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 | 45 +++++++++++++++++++++++++++++--------------- include/media/media-entity.h | 3 +++ 2 files changed, 33 insertions(+), 15 deletions(-)
diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c index 49a8755..4bb824b 100644 --- a/drivers/media/media-entity.c +++ b/drivers/media/media-entity.c @@ -397,7 +397,7 @@ EXPORT_SYMBOL_GPL(media_entity_graph_walk_next); */
/** - * media_entity_pipeline_start - Mark a pipeline as streaming + * __media_entity_pipeline_start - Mark a pipeline as streaming * @entity: Starting entity * @pipe: Media pipeline to be assigned to all entities in the pipeline. * @@ -408,19 +408,18 @@ EXPORT_SYMBOL_GPL(media_entity_graph_walk_next); * Calls to this function can be nested, in which case the same number of * media_entity_pipeline_stop() calls will be required to stop streaming. The * pipeline pointer must be identical for all nested calls to - * media_entity_pipeline_start(). + * __media_entity_pipeline_start(). + * User is expected to hold the graph_mutex. If not user can call + * media_entity_pipeline_start() */ -__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; struct media_entity *entity_err = entity; struct media_link *link; int ret;
- mutex_lock(&mdev->graph_mutex); - media_entity_graph_walk_start(&graph, entity);
while ((entity = media_entity_graph_walk_next(&graph))) { @@ -490,8 +489,6 @@ __must_check int media_entity_pipeline_start(struct media_entity *entity, } }
- mutex_unlock(&mdev->graph_mutex); - return 0;
error: @@ -517,14 +514,25 @@ error: break; }
- 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);
/** - * media_entity_pipeline_stop - Mark a pipeline as not streaming + * __media_entity_pipeline_stop - Mark a pipeline as not streaming * @entity: Starting entity * * Mark all entities connected to a given entity through enabled links, either @@ -534,14 +542,13 @@ EXPORT_SYMBOL_GPL(media_entity_pipeline_start); * If multiple calls to media_entity_pipeline_start() have been made, the same * number of calls to this function are required to mark the pipeline as not * streaming. + * User is expected to hold the graph_mutex. If not user can call + * media_entity_pipeline_stop() */ -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;
- mutex_lock(&mdev->graph_mutex); - media_entity_graph_walk_start(&graph, entity);
while ((entity = media_entity_graph_walk_next(&graph))) { @@ -552,7 +559,15 @@ void media_entity_pipeline_stop(struct media_entity *entity) entity->pipe = NULL; } } +} +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 44ab153..3b971f2 100644 --- a/include/media/media-entity.h +++ b/include/media/media-entity.h @@ -365,8 +365,11 @@ void media_entity_graph_walk_start(struct media_entity_graph *graph, struct media_entity *entity); struct media_entity * 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); __must_check int media_entity_pipeline_start(struct media_entity *entity, struct media_pipeline *pipe); +void __media_entity_pipeline_stop(struct media_entity *entity); void media_entity_pipeline_stop(struct media_entity *entity);
struct media_intf_devnode *