From patchwork Thu Mar 12 07:44:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Yang X-Patchwork-Id: 184434 Delivered-To: patch@linaro.org Received: by 2002:a92:1f12:0:0:0:0:0 with SMTP id i18csp232230ile; Thu, 12 Mar 2020 00:47:15 -0700 (PDT) X-Google-Smtp-Source: ADFU+vtslD/yrHopz1apsrixYA/vra+cDhGvKpUYxT1+VDiByB5XTfrU82cS0/XWPlag1S6Xl8KT X-Received: by 2002:a17:906:1108:: with SMTP id h8mr5842795eja.178.1583999235247; Thu, 12 Mar 2020 00:47:15 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1583999235; cv=none; d=google.com; s=arc-20160816; b=nrnR2FEF4HGMKrx64+TfIq5dpDSRe4koUC5wj/ox6hG2AavnNAOYoBx0nxVBO5REVm 3Xl2DGn7QAb2QKGWtFRHwixf3YzoEgUVzOnANDNtpGFXZVabEyS+miHFmHy4afXDXP/6 zTwFHLkOEhnO4ekCX4hwrvlnNuxhz/Y3fwc/AHQQg65wWOPNmvGhc+slC8MypM37wffg QD43Ozuqz48T4sB1RFs5coLS9PYsshn7CW5hT54rHGUHuFIj7meCwqNhjEHK9bY5GSUy 72hqohDI4wKDusd3V+sI2Uu6ZL7QA4opIDAuMbypDT+b7i1Df1QduWvGuAXa2NfgyhRA b7Ww== 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=A9saUY9jxsaWNPiTYtbeK59e82XEEk3N/P0FrHVjE78=; b=c9AvUnsE30CYU5iCuDoe/wMl/0boEiTSzUPMDMhnlCJnb7mmWd+2MCV+Pia+eNbzau vKULbrC4AFzFtfLgR64BT2h58kiTThMjx74xf13XNP+3YVXBHESn48Jazq7C2wl1tkq7 yaD/GJ5eNUY6rRwrvjfsRt1zv/Xe4lRVwAAHdekzWKQ3w5eKsQDu8R0ngOi4SH6y/VRC 5DT9qjGJty/rzvU8zx7tK6xFWm72WsLZJAwrgXRHLEYi82iKs4xmAUz101jDyVdFKRJX UWek1KawetKXGAWbirf7NrIML2mrWUyOwXJqH2ANNQFyet3xYZgJAXl+lWLrP4Weo6kQ dfNw== 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 dg5si2962701edb.44.2020.03.12.00.47.15; Thu, 12 Mar 2020 00:47:15 -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 0FB021C06D; Thu, 12 Mar 2020 08:46:04 +0100 (CET) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by dpdk.org (Postfix) with ESMTP id 90B101C0AE; Thu, 12 Mar 2020 08:46:02 +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 22978FEC; Thu, 12 Mar 2020 00:46:02 -0700 (PDT) Received: from phil-VirtualBox.shanghai.arm.com (phil-VirtualBox.shanghai.arm.com [10.169.109.150]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 092B53F534; Thu, 12 Mar 2020 00:45:57 -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: Thu, 12 Mar 2020 15:44:29 +0800 Message-Id: <1583999071-22872-9-git-send-email-phil.yang@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1583999071-22872-1-git-send-email-phil.yang@arm.com> References: <1583862551-2049-1-git-send-email-phil.yang@arm.com> <1583999071-22872-1-git-send-email-phil.yang@arm.com> Subject: [dpdk-dev] [PATCH v2 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 costlier than using atomic operations. Assume that the application passes the right parameters and reduces the number of instructions for all cases. Cc: stable@dpdk.org Signed-off-by: Honnappa Nagarahalli Reviewed-by: Phil Yang Reviewed-by: Gavin Hu --- 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..670f5a9 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 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++;