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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 38672C433F5 for ; Tue, 17 May 2022 11:28:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239160AbiEQL20 (ORCPT ); Tue, 17 May 2022 07:28:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34678 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229760AbiEQL2Y (ORCPT ); Tue, 17 May 2022 07:28:24 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1A4F37A1C; Tue, 17 May 2022 04:28:23 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 67C321F383; Tue, 17 May 2022 11:28:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1652786902; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3wqdcvLYWrYzghVSBNiA5efGrOvm2RRy916DXEi5jaA=; b=jCwF+yZnKGecO7iFeHrW5jnZf1awNRcaGA7uajnkuCgRjuy1kBMd+YFLwiv0HDIjX1yhga fMa+JBFvSL2+l2VHykDVabTFLpVrqhbBHQEdLDevGQPHBBx+GFzSrKd++OuEd03yZBobtT XPJy/8ThNHtu0I1CI6A4k2NwyV+ZlCw= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1652786902; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3wqdcvLYWrYzghVSBNiA5efGrOvm2RRy916DXEi5jaA=; b=lUqiH+SkWL+XNb6mdFmo3rRUAfka+mCV86TFi8DeiFlKYwkiGHmf5RG89e1k62qiM/mg/1 642epCCyoE+Au3BQ== Received: from quack3.suse.cz (unknown [10.163.43.118]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 562B52C141; Tue, 17 May 2022 11:28:22 +0000 (UTC) Received: by quack3.suse.cz (Postfix, from userid 1000) id 8E957A0631; Tue, 17 May 2022 13:28:16 +0200 (CEST) Date: Tue, 17 May 2022 13:28:16 +0200 From: Jan Kara To: Stefan Roesch Cc: io-uring@vger.kernel.org, kernel-team@fb.com, linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, david@fromorbit.com, jack@suse.cz Subject: Re: [RFC PATCH v2 08/16] fs: add pending file update time flag. Message-ID: <20220517112816.ygkadxcjcfcirauo@quack3.lan> References: <20220516164718.2419891-1-shr@fb.com> <20220516164718.2419891-9-shr@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220516164718.2419891-9-shr@fb.com> Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Mon 16-05-22 09:47:10, Stefan Roesch wrote: > This introduces an optimization for the update time flag and async > buffered writes. While an update of the file modification time is > pending and is handled by the workers, concurrent writes do not need > to wait for this time update to complete. > > Signed-off-by: Stefan Roesch > --- > fs/inode.c | 1 + > include/linux/fs.h | 3 +++ > 2 files changed, 4 insertions(+) > > diff --git a/fs/inode.c b/fs/inode.c > index 1d0b02763e98..fd18b2c1b7c4 100644 > --- a/fs/inode.c > +++ b/fs/inode.c > @@ -2091,6 +2091,7 @@ static int do_file_update_time(struct inode *inode, struct file *file, > return 0; > > ret = inode_update_time(inode, now, sync_mode); > + inode->i_flags &= ~S_PENDING_TIME; So what protects this update of inode->i_flags? Usually we use inode->i_rwsem for that but not all file_update_time() callers hold it... Honza -- Jan Kara SUSE Labs, CR