github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-24 15:12:13 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/i915/gt: Only retire on the last breadcrumb if the last request

Browse Source 
We use the completion of the last active breadcrumb to retire the
requests along a timeline. This is purely opportunistic as nothing
guarantees that any particular timeline is terminated by a breadcrumb;
except for parking the engine where we explicitly add a breadcrumb so
that we park quickly and do an explicit retire upon signaling to reduce
the latency dramatically (avoiding a retire worker roundtrip).

With scheduling, we anticipate retiring completed timelines as a matter
of course. Performing the same action from inside the breadcrumbs is
intended to provide similar functionality for legacy ringbuffer
submission.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210108204026.20682-5-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2021-01-08 20:40:24 +00:00
parent 2b2985a417
commit b1ad5f6d68
3 changed files with 13 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/gpu/drm/i915/gt/intel_breadcrumbs.c
View File

@ -257,17 +257,17 @@ static void signal_irq_work(struct irq_work *work)
list_del_rcu(&rq->signal_link);
release = remove_signaling_context(b, ce);
spin_unlock(&ce->signal_lock);
if (release) {
if (intel_timeline_is_last(ce->timeline, rq))
add_retire(b, ce->timeline);
intel_context_put(ce);
}
if (__dma_fence_signal(&rq->fence))
/* We own signal_node now, xfer to local list */
signal = slist_add(&rq->signal_node, signal);
else
i915_request_put(rq);
if (release) {
add_retire(b, ce->timeline);
intel_context_put(ce);
}
}
}
atomic_dec(&b->signaler_active);

2
drivers/gpu/drm/i915/gt/intel_execlists_submission.c
View File

@ -640,7 +640,7 @@ static inline void __execlists_schedule_out(struct i915_request *rq)
* If we have just completed this context, the engine may now be
* idle and we want to re-enter powersaving.
*/
if (list_is_last_rcu(&rq->link, &ce->timeline->requests) &&
if (intel_timeline_is_last(ce->timeline, rq) &&
__i915_request_is_complete(rq))
intel_engine_add_retire(engine, ce->timeline);

7
drivers/gpu/drm/i915/gt/intel_timeline.h
View File

@ -110,4 +110,11 @@ void intel_gt_show_timelines(struct intel_gt *gt,
const char *prefix,
int indent));
static inline bool
intel_timeline_is_last(const struct intel_timeline *tl,
const struct i915_request *rq)
{
return list_is_last_rcu(&rq->link, &tl->requests);
}
#endif