From 2d453c7895c0ca6028500050ff9305c70fd7252f Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 22 Dec 2017 14:19:59 +0000 Subject: [PATCH] drm/i915: Assert that the request is on the execution queue before being removed MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We should only attempt to remove requests from the execution queue that are on the execution queue. These are the requests that have been assigned a global_seqno, so we can assert that we only attempt to remove requests with a nonzero global_seqno. Afterwards we assert that we remove them in order, i.e. the global_seqno matches the engine's seqno, but that leaves a small loophole for an unattached request on an unused engine. We can then make the same assertion on queuing the request to the execution engine, it must have a zero global_seqno or else we are queuing the same request twice. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Cc: Michał Winiarski Link: https://patchwork.freedesktop.org/patch/msgid/20171222141959.3006-1-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_gem_request.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index 59f023bb7015..d575109f7a7f 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -479,6 +479,7 @@ void __i915_gem_request_submit(struct drm_i915_gem_request *request) /* Transfer from per-context onto the global per-engine timeline */ timeline = engine->timeline; GEM_BUG_ON(timeline == request->timeline); + GEM_BUG_ON(request->global_seqno); seqno = timeline_get_seqno(timeline); GEM_BUG_ON(!seqno); @@ -525,6 +526,7 @@ void __i915_gem_request_unsubmit(struct drm_i915_gem_request *request) /* Only unwind in reverse order, required so that the per-context list * is kept in seqno/ring order. */ + GEM_BUG_ON(!request->global_seqno); GEM_BUG_ON(request->global_seqno != engine->timeline->seqno); engine->timeline->seqno--;