diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index d5d94510afd3..1af3c8aa78a3 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -311,7 +311,7 @@ static void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, local_irq_restore(flags); } -static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) +static void blk_trace_free_top(struct request_queue *q, struct blk_trace *bt) { relay_close(bt->rchan); @@ -325,11 +325,21 @@ static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) } else { debugfs_remove(bt->dir); } +} + +static void blk_trace_free_bt(struct blk_trace *bt) +{ free_percpu(bt->sequence); free_percpu(bt->msg_data); kfree(bt); } +static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) +{ + blk_trace_free_top(q, bt); + blk_trace_free_bt(bt); +} + static void get_probe_ref(void) { mutex_lock(&blk_probe_mutex); @@ -377,12 +387,23 @@ static int blk_trace_stop(struct blk_trace *bt) return 0; } +static void blk_trace_rcu_free(struct rcu_head *rcu) +{ + struct blk_trace *bt; + + bt = container_of(rcu, struct blk_trace, rcu); + if (bt) + blk_trace_free_bt(bt); +} + static void blk_trace_cleanup(struct request_queue *q, struct blk_trace *bt) { blk_trace_stop(bt); - synchronize_rcu(); - blk_trace_free(q, bt); + mutex_unlock(&q->debugfs_mutex); + blk_trace_free_top(q, bt); put_probe_ref(); + call_rcu(&bt->rcu, blk_trace_rcu_free); + mutex_lock(&q->debugfs_mutex); } static int __blk_trace_remove(struct request_queue *q) diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h index 122c62e561fc..5f927328b7e6 100644 --- a/include/linux/blktrace_api.h +++ b/include/linux/blktrace_api.h @@ -26,6 +26,7 @@ struct blk_trace { struct dentry *dir; struct list_head running_list; atomic_t dropped; + struct rcu_head rcu; }; extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);