Am 16.03.2017 um 10:00 schrieb Chunming Zhou:
> if high priority rq is full, then process with low priority could be starve.
> Add policy for this problem, the high proiority can ahead of next priority queue,
> the ratio is 2 : 1.
>
> Change-Id: I58f4a6b9cdce8689b18dd8e83dd6e2cf5f99d5fb
> Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
Well, the idea behind the high priority queues is to actually starve the
low priority queues to a certain amount.
At least for the kernel queue that is really desired.
Christian.
> ---
> drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 26 +++++++++++++++++++++++---
> drivers/gpu/drm/amd/scheduler/gpu_scheduler.h | 2 ++
> 2 files changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> index 0f439dd..4637b6f 100644
> --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> @@ -35,11 +35,16 @@
> static void amd_sched_process_job(struct fence *f, struct fence_cb *cb);
>
> /* Initialize a given run queue struct */
> -static void amd_sched_rq_init(struct amd_sched_rq *rq)
> +static void amd_sched_rq_init(struct amd_gpu_scheduler *sched, enum
> + amd_sched_priority pri)
> {
> + struct amd_sched_rq *rq = &sched->sched_rq[pri];
> +
> spin_lock_init(&rq->lock);
> INIT_LIST_HEAD(&rq->entities);
> rq->current_entity = NULL;
> + rq->wait_base = pri * 2;
> + rq->wait = rq->wait_base;
> }
>
> static void amd_sched_rq_add_entity(struct amd_sched_rq *rq,
> @@ -494,17 +499,32 @@ static void amd_sched_wakeup(struct amd_gpu_scheduler *sched)
> {
> struct amd_sched_entity *entity;
> int i;
> + bool skip;
>
> if (!amd_sched_ready(sched))
> return NULL;
>
> +retry:
> + skip = false;
> /* Kernel run queue has higher priority than normal run queue*/
> for (i = AMD_SCHED_PRIORITY_MAX - 1; i >= AMD_SCHED_PRIORITY_MIN; i--) {
> + if ((i > AMD_SCHED_PRIORITY_MIN) &&
> + (sched->sched_rq[i - 1].wait >= sched->sched_rq[i].wait_base)) {
> + sched->sched_rq[i - 1].wait = sched->sched_rq[i - 1].wait_base;
> + skip = true;
> + continue;
> + }
> entity = amd_sched_rq_select_entity(&sched->sched_rq[i]);
> - if (entity)
> + if (entity) {
> + if (i > AMD_SCHED_PRIORITY_MIN)
> + sched->sched_rq[i - 1].wait++;
> break;
> + }
> }
>
> + if (!entity && skip)
> + goto retry;
> +
> return entity;
> }
>
> @@ -608,7 +628,7 @@ int amd_sched_init(struct amd_gpu_scheduler *sched,
> sched->name = name;
> sched->timeout = timeout;
> for (i = AMD_SCHED_PRIORITY_MIN; i < AMD_SCHED_PRIORITY_MAX; i++)
> - amd_sched_rq_init(&sched->sched_rq[i]);
> + amd_sched_rq_init(sched, i);
>
> init_waitqueue_head(&sched->wake_up_worker);
> init_waitqueue_head(&sched->job_scheduled);
> diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
> index 99f0240..4caed30 100644
> --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
> +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.h
> @@ -64,6 +64,8 @@ struct amd_sched_rq {
> spinlock_t lock;
> struct list_head entities;
> struct amd_sched_entity *current_entity;
> + int wait_base;
> + int wait;
> };
>
> struct amd_sched_fence {
