For improved performance over the current C11 based ring implementation, two ACQUIRE fences between the load of the old_head and the load of the const_tail in __rte_ring_move_prod_head and the load of old_head and load of the prod_tail in __rte_ring_move_cons_head functions have been removed. These two fences are not required for the safety of the ring library.
Signed-off-by: Wathsala Vithanage <[email protected]> Reviewed-by: Honnappa Nagarahalli <[email protected]> Reviewed-by: Ruifeng Wang <[email protected]> --- .mailmap | 1 + lib/ring/rte_ring_c11_pvt.h | 6 ------ 2 files changed, 1 insertion(+), 6 deletions(-) diff --git a/.mailmap b/.mailmap index 4018f0fc47..367115d134 100644 --- a/.mailmap +++ b/.mailmap @@ -1430,6 +1430,7 @@ Walter Heymans <[email protected]> Wang Sheng-Hui <[email protected]> Wangyu (Eric) <[email protected]> Waterman Cao <[email protected]> +Wathsala Vithanage <[email protected]> Weichun Chen <[email protected]> Wei Dai <[email protected]> Weifeng Li <[email protected]> diff --git a/lib/ring/rte_ring_c11_pvt.h b/lib/ring/rte_ring_c11_pvt.h index f895950df4..eb59c61b6a 100644 --- a/lib/ring/rte_ring_c11_pvt.h +++ b/lib/ring/rte_ring_c11_pvt.h @@ -66,9 +66,6 @@ __rte_ring_move_prod_head(struct rte_ring *r, unsigned int is_sp, /* Reset n to the initial burst count */ n = max; - /* Ensure the head is read before tail */ - __atomic_thread_fence(__ATOMIC_ACQUIRE); - /* load-acquire synchronize with store-release of ht->tail * in update_tail. */ @@ -142,9 +139,6 @@ __rte_ring_move_cons_head(struct rte_ring *r, int is_sc, /* Restore n as it may change every loop */ n = max; - /* Ensure the head is read before tail */ - __atomic_thread_fence(__ATOMIC_ACQUIRE); - /* this load-acquire synchronize with store-release of ht->tail * in update_tail. */ -- 2.25.1
