Add non-locking __media_entity_pipeline_start/stop() interfaces to be called from code paths that hold the graph_mutex. For this change, the media_entity_pipeline_start() routine is renamed to __media_entity_pipeline_start() minus the graph_mutex lock and unlock. media_entity_pipeline_start() now calls the non-locking __media_entity_pipeline_start() holding the graph_lock. The stop interface, media_entity_pipeline_stop() routine is renamed to __media_entity_pipeline_stop() minus the graph_mutex lock and unlock. media_entity_pipeline_stop() now calls the non-locking __media_entity_pipeline_stop() holding the graph_lock.
Signed-off-by: Shuah Khan shuahkh@osg.samsung.com --- drivers/media/media-entity.c | 34 ++++++++++++++++++++++++---------- include/media/media-entity.h | 12 ++++++++++++ 2 files changed, 36 insertions(+), 10 deletions(-)
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c index b8769aa..270ade2 100644 --- a/drivers/media/media-entity.c +++ b/drivers/media/media-entity.c @@ -361,8 +361,8 @@ EXPORT_SYMBOL_GPL(media_entity_graph_walk_next); * Pipeline management */
-__must_check int media_entity_pipeline_start(struct media_entity *entity, - struct media_pipeline *pipe) +__must_check int __media_entity_pipeline_start(struct media_entity *entity, + struct media_pipeline *pipe) { struct media_device *mdev = entity->graph_obj.mdev; struct media_entity_graph *graph = &pipe->graph; @@ -370,8 +370,6 @@ __must_check int media_entity_pipeline_start(struct media_entity *entity, struct media_link *link; int ret;
- mutex_lock(&mdev->graph_mutex); - if (!pipe->streaming_count++) { ret = media_entity_graph_walk_init(&pipe->graph, mdev); if (ret) @@ -452,8 +450,6 @@ __must_check int media_entity_pipeline_start(struct media_entity *entity, } }
- mutex_unlock(&mdev->graph_mutex); - return 0;
error: @@ -483,19 +479,28 @@ error_graph_walk_start: if (!--pipe->streaming_count) media_entity_graph_walk_cleanup(graph);
- mutex_unlock(&mdev->graph_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(__media_entity_pipeline_start);
+__must_check int media_entity_pipeline_start(struct media_entity *entity, + struct media_pipeline *pipe) +{ + struct media_device *mdev = entity->graph_obj.mdev; + int ret; + + mutex_lock(&mdev->graph_mutex); + ret = __media_entity_pipeline_start(entity, pipe); + mutex_unlock(&mdev->graph_mutex); return ret; } EXPORT_SYMBOL_GPL(media_entity_pipeline_start);
-void media_entity_pipeline_stop(struct media_entity *entity) +void __media_entity_pipeline_stop(struct media_entity *entity) { - struct media_device *mdev = entity->graph_obj.mdev; struct media_entity_graph *graph = &entity->pipe->graph; struct media_pipeline *pipe = entity->pipe;
- mutex_lock(&mdev->graph_mutex);
WARN_ON(!pipe->streaming_count); media_entity_graph_walk_start(graph, entity); @@ -512,6 +517,15 @@ void media_entity_pipeline_stop(struct media_entity *entity) if (!--pipe->streaming_count) media_entity_graph_walk_cleanup(graph);
+} +EXPORT_SYMBOL_GPL(__media_entity_pipeline_stop); + +void media_entity_pipeline_stop(struct media_entity *entity) +{ + struct media_device *mdev = entity->graph_obj.mdev; + + mutex_lock(&mdev->graph_mutex); + __media_entity_pipeline_stop(entity); mutex_unlock(&mdev->graph_mutex); } EXPORT_SYMBOL_GPL(media_entity_pipeline_stop); diff --git a/include/media/media-entity.h b/include/media/media-entity.h index 79dd81f..3f4f577 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -781,6 +781,12 @@ media_entity_graph_walk_next(struct media_entity_graph *graph); */ __must_check int media_entity_pipeline_start(struct media_entity *entity, struct media_pipeline *pipe); +/** + * non-locking __media_entity_pipeline_start() can be called from + * code paths that hold the graph_mutex + */ +__must_check int __media_entity_pipeline_start(struct media_entity *entity, + struct media_pipeline *pipe);
/** * media_entity_pipeline_stop - Mark a pipeline as not streaming @@ -797,6 +803,12 @@ __must_check int media_entity_pipeline_start(struct media_entity *entity, void media_entity_pipeline_stop(struct media_entity *entity);
/** + * non-locking __media_entity_pipeline_stop() can be called from + * code paths that hold the graph_mutex + */ +void __media_entity_pipeline_stop(struct media_entity *entity); + +/** * media_devnode_create() - creates and initializes a device node interface * * @mdev: pointer to struct &media_device