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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF00FC433E1 for ; Fri, 10 Jul 2020 08:30:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9D1A20842 for ; Fri, 10 Jul 2020 08:30:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gOS7slEj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727833AbgGJIaa (ORCPT ); Fri, 10 Jul 2020 04:30:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726921AbgGJIa3 (ORCPT ); Fri, 10 Jul 2020 04:30:29 -0400 Received: from mail-lj1-x242.google.com (mail-lj1-x242.google.com [IPv6:2a00:1450:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F632C08C5CE; Fri, 10 Jul 2020 01:30:29 -0700 (PDT) Received: by mail-lj1-x242.google.com with SMTP id s9so5471122ljm.11; Fri, 10 Jul 2020 01:30:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=mDEWF/gOHqnVFbtfXXs3ljAiSAYlhLzutQWngIQGuuA=; b=gOS7slEjmfSIMc70Zc4XyrJRIJM2oHl+hs03QvhWxULpvqVJRwvk+8TrRA6a3vCwqD DbzkKYHptOiixHhYHah4akFTFUzgKK/cjSeM0PDbl3yQ0KZ8xjvt5Wagm6mb27m/v/EG rRsnTdmxRbeG3kpNoeF5b53oEJpXDhJpUZJQmTOOYLx5Pk4GrnIQoKiIhX3PoWDndD6c y4M/J5bldXsB6uD2BkNgJgZun2FiluzeNRLyg7D+M2yWbCpy99AenMdqyoyrJnq+E7lg nKMc4FfS4GhtjeJBDu8QQ2KBB9v0eh6uGLktxEBwjwka6RawpQ/YKimwwvqRM0zzs8DT bWXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=mDEWF/gOHqnVFbtfXXs3ljAiSAYlhLzutQWngIQGuuA=; b=HV7MOc2LziQ80Cf72csrRckMsZHGDJHzPTVfbkkyZARlPV74/huXnj1slDuXfovuD5 +3LkBOittJT5qWRO4JyAJA/lZg7QJXHk3xbmv///GM94oiBOIFqEOMdF8B6cawtHwk4d W2J3iILB4Hgar+kG2lAho+2S7YyarmCIEcnMArWzCw+cGQuacPz4v7mGAYqrOA/YroMb BDR5Mbj2BhwJuY5cIN1LEKNjDtMd8TDIJ1TuOi4IclppOD7BQdynsQngLLAOFCnaeE9X vBesNX2HYf69DjrQBREj9q7TxsBscISoBGulmd7Q7qIY2UT1j0rPVeuSFtM48YGZeBnJ aFDw== X-Gm-Message-State: AOAM530cju8szFpK7DFzyVSSUI1LgWFOBTm1tAzpi9y3LpnQVJyRTQpN s6YSH3eyl2w6M5HTgk2CnVtzyYwW X-Google-Smtp-Source: ABdhPJyUbobhnRfuG8Q1eZvawPHgCwKO9ruGuN4OGU+5ociRzwSU/5mMHtbE8iYfIW16kZia9aABLg== X-Received: by 2002:a2e:9e89:: with SMTP id f9mr4747347ljk.212.1594369827440; Fri, 10 Jul 2020 01:30:27 -0700 (PDT) Received: from grain.localdomain ([5.18.102.224]) by smtp.gmail.com with ESMTPSA id 2sm1900072lfr.48.2020.07.10.01.30.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Jul 2020 01:30:26 -0700 (PDT) Received: by grain.localdomain (Postfix, from userid 1000) id E95A91A007B; Fri, 10 Jul 2020 11:30:25 +0300 (MSK) Date: Fri, 10 Jul 2020 11:30:25 +0300 From: Cyrill Gorcunov To: Rasmus Villemoes Cc: Andrew Morton , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] kcmp: add separate Kconfig symbol for kcmp syscall Message-ID: <20200710083025.GD1999@grain> References: <20200710075632.14661-1-linux@rasmusvillemoes.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200710075632.14661-1-linux@rasmusvillemoes.dk> User-Agent: Mutt/1.14.5 (2020-06-23) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 10, 2020 at 09:56:31AM +0200, Rasmus Villemoes wrote: > The ability to check open file descriptions for equality (without > resorting to unreliable fstat() and fcntl(F_GETFL) comparisons) can be > useful outside of the checkpoint/restore use case - for example, > systemd uses kcmp() to deduplicate the per-service file descriptor > store. > > Make it possible to have the kcmp() syscall without the full > CONFIG_CHECKPOINT_RESTORE. > > Signed-off-by: Rasmus Villemoes > --- > I deliberately drop the ifdef in the eventpoll.h header rather than > replace with KCMP_SYSCALL; it's harmless to declare a function that > isn't defined anywhere. Could you please point why setting #fidef KCMP_SYSCALL in eventpoll.h is not suitable? Still the overall idea is fine for me, thanks! Reviewed-by: Cyrill Gorcunov