From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 1770FA00C5; Mon, 6 Jul 2020 12:04:18 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id D401C1D8FB; Mon, 6 Jul 2020 12:04:17 +0200 (CEST) Received: from new4-smtp.messagingengine.com (new4-smtp.messagingengine.com [66.111.4.230]) by dpdk.org (Postfix) with ESMTP id 0CB391D704 for ; Mon, 6 Jul 2020 12:04:16 +0200 (CEST) Received: from compute7.internal (compute7.nyi.internal [10.202.2.47]) by mailnew.nyi.internal (Postfix) with ESMTP id 618DD580437; Mon, 6 Jul 2020 06:04:15 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute7.internal (MEProxy); Mon, 06 Jul 2020 06:04:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monjalon.net; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s=fm1; bh= B3GwkgzqKgCmFP1N6lNpiEuM4ufbulSNUSqCE/464Hk=; b=VInpwPt+nun14S6M v2PYVtvrJPqC/ZHcsASQf7d3bpCjah8NtqnnTCYlZxno2j45mCFS5hqOSLG6JUnR 0KqnEHQxUBlEFPUE+NT30NphDqJCiXHpFqA+4+pyAreMR6xG9Od31AAYer7I+Trz C/3MHOMad4cdezEe/T3kPM4VTR/RRtw0ArvLFU0hq9PXvEU8WTpho/7CzSTJwyPA XcG2HD1TJjOrWehhKlKwNug761PgZ2sEnHfwZgAvtcVql38/GyScUhbeo962iwiW wEAhAWLVkD0224CimHf0WRIiEPHirEB+so/Y/OKuiKcWleNwgNIwuB4wZg/dzKwn 0HJuXQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:in-reply-to:message-id:mime-version:references :subject:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; bh=B3GwkgzqKgCmFP1N6lNpiEuM4ufbulSNUSqCE/464 Hk=; b=Pm8s5XD7f75IrzYYH/6f+dtWn9YYq2bPIwsVnh0oZ1e8md02oUnOxLoO8 QexA5K1wom6qD5YeDic9hzhPGC71Q1wdjOGUUq7Cn9yszj94wl/h27qIW0XebWkX xtphbtttTcWdV8c9qnEGq5vva8AryICq4wnQyT2+5EvrUvdnpRIv+oixwGvnGp++ 02GQplE+bFQMPoii/IOuP8qBvCJkAZU+MGgkktQc8cIVu+XxV9TV2q/6KfN0V01g KcCuISVYuXWiWCzxNUcjX4N9wFURvvfXBVpmN0dcBQCyPGc/24PzyM/FO7zY7KUl A5hSPZjms2jO5vg9uP4FQXvQcYOvg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduiedrudefgddvfecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkjghfggfgtgesthfuredttddtvdenucfhrhhomhepvfhhohhmrghs ucfoohhnjhgrlhhonhcuoehthhhomhgrshesmhhonhhjrghlohhnrdhnvghtqeenucggtf frrghtthgvrhhnpeffvdffjeeuteelfeeileduudeugfetjeelveefkeejfeeigeehteff vdekfeegudenucffohhmrghinhepughpughkrdhorhhgnecukfhppeejjedrudefgedrvd dtfedrudekgeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhr ohhmpehthhhomhgrshesmhhonhhjrghlohhnrdhnvght X-ME-Proxy: Received: from xps.localnet (184.203.134.77.rev.sfr.net [77.134.203.184]) by mail.messagingengine.com (Postfix) with ESMTPA id 1376E328005A; Mon, 6 Jul 2020 06:04:11 -0400 (EDT) From: Thomas Monjalon To: Phil Yang Cc: erik.g.carrillo@intel.com, dev@dpdk.org, jerinj@marvell.com, Honnappa.Nagarahalli@arm.com, drc@linux.vnet.ibm.com, Ruifeng.Wang@arm.com, Dharmik.Thakkar@arm.com, nd@arm.com, david.marchand@redhat.com, mdr@ashroe.eu, Neil Horman , Dodji Seketeli Date: Mon, 06 Jul 2020 12:04:10 +0200 Message-ID: <3726677.YG9GXOvrMZ@thomas> In-Reply-To: <1593667604-12029-4-git-send-email-phil.yang@arm.com> References: <1591960798-24024-1-git-send-email-phil.yang@arm.com> <1593667604-12029-1-git-send-email-phil.yang@arm.com> <1593667604-12029-4-git-send-email-phil.yang@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Subject: Re: [dpdk-dev] [PATCH v2 4/4] eventdev: relax smp barriers with c11 atomics 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" 02/07/2020 07:26, Phil Yang: > The implementation-specific opaque data is shared between arm and cancel > operations. The state flag acts as a guard variable to make sure the > update of opaque data is synchronized. This patch uses c11 atomics with > explicit one way memory barrier instead of full barriers rte_smp_w/rmb() > to synchronize the opaque data between timer arm and cancel threads. I think we should write C11 (uppercase). Please, in your explanations, try to be more specific. Naming fields may help to make things clear. [...] > --- a/lib/librte_eventdev/rte_event_timer_adapter.h > +++ b/lib/librte_eventdev/rte_event_timer_adapter.h > @@ -467,7 +467,7 @@ struct rte_event_timer { > * - op: RTE_EVENT_OP_NEW > * - event_type: RTE_EVENT_TYPE_TIMER > */ > - volatile enum rte_event_timer_state state; > + enum rte_event_timer_state state; > /**< State of the event timer. */ Why do you remove the volatile keyword? It is not explained in the commit log. This change is triggering a warning in the ABI check: http://mails.dpdk.org/archives/test-report/2020-July/140440.html Moving from volatile to non-volatile is probably not an issue. I expect the code generated for the volatile case to work the same in non-volatile case. Do you confirm? In any case, we need an explanation and an ABI check exception.