From 618be8cc1ad1760103930b69ffbf528d7b861ab3 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 12 Jun 2017 15:17:20 +0100 Subject: i965: Resolve framebuffers before signaling the fence From KHR_fence_sync: When the condition of the sync object is satisfied by the fence command, the sync is signaled by the associated client API context, causing any eglClientWaitSyncKHR commands (see below) blocking on to unblock. The only condition currently supported is EGL_SYNC_PRIOR_COMMANDS_COMPLETE_KHR, which is satisfied by completion of the fence command corresponding to the sync object, and all preceding commands in the associated client API context's command stream. The sync object will not be signaled until all effects from these commands on the client API's internal and framebuffer state are fully realized. No other state is affected by execution of the fence command. If clients are passing the fence fd (from EGL_ANDROID_native_fence_sync) to a compositor, that fence must only be signaled once the framebuffer is resolved and not before as is currently the case. v2: fixup assert to use GL_SYNC_GPU_COMMANDS_COMPLETE (Chad) Reported-by: Sergi Granell Fixes: c636284ee8ee ("i965/sync: Implement DRI2_Fence extension") Signed-off-by: Chris Wilson Cc: Sergi Granell Cc: Rob Clark Cc: Chad Versace Cc: Daniel Stone Cc: Kenneth Graunke Reviewed-by: Chad Versace --- src/mesa/drivers/dri/i965/brw_sync.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) (limited to 'src') diff --git a/src/mesa/drivers/dri/i965/brw_sync.c b/src/mesa/drivers/dri/i965/brw_sync.c index a8356c304f9..edfb1881bc0 100644 --- a/src/mesa/drivers/dri/i965/brw_sync.c +++ b/src/mesa/drivers/dri/i965/brw_sync.c @@ -110,6 +110,35 @@ brw_fence_finish(struct brw_fence *fence) static bool MUST_CHECK brw_fence_insert_locked(struct brw_context *brw, struct brw_fence *fence) { + __DRIcontext *driContext = brw->driContext; + __DRIdrawable *driDrawable = driContext->driDrawablePriv; + + /* + * From KHR_fence_sync: + * + * When the condition of the sync object is satisfied by the fence + * command, the sync is signaled by the associated client API context, + * causing any eglClientWaitSyncKHR commands (see below) blocking on + * to unblock. The only condition currently supported is + * EGL_SYNC_PRIOR_COMMANDS_COMPLETE_KHR, which is satisfied by + * completion of the fence command corresponding to the sync object, + * and all preceding commands in the associated client API context's + * command stream. The sync object will not be signaled until all + * effects from these commands on the client API's internal and + * framebuffer state are fully realized. No other state is affected by + * execution of the fence command. + * + * Note the emphasis there on ensuring that the framebuffer is fully + * realised before the fence is signaled. We cannot just flush the batch, + * but must also resolve the drawable first. The importance of this is, + * for example, in creating a fence for a frame to be passed to a + * remote compositor. Without us flushing the drawable explicitly, the + * resolve will be in a following batch (when the client finally calls + * SwapBuffers, or triggers a resolve via some other path) and so the + * compositor may read the incomplete framebuffer instead. + */ + if (driDrawable) + intel_resolve_for_dri2_flush(brw, driDrawable); brw_emit_mi_flush(brw); switch (fence->type) { @@ -335,6 +364,9 @@ brw_gl_fence_sync(struct gl_context *ctx, struct gl_sync_object *_sync, struct brw_context *brw = brw_context(ctx); struct brw_gl_sync *sync = (struct brw_gl_sync *) _sync; + /* brw_fence_insert_locked() assumes it must do a complete flush */ + assert(condition == GL_SYNC_GPU_COMMANDS_COMPLETE); + brw_fence_init(brw, &sync->fence, BRW_FENCE_TYPE_BO_WAIT); if (!brw_fence_insert_locked(brw, &sync->fence)) { -- cgit v1.2.3