From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:42195 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754321Ab2I0Can (ORCPT ); Wed, 26 Sep 2012 22:30:43 -0400 MIME-Version: 1.0 In-Reply-To: <20120927022045.GK15236@dastard> References: <1348404995-14372-1-git-send-email-zwu.kernel@gmail.com> <1348404995-14372-4-git-send-email-zwu.kernel@gmail.com> <20120925092819.GC29154@dastard> <20120927022045.GK15236@dastard> Date: Thu, 27 Sep 2012 10:30:41 +0800 Message-ID: Subject: Re: [RFC v2 03/10] vfs: add one new mount option '-o hottrack' From: Zhi Yong Wu To: Dave Chinner Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linuxram@linux.vnet.ibm.com, viro@zeniv.linux.org.uk, cmm@us.ibm.com, tytso@mit.edu, marco.stornelli@gmail.com, stroetmann@ontolinux.com, diegocg@gmail.com, chris@csamuel.org, Zhi Yong Wu Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, Sep 27, 2012 at 10:20 AM, Dave Chinner wrote: > On Wed, Sep 26, 2012 at 10:56:08AM +0800, Zhi Yong Wu wrote: >> On Tue, Sep 25, 2012 at 5:28 PM, Dave Chinner wrote: >> > On Sun, Sep 23, 2012 at 08:56:28PM +0800, zwu.kernel@gmail.com wrote: >> >> From: Zhi Yong Wu >> >> >> >> Introduce one new mount option '-o hottrack', >> >> and add its parsing support. >> >> Its usage looks like: >> >> mount -o hottrack >> >> mount -o nouser,hottrack >> >> mount -o nouser,hottrack,loop >> >> mount -o hottrack,nouser >> > >> > I think that this option parsing should be done by the filesystem, >> > even though the tracking functionality is in the VFS. That way ony >> > the filesystems that can use the tracking information will turn it >> > on, rather than being able to turn it on for everything regardless >> > of whether it is useful or not. >> > >> > Along those lines, just using a normal superblock flag to indicate >> > it is active (e.g. MS_HOT_INODE_TRACKING in sb->s_flags) means you >> > don't need to allocate the sb->s_hot_info structure just to be able >> > to check whether we are tracking hot inodes or not. >> > >> > This then means the hot inode tracking for the superblock can be >> > initialised by the filesystem as part of it's fill_super method, >> > along with the filesystem specific code that will use the hot >> > tracking information the VFS gathers.... >> I can see what you mean, but don't know if other guys also agree with this. >> If so, all FS specific code which use hot tracking feature wll have to add >> the same chunk of code in it fill_super method. Is it good? > > Most filesystems will only need to add 3-4 lines of code to their > existing parser, so it's not a big deal I think... OK, i try to do it. thanks a lot. > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com -- Regards, Zhi Yong Wu