From d5370916d601b909c5cd69ff5a87619c04b8e30b Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 30 Mar 2020 13:16:44 +0100
Subject: drm/i915/selftests: Check timeout before flush and cond checks
Git-commit: 4b379a48ded0cb4d95471edfe91d55fe41f1d120
Patch-mainline: v5.8-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

Allow a bit of leniency for the CPU scheduler to be distracted while we
flush the tasklet and so ensure that we always check the status of the
request once more before timing out.

v2: Wait until the HW acked the submit, and we do any secondary actions
for the submit (e.g. timeslices)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200330121644.25277-1-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/gt/selftest_lrc.c | 33 +++++++++++++++++++-------
 1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c
index f95ae15ce865..86180fc5b493 100644
--- a/drivers/gpu/drm/i915/gt/selftest_lrc.c
+++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c
@@ -68,26 +68,41 @@ static void engine_heartbeat_enable(struct intel_engine_cs *engine,
 	engine->props.heartbeat_interval_ms = saved;
 }
 
+static bool is_active(struct i915_request *rq)
+{
+	if (i915_request_is_active(rq))
+		return true;
+
+	if (i915_request_on_hold(rq))
+		return true;
+
+	if (i915_request_started(rq))
+		return true;
+
+	return false;
+}
+
 static int wait_for_submit(struct intel_engine_cs *engine,
 			   struct i915_request *rq,
 			   unsigned long timeout)
 {
 	timeout += jiffies;
 	do {
-		cond_resched();
-		intel_engine_flush_submission(engine);
-
-		if (READ_ONCE(engine->execlists.pending[0]))
-			continue;
+		bool done = time_after(jiffies, timeout);
 
-		if (i915_request_is_active(rq))
+		if (i915_request_completed(rq)) /* that was quick! */
 			return 0;
 
-		if (i915_request_started(rq)) /* that was quick! */
+		/* Wait until the HW has acknowleged the submission (or err) */
+		intel_engine_flush_submission(engine);
+		if (!READ_ONCE(engine->execlists.pending[0]) && is_active(rq))
 			return 0;
-	} while (time_before(jiffies, timeout));
 
-	return -ETIME;
+		if (done)
+			return -ETIME;
+
+		cond_resched();
+	} while (1);
 }
 
 static int wait_for_reset(struct intel_engine_cs *engine,
-- 
2.28.0