diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2024-05-28 17:13:41 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-06-06 05:19:24 +0300 |
| commit | 36eef400c2d571d05b6e41a9a61f874d4a7b82c5 (patch) | |
| tree | 572affcd5b3e28c543e361fc4f3bbecd622d069b /mm/memcontrol.c | |
| parent | 6434e69814b159608a23135ca2be36024f402717 (diff) | |
| download | linux-36eef400c2d571d05b6e41a9a61f874d4a7b82c5.tar.xz | |
memcg: remove the lockdep assert from __mod_objcg_mlstate()
The assert was introduced in the commit cited below as an insurance that
the semantic is the same after the local_irq_save() has been removed and
the function has been made static.
The original requirement to disable interrupt was due the modification
of per-CPU counters which require interrupts to be disabled because the
counter update operation is not atomic and some of the counters are
updated from interrupt context.
All callers of __mod_objcg_mlstate() acquire a lock
(memcg_stock.stock_lock) which disables interrupts on !PREEMPT_RT and
the lockdep assert is satisfied. On PREEMPT_RT the interrupts are not
disabled and the assert triggers.
The safety of the counter update is already ensured by
VM_WARN_ON_IRQS_ENABLED() which is part of __mod_memcg_lruvec_state() and
does not require yet another check.
Remove the lockdep assert from __mod_objcg_mlstate().
Link: https://lkml.kernel.org/r/20240528141341.rz_rytN_@linutronix.de
Fixes: 91882c1617c1 ("memcg: simple cleanup of stats update functions")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7fad15b2290c..36793e509f47 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3147,8 +3147,6 @@ static inline void __mod_objcg_mlstate(struct obj_cgroup *objcg, struct mem_cgroup *memcg; struct lruvec *lruvec; - lockdep_assert_irqs_disabled(); - rcu_read_lock(); memcg = obj_cgroup_memcg(objcg); lruvec = mem_cgroup_lruvec(memcg, pgdat); |