<div dir="ltr"> <div class="gmail_quote"><div dir="ltr">On Thu, Aug 2, 2018 at 11:29 AM Zhang, Jerry (Junwei) <<a href="mailto:Jerry.Zhang@amd.com">Jerry.Zhang@amd.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On 08/02/2018 01:50 PM, Nayan Deshmukh wrote: > > > On Thu, Aug 2, 2018 at 10:31 AM Zhang, Jerry (Junwei) <<a href="mailto:Jerry.Zhang@amd.com" target="_blank">Jerry.Zhang@amd.com</a> <mailto:<a href="mailto:Jerry.Zhang@amd.com" target="_blank">Jerry.Zhang@amd.com</a>>> wrote: > > On 07/12/2018 02:36 PM, Nayan Deshmukh wrote: > > Signed-off-by: Nayan Deshmukh <<a href="mailto:nayan26deshmukh@gmail.com" target="_blank">nayan26deshmukh@gmail.com</a> <mailto:<a href="mailto:nayan26deshmukh@gmail.com" target="_blank">nayan26deshmukh@gmail.com</a>>> > > --- > > drivers/gpu/drm/scheduler/gpu_scheduler.c | 3 +++ > > include/drm/gpu_scheduler.h | 2 ++ > > 2 files changed, 5 insertions(+) > > > > diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler.c b/drivers/gpu/drm/scheduler/gpu_scheduler.c > > index 429b1328653a..3dc1a4f07e3f 100644 > > --- a/drivers/gpu/drm/scheduler/gpu_scheduler.c > > +++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c > > @@ -538,6 +538,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job, > > trace_drm_sched_job(sched_job, entity); > > > > first = spsc_queue_push(&entity->job_queue, &sched_job->queue_node); > > + atomic_inc(&entity->sched->num_jobs); > > Shall we use hw_rq_count directly or merge them together? > > hw_rq_count is the number of jobs that are currently in the hardware queue as compared to num_jobs which is the number of jobs in the software queue. num_jobs provides a give a better idea of the load > on a scheduler that's why I added that field and used it to decide the scheduler with the least load. Thanks for your explanation. Then may be more reasonable to move atomic_dec(&sched->num_jobs) after drm_sched_fence_scheduled() or just before atomic_inc(&sched->hw_rq_count). How do you think that? </blockquote><div>For now num_jobs also includes jobs that have been pushed to the hardware queue. If I shift it before atomic_inc(&sched->hw_rq_count) then I also need to handle cases when the job was reset and update the counter properly. I went for the easier implementation as I felt that num_jobs will correctly represent the load on the scheduler. </div><div>But the idea that you suggested can be a potential improvement over what I have done. </div><div>Regards, </div><div>Nayan </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Regards, Jerry > > Regards, > Nayan > > > Regards, > Jerry > > > > /* first job wakes up scheduler */ > > if (first) { > > @@ -818,6 +819,7 @@ static void drm_sched_process_job(struct dma_fence *f, struct dma_fence_cb *cb) > > > > dma_fence_get(&s_fence->finished); > > atomic_dec(&sched->hw_rq_count); > > + atomic_dec(&sched->num_jobs); > > drm_sched_fence_finished(s_fence); > > > > trace_drm_sched_process_job(s_fence); > > @@ -935,6 +937,7 @@ int drm_sched_init(struct drm_gpu_scheduler *sched, > > INIT_LIST_HEAD(&sched->ring_mirror_list); > > spin_lock_init(&sched->job_list_lock); > > atomic_set(&sched->hw_rq_count, 0); > > + atomic_set(&sched->num_jobs, 0); > > atomic64_set(&sched->job_id_count, 0); > > > > /* Each scheduler will run on a seperate kernel thread */ > > diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h > > index 43e93d6077cf..605bd4ad2397 100644 > > --- a/include/drm/gpu_scheduler.h > > +++ b/include/drm/gpu_scheduler.h > > @@ -257,6 +257,7 @@ struct drm_sched_backend_ops { > > * @job_list_lock: lock to protect the ring_mirror_list. > > * @hang_limit: once the hangs by a job crosses this limit then it is marked > > * guilty and it will be considered for scheduling further. > > + * @num_jobs: the number of jobs in queue in the scheduler > > * > > * One scheduler is implemented for each hardware ring. > > */ > > @@ -274,6 +275,7 @@ struct drm_gpu_scheduler { > > struct list_head ring_mirror_list; > > spinlock_t job_list_lock; > > int hang_limit; > > + atomic_t num_jobs; > > }; > > > > int drm_sched_init(struct drm_gpu_scheduler *sched, > > > </blockquote></div></div>