diff options
| author | Ming Lei <ming.lei@redhat.com> | 2023-11-17 10:35:22 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2023-11-17 10:48:58 -0700 |
| commit | 27b13e209ddca5979847a1b57890e0372c1edcee (patch) | |
| tree | a6bc8f395772ea9f4bb99df0ebb2140cbf8a5013 /block/blk-throttle.c | |
| parent | b0077e269f6c152e807fdac90b58caf012cdbaab (diff) | |
blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!"
Inside blkg_for_each_descendant_pre(), both
css_for_each_descendant_pre() and blkg_lookup() requires RCU read lock,
and either cgroup_assert_mutex_or_rcu_locked() or rcu_read_lock_held()
is called.
Fix the warning by adding rcu read lock.
Reported-by: Changhui Zhong <czhong@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20231117023527.3188627-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-throttle.c')
| -rw-r--r-- | block/blk-throttle.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 13e4377a8b28..16f5766620a4 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1320,6 +1320,7 @@ static void tg_conf_updated(struct throtl_grp *tg, bool global) tg_bps_limit(tg, READ), tg_bps_limit(tg, WRITE), tg_iops_limit(tg, READ), tg_iops_limit(tg, WRITE)); + rcu_read_lock(); /* * Update has_rules[] flags for the updated tg's subtree. A tg is * considered to have rules if either the tg itself or any of its @@ -1347,6 +1348,7 @@ static void tg_conf_updated(struct throtl_grp *tg, bool global) this_tg->latency_target = max(this_tg->latency_target, parent_tg->latency_target); } + rcu_read_unlock(); /* * We're already holding queue_lock and know @tg is valid. Let's |