From patchwork Tue Mar 17 01:17:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phil Yang X-Patchwork-Id: 184605 Delivered-To: patch@linaro.org Received: by 2002:a92:1f12:0:0:0:0:0 with SMTP id i18csp3500936ile; Mon, 16 Mar 2020 18:20:06 -0700 (PDT) X-Google-Smtp-Source: ADFU+vsj2QRNBhFpWtQFd9riRBfgTnXB6MJ+ui8A7ymcZxmj6e/m0P+rw8fmPUpp+rp/ggFMnum0 X-Received: by 2002:a05:600c:2297:: with SMTP id 23mr1849935wmf.135.1584408006248; Mon, 16 Mar 2020 18:20:06 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1584408006; cv=none; d=google.com; s=arc-20160816; b=EVvuOQt/tVcI10SV9djQzj4k9F1qV25Z8Kpwx5ooy5jBYyF/feeYTGYL3j+Nrttcwz bf893wLI4HUOW01iPQoh42z7Trykz4aZXZDygxI30xx1V3cIk0IegwY7W+oBFHWLOWHG aUy9teiG2uVWD9fsk6K/d5fFZIV3nC3OtdYTiU68bu7CANMoxv5/E8vF5ykpFIDk3kVU 2O4gEz3htY/9vmVh86eABb7+Od9qBsMKNwKrZBQblfVVfwvR4jNPtUjlPPwyWhxWW3Ju ciV7pYp4vAplgIu+YHpeC31uExblrT1sZOuydz/EVXM+ZkQpx+Qh6Mi6bLlI7hmzq7pr I6JQ== 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=6Il56caGsdXEQ6PGpKc91Jj+W5zndfhj1ImiM7XmJZY=; b=RNQMFhKC01aBEXAkCpetJ/61RE2Oxa7kdcDA7kOZGu55Pt67NtWEm8sH8OdFB/hwDj RUb+1HvPrgmL+sPToTDwuxPrdB578dwxDfNw2s8aIHU9/13Y2gG+5N9KN9QUkh4dsqpg T+2tapDtArx8FatnkpDGUUi9rVTdYaONahj90ZRa9k0x24De+QGLICl25XA3BPx3YXHE o9PsT8LlmpG3odgvap+z81jDtsm9Z5/4tY6bSbGOC6xCg9BqgR9M3hZ2Ni5JiSW+irQO gF6+7l+FshOLi10WjhFCkgW2GyZj0mXwjzI3YJ51r8su9Cjf8b/HuJqVQrGp44fErDIW rzKw== 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 t23si968295wmj.214.2020.03.16.18.20.06; Mon, 16 Mar 2020 18:20:06 -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 807D71C127; Tue, 17 Mar 2020 02:19:09 +0100 (CET) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by dpdk.org (Postfix) with ESMTP id A389A1C0B7; Tue, 17 Mar 2020 02:19:08 +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 2BC33FEC; Mon, 16 Mar 2020 18:19:08 -0700 (PDT) Received: from phil-VirtualBox.shanghai.arm.com (phil-VirtualBox.shanghai.arm.com [10.169.108.137]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DED1B3F52E; Mon, 16 Mar 2020 18:19:03 -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: Tue, 17 Mar 2020 09:17:41 +0800 Message-Id: <1584407863-774-11-git-send-email-phil.yang@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1584407863-774-1-git-send-email-phil.yang@arm.com> References: <1583999071-22872-1-git-send-email-phil.yang@arm.com> <1584407863-774-1-git-send-email-phil.yang@arm.com> Subject: [dpdk-dev] [PATCH v3 10/12] 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 32a2f8a..0843c3c 100644 --- a/lib/librte_eal/common/rte_service.c +++ b/lib/librte_eal/common/rte_service.c @@ -360,7 +360,7 @@ 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; @@ -374,7 +374,7 @@ 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; @@ -412,24 +412,14 @@ 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; } @@ -449,7 +439,7 @@ 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++;