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@intel.com Signed-off-by: Matthew Brost matthew.brost@intel.com
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);@@ -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);