From b13a21890a83411ca399a74eeb785b914359171f Mon Sep 17 00:00:00 2001 From: Gavin Hu Date: Thu, 7 Nov 2019 22:35:26 +0100 Subject: [PATCH] ticketlock: use new API to reduce contention on aarch64 While using ticket lock, cores repeatedly poll the lock variable. This is replaced by rte_wait_until_equal API. Running ticketlock_autotest on ThunderX2, Ampere eMAG80, and Arm N1SDP[1], there were variances between runs, but no notable performance gain or degradation were seen with and without this patch. [1] https://community.arm.com/developer/tools-software/oss-platforms/w/\ docs/440/neoverse-n1-sdp Signed-off-by: Gavin Hu Reviewed-by: Honnappa Nagarahalli Tested-by: Phil Yang Tested-by: Pavan Nikhilesh Reviewed-by: Jerin Jacob --- lib/librte_eal/common/include/generic/rte_ticketlock.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/lib/librte_eal/common/include/generic/rte_ticketlock.h b/lib/librte_eal/common/include/generic/rte_ticketlock.h index d9bec87692..c295ae7f7e 100644 --- a/lib/librte_eal/common/include/generic/rte_ticketlock.h +++ b/lib/librte_eal/common/include/generic/rte_ticketlock.h @@ -66,8 +66,7 @@ static inline void rte_ticketlock_lock(rte_ticketlock_t *tl) { uint16_t me = __atomic_fetch_add(&tl->s.next, 1, __ATOMIC_RELAXED); - while (__atomic_load_n(&tl->s.current, __ATOMIC_ACQUIRE) != me) - rte_pause(); + rte_wait_until_equal_16(&tl->s.current, me, __ATOMIC_ACQUIRE); } /** -- 2.20.1