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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 4964CC433E0 for ; Tue, 9 Jun 2020 10:20:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1C4AC2083E for ; Tue, 9 Jun 2020 10:20:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="b9FcJ+mn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728633AbgFIKUZ (ORCPT ); Tue, 9 Jun 2020 06:20:25 -0400 Received: from mail.skyhub.de ([5.9.137.197]:38358 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727831AbgFIKUZ (ORCPT ); Tue, 9 Jun 2020 06:20:25 -0400 Received: from zn.tnic (p200300ec2f0d68002503c5de6f6b5eb0.dip0.t-ipconnect.de [IPv6:2003:ec:2f0d:6800:2503:c5de:6f6b:5eb0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 21B641EC02B1; Tue, 9 Jun 2020 12:20:23 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1591698023; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=085VCpEjqM+GYch4ms9evINYEp+0wAs7XM3mVBlU0S0=; b=b9FcJ+mnX+Q47LOFSNU9YDy/3dRiU1w3RBY8bgcoCgkrdaRNbP/GouFz6vOgiKtrl38pMx pV/jHoN7mWdbF16dfS5hAMKtsgLyxySnBkwXlmpPdpcPEzMK9EfNi7taapklf49q2HZui9 dcztIqPhrt6fhELlQj9WfKpK6elI13Q= Date: Tue, 9 Jun 2020 12:20:15 +0200 From: Borislav Petkov To: Ritesh Harjani Cc: Marek Szyprowski , Ritesh Harjani , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jan Kara , Theodore Ts'o , "Aneesh Kumar K . V" , linux-kernel@vger.kernel.org Subject: Re: [PATCHv5 3/5] ext4: mballoc: Introduce pcpu seqcnt for freeing PA to improve ENOSPC handling Message-ID: <20200609102015.GA7696@zn.tnic> References: <7f254686903b87c419d798742fd9a1be34f0657b.1589955723.git.riteshh@linux.ibm.com> <2940d744-3f6f-d0b5-ad8d-e80128c495d0@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <2940d744-3f6f-d0b5-ad8d-e80128c495d0@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, Jun 03, 2020 at 03:40:16PM +0530, Ritesh Harjani wrote: > Yes, this is being discussed in the community. > I have submitted a patch which should help fix this warning msg. > Feel free to give this a try on your setup. > > https://marc.info/?l=linux-ext4&m=159110574414645&w=2 I just triggered the same thing here too. Looking at your fix and not even pretending to know what's going on with that percpu sequence counting, I can't help but wonder why do you wanna do: seq = *raw_cpu_ptr(&discard_pa_seq); instead of simply doing: seq = this_cpu_read(discard_pa_seq); ? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette