[RFC 4/4] drm/scheduler: Add fence deadline support

From: Rob Clark
Date: Mon Jul 26 2021 - 19:35:01 EST


From: Rob Clark <robdclark@xxxxxxxxxxxx>

As the finished fence is the one that is exposed to userspace, and
therefore the one that other operations, like atomic update, would
block on, we need to propagate the deadline from from the finished
fence to the actual hw fence.

Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
---
drivers/gpu/drm/scheduler/sched_fence.c | 10 ++++++++++
drivers/gpu/drm/scheduler/sched_main.c | 3 +++
2 files changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/scheduler/sched_fence.c b/drivers/gpu/drm/scheduler/sched_fence.c
index 69de2c76731f..3aa6351d2101 100644
--- a/drivers/gpu/drm/scheduler/sched_fence.c
+++ b/drivers/gpu/drm/scheduler/sched_fence.c
@@ -128,6 +128,15 @@ static void drm_sched_fence_release_finished(struct dma_fence *f)
dma_fence_put(&fence->scheduled);
}

+static void drm_sched_fence_set_deadline_finished(struct dma_fence *f,
+ ktime_t deadline)
+{
+ struct drm_sched_fence *fence = to_drm_sched_fence(f);
+
+ if (fence->parent)
+ dma_fence_set_deadline(fence->parent, deadline);
+}
+
static const struct dma_fence_ops drm_sched_fence_ops_scheduled = {
.get_driver_name = drm_sched_fence_get_driver_name,
.get_timeline_name = drm_sched_fence_get_timeline_name,
@@ -138,6 +147,7 @@ static const struct dma_fence_ops drm_sched_fence_ops_finished = {
.get_driver_name = drm_sched_fence_get_driver_name,
.get_timeline_name = drm_sched_fence_get_timeline_name,
.release = drm_sched_fence_release_finished,
+ .set_deadline = drm_sched_fence_set_deadline_finished,
};

struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f)
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index a2a953693b45..fcc601962e92 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -818,6 +818,9 @@ static int drm_sched_main(void *param)

if (!IS_ERR_OR_NULL(fence)) {
s_fence->parent = dma_fence_get(fence);
+ if (test_bit(DMA_FENCE_FLAG_HAS_DEADLINE_BIT,
+ &s_fence->finished.flags))
+ dma_fence_set_deadline(fence, s_fence->finished.deadline);
r = dma_fence_add_callback(fence, &sched_job->cb,
drm_sched_job_done_cb);
if (r == -ENOENT)
--
2.31.1