From eed7ec52f214bac2f25395ccaad610fbeb842a6e Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Sat, 24 Mar 2018 12:58:29 +0000 Subject: [PATCH] drm/i915/execlists: Clear user-active flag on preemption completion MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit When cancelling the requests and clearing out the ports following a successful preemption completion, also clear the active flag. I had assumed that all preemptions would be followed by an immediate dequeue (preserving the active user flag), but under rare circumstances we may be triggering a preemption for the second port only for it to have completed before the preemotion kicks in; leaving execlists->active set even though the system is now idle. We can clear the flag inside the common execlists_cancel_port_requests() as the other users also expect the semantics of active being cleared. Fixes: f6322eddaff7 ("drm/i915/preemption: Allow preemption between submission ports") Signed-off-by: Chris Wilson Cc: Michał Winiarski Cc: Michel Thierry Cc: Mika Kuoppala Cc: Tvrtko Ursulin Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20180324125829.27026-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/intel_lrc.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index b4ab06b05e58..9c84af53db94 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -577,6 +577,8 @@ static void execlists_dequeue(struct intel_engine_cs *engine) * know the next preemption status we see corresponds * to this ELSP update. */ + GEM_BUG_ON(!execlists_is_active(execlists, + EXECLISTS_ACTIVE_USER)); GEM_BUG_ON(!port_count(&port[0])); if (port_count(&port[0]) > 1) goto unlock; @@ -738,6 +740,8 @@ execlists_cancel_port_requests(struct intel_engine_execlists * const execlists) memset(port, 0, sizeof(*port)); port++; } + + execlists_clear_active(execlists, EXECLISTS_ACTIVE_USER); } static void clear_gtiir(struct intel_engine_cs *engine) @@ -1042,6 +1046,11 @@ static void execlists_submission_tasklet(unsigned long data) if (fw) intel_uncore_forcewake_put(dev_priv, execlists->fw_domains); + + /* If the engine is now idle, so should be the flag; and vice versa. */ + GEM_BUG_ON(execlists_is_active(&engine->execlists, + EXECLISTS_ACTIVE_USER) == + !port_isset(engine->execlists.port)); } static void queue_request(struct intel_engine_cs *engine, -- 2.30.2