diff options
author | Bart Van Assche <bart.vanassche@wdc.com> | 2018-01-17 11:48:09 -0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-01-18 12:54:42 -0700 |
commit | 14a23498ba97683c6790b1bcd8b2cdfe9ad99797 (patch) | |
tree | 2fd6541a0cb24db6f70ca2ee5ae54675531b273a | |
parent | 83d016ac86428dbca8a62d3e4fdc29e3ea39e535 (diff) | |
download | linux-14a23498ba97683c6790b1bcd8b2cdfe9ad99797.tar.bz2 |
block: Document scheduler modification locking requirements
This patch does not change any functionality.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | block/elevator.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/block/elevator.c b/block/elevator.c index 4f00b53cd5fd..e87e9b43aba0 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -869,6 +869,8 @@ int elv_register_queue(struct request_queue *q) struct elevator_queue *e = q->elevator; int error; + lockdep_assert_held(&q->sysfs_lock); + error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched"); if (!error) { struct elv_fs_entry *attr = e->type->elevator_attrs; @@ -889,6 +891,8 @@ int elv_register_queue(struct request_queue *q) void elv_unregister_queue(struct request_queue *q) { + lockdep_assert_held(&q->sysfs_lock); + if (q) { struct elevator_queue *e = q->elevator; @@ -965,6 +969,8 @@ static int elevator_switch_mq(struct request_queue *q, { int ret; + lockdep_assert_held(&q->sysfs_lock); + blk_mq_freeze_queue(q); blk_mq_quiesce_queue(q); @@ -1010,6 +1016,8 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e) bool old_registered = false; int err; + lockdep_assert_held(&q->sysfs_lock); + if (q->mq_ops) return elevator_switch_mq(q, new_e); |