diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/memcontrol.h | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 1b79760af685..07eadf7ecbba 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -366,11 +366,11 @@ static inline bool folio_memcg_kmem(struct folio *folio); * After the initialization objcg->memcg is always pointing at * a valid memcg, but can be atomically swapped to the parent memcg. * - * The caller must ensure that the returned memcg won't be released: - * e.g. acquire the rcu_read_lock or css_set_lock. + * The caller must ensure that the returned memcg won't be released. */ static inline struct mem_cgroup *obj_cgroup_memcg(struct obj_cgroup *objcg) { + lockdep_assert_once(rcu_read_lock_held() || lockdep_is_held(&cgroup_mutex)); return READ_ONCE(objcg->memcg); } @@ -444,6 +444,19 @@ static inline struct mem_cgroup *folio_memcg(struct folio *folio) return __folio_memcg(folio); } +/* + * folio_memcg_charged - If a folio is charged to a memory cgroup. + * @folio: Pointer to the folio. + * + * Returns true if folio is charged to a memory cgroup, otherwise returns false. + */ +static inline bool folio_memcg_charged(struct folio *folio) +{ + if (folio_memcg_kmem(folio)) + return __folio_objcg(folio) != NULL; + return __folio_memcg(folio) != NULL; +} + /** * folio_memcg_rcu - Locklessly get the memory cgroup associated with a folio. * @folio: Pointer to the folio. @@ -460,7 +473,6 @@ static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio) unsigned long memcg_data = READ_ONCE(folio->memcg_data); VM_BUG_ON_FOLIO(folio_test_slab(folio), folio); - WARN_ON_ONCE(!rcu_read_lock_held()); if (memcg_data & MEMCG_DATA_KMEM) { struct obj_cgroup *objcg; @@ -469,6 +481,8 @@ static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio) return obj_cgroup_memcg(objcg); } + WARN_ON_ONCE(!rcu_read_lock_held()); + return (struct mem_cgroup *)(memcg_data & ~OBJEXTS_FLAGS_MASK); } |