From 90a79a91dcc0e8b1986a2ad9b00cf3b281fb09f0 Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Wed, 24 Mar 2021 12:13:32 +0000 Subject: [PATCH] drm/i915: Handle async cancellation in sentinel assert With the watchdog cancelling requests asynchronously to preempt-to-busy we need to relax one assert making it apply only to requests not in error. v2: * Check against the correct request! v3: * Simplify the check to avoid the question of when to sample the fence error vs sentinel bit. Signed-off-by: Tvrtko Ursulin Reviewed-by: Matthew Auld Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210324121335.2307063-5-tvrtko.ursulin@linux.intel.com --- drivers/gpu/drm/i915/gt/intel_execlists_submission.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c index eacc7371a4b9..2578e8cce930 100644 --- a/drivers/gpu/drm/i915/gt/intel_execlists_submission.c +++ b/drivers/gpu/drm/i915/gt/intel_execlists_submission.c @@ -757,9 +757,8 @@ assert_pending_valid(const struct intel_engine_execlists *execlists, { struct intel_engine_cs *engine = container_of(execlists, typeof(*engine), execlists); - struct i915_request * const *port, *rq; + struct i915_request * const *port, *rq, *prev = NULL; struct intel_context *ce = NULL; - bool sentinel = false; u32 ccid = -1; trace_ports(execlists, msg, execlists->pending); @@ -809,15 +808,20 @@ assert_pending_valid(const struct intel_engine_execlists *execlists, * Sentinels are supposed to be the last request so they flush * the current execution off the HW. Check that they are the only * request in the pending submission. + * + * NB: Due to the async nature of preempt-to-busy and request + * cancellation we need to handle the case where request + * becomes a sentinel in parallel to CSB processing. */ - if (sentinel) { + if (prev && i915_request_has_sentinel(prev) && + !READ_ONCE(prev->fence.error)) { GEM_TRACE_ERR("%s: context:%llx after sentinel in pending[%zd]\n", engine->name, ce->timeline->fence_context, port - execlists->pending); return false; } - sentinel = i915_request_has_sentinel(rq); + prev = rq; /* * We want virtual requests to only be in the first slot so -- 2.20.1