[PATCH v2 23/23] drm/sched: Add (optional) fence signaling annotation

Rob Clark
2023-03-20T14:46:59Z

Based on
https://lore.kernel.org/dri-devel/20200604081224.863494-10-daniel.vetter@ffwll.ch/
but made to be optional.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
drivers/gpu/drm/msm/msm_ringbuffer.c | 1 +
drivers/gpu/drm/scheduler/sched_main.c | 9 +++++++++
include/drm/gpu_scheduler.h | 2 ++
3 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
index b60199184409..7e42baf16cd0 100644
--- a/drivers/gpu/drm/msm/msm_ringbuffer.c
+++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
@@ -93,6 +93,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int id,
/* currently managing hangcheck ourselves: */
sched_timeout = MAX_SCHEDULE_TIMEOUT;

+ ring->sched.fence_signaling = true;
ret = drm_sched_init(&ring->sched, &msm_sched_ops,
num_hw_submissions, 0, sched_timeout,
NULL, NULL, to_msm_bo(ring->bo)->name, gpu->dev->dev);
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 4e6ad6e122bc..c2ee44d6224b 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -978,10 +978,15 @@ static bool drm_sched_blocked(struct drm_gpu_scheduler *sched)
static int drm_sched_main(void *param)
{
struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param;
+ const bool fence_signaling = sched->fence_signaling;
+ bool fence_cookie;
int r;

sched_set_fifo_low(current);

+ if (fence_signaling)
+ fence_cookie = dma_fence_begin_signalling();
+
while (!kthread_should_stop()) {
struct drm_sched_entity *entity = NULL;
struct drm_sched_fence *s_fence;
@@ -1039,6 +1044,10 @@ static int drm_sched_main(void *param)

wake_up(&sched->job_scheduled);
}
+
+ if (fence_signaling)
+ dma_fence_end_signalling(fence_cookie);
+
return 0;
}

diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 9db9e5e504ee..8f23ea522e22 100644
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -483,6 +483,7 @@ struct drm_sched_backend_ops {
* @ready: marks if the underlying HW is ready to work
* @free_guilty: A hit to time out handler to free the guilty job.
* @dev: system &struct device
+ * @fence_signaling: Opt in to fence signaling annotations
*
* One scheduler is implemented for each hardware ring.
*/
@@ -507,6 +508,7 @@ struct drm_gpu_scheduler {
bool ready;
bool free_guilty;
struct device *dev;
+ bool fence_signaling;
};

int drm_sched_init(struct drm_gpu_scheduler *sched,
--
2.39.2