diff options
| author | Nilay Shroff <nilay@linux.ibm.com> | 2025-03-04 15:52:35 +0530 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-03-10 07:30:18 -0600 |
| commit | 245618f8e45ff4f79327627b474b563da71c2c75 (patch) | |
| tree | 83cf4a7035fd4b8f0312edfab3263d7e568da9aa /include/linux/blkdev.h | |
| parent | 3efe7571c3ae2b6481253a2616c2bb3fbadd503b (diff) | |
block: protect wbt_lat_usec using q->elevator_lock
The wbt latency and state could be updated while initializing the
elevator or exiting the elevator. It could be also updated while
configuring IO latency QoS parameters using cgroup. The elevator
code path is now protected with q->elevator_lock. So we should
protect the access to sysfs attribute wbt_lat_usec using q->elevator
_lock instead of q->sysfs_lock. White we're at it, also protect
ioc_qos_write(), which configures wbt parameters via cgroup, using
q->elevator_lock.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Link: https://lore.kernel.org/r/20250304102551.2533767-7-nilay@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/blkdev.h')
| -rw-r--r-- | include/linux/blkdev.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 3e66ad016a23..0ee3b5c9388e 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -563,8 +563,8 @@ struct request_queue { /* * Protects against I/O scheduler switching, particularly when * updating q->elevator. Since the elevator update code path may - * also modify q->nr_requests, this lock also protects the sysfs - * attribute nr_requests. + * also modify q->nr_requests and wbt latency, this lock also + * protects the sysfs attributes nr_requests and wbt_lat_usec. * To ensure proper locking order during an elevator update, first * freeze the queue, then acquire ->elevator_lock. */ |