From b6a6137c45d97b235028ce7e9c8bf2128830ae5b Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sat, 11 Jul 2020 10:13:49 +0100
Subject: drm/i915/gt: Always reset the engine, even if inactive, on execlists
Git-commit: 2730055dcb9a07f8aca27e6911defc29b41c71df
Patch-mainline: v5.9-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
failure
If something has gone awry with the CSB processing, we need to pause,
unwind and restart the request submission and event processing. However,
currently we skip the engine reset if we raise an error but discover no
active context, in the mistaken belief that it was merely a glitch in
the matrix. The glitches are real enough, and we do need to unwind even
if the engine appears idle (as it has gone permanently idle!) The
simplest way to unwind and recover is simply do the engine reset, which
should be very fast and _safe_ as nothing is active.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200711091349.28865-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gt/intel_lrc.c | 15 ++++++---------
1 file changed, 6 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index f27750acd916..24322ef08aa4 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -3029,12 +3029,12 @@ static u32 active_ccid(struct intel_engine_cs *engine)
return ENGINE_READ_FW(engine, RING_EXECLIST_STATUS_HI);
}
-static bool execlists_capture(struct intel_engine_cs *engine)
+static void execlists_capture(struct intel_engine_cs *engine)
{
struct execlists_capture *cap;
if (!IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR))
- return true;
+ return;
/*
* We need to _quickly_ capture the engine state before we reset.
@@ -3043,7 +3043,7 @@ static bool execlists_capture(struct intel_engine_cs *engine)
*/
cap = capture_regs(engine);
if (!cap)
- return true;
+ return;
spin_lock_irq(&engine->active.lock);
cap->rq = active_context(engine, active_ccid(engine));
@@ -3080,14 +3080,13 @@ static bool execlists_capture(struct intel_engine_cs *engine)
INIT_WORK(&cap->work, execlists_capture_work);
schedule_work(&cap->work);
- return true;
+ return;
err_rq:
i915_request_put(cap->rq);
err_free:
i915_gpu_coredump_put(cap->error);
kfree(cap);
- return false;
}
static void execlists_reset(struct intel_engine_cs *engine, const char *msg)
@@ -3107,10 +3106,8 @@ static void execlists_reset(struct intel_engine_cs *engine, const char *msg)
tasklet_disable_nosync(&engine->execlists.tasklet);
ring_set_paused(engine, 1); /* Freeze the current request in place */
- if (execlists_capture(engine))
- intel_engine_reset(engine, msg);
- else
- ring_set_paused(engine, 0);
+ execlists_capture(engine);
+ intel_engine_reset(engine, msg);
tasklet_enable(&engine->execlists.tasklet);
clear_and_wake_up_bit(bit, lock);
--
2.29.2