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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 002D2C433DF for ; Wed, 24 Jun 2020 06:37:49 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C2A7C207DD for ; Wed, 24 Jun 2020 06:37:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="QWjC9cDt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2A7C207DD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KfiFEn9B3632cx1qDP8jvtyjj25r5HHjy8Vjb1twUyE=; b=QWjC9cDtF76YjEgU/tVQmHmqs 6nRUwbG0yUweIZSyOTluH51+sYIwG6NTBdTQnEnG72SHevmPSrEZQEqeFnt1Tcxq5lSUdeGQjH0vX PTdu914RdXFeVB1MC5gqwQe+v/YuuquyyK266FoLp5Ekyv6zcI2VLVB+WhlheZMCMpWr4X2V87aMK GEG4+CteMh1c5iB0Uwdu9FPzC7XKuE5PxuGvnqRut3NDY6qcAGbVzK1sNrLFta16yPrHFHZTzTmkL iR1A5dhhbwH+epoc8xAZV/lnU8P8csXh8kaiuwsJHjjtNucWyKhOSFyrTj9rPJEy8ltI49OoDI+G9 ZSMtdyyAg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jnz2Z-0000O3-5o; Wed, 24 Jun 2020 06:37:47 +0000 Received: from verein.lst.de ([213.95.11.211]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jnz2A-0000JD-Gh for linux-nvme@lists.infradead.org; Wed, 24 Jun 2020 06:37:23 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 0A02368AEF; Wed, 24 Jun 2020 08:37:20 +0200 (CEST) Date: Wed, 24 Jun 2020 08:37:19 +0200 From: Christoph Hellwig To: Sagi Grimberg Subject: Re: [PATCH v2 for-5.8-rc 3/6] nvme: don't protect ns mutation with ns->head->lock Message-ID: <20200624063719.GC17594@lst.de> References: <20200624001853.5408-1-sagi@grimberg.me> <20200624001853.5408-4-sagi@grimberg.me> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200624001853.5408-4-sagi@grimberg.me> User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Busch , Anton Eidelman , Christoph Hellwig , linux-nvme@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Jun 23, 2020 at 05:18:50PM -0700, Sagi Grimberg wrote: > Right now ns->head->lock is protecting namespace mutation > which is wrong and unneeded. Move it to only protect > against head mutations. While we're at it, remove unnecessary > ns->head reference as we already have head pointer. The changes look reasonable (nitpick below), but this changelog doesn't sway what the problem is and how it it fixed. > - synchronize_srcu(&ns->head->srcu); > - kblockd_schedule_work(&ns->head->requeue_work); > + synchronize_srcu(&head->srcu); > + kblockd_schedule_work(&head->requeue_work); > + mutex_unlock(&head->lock); Can't we move the synchronize_srcu and kblockd_schedule_work out of the lock as well? _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme