Chris Wilson <[email protected]> writes: > Since we are system_highpri_wq, we expected the heartbeat to be > scheduled promptly. However, we see delays of over 10ms upsetting our > assertions. Accept this as inevitable and bump the minimum error > threshold to 20ms (from 6 jiffies). > > <6> [616.784749] rcs0: Heartbeat delay: 3570us [2802, 9188] > <6> [616.807790] bcs0: Heartbeat delay: 2111us [745, 4372] > <6> [616.853776] vcs0: Heartbeat delay: 6485us [2424, 11637] > <3> [616.859296] vcs0: Heartbeat delay was 6485us, expected less than 6000us > <3> [616.860901] i915/intel_heartbeat_live_selftests: live_heartbeat_fast > failed with error -22 > > v2: More context from CI. > > Signed-off-by: Chris Wilson <[email protected]> > Cc: Mika Kuoppala <[email protected]>
Reviewed-by: Mika Kuoppala <[email protected]> > --- > drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c | 13 ++++++++++--- > 1 file changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > index b88aa35ad75b..223ab88f7e57 100644 > --- a/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > +++ b/drivers/gpu/drm/i915/gt/selftest_engine_heartbeat.c > @@ -197,6 +197,7 @@ static int cmp_u32(const void *_a, const void *_b) > > static int __live_heartbeat_fast(struct intel_engine_cs *engine) > { > + const unsigned int error_threshold = max(20000u, jiffies_to_usecs(6)); > struct intel_context *ce; > struct i915_request *rq; > ktime_t t0, t1; > @@ -254,12 +255,18 @@ static int __live_heartbeat_fast(struct intel_engine_cs > *engine) > times[0], > times[ARRAY_SIZE(times) - 1]); > > - /* Min work delay is 2 * 2 (worst), +1 for scheduling, +1 for slack */ > - if (times[ARRAY_SIZE(times) / 2] > jiffies_to_usecs(6)) { > + /* > + * Ideally, the upper bound on min work delay would be something like > + * 2 * 2 (worst), +1 for scheduling, +1 for slack. In practice, we > + * are, even with system_wq_highpri, at the mercy of the CPU scheduler > + * and may be stuck behind some slow work for many millisecond. Such > + * as our very own display workers. > + */ > + if (times[ARRAY_SIZE(times) / 2] > error_threshold) { > pr_err("%s: Heartbeat delay was %uus, expected less than > %dus\n", > engine->name, > times[ARRAY_SIZE(times) / 2], > - jiffies_to_usecs(6)); > + error_threshold); > err = -EINVAL; > } > > -- > 2.20.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
