If the scheduler rt thread gets stuck on a mutex that we're holding while waiting for gpu workloads to complete, we have a problem.
Add dma-fence annotations so that lockdep can check this for us.
I've tried to quite carefully review this, and I think it's at the right spot. But obviosly no expert on drm scheduler.
Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: linux-rdma@vger.kernel.org Cc: amd-gfx@lists.freedesktop.org Cc: intel-gfx@lists.freedesktop.org Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Christian König christian.koenig@amd.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com --- drivers/gpu/drm/scheduler/sched_main.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c index 2f319102ae9f..06a736e506ad 100644 --- a/drivers/gpu/drm/scheduler/sched_main.c +++ b/drivers/gpu/drm/scheduler/sched_main.c @@ -763,9 +763,12 @@ static int drm_sched_main(void *param) struct sched_param sparam = {.sched_priority = 1}; struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param; int r; + bool fence_cookie;
sched_setscheduler(current, SCHED_FIFO, &sparam);
+ fence_cookie = dma_fence_begin_signalling(); + while (!kthread_should_stop()) { struct drm_sched_entity *entity = NULL; struct drm_sched_fence *s_fence; @@ -823,6 +826,9 @@ static int drm_sched_main(void *param)
wake_up(&sched->job_scheduled); } + + dma_fence_end_signalling(fence_cookie); + return 0; }