From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 9D81B42B8C; Wed, 24 May 2023 14:52:09 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id B7AF1410F9; Wed, 24 May 2023 14:52:08 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id D819D40ED5 for ; Wed, 24 May 2023 14:52:04 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684932724; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=K6bBh5gsBuHMJRYf2/g6gGuHlTyUgHe53SUet9TdH9Q=; b=WCtjaMqRF9OiChPIc3PNf9V1UBW4yaiGW4HhYN9XAL6PlOv0MHo2Jx9bcmsfnXgWEefO7a DtvE/EZ+SdwNN9IjMW742o3ysgQaUjz2Bluj5FFxj0HEVnHzuuAr0sO9sXiJ6yYiN3YjVZ ul7UbqeH7Rtaxxp3fCgGwbDrfx0WSf0= Received: from mail-pg1-f198.google.com (mail-pg1-f198.google.com [209.85.215.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-328-k2Kps_VXPaSEQBKKZMMQMg-1; Wed, 24 May 2023 08:52:03 -0400 X-MC-Unique: k2Kps_VXPaSEQBKKZMMQMg-1 Received: by mail-pg1-f198.google.com with SMTP id 41be03b00d2f7-53ba38cf091so120765a12.1 for ; Wed, 24 May 2023 05:52:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684932722; x=1687524722; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=K6bBh5gsBuHMJRYf2/g6gGuHlTyUgHe53SUet9TdH9Q=; b=GTCJVK7KlPPyaqdql2hwM2uDjXCDAdd1CekWi3yHpdbLB7qVpWTV+thmMKNVOTcz7B yuB4wToSuOEaTchXSxKTF20gb2cOUK89aKztDaMIHWGLFsKrmPNuTbPIQhFBB8qQ3xsX hXzLHNwgGAfjj1RY+0k19Yh9jvxVMYinAnki/N4Oj52di1nqAr2KDONlP14fP06yVUfe M6qzoFzQwo/bPWQ/xZh/UCjjRrmAt3q0OIMdy2mnZLxpG+Wr/eZBd6SvJS9U15IG8cZk c8hLdJArNOj1h+CfMXTEgOTUaA1VapzYz1YmGAxg/u68hGKxI7baDnDTn9zY0SRV9Ibg fMdg== X-Gm-Message-State: AC+VfDxlVxGfiHF7LTk5UyJNicR/QX86WnSI3vWwXyyb0/lLlYYM8Qex SKSW9gyeIvL47ZMHa40FQTjrdXvW/xtglfPEGaKiPQigW66jHp235B3WFspsJCkUyevzc38U4zg rMHgpLUhYRkMWjEAvXm8= X-Received: by 2002:a17:902:ecc6:b0:1af:ea40:34f2 with SMTP id a6-20020a170902ecc600b001afea4034f2mr427575plh.11.1684932722251; Wed, 24 May 2023 05:52:02 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ4SafIgrxivQcivoxgsPkl5yINNP6WAKlQnasNyclZ9ZiGIm3cgj3YlCb1IA4OwDgHSTH42Wxo9ghziQHQR7j4= X-Received: by 2002:a17:902:ecc6:b0:1af:ea40:34f2 with SMTP id a6-20020a170902ecc600b001afea4034f2mr427562plh.11.1684932721975; Wed, 24 May 2023 05:52:01 -0700 (PDT) MIME-Version: 1.0 References: <1679927420-26737-1-git-send-email-roretzla@linux.microsoft.com> In-Reply-To: <1679927420-26737-1-git-send-email-roretzla@linux.microsoft.com> From: David Marchand Date: Wed, 24 May 2023 14:51:50 +0200 Message-ID: Subject: Re: [PATCH 0/3] use C11 memory model GCC builtin atomics To: Tyler Retzlaff Cc: dev@dpdk.org, Honnappa.Nagarahalli@arm.com, Ruifeng.Wang@arm.com, thomas@monjalon.net, Maxime Coquelin X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Mon, Mar 27, 2023 at 4:30=E2=80=AFPM Tyler Retzlaff wrote: > > Replace the use of __sync__and_fetch and __sync_fetch_and_ atomic= s > with GCC C11 memory model __atomic builtins. > > This series contributes to converging on standard atomics in 23.11 but is > kept separate as there may be sensitivity to converting from __sync to th= e > C11 memory model builtins. - Looking at the patches, I thought the conversion was rather straightforwa= rd. But this mention about "sensitivity" stopped me from merging. Did I miss some risk with the changes of this series? > > Tyler Retzlaff (3): > bus/vmbus: use C11 memory model GCC builtin atomics > crypto/ccp: use C11 memory model GCC builtin atomics > eal: use C11 memory model GCC builtin atomics > > drivers/bus/vmbus/vmbus_channel.c | 2 +- > drivers/crypto/ccp/ccp_dev.c | 6 ++++-- > lib/eal/include/generic/rte_atomic.h | 32 ++++++++++++++++--------------= -- > 3 files changed, 21 insertions(+), 19 deletions(-) - I noticed that the vhost library has been providing an internal wrapper for some __sync atomic with older GCC. Some details are in the commitlog c16915b87109 ("vhost: improve dirty pages logging performance"). Could it affect the existing legacy API performance? --=20 David Marchand