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| author | Pavel Begunkov <asml.silence@gmail.com> | 2019-12-28 14:13:02 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-01-21 03:04:02 +0300 |
| commit | 4e5ef02317b12e2ed3d604281ffb6b75261f7612 (patch) | |
| tree | 8e8eb1b2959b724ea9d92b34f5b03fb9829f729d /include/linux/percpu-refcount.h | |
| parent | c1ca757bd6f4632c510714631ddcc2d13030fe1e (diff) | |
| download | linux-4e5ef02317b12e2ed3d604281ffb6b75261f7612.tar.xz | |
pcpu_ref: add percpu_ref_tryget_many()
Add percpu_ref_tryget_many(), which works the same way as
percpu_ref_tryget(), but grabs specified number of refs.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/percpu-refcount.h')
| -rw-r--r-- | include/linux/percpu-refcount.h | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/include/linux/percpu-refcount.h b/include/linux/percpu-refcount.h index 390031e816dc..22d9d183950d 100644 --- a/include/linux/percpu-refcount.h +++ b/include/linux/percpu-refcount.h @@ -210,15 +210,17 @@ static inline void percpu_ref_get(struct percpu_ref *ref) } /** - * percpu_ref_tryget - try to increment a percpu refcount + * percpu_ref_tryget_many - try to increment a percpu refcount * @ref: percpu_ref to try-get + * @nr: number of references to get * - * Increment a percpu refcount unless its count already reached zero. + * Increment a percpu refcount by @nr unless its count already reached zero. * Returns %true on success; %false on failure. * * This function is safe to call as long as @ref is between init and exit. */ -static inline bool percpu_ref_tryget(struct percpu_ref *ref) +static inline bool percpu_ref_tryget_many(struct percpu_ref *ref, + unsigned long nr) { unsigned long __percpu *percpu_count; bool ret; @@ -226,10 +228,10 @@ static inline bool percpu_ref_tryget(struct percpu_ref *ref) rcu_read_lock(); if (__ref_is_percpu(ref, &percpu_count)) { - this_cpu_inc(*percpu_count); + this_cpu_add(*percpu_count, nr); ret = true; } else { - ret = atomic_long_inc_not_zero(&ref->count); + ret = atomic_long_add_unless(&ref->count, nr, 0); } rcu_read_unlock(); @@ -238,6 +240,20 @@ static inline bool percpu_ref_tryget(struct percpu_ref *ref) } /** + * percpu_ref_tryget - try to increment a percpu refcount + * @ref: percpu_ref to try-get + * + * Increment a percpu refcount unless its count already reached zero. + * Returns %true on success; %false on failure. + * + * This function is safe to call as long as @ref is between init and exit. + */ +static inline bool percpu_ref_tryget(struct percpu_ref *ref) +{ + return percpu_ref_tryget_many(ref, 1); +} + +/** * percpu_ref_tryget_live - try to increment a live percpu refcount * @ref: percpu_ref to try-get * |