[PATCH tip/core/rcu 28/41] slab: Replace synchronize_sched() with synchronize_rcu()

Paul E. McKenney
2018-11-11T19:48:10Z

Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-mm@kvack.org>
---
mm/slab.c | 4 ++--
mm/slab_common.c | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index 2a5654bb3b3f..3abb9feb3818 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -962,10 +962,10 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
* To protect lockless access to n->shared during irq disabled context.
* If n->shared isn't NULL in irq disabled context, accessing to it is
* guaranteed to be valid until irq is re-enabled, because it will be
- * freed after synchronize_sched().
+ * freed after synchronize_rcu().
*/
if (old_shared && force_change)
- synchronize_sched();
+ synchronize_rcu();

fail:
kfree(old_shared);
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 7eb8dc136c1c..9c11e8a937d2 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -724,7 +724,7 @@ void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s,
css_get(&s->memcg_params.memcg->css);

s->memcg_params.deact_fn = deact_fn;
- call_rcu_sched(&s->memcg_params.deact_rcu_head, kmemcg_deactivate_rcufn);
+ call_rcu(&s->memcg_params.deact_rcu_head, kmemcg_deactivate_rcufn);
}

void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg)
@@ -839,11 +839,11 @@ static void flush_memcg_workqueue(struct kmem_cache *s)
mutex_unlock(&slab_mutex);

/*
- * SLUB deactivates the kmem_caches through call_rcu_sched. Make
+ * SLUB deactivates the kmem_caches through call_rcu. Make
* sure all registered rcu callbacks have been invoked.
*/
if (IS_ENABLED(CONFIG_SLUB))
- rcu_barrier_sched();
+ rcu_barrier();

/*
* SLAB and SLUB create memcg kmem_caches through workqueue and SLUB
--
2.17.1