[Nouveau] [PATCH drm-misc-next 2/2] drm/nouveau: enable dynamic job flow control

[Danilo Krummrich]

Make use of the scheduler's submission limit and scheduler job's
submission unit count to account for the actual size of a job, such that
we fill up the ring efficiently.

Signed-off-by: Danilo Krummrich <dakr at redhat.com>
---
This patch is based on Matt's scheduler work [1] and [2].

[1] https://lore.kernel.org/dri-devel/20230919050155.2647172-1-matthew.brost@intel.com/
[2] https://lore.kernel.org/nouveau/20230924224555.15595-1-dakr@redhat.com/T/#u
---
 drivers/gpu/drm/nouveau/nouveau_abi16.c | 3 ++-
 drivers/gpu/drm/nouveau/nouveau_drm.c   | 2 +-
 drivers/gpu/drm/nouveau/nouveau_exec.c  | 3 ++-
 drivers/gpu/drm/nouveau/nouveau_sched.c | 9 ++++-----
 drivers/gpu/drm/nouveau/nouveau_sched.h | 3 ++-
 5 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_abi16.c b/drivers/gpu/drm/nouveau/nouveau_abi16.c
index f8e59cfb1d34..207945700c94 100644
--- a/drivers/gpu/drm/nouveau/nouveau_abi16.c
+++ b/drivers/gpu/drm/nouveau/nouveau_abi16.c
@@ -316,7 +316,8 @@ nouveau_abi16_ioctl_channel_alloc(ABI16_IOCTL_ARGS)
 	if (ret)
 		goto done;
 
-	ret = nouveau_sched_init(&chan->sched, drm, drm->sched_wq);
+	ret = nouveau_sched_init(&chan->sched, drm, drm->sched_wq,
+				 chan->chan->dma.ib_max);
 	if (ret)
 		goto done;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
index dbe1f08ac540..2b695c521821 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -317,7 +317,7 @@ nouveau_cli_init(struct nouveau_drm *drm, const char *sname,
 	 * locks which indirectly or directly are held for allocations
 	 * elsewhere.
 	 */
-	ret = nouveau_sched_init(&cli->sched, drm, NULL);
+	ret = nouveau_sched_init(&cli->sched, drm, NULL, 1);
 	if (ret)
 		goto done;
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_exec.c b/drivers/gpu/drm/nouveau/nouveau_exec.c
index 5a70fcf571f7..5d1533b413d3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_exec.c
+++ b/drivers/gpu/drm/nouveau/nouveau_exec.c
@@ -253,10 +253,11 @@ nouveau_exec_job_init(struct nouveau_exec_job **pjob,
 		}
 	}
 
+	args.file_priv = __args->file_priv;
 	job->chan = __args->chan;
 
 	args.sched = __args->sched;
-	args.file_priv = __args->file_priv;
+	args.submission_units = job->push.count;
 
 	args.in_sync.count = __args->in_sync.count;
 	args.in_sync.s = __args->in_sync.s;
diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c
index 0dbd0ea6d02e..6b32fd4eefb0 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sched.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sched.c
@@ -12,7 +12,6 @@
 #include "nouveau_abi16.h"
 #include "nouveau_sched.h"
 
-#define NOUVEAU_SCHED_HW_SUBMISSIONS		1
 #define NOUVEAU_SCHED_JOB_TIMEOUT_MS		10000
 
 int
@@ -77,10 +76,10 @@ nouveau_job_init(struct nouveau_job *job,
 			ret = -ENOMEM;
 			goto err_free_objs;
 		}
-
 	}
 
-	ret = drm_sched_job_init(&job->base, &sched->entity, 1, NULL);
+	ret = drm_sched_job_init(&job->base, &sched->entity,
+				 args->submission_units, NULL);
 	if (ret)
 		goto err_free_chains;
 
@@ -387,7 +386,7 @@ static const struct drm_sched_backend_ops nouveau_sched_ops = {
 };
 
 int nouveau_sched_init(struct nouveau_sched *sched, struct nouveau_drm *drm,
-		       struct workqueue_struct *wq)
+		       struct workqueue_struct *wq, u32 submission_limit)
 {
 	struct drm_gpu_scheduler *drm_sched = &sched->base;
 	struct drm_sched_entity *entity = &sched->entity;
@@ -404,7 +403,7 @@ int nouveau_sched_init(struct nouveau_sched *sched, struct nouveau_drm *drm,
 	}
 
 	ret = drm_sched_init(drm_sched, &nouveau_sched_ops, wq,
-			     NOUVEAU_SCHED_HW_SUBMISSIONS, 0, job_hang_limit,
+			     submission_limit, 0, job_hang_limit,
 			     NULL, NULL, "nouveau_sched",
 			     DRM_SCHED_POLICY_SINGLE_ENTITY, drm->dev->dev);
 	if (ret)
diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.h b/drivers/gpu/drm/nouveau/nouveau_sched.h
index 026f33d9b70c..c1d603759914 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sched.h
+++ b/drivers/gpu/drm/nouveau/nouveau_sched.h
@@ -27,6 +27,7 @@ enum nouveau_job_state {
 struct nouveau_job_args {
 	struct drm_file *file_priv;
 	struct nouveau_sched *sched;
+	u32 submission_units;
 
 	enum dma_resv_usage resv_usage;
 	bool sync;
@@ -112,7 +113,7 @@ struct nouveau_sched {
 };
 
 int nouveau_sched_init(struct nouveau_sched *sched, struct nouveau_drm *drm,
-		       struct workqueue_struct *wq);
+		       struct workqueue_struct *wq, u32 submission_limit);
 void nouveau_sched_fini(struct nouveau_sched *sched);
 
 #endif
-- 
2.41.0