Checkpatch.pl warns there are 2 locations of smp_mb() and smp_wmb()
without code comment. This patch adds the missing code comments for
these memory barrier calls.
Signed-off-by: Coly Li <colyli@xxxxxxx>
Cc: Shenghui Wang <shhuiw@xxxxxxxxxxx>
---
drivers/md/bcache/closure.h | 4 +++-
drivers/md/bcache/super.c | 2 +-
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/md/bcache/closure.h b/drivers/md/bcache/closure.h
index 7f3594c0be14..eca0d496b686 100644
--- a/drivers/md/bcache/closure.h
+++ b/drivers/md/bcache/closure.h
@@ -289,10 +289,12 @@ static inline void closure_init_stack(struct closure *cl)
}
/**
- * closure_wake_up - wake up all closures on a wait list.
+ * closure_wake_up - wake up all closures on a wait list,
+ * with memory barrier
*/
static inline void closure_wake_up(struct closure_waitlist *list)
{
+ /* Memory barrier for the wait list */
smp_mb();
__closure_wake_up(list);
}
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index d09c5fe4f758..0dbd1bcb0d38 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1136,11 +1136,11 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
list_move(&dc->list, &c->cached_devs);
calc_cached_dev_sectors(c);
- smp_wmb();
/*
* dc->c must be set before dc->count != 0 - paired with the mb in
* cached_dev_get()
*/
+ smp_wmb();
refcount_set(&dc->count, 1);
/* Block writeback thread, but spawn it */
--
2.18.0
