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| author | Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> | 2020-01-18 08:40:51 +0530 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2020-02-12 17:12:22 -0500 |
| commit | 3010c5b9f5f476b35b24955f08a3a6c06ec8e878 (patch) | |
| tree | 93d94005cefb24a84c181b2fa940d2b8c56117f0 | |
| parent | 04189382c0be4e045d63a38b47f012a8f6c35edc (diff) | |
| download | linux-3010c5b9f5f476b35b24955f08a3a6c06ec8e878.tar.bz2 | |
cgroup.c: Use built-in RCU list checking
list_for_each_entry_rcu has built-in RCU and lock checking.
Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.
Even though the function css_next_child() already checks if
cgroup_mutex or rcu_read_lock() is held using
cgroup_assert_mutex_or_rcu_locked(), there is a need to pass
cond to list_for_each_entry_rcu() to avoid false positive
lockdep warning.
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
| -rw-r--r-- | kernel/cgroup/cgroup.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index b4c4c4fbd6de..7a310db6c807 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -4148,7 +4148,8 @@ struct cgroup_subsys_state *css_next_child(struct cgroup_subsys_state *pos, } else if (likely(!(pos->flags & CSS_RELEASED))) { next = list_entry_rcu(pos->sibling.next, struct cgroup_subsys_state, sibling); } else { - list_for_each_entry_rcu(next, &parent->children, sibling) + list_for_each_entry_rcu(next, &parent->children, sibling, + lockdep_is_held(&cgroup_mutex)) if (next->serial_nr > pos->serial_nr) break; } |