drm/scheduler: only kill entity if last user is killed v2

Note which task is using the entity and only kill it if the last user of
the entity is killed. This should prevent problems when entities are leaked to
child processes.

v2: add missing kernel doc

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: Nayan Deshmukh <nayan26deshmukh@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler.c b/drivers/gpu/drm/scheduler/gpu_scheduler.c
index 3f2fc5e8242ab1e9d039a4d2ce0294652eb846cc..f563e4fbb4b68ca71b11d930e682448555107f34 100644 (file)
--- a/drivers/gpu/drm/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c
@@ -275,6 +275,7 @@ static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
 long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
 {
        struct drm_gpu_scheduler *sched;
+       struct task_struct *last_user;
        long ret = timeout;
 
        sched = entity->rq->sched;
@@ -295,7 +296,9 @@ long drm_sched_entity_flush(struct drm_sched_entity *entity, long timeout)
 
 
        /* For killed process disable any more IBs enqueue right now */
-       if ((current->flags & PF_EXITING) && (current->exit_code == SIGKILL))
+       last_user = cmpxchg(&entity->last_user, current->group_leader, NULL);
+       if ((!last_user || last_user == current->group_leader) &&
+           (current->flags & PF_EXITING) && (current->exit_code == SIGKILL))
                drm_sched_entity_set_rq(entity, NULL);
 
        return ret;
@@ -541,6 +544,7 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
 
        trace_drm_sched_job(sched_job, entity);
 
+       WRITE_ONCE(entity->last_user, current->group_leader);
        first = spsc_queue_push(&entity->job_queue, &sched_job->queue_node);
 
        /* first job wakes up scheduler */

diff --git a/include/drm/gpu_scheduler.h b/include/drm/gpu_scheduler.h
index 091b9afcd184c8281dc529581e0c69f3d5149d85..21c648b0b2a16c6dce65d61a75ced0823999ed95 100644 (file)
--- a/include/drm/gpu_scheduler.h
+++ b/include/drm/gpu_scheduler.h
@@ -66,6 +66,7 @@ enum drm_sched_priority {
  * @guilty: points to ctx's guilty.
  * @fini_status: contains the exit status in case the process was signalled.
  * @last_scheduled: points to the finished fence of the last scheduled job.
+ * @last_user: last group leader pushing a job into the entity.
  *
  * Entities will emit jobs in order to their corresponding hardware
  * ring, and the scheduler will alternate between entities based on
@@ -85,6 +86,7 @@ struct drm_sched_entity {
        struct dma_fence_cb             cb;
        atomic_t                        *guilty;
        struct dma_fence                *last_scheduled;
+       struct task_struct              *last_user;
 };
 
 /**