diff options
Diffstat (limited to 'block/blk-ioc.c')
| -rw-r--r-- | block/blk-ioc.c | 36 |
1 files changed, 25 insertions, 11 deletions
diff --git a/block/blk-ioc.c b/block/blk-ioc.c index 10928740b5d..439ec21fd78 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -149,20 +149,20 @@ void put_io_context(struct io_context *ioc) } EXPORT_SYMBOL(put_io_context); -/* Called by the exiting task */ -void exit_io_context(struct task_struct *task) +/** + * put_io_context_active - put active reference on ioc + * @ioc: ioc of interest + * + * Undo get_io_context_active(). If active reference reaches zero after + * put, @ioc can never issue further IOs and ioscheds are notified. + */ +void put_io_context_active(struct io_context *ioc) { - struct io_context *ioc; - struct io_cq *icq; struct hlist_node *n; unsigned long flags; + struct io_cq *icq; - task_lock(task); - ioc = task->io_context; - task->io_context = NULL; - task_unlock(task); - - if (!atomic_dec_and_test(&ioc->nr_tasks)) { + if (!atomic_dec_and_test(&ioc->active_ref)) { put_io_context(ioc); return; } @@ -191,6 +191,20 @@ retry: put_io_context(ioc); } +/* Called by the exiting task */ +void exit_io_context(struct task_struct *task) +{ + struct io_context *ioc; + + task_lock(task); + ioc = task->io_context; + task->io_context = NULL; + task_unlock(task); + + atomic_dec(&ioc->nr_tasks); + put_io_context_active(ioc); +} + /** * ioc_clear_queue - break any ioc association with the specified queue * @q: request_queue being cleared @@ -223,7 +237,7 @@ int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, int node) /* initialize */ atomic_long_set(&ioc->refcount, 1); - atomic_set(&ioc->nr_tasks, 1); + atomic_set(&ioc->active_ref, 1); spin_lock_init(&ioc->lock); INIT_RADIX_TREE(&ioc->icq_tree, GFP_ATOMIC | __GFP_HIGH); INIT_HLIST_HEAD(&ioc->icq_list); |