On 25/05/2021 18:01, Matthew Brost wrote:
On Tue, May 25, 2021 at 10:52:01AM +0100, Tvrtko Ursulin wrote:
On 06/05/2021 20:14, Matthew Brost wrote:
Disable semaphores when using GuC scheduling as semaphores are broken in
the current GuC firmware.
What is "current"? Given that the patch itself is like year and a half old.
Stale comment. Semaphore work with the firmware we just haven't enabled
them in the i915 with GuC submission as this an optimization and not
required for functionality.
How will the updated commit message look in terms of remaining reasons
why semaphores won't/can't be enabled?
They were a nice performance win on some media workloads although
granted a lot of tweaking was required to find a good balance on when to
use them and when not to.
Regards,
Tvrtko
Matt
Regards,
Tvrtko
Cc: John Harrison <john.c.harrison@xxxxxxxxx>
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
drivers/gpu/drm/i915/gem/i915_gem_context.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 993faa213b41..d30260ffe2a7 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -230,7 +230,8 @@ static void intel_context_set_gem(struct intel_context *ce,
ce->timeline = intel_timeline_get(ctx->timeline);
if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
- intel_engine_has_timeslices(ce->engine))
+ intel_engine_has_timeslices(ce->engine) &&
+ intel_engine_has_semaphores(ce->engine))
__set_bit(CONTEXT_USE_SEMAPHORES, &ce->flags);
intel_context_set_watchdog_us(ce, ctx->watchdog.timeout_us);
@@ -1939,7 +1940,8 @@ static int __apply_priority(struct intel_context *ce, void *arg)
if (!intel_engine_has_timeslices(ce->engine))
return 0;
- if (ctx->sched.priority >= I915_PRIORITY_NORMAL)
+ if (ctx->sched.priority >= I915_PRIORITY_NORMAL &&
+ intel_engine_has_semaphores(ce->engine))
intel_context_set_use_semaphores(ce);
else
intel_context_clear_use_semaphores(ce);
