From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sat, 24 Mar 2018 12:58:29 +0000
Subject: drm/i915/execlists: Clear user-active flag on preemption completion
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Git-commit: 38057aa1639b74d5c1e0dc1ca7c22bc7a31de714
Patch-mainline: v4.17-rc2
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
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 <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180324125829.27026-1-chris@chris-wilson.co.uk
(cherry picked from commit eed7ec52f214bac2f25395ccaad610fbeb842a6e)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/i915/intel_lrc.c | 9 +++++++++
1 file changed, 9 insertions(+)
--- 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 int
* 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 in
memset(port, 0, sizeof(*port));
port++;
}
+
+ execlists_clear_active(execlists, EXECLISTS_ACTIVE_USER);
}
static void execlists_cancel_requests(struct intel_engine_cs *engine)
@@ -1001,6 +1005,11 @@ static void execlists_submission_tasklet
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,