From patchwork Sun Jun 30 16:21:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Hu X-Patchwork-Id: 55671 Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id F2A8A1B998; Sun, 30 Jun 2019 18:21:50 +0200 (CEST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by dpdk.org (Postfix) with ESMTP id 6E97B1B96B for ; Sun, 30 Jun 2019 18:21:46 +0200 (CEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id EF47E13D5; Sun, 30 Jun 2019 09:21:45 -0700 (PDT) Received: from net-arm-thunderx2.shanghai.arm.com (net-arm-thunderx2.shanghai.arm.com [10.169.40.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 14F9F3F718; Sun, 30 Jun 2019 09:21:43 -0700 (PDT) From: Gavin Hu To: dev@dpdk.org Cc: thomas@monjalon.net, jerinj@marvell.com, hemant.agrawal@nxp.com, bruce.richardson@intel.com, chaozhu@linux.vnet.ibm.com, Honnappa.Nagarahalli@arm.com, nd@arm.com, gavin.hu@arm.com Date: Mon, 1 Jul 2019 00:21:14 +0800 Message-Id: <1561911676-37718-4-git-send-email-gavin.hu@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1561911676-37718-1-git-send-email-gavin.hu@arm.com> References: <1561911676-37718-1-git-send-email-gavin.hu@arm.com> Subject: [dpdk-dev] [RFC 3/5] ring: use wfe to wait for ring tail update on aarch64 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Instead of polling for tail to be updated, use wfe instruction. 50%~70% performance gain was measured by running ring_perf_autotest on ThunderX2. Signed-off-by: Gavin Hu Reviewed-by: Ruifeng Wang Reviewed-by: Steve Capper Reviewed-by: Ola Liljedahl Reviewed-by: Honnappa Nagarahalli --- lib/librte_ring/rte_ring_c11_mem.h | 5 +++-- lib/librte_ring/rte_ring_generic.h | 4 ++-- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/lib/librte_ring/rte_ring_c11_mem.h b/lib/librte_ring/rte_ring_c11_mem.h index 0fb73a3..f1de79c 100644 --- a/lib/librte_ring/rte_ring_c11_mem.h +++ b/lib/librte_ring/rte_ring_c11_mem.h @@ -2,6 +2,7 @@ * * Copyright (c) 2017,2018 HXT-semitech Corporation. * Copyright (c) 2007-2009 Kip Macy kmacy@freebsd.org + * Copyright (c) 2019 Arm Limited * All rights reserved. * Derived from FreeBSD's bufring.h * Used as BSD-3 Licensed with permission from Kip Macy. @@ -21,8 +22,8 @@ update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val, * we need to wait for them to complete */ if (!single) - while (unlikely(ht->tail != old_val)) - rte_pause(); + if (unlikely(ht->tail != old_val)) + rte_wait_until_equal_relaxed(&ht->tail, old_val); __atomic_store_n(&ht->tail, new_val, __ATOMIC_RELEASE); } diff --git a/lib/librte_ring/rte_ring_generic.h b/lib/librte_ring/rte_ring_generic.h index 953cdbb..bb0dce0 100644 --- a/lib/librte_ring/rte_ring_generic.h +++ b/lib/librte_ring/rte_ring_generic.h @@ -23,8 +23,8 @@ update_tail(struct rte_ring_headtail *ht, uint32_t old_val, uint32_t new_val, * we need to wait for them to complete */ if (!single) - while (unlikely(ht->tail != old_val)) - rte_pause(); + if (unlikely(ht->tail != old_val)) + rte_wait_until_equal_relaxed(&ht->tail, old_val); ht->tail = new_val; }