On 30/12/2024 16:52, Tvrtko Ursulin wrote:
From: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
Now that the scheduling policy is deadline based it feels completely
natural to allow propagating externaly set deadlines to the scheduler.
Scheduler deadlines are not a guarantee but as the dma-fence facility is
already in use by userspace lets wire it up.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@igalia.com>
Cc: Christian König <christian.koe...@amd.com>
Cc: Danilo Krummrich <d...@redhat.com>
Cc: Matthew Brost <matthew.br...@intel.com>
Cc: Philipp Stanner <pstan...@redhat.com>
Cc: Rob Clark <robdcl...@gmail.com>
---
drivers/gpu/drm/scheduler/sched_entity.c | 30 +++++++++++++++++++++++-
drivers/gpu/drm/scheduler/sched_fence.c | 3 +++
drivers/gpu/drm/scheduler/sched_rq.c | 16 +++++++++++++
include/drm/gpu_scheduler.h | 8 +++++++
4 files changed, 56 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/scheduler/sched_entity.c
b/drivers/gpu/drm/scheduler/sched_entity.c
index 14bc3f797079..c5a4c04b2455 100644
--- a/drivers/gpu/drm/scheduler/sched_entity.c
+++ b/drivers/gpu/drm/scheduler/sched_entity.c
@@ -385,7 +385,24 @@ ktime_t
drm_sched_entity_get_job_deadline(struct drm_sched_entity *entity,
struct drm_sched_job *job)
{
- return __drm_sched_entity_get_job_deadline(entity, job->submit_ts);
+ struct drm_sched_fence *s_fence = job->s_fence;
+ struct dma_fence *fence = &s_fence->finished;
+ ktime_t deadline;
+
+ deadline = __drm_sched_entity_get_job_deadline(entity, job->submit_ts);
+ if (test_bit(DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT, &fence->flags) &&
+ ktime_before(s_fence->deadline, deadline))
+ deadline = s_fence->deadline;
+
+ return deadline;
+}
+
+void drm_sched_entity_set_deadline(struct drm_sched_entity *entity,
+ ktime_t deadline)
+{
+ spin_lock(&entity->lock);
+ drm_sched_rq_update_deadline(entity->rq, entity, deadline);
+ spin_unlock(&entity->lock);
}
/*
@@ -536,8 +553,11 @@ void drm_sched_entity_select_rq(struct drm_sched_entity
*entity)
*/
void drm_sched_entity_push_job(struct drm_sched_job *sched_job)
{
+ struct drm_sched_fence *s_fence = sched_job->s_fence;
struct drm_sched_entity *entity = sched_job->entity;
+ struct dma_fence *fence = &s_fence->finished;
ktime_t submit_ts = ktime_get();
+ ktime_t fence_deadline;
bool first;
trace_drm_sched_job(sched_job, entity);
@@ -552,6 +572,11 @@ void drm_sched_entity_push_job(struct drm_sched_job
*sched_job)
* Make sure to set the submit_ts first, to avoid a race.
*/
sched_job->submit_ts = submit_ts;
+ if (test_bit(DRM_SCHED_FENCE_FLAG_HAS_DEADLINE_BIT, &fence->flags))
+ fence_deadline = s_fence->deadline;
+ else
+ fence_deadline = KTIME_MAX;
+
first = spsc_queue_push(&entity->job_queue, &sched_job->queue_node);
/* first job wakes up scheduler */
@@ -560,6 +585,9 @@ void drm_sched_entity_push_job(struct drm_sched_job
*sched_job)
submit_ts = __drm_sched_entity_get_job_deadline(entity,
submit_ts);
+ if (ktime_before(fence_deadline, submit_ts))
+ submit_ts = fence_deadline;
+
sched = drm_sched_rq_add_entity(entity->rq, entity, submit_ts);
if (sched)
drm_sched_wakeup(sched);
diff --git a/drivers/gpu/drm/scheduler/sched_fence.c
b/drivers/gpu/drm/scheduler/sched_fence.c
index 0f35f009b9d3..dfc7f50d4e0d 100644
--- a/drivers/gpu/drm/scheduler/sched_fence.c
+++ b/drivers/gpu/drm/scheduler/sched_fence.c
@@ -168,6 +168,8 @@ static void drm_sched_fence_set_deadline_finished(struct
dma_fence *f,
spin_unlock_irqrestore(&fence->lock, flags);
+ drm_sched_entity_set_deadline(fence->entity, deadline);
This I think needs re-work too becuase entities must not be acccessed
from jobs. Sigh. I can make it update the deadline inside the job itself
which will be applied when the job becomes first in the queue.
Regards,
Tvrtko
+
/*
* smp_load_aquire() to ensure that if we are racing another
* thread calling drm_sched_fence_set_parent(), that we see
@@ -223,6 +225,7 @@ void drm_sched_fence_init(struct drm_sched_fence *fence,
{
unsigned seq;
+ fence->entity = entity;
fence->sched = entity->rq->sched;
seq = atomic_inc_return(&entity->fence_seq);
dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled,
diff --git a/drivers/gpu/drm/scheduler/sched_rq.c
b/drivers/gpu/drm/scheduler/sched_rq.c
index 1a454384ab25..e96c8ca9c54b 100644
--- a/drivers/gpu/drm/scheduler/sched_rq.c
+++ b/drivers/gpu/drm/scheduler/sched_rq.c
@@ -148,6 +148,22 @@ void drm_sched_rq_pop_entity(struct drm_sched_rq *rq,
spin_unlock(&entity->lock);
}
+void drm_sched_rq_update_deadline(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity,
+ ktime_t deadline)
+{
+ lockdep_assert_held(&entity->lock);
+
+ if (ktime_before(deadline, entity->oldest_job_waiting)) {
+ spin_lock(&rq->lock);
+ if (!RB_EMPTY_NODE(&entity->rb_tree_node)) {
+ __drm_sched_rq_remove_tree_locked(entity, rq);
+ __drm_sched_rq_add_tree_locked(entity, rq, deadline);
+ }
+ spin_unlock(&rq->lock);
+ }
+}
+
/**
* drm_sched_rq_select_entity - Select an entity which provides a job to run
*
diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 85f3a0d5a7be..c68dce8af063 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -291,6 +291,9 @@ struct drm_sched_fence {
* &drm_sched_fence.finished fence once parent is signalled.
*/
struct dma_fence *parent;
+
+ struct drm_sched_entity *entity;
+
/**
* @sched: the scheduler instance to which the job having this struct
* belongs to.
@@ -597,6 +600,9 @@ void drm_sched_rq_pop_entity(struct drm_sched_rq *rq,
struct drm_sched_entity *
drm_sched_rq_select_entity(struct drm_gpu_scheduler *sched,
struct drm_sched_rq *rq);
+void drm_sched_rq_update_deadline(struct drm_sched_rq *rq,
+ struct drm_sched_entity *entity,
+ ktime_t deadline);
int drm_sched_entity_init(struct drm_sched_entity *entity,
enum drm_sched_priority priority,
@@ -612,6 +618,8 @@ void drm_sched_entity_push_job(struct drm_sched_job
*sched_job);
void drm_sched_entity_set_priority(struct drm_sched_entity *entity,
enum drm_sched_priority priority);
bool drm_sched_entity_is_ready(struct drm_sched_entity *entity);
+void drm_sched_entity_set_deadline(struct drm_sched_entity *entity,
+ ktime_t deadline);
int drm_sched_entity_error(struct drm_sched_entity *entity);
ktime_t drm_sched_entity_get_job_deadline(struct drm_sched_entity *entity,
struct drm_sched_job *job);
