From patchwork Sat Aug 1 15:46:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 11696127 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BE50E912 for ; Sat, 1 Aug 2020 15:47:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A75E82083E for ; Sat, 1 Aug 2020 15:47:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="pCTnwJf3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726475AbgHAPrJ (ORCPT ); Sat, 1 Aug 2020 11:47:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725841AbgHAPrI (ORCPT ); Sat, 1 Aug 2020 11:47:08 -0400 Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2E03C06174A; Sat, 1 Aug 2020 08:47:08 -0700 (PDT) Received: by mail-pl1-x643.google.com with SMTP id g19so6148737plq.0; Sat, 01 Aug 2020 08:47:08 -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; bh=Mntg9taWes2IQ/63EyCAMBFQrt4r0EuOq++DeO6vhCU=; b=pCTnwJf3v3CtEPpkp/TmvlpTE5l3PmW5NUc45HZbvb18erR72HOH9vChUUZ3YypEyO pOEn+Y6kYFg12fDAXLjxmkkbrloT5baTLdylazRVuGcWyWbHNplhBTFGsHBS3CfSY+2K ZBbY7lcT6b3XDrGT6F4ErIzfUi1DslpZzJhhJT80tMKqGOFgZq3fHliRCoxY3j0MTrwH xaHWwOOL97SXN96TpJXkBVLs1QileWyBIrDM2KDZMp70zWezI8KETWo+zVKFUctCfd7M ZN07e0MHPDGZyxiugOuJhANAGjWuw5kdtYehMPA6KE05ot7lAQKCMW9zrb812vnxcSZF qKiA== 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; bh=Mntg9taWes2IQ/63EyCAMBFQrt4r0EuOq++DeO6vhCU=; b=nPLRmvz1sDtn+gXZQT3vQzghV7/0I7KUNrrpJ5PZvXi/ITc+mXfsKGJw7WHAyI6OTx guYvVr7/TTr24l0wFPrOEw/ilnuez0Nk8m00GCiWSaulSrePkfg5Vy4D/9gQ7Zen1nxa sxjHkzWZ6FyfFWKwEMEcF7PSWGr480knDO5n6pv9Avw+wf3QRiHI6za88TVpFU6vcTPq TVFsBtoHLUwoEBbyG758rKgqrMbB+R9CykEAGFWlZlWADhvCoM5rpUEI9sPCfwVSIHso Pou5J8JMeLQf3iJwZ7Khg5NylRfKr1bFgzLMp6RKcA/XpF1X+CmdLBYg3SBAopPmdh9M lNbg== X-Gm-Message-State: AOAM53386x19cUH5jZ8slaGYbtbQUuLTUuvBLUKeIf51mbrTj3y4vl8i gl4u9cItP74TcgcDz0q6uWY= X-Google-Smtp-Source: ABdhPJzMVdJHi1GV+1Q4tvZMc/xr8ImvgRh9hFVdynekX3JhUv9ic2u08w6+W3V3yISXmtC/v+MQDw== X-Received: by 2002:a17:902:8bc3:: with SMTP id r3mr8070864plo.112.1596296828074; Sat, 01 Aug 2020 08:47:08 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id j26sm13717331pfe.200.2020.08.01.08.47.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 08:47:07 -0700 (PDT) From: Yafang Shao To: david@fromorbit.com, hch@infradead.org, darrick.wong@oracle.com, mhocko@kernel.org, willy@infradead.org Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Yafang Shao Subject: [PATCH v4 1/2] xfs: avoid double restore PF_MEMALLOC_NOFS if transaction reservation fails Date: Sat, 1 Aug 2020 11:46:31 -0400 Message-Id: <20200801154632.866356-2-laoar.shao@gmail.com> X-Mailer: git-send-email 2.18.1 In-Reply-To: <20200801154632.866356-1-laoar.shao@gmail.com> References: <20200801154632.866356-1-laoar.shao@gmail.com> Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: Yafang Shao In xfs_trans_alloc(), if xfs_trans_reserve() fails, it will call xfs_trans_cancel(), in which it will restore the flag PF_MEMALLOC_NOFS. However this flags has been restored in xfs_trans_reserve(). Although this behavior doesn't introduce any obvious issue, we'd better improve it. Signed-off-by: Yafang Shao Cc: Dave Chinner Cc: Christoph Hellwig Cc: Michal Hocko Cc: Darrick J. Wong Cc: Matthew Wilcox Signed-off-by: Matthew Wilcox (Oracle) --- fs/xfs/xfs_trans.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index 3c94e5ff4316..9ff41970d0c7 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -162,10 +162,9 @@ xfs_trans_reserve( */ if (blocks > 0) { error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd); - if (error != 0) { - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + if (error != 0) return -ENOSPC; - } + tp->t_blk_res += blocks; } @@ -240,8 +239,6 @@ xfs_trans_reserve( tp->t_blk_res = 0; } - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); - return error; } @@ -972,6 +969,7 @@ xfs_trans_roll( struct xfs_trans **tpp) { struct xfs_trans *trans = *tpp; + struct xfs_trans *tp; struct xfs_trans_res tres; int error; @@ -1005,5 +1003,10 @@ xfs_trans_roll( * the prior and the next transactions. */ tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; - return xfs_trans_reserve(*tpp, &tres, 0, 0); + tp = *tpp; + error = xfs_trans_reserve(tp, &tres, 0, 0); + if (error) + current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + + return error; }