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=-13.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 2A357C433E7 for ; Tue, 1 Sep 2020 03:48:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13BEE205F4 for ; Tue, 1 Sep 2020 03:48:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726117AbgIADsa (ORCPT ); Mon, 31 Aug 2020 23:48:30 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:15047 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725987AbgIADs3 (ORCPT ); Mon, 31 Aug 2020 23:48:29 -0400 X-IronPort-AV: E=Sophos;i="5.76,377,1592841600"; d="scan'208";a="98758136" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 01 Sep 2020 11:48:26 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id A5F2F48990DB; Tue, 1 Sep 2020 11:48:23 +0800 (CST) Received: from [10.167.225.206] (10.167.225.206) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 1 Sep 2020 11:48:22 +0800 Subject: Re: [PATCH] fs: Handle I_DONTCACHE in iput_final() instead of generic_drop_inode() To: Ira Weiny CC: , , , , , References: <20200831101313.168889-1-lihao2018.fnst@cn.fujitsu.com> <20200831171257.GF1422350@iweiny-DESK2.sc.intel.com> From: "Li, Hao" Message-ID: Date: Tue, 1 Sep 2020 11:48:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.1.1 MIME-Version: 1.0 In-Reply-To: <20200831171257.GF1422350@iweiny-DESK2.sc.intel.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Content-Language: en-US X-Originating-IP: [10.167.225.206] X-ClientProxiedBy: G08CNEXCHPEKD06.g08.fujitsu.local (10.167.33.205) To G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) X-yoursite-MailScanner-ID: A5F2F48990DB.ADBB7 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lihao2018.fnst@cn.fujitsu.com Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 2020/9/1 1:12, Ira Weiny wrote: > On Mon, Aug 31, 2020 at 06:13:13PM +0800, Hao Li wrote: >> If generic_drop_inode() returns true, it means iput_final() can evict >> this inode regardless of whether it is dirty or not. If we check >> I_DONTCACHE in generic_drop_inode(), any inode with this bit set will be >> evicted unconditionally. This is not the desired behavior because >> I_DONTCACHE only means the inode shouldn't be cached on the LRU list. >> As for whether we need to evict this inode, this is what >> generic_drop_inode() should do. This patch corrects the usage of >> I_DONTCACHE. >> >> This patch was proposed in [1]. >> >> [1]: https://lore.kernel.org/linux-fsdevel/20200831003407.GE12096@dread.disaster.area/ >> >> Signed-off-by: Hao Li > > Thanks!  I think this looks good, but shouldn't we add?  It seems like this is > a bug right? > > Fixes: dae2f8ed7992 ("fs: Lift XFS_IDONTCACHE to the VFS layer") Yeah, this is more meaningful. I'm not sure if I need to submit a v2 patch, or this tag will be added by the maintainer when applying this patch. I have no experience with this before. Thanks! Regards, Hao Li > > > Reviewed-by: Ira Weiny > >> --- >>  fs/inode.c         | 3 ++- >>  include/linux/fs.h | 3 +-- >>  2 files changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/fs/inode.c b/fs/inode.c >> index 72c4c347afb7..4e45d5ea3d0f 100644 >> --- a/fs/inode.c >> +++ b/fs/inode.c >> @@ -1625,7 +1625,8 @@ static void iput_final(struct inode *inode) >>      else >>          drop = generic_drop_inode(inode); >>   >> -    if (!drop && (sb->s_flags & SB_ACTIVE)) { >> +    if (!drop && !(inode->i_state & I_DONTCACHE) && >> +            (sb->s_flags & SB_ACTIVE)) { >>          inode_add_lru(inode); >>          spin_unlock(&inode->i_lock); >>          return; >> diff --git a/include/linux/fs.h b/include/linux/fs.h >> index e019ea2f1347..93caee80ce47 100644 >> --- a/include/linux/fs.h >> +++ b/include/linux/fs.h >> @@ -2922,8 +2922,7 @@ extern int inode_needs_sync(struct inode *inode); >>  extern int generic_delete_inode(struct inode *inode); >>  static inline int generic_drop_inode(struct inode *inode) >>  { >> -    return !inode->i_nlink || inode_unhashed(inode) || >> -        (inode->i_state & I_DONTCACHE); >> +    return !inode->i_nlink || inode_unhashed(inode); >>  } >>  extern void d_mark_dontcache(struct inode *inode); >>   >> -- >> 2.28.0 >> >> >> > >