From patchwork Mon Mar 9 07:05:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: harshad shirwadkar X-Patchwork-Id: 1251243 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-ext4-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=Xjai41r2; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48bTlb6VLQz9sRR for ; Mon, 9 Mar 2020 18:06:03 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726467AbgCIHGD (ORCPT ); Mon, 9 Mar 2020 03:06:03 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:34627 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726215AbgCIHGC (ORCPT ); Mon, 9 Mar 2020 03:06:02 -0400 Received: by mail-pf1-f194.google.com with SMTP id 23so2608945pfj.1 for ; Mon, 09 Mar 2020 00:06:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=fSUx91OCD79MSnLeeD7t851nsccIfmuWdICD8nRJqeg=; b=Xjai41r2aioj99tgmKs/f6ipRy+dr+gv9rBAYSOoXY8/aAlDQCNcck09g659rRtsij /dEbq81iP0h34nO2cvbJGgoIv5FA5fP4WFjGv1Xa4yfIYOZgbFSm5YLCEQtsCbEH64d2 NKHc7MOtst33qT31aWn0mhwdUTY1Fhn4iuXrvBQwYxODKTS3r1ezvkrhCZPijNs2BR9g J4OMSKLrVzb0RfFXnEoOhq2zhARtZDghJ9w8jFE451AOMWhS/e7gZGq+Hi0S15ptw/QU imCgjJE4ReTqFXjdjgfVYG37TFTWv8QmnOH/GR/lPtM7/QkhBTm0H7ZCBgmGefl9w2V4 AcdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=fSUx91OCD79MSnLeeD7t851nsccIfmuWdICD8nRJqeg=; b=QBQBPxuoKPBfEIHtKeQ5fWLXlF4lJrpIaQzwyT5JRPx0DiJC1U7BWmwXVJVePSMLIB Bm/M34DAiCOqwABjVeUOmUwyamqvO/Kc+5xDn+Llc9qQrACe0kWa5QinbawIFL3NVM5+ 3/zMWj0jzZevfTdk4QRySjl0CiGcOAUh+nFRKvvGuZYSEpGHJsBUxLcK75pRaEJjz+3p woddhtQ49hBBAO3fRiyEUGX+pnkZ60tWVpQneniIDFC2u7BKxnx+Eord34lAC6YAMDqy t5j/DRiEEtXv1T14kUL7J3+674qneihKDNSzdOqSkHf2hrtrS8J9O+RgTiMJ4GXDw51m +IBw== X-Gm-Message-State: ANhLgQ0mka21RtnULO5ZwtXaN2fNIVGGYA7Fc4EIXH5OWCIrP9gSYdtN HmctLVwj6Pbe6eORYISU6QS90gqv X-Google-Smtp-Source: ADFU+vtDzSioea9Q7LYZ7/KMCgZ+quBImkSu6QKtUlFJVMO0oNrbHOXo+LOwSZlAHyqhaRIRjfcfKw== X-Received: by 2002:a62:820e:: with SMTP id w14mr16239923pfd.59.1583737559699; Mon, 09 Mar 2020 00:05:59 -0700 (PDT) Received: from harshads0.svl.corp.google.com ([2620:15c:2cd:202:ec1e:207a:e951:9a5b]) by smtp.googlemail.com with ESMTPSA id 8sm3692593pfp.67.2020.03.09.00.05.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Mar 2020 00:05:59 -0700 (PDT) From: Harshad Shirwadkar To: linux-ext4@vger.kernel.org Cc: Harshad Shirwadkar Subject: [PATCH v5 05/20] jbd2: disable fast commits if journal is empty Date: Mon, 9 Mar 2020 00:05:11 -0700 Message-Id: <20200309070526.218202-5-harshadshirwadkar@gmail.com> X-Mailer: git-send-email 2.25.1.481.gfbce0eb801-goog In-Reply-To: <20200309070526.218202-1-harshadshirwadkar@gmail.com> References: <20200309070526.218202-1-harshadshirwadkar@gmail.com> MIME-Version: 1.0 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org If journal is empty, clear the fast commit flag from the on disk superblock. With this optimization, chances of running into backward compatibility issues are reduced. Signed-off-by: Harshad Shirwadkar --- fs/jbd2/journal.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 79f015f7bf54..f8f55d0814ea 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -1482,6 +1482,7 @@ int jbd2_journal_update_sb_log_tail(journal_t *journal, tid_t tail_tid, static void jbd2_mark_journal_empty(journal_t *journal, int write_op) { journal_superblock_t *sb = journal->j_superblock; + bool had_fast_commit = false; BUG_ON(!mutex_is_locked(&journal->j_checkpoint_mutex)); lock_buffer(journal->j_sb_buffer); @@ -1495,9 +1496,20 @@ static void jbd2_mark_journal_empty(journal_t *journal, int write_op) sb->s_sequence = cpu_to_be32(journal->j_tail_sequence); sb->s_start = cpu_to_be32(0); + if (jbd2_has_feature_fast_commit(journal)) { + /* + * When journal is clean, no need to commit fast commit flag and + * make file system incompatible with older kernels. + */ + jbd2_clear_feature_fast_commit(journal); + had_fast_commit = true; + } jbd2_write_superblock(journal, write_op); + if (had_fast_commit) + jbd2_set_feature_fast_commit(journal); + /* Log is no longer empty */ write_lock(&journal->j_state_lock); journal->j_flags |= JBD2_FLUSHED;