diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/cgroup.h | 26 | ||||
-rw-r--r-- | include/linux/percpu-refcount.h | 47 |
2 files changed, 64 insertions, 9 deletions
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 1d5196889048..9f96b25965c2 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -113,6 +113,19 @@ static inline void css_get(struct cgroup_subsys_state *css) } /** + * css_get_many - obtain references on the specified css + * @css: target css + * @n: number of references to get + * + * The caller must already have a reference. + */ +static inline void css_get_many(struct cgroup_subsys_state *css, unsigned int n) +{ + if (!(css->flags & CSS_NO_REF)) + percpu_ref_get_many(&css->refcnt, n); +} + +/** * css_tryget - try to obtain a reference on the specified css * @css: target css * @@ -159,6 +172,19 @@ static inline void css_put(struct cgroup_subsys_state *css) percpu_ref_put(&css->refcnt); } +/** + * css_put_many - put css references + * @css: target css + * @n: number of references to put + * + * Put references obtained via css_get() and css_tryget_online(). + */ +static inline void css_put_many(struct cgroup_subsys_state *css, unsigned int n) +{ + if (!(css->flags & CSS_NO_REF)) + percpu_ref_put_many(&css->refcnt, n); +} + /* bits in struct cgroup flags field */ enum { /* Control Group requires release notifications to userspace */ diff --git a/include/linux/percpu-refcount.h b/include/linux/percpu-refcount.h index 51ce60c35f4c..530b249f7ea4 100644 --- a/include/linux/percpu-refcount.h +++ b/include/linux/percpu-refcount.h @@ -147,28 +147,42 @@ static inline bool __ref_is_percpu(struct percpu_ref *ref, } /** - * percpu_ref_get - increment a percpu refcount + * percpu_ref_get_many - increment a percpu refcount * @ref: percpu_ref to get + * @nr: number of references to get * - * Analagous to atomic_long_inc(). + * Analogous to atomic_long_add(). * * This function is safe to call as long as @ref is between init and exit. */ -static inline void percpu_ref_get(struct percpu_ref *ref) +static inline void percpu_ref_get_many(struct percpu_ref *ref, unsigned long nr) { unsigned long __percpu *percpu_count; rcu_read_lock_sched(); if (__ref_is_percpu(ref, &percpu_count)) - this_cpu_inc(*percpu_count); + this_cpu_add(*percpu_count, nr); else - atomic_long_inc(&ref->count); + atomic_long_add(nr, &ref->count); rcu_read_unlock_sched(); } /** + * percpu_ref_get - increment a percpu refcount + * @ref: percpu_ref to get + * + * Analagous to atomic_long_inc(). + * + * This function is safe to call as long as @ref is between init and exit. + */ +static inline void percpu_ref_get(struct percpu_ref *ref) +{ + percpu_ref_get_many(ref, 1); +} + +/** * percpu_ref_tryget - try to increment a percpu refcount * @ref: percpu_ref to try-get * @@ -231,29 +245,44 @@ static inline bool percpu_ref_tryget_live(struct percpu_ref *ref) } /** - * percpu_ref_put - decrement a percpu refcount + * percpu_ref_put_many - decrement a percpu refcount * @ref: percpu_ref to put + * @nr: number of references to put * * Decrement the refcount, and if 0, call the release function (which was passed * to percpu_ref_init()) * * This function is safe to call as long as @ref is between init and exit. */ -static inline void percpu_ref_put(struct percpu_ref *ref) +static inline void percpu_ref_put_many(struct percpu_ref *ref, unsigned long nr) { unsigned long __percpu *percpu_count; rcu_read_lock_sched(); if (__ref_is_percpu(ref, &percpu_count)) - this_cpu_dec(*percpu_count); - else if (unlikely(atomic_long_dec_and_test(&ref->count))) + this_cpu_sub(*percpu_count, nr); + else if (unlikely(atomic_long_sub_and_test(nr, &ref->count))) ref->release(ref); rcu_read_unlock_sched(); } /** + * percpu_ref_put - decrement a percpu refcount + * @ref: percpu_ref to put + * + * Decrement the refcount, and if 0, call the release function (which was passed + * to percpu_ref_init()) + * + * This function is safe to call as long as @ref is between init and exit. + */ +static inline void percpu_ref_put(struct percpu_ref *ref) +{ + percpu_ref_put_many(ref, 1); +} + +/** * percpu_ref_is_zero - test whether a percpu refcount reached zero * @ref: percpu_ref to test * |