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=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 6AE69C433DF for ; Fri, 16 Oct 2020 18:24:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 14536208E4 for ; Fri, 16 Oct 2020 18:24:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602872666; bh=f15X117SKzpCNYVRnL/Vou/NX2fSUVVJGrzQjomosRM=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=mmJR2s8E4X4gECjpCfw/ibR8YRRbLFLKKq+/tw4fQtHB4qBogP+iesblF2btI+6Yb mZcMHQ54QuLQ9sHQNKKcLH3zaV92fMH74aBIWVIapOtD0eHvMSRiYzamugiUG0qkDH hSiTB8l9i8H17qf11m9slUNAWu9E7s5Dj/oiyjW0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391626AbgJPSYZ (ORCPT ); Fri, 16 Oct 2020 14:24:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391390AbgJPSYZ (ORCPT ); Fri, 16 Oct 2020 14:24:25 -0400 Received: from mail-lj1-x243.google.com (mail-lj1-x243.google.com [IPv6:2a00:1450:4864:20::243]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0974EC061755 for ; Fri, 16 Oct 2020 11:24:25 -0700 (PDT) Received: by mail-lj1-x243.google.com with SMTP id c21so3472319ljn.13 for ; Fri, 16 Oct 2020 11:24:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6eKAiz03REd9F2BGqg3XB1WUDmxvOSQH4Qk1B3giWI8=; b=HOlq+tisLvBTlTkFI/Z1ZSYH9Wc7UVWpNJU7I96TvJHnJe60SklqXQXpuap3g3Wr6t /fhT2idAFuMGsWtDh3IH2dl1NZH9H6o+MX8J2YDyMyV5Ld28VbG1rw+ZZdOWX5M2VPVN mVK3DM8QqneboyILTGgxDOv71Bcc70VPxXjl8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=6eKAiz03REd9F2BGqg3XB1WUDmxvOSQH4Qk1B3giWI8=; b=H6SxjlH1hNUT4nWhOXmLMJWRRRJQCBzGYB1Pb53ePgCT3nhiLEhEPRigEWqp8sYOOk S2pSPbgs+tSjuJL2BOjzcWj5exQQssXwblTdk3ln58b1n2YtyQtYDPPb5MLQMXLulwGM 81LO/Bnfm2AjW1O3Wn9W7kAnSUnTaJ8EQtm3Szejg03ftpRhiI4o1tOaL6kCDkzimI3J 3PsC8/yGMTK5lYKO1mnUtMl1U5bRklP48hAjSLrlLcJuj5tnvPbovTW6EHlCBXA6NZZN kBWznkrxnTJVdkPtZzIPYfIEwp20G//ThQXRYJbBb1DCI9EBt5oJ2tDlT/mcpoHKET08 JA1Q== X-Gm-Message-State: AOAM533WZgUI5z87sS3xiQBKDMz8eDpQqNfjO64hnW0rDY5I7rw1ABWA iJFpwhWgU0sfoHXWPGL+STER+PqgEVRl3w== X-Google-Smtp-Source: ABdhPJwIurFOfuxIuGiM0YPh+8196ahQjaIE/JoHn1F+ah92F8dkODL4xgxTRD+rKCqZknzmveGc3w== X-Received: by 2002:a2e:8757:: with SMTP id q23mr2101244ljj.82.1602872663197; Fri, 16 Oct 2020 11:24:23 -0700 (PDT) Received: from mail-lf1-f52.google.com (mail-lf1-f52.google.com. [209.85.167.52]) by smtp.gmail.com with ESMTPSA id r2sm1134118ljd.20.2020.10.16.11.24.18 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Oct 2020 11:24:19 -0700 (PDT) Received: by mail-lf1-f52.google.com with SMTP id v6so4091792lfa.13 for ; Fri, 16 Oct 2020 11:24:18 -0700 (PDT) X-Received: by 2002:a19:cbcb:: with SMTP id b194mr2024112lfg.133.1602872658198; Fri, 16 Oct 2020 11:24:18 -0700 (PDT) MIME-Version: 1.0 References: <4794a3fa3742a5e84fb0f934944204b55730829b.camel@lca.pw> <20201015151606.GA226448@redhat.com> <20201015195526.GC226448@redhat.com> <20201016181908.GA282856@redhat.com> In-Reply-To: <20201016181908.GA282856@redhat.com> From: Linus Torvalds Date: Fri, 16 Oct 2020 11:24:02 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Possible deadlock in fuse write path (Was: Re: [PATCH 0/4] Some more lock_page work..) To: Vivek Goyal Cc: Miklos Szeredi , Qian Cai , Hugh Dickins , Matthew Wilcox , "Kirill A . Shutemov" , Linux-MM , Andrew Morton , linux-fsdevel , Amir Goldstein Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Oct 16, 2020 at 11:19 AM Vivek Goyal wrote: > > So with multi page writes performance seems much better for this > particular workload. Looking at that code, I don't see why the page needs to be unlocked after it's been filled, so I do think the easy solution is to just always unlock the pages. Then the rest of the multi-page code is probably fine. But hey, who knows. I might be missing something. Linus