done(&req->execute)) { - DEFINE_WAIT(exec); - + reset_wait_queue(&req->execute, &exec); + if (!req->global_seqno) { do { - prepare_to_wait(&req->execute.wait, &exec, state); - if (i915_sw_fence_done(&req->execute)) + set_current_state(state); + if (req->global_seqno) break; if (flags & I915_WAIT_LOCKED && @@ -1080,15 +1055,14 @@ long i915_wait_request(struct drm_i915_gem_request *req, timeout = io_schedule_timeout(timeout); } while (1); - finish_wait(&req->execute.wait, &exec); + finish_wait(&req->execute, &exec); if (timeout < 0) goto complete; - GEM_BUG_ON(!i915_sw_fence_done(&req->execute)); + GEM_BUG_ON(!req->global_seqno); } - GEM_BUG_ON(!i915_sw_fence_done(&req->submit)); - GEM_BUG_ON(!req->global_seqno); + GEM_BUG_ON(!i915_sw_fence_signaled(&req->submit)); /* Optimistic short spin before touching IRQs */ if (i915_spin_request(req, state, 5)) diff --git a/drivers/gpu/drm/i915/i915_gem_request.h b/drivers/gpu/drm/i915/i915_gem_request.h index 9049936c571c..467d3e13fce0 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.h +++ b/drivers/gpu/drm/i915/i915_gem_request.h @@ -119,18 +119,10 @@ struct drm_i915_gem_request { * The submit fence is used to await upon all of the request's * dependencies. When it is signaled, the request is ready to run. * It is used by the driver to then queue the request for execution. - * - * The execute fence is used to signal when the request has been - * sent to hardware. - * - * It is illegal for the submit fence of one request to wait upon the - * execute fence of an earlier request. It should be sufficient to - * wait upon the submit fence of the earlier request. */ struct i915_sw_fence submit; - struct i915_sw_fence execute; wait_queue_t submitq; - wait_queue_t execq; + wait_queue_head_t execute; /* A list of everyone we wait upon, and everyone who waits upon us. * Even though we will not be submitted to the hardware before the -- 2.45.2