From patchwork Tue Mar 10 17:49:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Yang X-Patchwork-Id: 184359 Delivered-To: patch@linaro.org Received: by 2002:a92:1f12:0:0:0:0:0 with SMTP id i18csp985469ile; Tue, 10 Mar 2020 10:51:25 -0700 (PDT) X-Google-Smtp-Source: ADFU+vtULBVTTNAXFJozwrjAioQb0XZXpvgvJjtnOmpscZ5IbLG8cRR4ppJYuNlYc3wrH3vjpPSD X-Received: by 2002:a17:906:5ad4:: with SMTP id x20mr19546864ejs.293.1583862685276; Tue, 10 Mar 2020 10:51:25 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1583862685; cv=none; d=google.com; s=arc-20160816; b=odgRJTlW57pFFN9YiD5z9Ybck5VXRLncbiScCpUxubj350w/+w/sB1b1mDzi6Hcyvm 259uyxx5L2Fv4o6vRSvfN+CeXA2vA0vql8ftZMq6Y19tHHNAjhdlGdVt1npgDaJBzgCr 8S+J1iyDC1l2DxMN2Qf1viyAK7UKKYHNcXscULWln1uS0lksV1M3s371lCwfIJRKoVCd yoCLaZnKkCK8gXeFXhIU1qiHYS2VDbAwSvqr/ejXfgqJu6KmH9T/QlKU5Og7SPJ6DQUs El6+zY4pPaev21JPrSnLD1H2WFJCivRZ2Bv1UmY5dRJHzrgHh5HVS6wVX/GE1PDCjvoR 3N5w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:list-subscribe:list-help:list-post:list-archive :list-unsubscribe:list-id:precedence:subject:references:in-reply-to :message-id:date:cc:to:from; bh=RZHFv/Qv7vl2sNj8+4vVKdprI4GzcG6ZQgRHYGc2vhM=; b=nK9sVR4t2DNTe0J6l+Ef6qONIuUngk3fuqJssseedTo2kb8xWeKrChWY1Yw+nLVsjt eis2nWtNFhXg3D8C7FSyo8dcyi0VxNtsd1przr/i/7QcqsRnY1hPC0F6aKq8chzHqy4O rLhMqEL76O/wx8xeRu35dPeC5AEgzw0uVo0cMFpFTK3oIIcXYqsf2kH2ilxY674kyWVh 1pxDsFEo1LjLY6ypQHApZRfWIlxB7wjo4F0EGPGqGmklwCHwHhRbdfneQucvsG44tJEw Nnh4hzXFyzy2OAJqj4Bc/y//aZs82O3MV+0yO5OVVwCpwFPGYHad+rsbXagp/JZzST0J G9yQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of dev-bounces@dpdk.org designates 92.243.14.124 as permitted sender) smtp.mailfrom=dev-bounces@dpdk.org Return-Path: Received: from dpdk.org (dpdk.org. [92.243.14.124]) by mx.google.com with ESMTP id f10si9138638eja.201.2020.03.10.10.51.25; Tue, 10 Mar 2020 10:51:25 -0700 (PDT) Received-SPF: pass (google.com: domain of dev-bounces@dpdk.org designates 92.243.14.124 as permitted sender) client-ip=92.243.14.124; Authentication-Results: mx.google.com; spf=pass (google.com: domain of dev-bounces@dpdk.org designates 92.243.14.124 as permitted sender) smtp.mailfrom=dev-bounces@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 16AA41C0D0; Tue, 10 Mar 2020 18:50:29 +0100 (CET) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by dpdk.org (Postfix) with ESMTP id 8C5271C0D0; Tue, 10 Mar 2020 18:50:27 +0100 (CET) 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 1F2921FB; Tue, 10 Mar 2020 10:50:27 -0700 (PDT) Received: from phil-VirtualBox.arm.com (A010647.Arm.com [10.170.243.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D1D383F534; Tue, 10 Mar 2020 10:50:22 -0700 (PDT) From: Phil Yang To: thomas@monjalon.net, harry.van.haaren@intel.com, konstantin.ananyev@intel.com, stephen@networkplumber.org, maxime.coquelin@redhat.com, dev@dpdk.org Cc: david.marchand@redhat.com, jerinj@marvell.com, hemant.agrawal@nxp.com, Honnappa.Nagarahalli@arm.com, gavin.hu@arm.com, ruifeng.wang@arm.com, joyce.kong@arm.com, nd@arm.com, Honnappa Nagarahalli , stable@dpdk.org Date: Wed, 11 Mar 2020 01:49:09 +0800 Message-Id: <1583862551-2049-9-git-send-email-phil.yang@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1583862551-2049-1-git-send-email-phil.yang@arm.com> References: <1583862551-2049-1-git-send-email-phil.yang@arm.com> Subject: [dpdk-dev] [PATCH 08/10] service: identify service running on another core correctly 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" From: Honnappa Nagarahalli The logic to identify if the MT unsafe service is running on another core can return -EBUSY spuriously. In such cases, running the service becomes more costlier than using atomic operations. Assume that the application passes the right parameters and reduce the number of instructions for all cases. Cc: stable@dpdk.org Signed-off-by: Honnappa Nagarahalli Reviewed-by: Phil Yang --- lib/librte_eal/common/rte_service.c | 26 ++++++++------------------ 1 file changed, 8 insertions(+), 18 deletions(-) -- 2.7.4 diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c index b37fc56..0186024 100644 --- a/lib/librte_eal/common/rte_service.c +++ b/lib/librte_eal/common/rte_service.c @@ -357,7 +357,7 @@ service_runner_do_callback(struct rte_service_spec_impl *s, /* Expects the service 's' is valid. */ static int32_t service_run(uint32_t i, struct core_state *cs, uint64_t service_mask, - struct rte_service_spec_impl *s) + struct rte_service_spec_impl *s, uint32_t serialize_mt_unsafe) { if (!s) return -EINVAL; @@ -371,7 +371,7 @@ service_run(uint32_t i, struct core_state *cs, uint64_t service_mask, cs->service_active_on_lcore[i] = 1; - if (service_mt_safe(s) == 0) { + if ((service_mt_safe(s) == 0) && (serialize_mt_unsafe == 1)) { if (!rte_atomic32_cmpset((uint32_t *)&s->execute_lock, 0, 1)) return -EBUSY; @@ -409,24 +409,14 @@ rte_service_run_iter_on_app_lcore(uint32_t id, uint32_t serialize_mt_unsafe) SERVICE_VALID_GET_OR_ERR_RET(id, s, -EINVAL); - /* Atomically add this core to the mapped cores first, then examine if - * we can run the service. This avoids a race condition between - * checking the value, and atomically adding to the mapped count. + /* Increment num_mapped_cores to indicate that the service is + * is running on a core. */ - if (serialize_mt_unsafe) - rte_atomic32_inc(&s->num_mapped_cores); + rte_atomic32_inc(&s->num_mapped_cores); - if (service_mt_safe(s) == 0 && - rte_atomic32_read(&s->num_mapped_cores) > 1) { - if (serialize_mt_unsafe) - rte_atomic32_dec(&s->num_mapped_cores); - return -EBUSY; - } - - int ret = service_run(id, cs, UINT64_MAX, s); + int ret = service_run(id, cs, UINT64_MAX, s, serialize_mt_unsafe); - if (serialize_mt_unsafe) - rte_atomic32_dec(&s->num_mapped_cores); + rte_atomic32_dec(&s->num_mapped_cores); return ret; } @@ -446,7 +436,7 @@ service_runner_func(void *arg) if (!service_valid(i)) continue; /* return value ignored as no change to code flow */ - service_run(i, cs, service_mask, service_get(i)); + service_run(i, cs, service_mask, service_get(i), 1); } cs->loops++;