From patchwork Fri May 22 04:30:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Honnappa Nagarahalli X-Patchwork-Id: 187139 Delivered-To: patch@linaro.org Received: by 2002:a92:5b0a:0:0:0:0:0 with SMTP id p10csp2160485ilb; Thu, 21 May 2020 21:30:25 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyv3CUYWQpH9WXffX9DgsQ2pBN0AEtwSBIMGcxLhrnSPrg2gHs+E+u59tzxdnxhNzfnD+bS X-Received: by 2002:adf:f3cc:: with SMTP id g12mr1479949wrp.427.1590121825198; Thu, 21 May 2020 21:30:25 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1590121825; cv=none; d=google.com; s=arc-20160816; b=eIDVArHwPUdoqiKgpiZ8sDhsHWrgnQgdo9L9Obs3iHtXHtg6OE1sMEVge63I0HoWMd NiR8ZXpfRLp1giknn8Ex0OCow89ARZiekM75gbCmC7YBiMSVS484gl6c2Dj/ZNlyvS9f XaKT0PTopiS3urvnxM63QqjyftV4W4JwRvakStMU1I32Si/2GpclLRX989mLoFy0NyQ2 AYr9H2FlEVPYAH9VYRPpzrm4q2BcKxbjPKZlxDXfOOArqLqZPoBitMlkVrXszEgOJAsy PyFaxVI9o4gW9RfpYUAhpVJfoFq5YDLfIxfcIsIRxAFNhMcsKeOUfsRW0x/5vrq7teHN RIWQ== 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=WigIZO+cEbpaPj8zvbwToTcH21HRBCEQ/tmxzLhXHSQ=; b=dnVCpmlDEnU5mFIni7BVe3vDL1xstnu2910iJ1qE0vexadjC2eL57NBRoqX12//+eT AwAszJbRMf3zI111x39mLSWx4b85E6ARl5lR506PTgPiq/Jxgk35dnBjojbV5oZpMb7q VO4oQTv2KcZo9AMRTN13ERZ7BsnF/Mh+F1/0PqNsw6QRwlf17BD5qTWyXLRzNhIUb9JA 6sHF/4ZRSKKNoPJepTJH7MKek/u1fTlOptUtp4QIXHkUXH7qiMJMTjyxMeglz9+YatYS gw0kJPyCW7yOU/ANOW1uEojZ8nnHUERXTdCDogZCchOAtJQF8xIh0m+4XQEeZGlUxCp2 p8Ig== 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 m9si6833056wmg.214.2020.05.21.21.30.24; Thu, 21 May 2020 21:30:25 -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 E87491D8D8; Fri, 22 May 2020 06:30:23 +0200 (CEST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by dpdk.org (Postfix) with ESMTP id BF6941D73C for ; Fri, 22 May 2020 06:30:21 +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 0633231B; Thu, 21 May 2020 21:30:21 -0700 (PDT) Received: from qc2400f-1.austin.arm.com (qc2400f-1.austin.arm.com [10.118.14.48]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E4DC33F305; Thu, 21 May 2020 21:30:20 -0700 (PDT) From: Honnappa Nagarahalli To: dev@dpdk.org, konstantin.ananyev@intel.com, stephen@networkplumber.org, jerinj@marvell.com, hemant.agrawal@nxp.com Cc: ruifeng.wang@arm.com, phil.yang@arm.com, honnappa.nagarahalli@arm.com, nd@arm.com Date: Thu, 21 May 2020 23:30:13 -0500 Message-Id: <20200522043013.12535-1-honnappa.nagarahalli@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <1588835193-27550-1-git-send-email-phil.yang@arm.com> References: <1588835193-27550-1-git-send-email-phil.yang@arm.com> Subject: [dpdk-dev] [PATCH v2] doc: announce adoption of C11 atomic operations semantics 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" As agreed in the DPDK tech board [1], after 20.05 release, patches must use C11 atomic operations semantics with the help of wrappers. [1] http://mails.dpdk.org/archives/dev/2020-April/165143.html Signed-off-by: Honnappa Nagarahalli Reviewed-by: Phil Yang Reviewed-by: Ruifeng Wang Acked-by: Hemant Agrawal Acked-by: Jerin Jacob --- doc/guides/rel_notes/deprecation.rst | 13 +++++++++++++ 1 file changed, 13 insertions(+) -- 2.17.1 Acked-by: Konstantin Ananyev Acked-by: David Christensen diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst index 20aa745b7..01f99a0d6 100644 --- a/doc/guides/rel_notes/deprecation.rst +++ b/doc/guides/rel_notes/deprecation.rst @@ -113,3 +113,16 @@ Deprecation Notices Python 2 support will be completely removed in 20.11. In 20.08, explicit deprecation warnings will be displayed when running scripts with Python 2. + +* rte_atomicNN_xxx: These APIs do not take memory order parameter. This does + not allow for writing optimized code for all the CPU architectures supported + in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers + using C11 atomic built-ins. These wrappers must be used for patches that + need to be merged in 20.08 onwards. This change will not introduce any + performance degradation. + +* rte_smp_*mb: These APIs provide full barrier functionality. However, many + use cases do not require full barriers. To support such use cases, DPDK will + adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins. + These wrappers must be used for patches that need to be merged in 20.08 + onwards. This change will not introduce any performance degradation.