| Message ID | 20240807-b4-slab-kfree_rcu-destroy-v2-3-ea79102f428c@suse.cz (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f77d0cda4a8ebd070bfa1ef9a153c470ea3601ce |
| Headers | show |
| Series | mm, slub: handle pending kfree_rcu() in kmem_cache_destroy() | expand |
On Wed, Aug 7, 2024 at 12:31 PM Vlastimil Babka <vbabka@suse.cz> wrote: > kfence_shutdown_cache() is called under slab_mutex when the cache is > destroyed synchronously, and outside slab_mutex during the delayed > destruction of SLAB_TYPESAFE_BY_RCU caches. > > It seems it should always be safe to call it outside of slab_mutex so we > can just move the call to kmem_cache_release(), which is called outside. > > Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Jann Horn <jannh@google.com>
diff --git a/mm/slab_common.c b/mm/slab_common.c index db61df3b4282..a079b8540334 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -492,6 +492,7 @@ EXPORT_SYMBOL(kmem_buckets_create); */ static void kmem_cache_release(struct kmem_cache *s) { + kfence_shutdown_cache(s); if (__is_defined(SLAB_SUPPORTS_SYSFS) && slab_state >= FULL) sysfs_slab_release(s); else @@ -521,10 +522,8 @@ static void slab_caches_to_rcu_destroy_workfn(struct work_struct *work) rcu_barrier(); - list_for_each_entry_safe(s, s2, &to_destroy, list) { - kfence_shutdown_cache(s); + list_for_each_entry_safe(s, s2, &to_destroy, list) kmem_cache_release(s); - } } void slab_kmem_cache_release(struct kmem_cache *s) @@ -563,9 +562,6 @@ void kmem_cache_destroy(struct kmem_cache *s) list_del(&s->list); - if (!err && !rcu_set) - kfence_shutdown_cache(s); - mutex_unlock(&slab_mutex); cpus_read_unlock();
kfence_shutdown_cache() is called under slab_mutex when the cache is destroyed synchronously, and outside slab_mutex during the delayed destruction of SLAB_TYPESAFE_BY_RCU caches. It seems it should always be safe to call it outside of slab_mutex so we can just move the call to kmem_cache_release(), which is called outside. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> --- mm/slab_common.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)