| Message ID | 20191010071434.31195-1-chris@chris-wilson.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/10] drm/i915: Note the addition of timeslicing to the pretend scheduler | expand |
On 10/10/2019 08:14, Chris Wilson wrote: > Since writing the comment that the scheduler is entirely passive, we've > added minimal timeslicing which adds the most primitive of active > elements (a timeout and reschedule). > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> > Cc: Ramalingam C <ramalingam.c@intel.com> > --- > drivers/gpu/drm/i915/i915_scheduler_types.h | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_scheduler_types.h b/drivers/gpu/drm/i915/i915_scheduler_types.h > index aad81acba9dc..d18e70550054 100644 > --- a/drivers/gpu/drm/i915/i915_scheduler_types.h > +++ b/drivers/gpu/drm/i915/i915_scheduler_types.h > @@ -49,6 +49,15 @@ struct i915_sched_attr { > * DAG of each request, we are able to insert it into a sorted queue when it > * is ready, and are able to reorder its portion of the graph to accommodate > * dynamic priority changes. > + * > + * Ok, there is now one active element to the "scheduler" in the backends. > + * We let a new context run for a small amount of time before re-evaluating > + * the run order. As we re-evaluate, we maintain the strict ordering of > + * dependencies, but attempt to rotate the active contexts (the current context > + * is put to the back of its priority queue, then reshuffling its dependents). > + * This provides minimal timeslicing and prevents a userspace hog (e.g. > + * something waiting on a user semaphore [VkEvent]) from denying service to > + * others. > */ > struct i915_sched_node { > struct list_head signalers_list; /* those before us, we depend upon */ > Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Regards, Tvrtko
diff --git a/drivers/gpu/drm/i915/i915_scheduler_types.h b/drivers/gpu/drm/i915/i915_scheduler_types.h index aad81acba9dc..d18e70550054 100644 --- a/drivers/gpu/drm/i915/i915_scheduler_types.h +++ b/drivers/gpu/drm/i915/i915_scheduler_types.h @@ -49,6 +49,15 @@ struct i915_sched_attr { * DAG of each request, we are able to insert it into a sorted queue when it * is ready, and are able to reorder its portion of the graph to accommodate * dynamic priority changes. + * + * Ok, there is now one active element to the "scheduler" in the backends. + * We let a new context run for a small amount of time before re-evaluating + * the run order. As we re-evaluate, we maintain the strict ordering of + * dependencies, but attempt to rotate the active contexts (the current context + * is put to the back of its priority queue, then reshuffling its dependents). + * This provides minimal timeslicing and prevents a userspace hog (e.g. + * something waiting on a user semaphore [VkEvent]) from denying service to + * others. */ struct i915_sched_node { struct list_head signalers_list; /* those before us, we depend upon */
Since writing the comment that the scheduler is entirely passive, we've added minimal timeslicing which adds the most primitive of active elements (a timeout and reschedule). Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: Ramalingam C <ramalingam.c@intel.com> --- drivers/gpu/drm/i915/i915_scheduler_types.h | 9 +++++++++ 1 file changed, 9 insertions(+)