From af609ea21285797ae3a96a73cf7e6269c302d0ac Mon Sep 17 00:00:00 2001 From: Thomas Gschwantner Date: Sun, 10 Jun 2018 22:19:28 +0200 Subject: mpmc_ptr_ring: calculate mask once and store it --- src/mpmc_ptr_ring.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'src/mpmc_ptr_ring.h') diff --git a/src/mpmc_ptr_ring.h b/src/mpmc_ptr_ring.h index 183aa24..09d56df 100644 --- a/src/mpmc_ptr_ring.h +++ b/src/mpmc_ptr_ring.h @@ -42,6 +42,7 @@ struct mpmc_ptr_ring { /* Read-mostly data */ void **queue; unsigned int size; + unsigned int mask; /* consumer_head: updated in _consume; read in _produce */ atomic_t consumer_head ____cacheline_aligned_in_smp; @@ -67,7 +68,7 @@ static inline bool mpmc_ptr_ring_empty(struct mpmc_ptr_ring *r) static inline int mpmc_ptr_ring_produce(struct mpmc_ptr_ring *r, void *ptr) { unsigned int p, c; - unsigned int mask = r->size - 1; + unsigned int mask = r->mask; p = atomic_read(&r->producer_head); @@ -110,8 +111,8 @@ static inline int mpmc_ptr_ring_produce(struct mpmc_ptr_ring *r, void *ptr) static inline void *mpmc_ptr_ring_consume(struct mpmc_ptr_ring *r) { unsigned int c, p, old_c; + unsigned int mask = r->mask; void *element; - unsigned int mask = r->size - 1; for (;;) { c = atomic_read(&r->consumer_head); @@ -147,6 +148,7 @@ static inline int mpmc_ptr_ring_init(struct mpmc_ptr_ring *r, unsigned int size, return -EINVAL; r->size = size; + r->mask = size - 1; atomic_set(&r->consumer_head, 0); atomic_set(&r->producer_head, 0); atomic_set(&r->producer_tail, 0); @@ -178,7 +180,7 @@ static inline void mpmc_ptr_ring_cleanup(struct mpmc_ptr_ring *r, void (*destroy static inline void *__mpmc_ptr_ring_peek(struct mpmc_ptr_ring *r) { unsigned int c, p; - unsigned int mask = r->size - 1; + unsigned int mask = r->mask; void *element; c = atomic_read(&r->consumer_head); -- cgit v1.2.3-59-g8ed1b