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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B00DEC3065A for ; Mon, 1 Jul 2024 15:24:49 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0D3CE6B0088; Mon, 1 Jul 2024 11:24:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 06D646B008A; Mon, 1 Jul 2024 11:24:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E186A6B0092; Mon, 1 Jul 2024 11:24:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id C37436B0088 for ; Mon, 1 Jul 2024 11:24:48 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 60C9A121E15 for ; Mon, 1 Jul 2024 15:24:48 +0000 (UTC) X-FDA: 82291556256.27.B7DE4E0 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.223.130]) by imf07.hostedemail.com (Postfix) with ESMTP id 023E740010 for ; Mon, 1 Jul 2024 15:24:44 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=eYVMLLHU; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=3P9wJM2V; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=eYVMLLHU; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=3P9wJM2V; dmarc=none; spf=pass (imf07.hostedemail.com: domain of dsterba@suse.cz designates 195.135.223.130 as permitted sender) smtp.mailfrom=dsterba@suse.cz ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719847467; a=rsa-sha256; cv=none; b=5GAN+Lr4Uh1CJfvV/e8BI8MxxK6cHXMLczzGBW7Ff2koHXpOHG/8+2If1bHMU5/JOcGAik 2VWFWptJA6oZdpPbmw/Ly2JOu47TCppWiCoqzXf7s2g5XboXSFzb7i5Okpx+BXdguLsciF jPcMGcPm3jVBysoiYwmqPtWth0tS+s8= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=eYVMLLHU; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=3P9wJM2V; dkim=pass header.d=suse.cz header.s=susede2_rsa header.b=eYVMLLHU; dkim=pass header.d=suse.cz header.s=susede2_ed25519 header.b=3P9wJM2V; dmarc=none; spf=pass (imf07.hostedemail.com: domain of dsterba@suse.cz designates 195.135.223.130 as permitted sender) smtp.mailfrom=dsterba@suse.cz ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719847467; h=from:from:sender:reply-to: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Cj7Ce9Ym/sfb2sDvLTmuCL9ctsqC7G9CNBaQC/7mpWM=; b=LU4zUqAcn1SsVf92OX4dAjUQ2oPFwnK4PWffcHLs3MvoIG4fLEL+MtGUuiPZyONbOQ3e6j WdTRCWffdM1Q9sLjzfNKFE4E5fj5n5uQza1sbsIiEoT99+lp4W/hMFRqmihXKzTvsFvexM pSpGo1upAw0A4YCu0JYJ/HXUkNj51nE= Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id B3EC6219B9; Mon, 1 Jul 2024 15:24:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1719847482; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Cj7Ce9Ym/sfb2sDvLTmuCL9ctsqC7G9CNBaQC/7mpWM=; b=eYVMLLHUiywmTNc4rCPjIViO/DXO6iAHpwDw3qE1A+yHT4hB7jZHK1vNq4S3Qya2hj8Nzx nnM1jC+Thkp777m+eNkDMsAptyMFvtINhgXBUlkLuEiIXUCDqLLCtepT1ZBwH4WW+6Hltb BzJbls++BS91/poXGjWflmBHtxstYC8= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1719847482; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Cj7Ce9Ym/sfb2sDvLTmuCL9ctsqC7G9CNBaQC/7mpWM=; b=3P9wJM2V7xu/1owrLE9QMz9guXL/Sm7CRWt/qRwbHWrdRhAzDyrohNPLfez4VmKwn2ohzV q4G6XkTbAnBbldCA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1719847482; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Cj7Ce9Ym/sfb2sDvLTmuCL9ctsqC7G9CNBaQC/7mpWM=; b=eYVMLLHUiywmTNc4rCPjIViO/DXO6iAHpwDw3qE1A+yHT4hB7jZHK1vNq4S3Qya2hj8Nzx nnM1jC+Thkp777m+eNkDMsAptyMFvtINhgXBUlkLuEiIXUCDqLLCtepT1ZBwH4WW+6Hltb BzJbls++BS91/poXGjWflmBHtxstYC8= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1719847482; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Cj7Ce9Ym/sfb2sDvLTmuCL9ctsqC7G9CNBaQC/7mpWM=; b=3P9wJM2V7xu/1owrLE9QMz9guXL/Sm7CRWt/qRwbHWrdRhAzDyrohNPLfez4VmKwn2ohzV q4G6XkTbAnBbldCA== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 6A55613800; Mon, 1 Jul 2024 15:24:42 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 9mq8GTrKgmZuAgAAD6G6ig (envelope-from ); Mon, 01 Jul 2024 15:24:42 +0000 Date: Mon, 1 Jul 2024 17:24:37 +0200 From: David Sterba To: Jeff Layton Cc: Josef Bacik , Alexander Viro , Christian Brauner , Jan Kara , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Chandan Babu R , "Darrick J. Wong" , Theodore Ts'o , Andreas Dilger , Chris Mason , David Sterba , Hugh Dickins , Andrew Morton , Andi Kleen , kernel-team@fb.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org Subject: Re: [PATCH v2 09/11] btrfs: convert to multigrain timestamps Message-ID: <20240701152437.GE21023@twin.jikos.cz> Reply-To: dsterba@suse.cz References: <20240701-mgtime-v2-0-19d412a940d9@kernel.org> <20240701-mgtime-v2-9-19d412a940d9@kernel.org> <20240701134936.GB504479@perftesting> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 023E740010 X-Stat-Signature: nstipp5o55t7nkn96u93o63ju7mwfcbz X-Rspam-User: X-HE-Tag: 1719847484-559388 X-HE-Meta: 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 C4tlOFjt qWl/KxZKDcrUoT4hXZocqMC/F/4wKXuLfagKXoQOCdSXZitLCe/xAyEVDxO0sFoMPCzeZ8nlPfeT2GTRAP/6NFiDc5TmolnRpEKZXH1vkLh2wlfUUk4rDwoUZ7NPiXyDwVyx+E7GyIJ4F1WUG4UY0wLckfmOrIU/XwpJoDJw8CRUY20EvMQlhoYFOQhQAb+5vN5kuw+2xyZqMnkFHngVwzvsepvdPbEb9HG/xDP8KRe/pzfEtIX1RpeHJuLWzuBAMABigpZ2vWB+p8YTrLVjDOJHDbToSMhpGlScK8nvm4P/58LMudAV23LAAHZeS4UNLlJSk9QqKoRaQayfh3UMAealSVYgITEygTSE247dQujloFoo= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Jul 01, 2024 at 09:57:43AM -0400, Jeff Layton wrote: > On Mon, 2024-07-01 at 09:49 -0400, Josef Bacik wrote: > > On Mon, Jul 01, 2024 at 06:26:45AM -0400, Jeff Layton wrote: > > > Enable multigrain timestamps, which should ensure that there is an > > > apparent change to the timestamp whenever it has been written after > > > being actively observed via getattr. > > > > > > Beyond enabling the FS_MGTIME flag, this patch eliminates > > > update_time_for_write, which goes to great pains to avoid in-memory > > > stores. Just have it overwrite the timestamps unconditionally. > > > > > > Signed-off-by: Jeff Layton > > > --- > > >  fs/btrfs/file.c  | 25 ++++--------------------- > > >  fs/btrfs/super.c |  3 ++- > > >  2 files changed, 6 insertions(+), 22 deletions(-) > > > > > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > > > index d90138683a0a..409628c0c3cc 100644 > > > --- a/fs/btrfs/file.c > > > +++ b/fs/btrfs/file.c > > > @@ -1120,26 +1120,6 @@ void btrfs_check_nocow_unlock(struct > > > btrfs_inode *inode) > > >   btrfs_drew_write_unlock(&inode->root->snapshot_lock); > > >  } > > >   > > > -static void update_time_for_write(struct inode *inode) > > > -{ > > > - struct timespec64 now, ts; > > > - > > > - if (IS_NOCMTIME(inode)) > > > - return; > > > - > > > - now = current_time(inode); > > > - ts = inode_get_mtime(inode); > > > - if (!timespec64_equal(&ts, &now)) > > > - inode_set_mtime_to_ts(inode, now); > > > - > > > - ts = inode_get_ctime(inode); > > > - if (!timespec64_equal(&ts, &now)) > > > - inode_set_ctime_to_ts(inode, now); > > > - > > > - if (IS_I_VERSION(inode)) > > > - inode_inc_iversion(inode); > > > -} > > > - > > >  static int btrfs_write_check(struct kiocb *iocb, struct iov_iter > > > *from, > > >        size_t count) > > >  { > > > @@ -1171,7 +1151,10 @@ static int btrfs_write_check(struct kiocb > > > *iocb, struct iov_iter *from, > > >   * need to start yet another transaction to update the > > > inode as we will > > >   * update the inode when we finish writing whatever data > > > we write. > > >   */ > > > - update_time_for_write(inode); > > > + if (!IS_NOCMTIME(inode)) { > > > + inode_set_mtime_to_ts(inode, > > > inode_set_ctime_current(inode)); > > > + inode_inc_iversion(inode); > > > > You've dropped the > > > > if (IS_I_VERSION(inode)) > > > > check here, and it doesn't appear to be in inode_inc_iversion.  Is > > there a > > reason for this?  Thanks, > > > > AFAICT, btrfs always sets SB_I_VERSION. Are there any cases where it > isn't? If so, then I can put this check back. I'll make a note about it > in the changelog if not. Yes it's always set and I don't see anything in the generic code that would unset it so it's safe to drop the IS_I_VERSION check. The check was originally added in November 2012 by 6c760c072403f4 ("Btrfs: do not call file_update_time in aio_write") and then moved a few times. Enabling the super block flags was added in May 2012 by 0c4d2d95d06e92 ("Btrfs: use i_version instead of our own sequence") so the check was not necessary from the beginning.