From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27BAEC77B60 for ; Thu, 30 Mar 2023 17:52:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231929AbjC3RwF (ORCPT ); Thu, 30 Mar 2023 13:52:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229847AbjC3RwE (ORCPT ); Thu, 30 Mar 2023 13:52:04 -0400 Received: from mail-qv1-xf30.google.com (mail-qv1-xf30.google.com [IPv6:2607:f8b0:4864:20::f30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A223CDC8; Thu, 30 Mar 2023 10:52:03 -0700 (PDT) Received: by mail-qv1-xf30.google.com with SMTP id x8so14622239qvr.9; Thu, 30 Mar 2023 10:52:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1680198723; x=1682790723; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=4IR9SAM3kCBb7sI+E1m5cavLGwgTgCiGLAf0/i0xTGs=; b=o7CzjEeQkNqDVNYK9ZnwI2yCezVyErPe1bfsZYKe324dISFuAjnC9kXBtg1xMLfdbf 5eIhKSt8RhpS0p4Ik5nSvdwuQQ2J5AZAqXsFhSzgtDm/CUBlq6rUQnGdtkPiXQ908d0g JrNT4/HXtOupKtl4CcG91+u6pcUNImv8gngeCfB76s9stPqOejEnl87S90EWoaHtQ08J +e9ZsfIt1JjLI+oFXe58W1NSYR1RkrWd8GsGchwWZHisJS1jUPWAgg+ftSMt7pUmXoVf I92ZsAVjDQYvANzw1rk3HXfZL+erRw9vAj2mTQF4A/31YdbXsyZuh4MaMQGXP+16MSvy OB9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680198723; x=1682790723; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=4IR9SAM3kCBb7sI+E1m5cavLGwgTgCiGLAf0/i0xTGs=; b=SqMT8JtQjLtZugviocfMDZ1EFV7L2raqHODJKipib8sK+fx3XirvKPjspr+K6yDX6c f1wJYcGu+/FRH00mHH6HRIH/qy4e0zhSupCPIIpiIhPML6qAXwuyqZYIJNACBCYBAwvm 33KcYaQDjOkKqtT/YPM8NbhHryFpxVrwhN++LE9qIzp/OkuGnz0CoA8Az0J8DMiHdwNq Oe4sUPtNZ6qFtbuQSF+s/EfOWa7BDEQPIA4k2V3U71uldVcchIfLvRJdXsOaZ6RvZbIA c/xJMrYj2QOr3n4vf1NWO1xNGjk0sg/C9qBJgoks/wWpLXEaH66g1iQ/EYWvuBumL+oG rQng== X-Gm-Message-State: AAQBX9fEswe1VX0p3o48zHEWN1hbsxg/EJ6jg2r5eAUf50IF9VU8P2Fl ei3p3vCBHnl/h2AnjbmtbbQ= X-Google-Smtp-Source: AKy350Z8Mtc2vYf4x+x2ABACFrvEg6sLt6QSC1cYwtcxUxIYKqmd/KO0J/rRV8HKQmERsmUh/XLC0w== X-Received: by 2002:a05:6214:b64:b0:5b8:1f61:a20 with SMTP id ey4-20020a0562140b6400b005b81f610a20mr45046940qvb.35.1680198722777; Thu, 30 Mar 2023 10:52:02 -0700 (PDT) Received: from localhost (240.157.150.34.bc.googleusercontent.com. [34.150.157.240]) by smtp.gmail.com with ESMTPSA id z6-20020a0cfec6000000b005dd8b9345a0sm5617916qvs.56.2023.03.30.10.51.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Mar 2023 10:51:57 -0700 (PDT) Date: Thu, 30 Mar 2023 13:51:56 -0400 From: Willem de Bruijn To: David Howells , Willem de Bruijn Cc: dhowells@redhat.com, Matthew Wilcox , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Al Viro , Christoph Hellwig , Jens Axboe , Jeff Layton , Christian Brauner , Chuck Lever III , Linus Torvalds , netdev@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Message-ID: <6425cc3c9d750_21f56920832@willemb.c.googlers.com.notmuch> In-Reply-To: <854582.1680188845@warthog.procyon.org.uk> References: <64259c7b2b327_21883920818@willemb.c.googlers.com.notmuch> <20230329141354.516864-1-dhowells@redhat.com> <20230329141354.516864-5-dhowells@redhat.com> <854582.1680188845@warthog.procyon.org.uk> Subject: Re: [RFC PATCH v2 04/48] net: Declare MSG_SPLICE_PAGES internal sendmsg() flag Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org David Howells wrote: > Willem de Bruijn wrote: > > > No need to modify __sys_sendmmsg explicitly, as it ends up calling > > __sys_sendmsg? > > > > Also, sendpage does this flags masking in the internal sock_FUNC > > helpers rather than __sys_FUNC. Might be preferable. > > I was wondering whether other flags, such as MSG_BATCH should be added to the > list. Is it bad if userspace sets that in sendmsg()? AF_KCM, at least, looks > at it. That flag was added exactly for AF_KCM. A process that explicitly sets it might experience bad behavior (increased latency), but there are no legacy AF_KCM applications that precede the flag.