diff options
Diffstat (limited to 'lib/percpu-refcount.c')
| -rw-r--r-- | lib/percpu-refcount.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 5a6d43baccc5..ed280fb1e5b5 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -45,27 +45,40 @@ static unsigned long __percpu *percpu_count_ptr(struct percpu_ref *ref) * percpu_ref_init - initialize a percpu refcount * @ref: percpu_ref to initialize * @release: function which will be called when refcount hits 0 + * @flags: PERCPU_REF_INIT_* flags * @gfp: allocation mask to use * - * Initializes the refcount in single atomic counter mode with a refcount of 1; - * analagous to atomic_long_set(ref, 1). + * Initializes @ref. If @flags is zero, @ref starts in percpu mode with a + * refcount of 1; analagous to atomic_long_set(ref, 1). See the + * definitions of PERCPU_REF_INIT_* flags for flag behaviors. * * Note that @release must not sleep - it may potentially be called from RCU * callback context by percpu_ref_kill(). */ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release, - gfp_t gfp) + unsigned int flags, gfp_t gfp) { size_t align = max_t(size_t, 1 << __PERCPU_REF_FLAG_BITS, __alignof__(unsigned long)); - - atomic_long_set(&ref->count, 1 + PERCPU_COUNT_BIAS); + unsigned long start_count = 0; ref->percpu_count_ptr = (unsigned long) __alloc_percpu_gfp(sizeof(unsigned long), align, gfp); if (!ref->percpu_count_ptr) return -ENOMEM; + if (flags & (PERCPU_REF_INIT_ATOMIC | PERCPU_REF_INIT_DEAD)) + ref->percpu_count_ptr |= __PERCPU_REF_ATOMIC; + else + start_count += PERCPU_COUNT_BIAS; + + if (flags & PERCPU_REF_INIT_DEAD) + ref->percpu_count_ptr |= __PERCPU_REF_DEAD; + else + start_count++; + + atomic_long_set(&ref->count, start_count); + ref->release = release; return 0; } |