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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 79DD8C0044D for ; Thu, 12 Mar 2020 02:29:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 65A9E20754 for ; Thu, 12 Mar 2020 02:29:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="HIShHKke" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65A9E20754 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 785906B0003; Wed, 11 Mar 2020 22:29:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 736B76B0006; Wed, 11 Mar 2020 22:29:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 64CBF6B0007; Wed, 11 Mar 2020 22:29:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0108.hostedemail.com [216.40.44.108]) by kanga.kvack.org (Postfix) with ESMTP id 49B8F6B0003 for ; Wed, 11 Mar 2020 22:29:55 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 18920180EE412 for ; Thu, 12 Mar 2020 02:29:55 +0000 (UTC) X-FDA: 76585129950.21.soda14_1c590fdd8015b X-HE-Tag: soda14_1c590fdd8015b X-Filterd-Recvd-Size: 2191 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Thu, 12 Mar 2020 02:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=1Jj6L8vIcZ93mZ6eanG7loVD291lPrGo+W34O45vAww=; b=HIShHKkeQH+3yNOsaYMjZBAn0o LxgYzRbK8kN8tAOUHcRHX18tSVWlTb9yexsxk+5sDZic+MpENzPUMWEFl6V9UvvkEp3W+7AcVF4w+ /g1YlvOU/R+R594ghg5lUax6xjXiX5FsG4j0slA/7V7o2Xkyt8vrcjuG/PVZSTaQ4qWiH5qYgen2+ VgjPRy36KC55yPk5/d2IO89IvCf/1j7Ao9o/OPxwvZBOjS636jziQ3KRGgBjLfxCgHrV++XGKGbHP uSD4Qe+ER5RmV1cKeWvM9ink9+Pj2V86+AwKqcvP7QgXK6UJhuxpyR1ej5QiSoELlwlF2JlDLPBOF jkDrc7eg==; Received: from willy by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jCDbZ-000361-13; Thu, 12 Mar 2020 02:29:49 +0000 Date: Wed, 11 Mar 2020 19:29:48 -0700 From: Matthew Wilcox To: Andrew Morton Cc: Jules Irenge , boqun.feng@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] backing-dev: refactor wb_congested_put() Message-ID: <20200312022948.GH22433@bombadil.infradead.org> References: <20200312002156.49023-1-jbi.octave@gmail.com> <20200312002156.49023-2-jbi.octave@gmail.com> <20200311175919.30523d55b2e5307ba22bbdc0@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200311175919.30523d55b2e5307ba22bbdc0@linux-foundation.org> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 11, 2020 at 05:59:19PM -0700, Andrew Morton wrote: > hm, it's hard to get excited over this. Open-coding the > refcount_dec_and_lock_irqsave() internals at a callsite in order to > make sparse happy. > > Is there some other way, using __acquires (for example)? sparse is really bad at conditional lock acquisition. we have similar problems over the vfs. but we shouldn't be obfuscating our code to make the tool happy.