summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
Diffstat (limited to 'include')
-rw-r--r--include/linux/blkdev.h2
-rw-r--r--include/linux/blktrace_api.h18
2 files changed, 14 insertions, 6 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 053ea4b51988..10455b2bbbb4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -524,7 +524,7 @@ struct request_queue {
unsigned int sg_reserved_size;
int node;
#ifdef CONFIG_BLK_DEV_IO_TRACE
- struct blk_trace *blk_trace;
+ struct blk_trace __rcu *blk_trace;
struct mutex blk_trace_mutex;
#endif
/*
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 7bb2d8de9f30..3b6ff5902edc 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -51,9 +51,13 @@ void __trace_note_message(struct blk_trace *, struct blkcg *blkcg, const char *f
**/
#define blk_add_cgroup_trace_msg(q, cg, fmt, ...) \
do { \
- struct blk_trace *bt = (q)->blk_trace; \
+ struct blk_trace *bt; \
+ \
+ rcu_read_lock(); \
+ bt = rcu_dereference((q)->blk_trace); \
if (unlikely(bt)) \
__trace_note_message(bt, cg, fmt, ##__VA_ARGS__);\
+ rcu_read_unlock(); \
} while (0)
#define blk_add_trace_msg(q, fmt, ...) \
blk_add_cgroup_trace_msg(q, NULL, fmt, ##__VA_ARGS__)
@@ -61,10 +65,14 @@ void __trace_note_message(struct blk_trace *, struct blkcg *blkcg, const char *f
static inline bool blk_trace_note_message_enabled(struct request_queue *q)
{
- struct blk_trace *bt = q->blk_trace;
- if (likely(!bt))
- return false;
- return bt->act_mask & BLK_TC_NOTIFY;
+ struct blk_trace *bt;
+ bool ret;
+
+ rcu_read_lock();
+ bt = rcu_dereference(q->blk_trace);
+ ret = bt && (bt->act_mask & BLK_TC_NOTIFY);
+ rcu_read_unlock();
+ return ret;
}
extern void blk_add_driver_data(struct request_queue *q, struct request *rq,