diff options
author | Roman Gushchin <guro@fb.com> | 2019-07-11 20:56:09 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-12 11:05:44 -0700 |
commit | 434866947564b954409c2fe561605e22f7b49f64 (patch) | |
tree | 7ee227d29c0d5db895af0a1e953aa8959a41a5f2 | |
parent | 0b14e8aa68223c2c124d408aa4b110b364d13c53 (diff) |
mm: memcg/slab: generalize postponed non-root kmem_cache deactivation
Currently SLUB uses a work scheduled after an RCU grace period to
deactivate a non-root kmem_cache. This mechanism can be reused for
kmem_caches release, but requires generalization for SLAB case.
Introduce kmemcg_cache_deactivate() function, which calls
allocator-specific __kmem_cache_deactivate() and schedules execution of
__kmem_cache_deactivate_after_rcu() with all necessary locks in a worker
context after an rcu grace period.
Here is the new calling scheme:
kmemcg_cache_deactivate()
__kmemcg_cache_deactivate() SLAB/SLUB-specific
kmemcg_rcufn() rcu
kmemcg_workfn() work
__kmemcg_cache_deactivate_after_rcu() SLAB/SLUB-specific
instead of:
__kmemcg_cache_deactivate() SLAB/SLUB-specific
slab_deactivate_memcg_cache_rcu_sched() SLUB-only
kmemcg_rcufn() rcu
kmemcg_workfn() work
kmemcg_cache_deact_after_rcu() SLUB-only
For consistency, all allocator-specific functions start with "__".
Link: http://lkml.kernel.org/r/20190611231813.3148843-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Waiman Long <longman@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | mm/slab.c | 4 | ||||
-rw-r--r-- | mm/slab.h | 3 | ||||
-rw-r--r-- | mm/slab_common.c | 27 | ||||
-rw-r--r-- | mm/slub.c | 8 |
4 files changed, 14 insertions, 28 deletions
diff --git a/mm/slab.c b/mm/slab.c index badd98f7e2f1..30347bd3f19c 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2252,6 +2252,10 @@ void __kmemcg_cache_deactivate(struct kmem_cache *cachep) { __kmem_cache_shrink(cachep); } + +void __kmemcg_cache_deactivate_after_rcu(struct kmem_cache *s) +{ +} #endif int __kmem_cache_shutdown(struct kmem_cache *cachep) diff --git a/mm/slab.h b/mm/slab.h index 7ef695b91919..dc83583ee9dd 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -172,6 +172,7 @@ int __kmem_cache_shutdown(struct kmem_cache *); void __kmem_cache_release(struct kmem_cache *); int __kmem_cache_shrink(struct kmem_cache *); void __kmemcg_cache_deactivate(struct kmem_cache *s); +void __kmemcg_cache_deactivate_after_rcu(struct kmem_cache *s); void slab_kmem_cache_release(struct kmem_cache *); struct seq_file; @@ -290,8 +291,6 @@ static __always_inline void memcg_uncharge_slab(struct page *page, int order, extern void slab_init_memcg_params(struct kmem_cache *); extern void memcg_link_cache(struct kmem_cache *s, struct mem_cgroup *memcg); -extern void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s, - void (*work_fn)(struct kmem_cache *)); #else /* CONFIG_MEMCG_KMEM */ diff --git a/mm/slab_common.c b/mm/slab_common.c index f4dd9f75751c..62733bbcc971 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -708,7 +708,7 @@ static void kmemcg_workfn(struct work_struct *work) put_online_mems(); put_online_cpus(); - /* done, put the ref from slab_deactivate_memcg_cache_rcu_sched() */ + /* done, put the ref from kmemcg_cache_deactivate() */ css_put(&s->memcg_params.memcg->css); } @@ -726,31 +726,21 @@ static void kmemcg_rcufn(struct rcu_head *head) queue_work(memcg_kmem_cache_wq, &s->memcg_params.work); } -/** - * slab_deactivate_memcg_cache_rcu_sched - schedule deactivation after a - * sched RCU grace period - * @s: target kmem_cache - * @work_fn: deactivation function to call - * - * Schedule @work_fn to be invoked with online cpus, mems and slab_mutex - * held after a sched RCU grace period. The slab is guaranteed to stay - * alive until @work_fn is finished. This is to be used from - * __kmemcg_cache_deactivate(). - */ -void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s, - void (*work_fn)(struct kmem_cache *)) +static void kmemcg_cache_deactivate(struct kmem_cache *s) { if (WARN_ON_ONCE(is_root_cache(s)) || WARN_ON_ONCE(s->memcg_params.work_fn)) return; + __kmemcg_cache_deactivate(s); + if (s->memcg_params.root_cache->memcg_params.dying) return; /* pin memcg so that @s doesn't get destroyed in the middle */ css_get(&s->memcg_params.memcg->css); - s->memcg_params.work_fn = work_fn; + s->memcg_params.work_fn = __kmemcg_cache_deactivate_after_rcu; call_rcu(&s->memcg_params.rcu_head, kmemcg_rcufn); } @@ -773,7 +763,7 @@ void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg) if (!c) continue; - __kmemcg_cache_deactivate(c); + kmemcg_cache_deactivate(c); arr->entries[idx] = NULL; } mutex_unlock(&slab_mutex); @@ -866,11 +856,10 @@ static void flush_memcg_workqueue(struct kmem_cache *s) mutex_unlock(&slab_mutex); /* - * SLUB deactivates the kmem_caches through call_rcu. Make + * SLAB and SLUB deactivate the kmem_caches through call_rcu. Make * sure all registered rcu callbacks have been invoked. */ - if (IS_ENABLED(CONFIG_SLUB)) - rcu_barrier(); + rcu_barrier(); /* * SLAB and SLUB create memcg kmem_caches through workqueue and SLUB diff --git a/mm/slub.c b/mm/slub.c index e1402ed19e74..845aeaa6c2d4 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4008,7 +4008,7 @@ int __kmem_cache_shrink(struct kmem_cache *s) } #ifdef CONFIG_MEMCG -static void kmemcg_cache_deact_after_rcu(struct kmem_cache *s) +void __kmemcg_cache_deactivate_after_rcu(struct kmem_cache *s) { /* * Called with all the locks held after a sched RCU grace period. @@ -4034,12 +4034,6 @@ void __kmemcg_cache_deactivate(struct kmem_cache *s) */ slub_set_cpu_partial(s, 0); s->min_partial = 0; - - /* - * s->cpu_partial is checked locklessly (see put_cpu_partial), so - * we have to make sure the change is visible before shrinking. - */ - slab_deactivate_memcg_cache_rcu_sched(s, kmemcg_cache_deact_after_rcu); } #endif /* CONFIG_MEMCG */ |