From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail07.adl2.internode.on.net ([150.101.137.131]:62947 "EHLO ipmail07.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751790Ab2I0G74 (ORCPT ); Thu, 27 Sep 2012 02:59:56 -0400 Date: Thu, 27 Sep 2012 16:59:53 +1000 From: Dave Chinner To: Zhi Yong Wu 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 Subject: Re: [RFC v2 06/10] vfs: enable hot data tracking Message-ID: <20120927065953.GQ15236@dastard> References: <1348404995-14372-1-git-send-email-zwu.kernel@gmail.com> <1348404995-14372-7-git-send-email-zwu.kernel@gmail.com> <20120927035425.GN15236@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, Sep 27, 2012 at 02:28:12PM +0800, Zhi Yong Wu wrote: > On Thu, Sep 27, 2012 at 11:54 AM, Dave Chinner wrote: > > On Sun, Sep 23, 2012 at 08:56:31PM +0800, zwu.kernel@gmail.com wrote: > >> From: Zhi Yong Wu > >> > >> Miscellaneous features that implement hot data tracking > >> and generally make the hot data functions a bit more friendly. > >> > >> Signed-off-by: Zhi Yong Wu > >> --- > >> fs/direct-io.c | 10 ++++++++++ > >> include/linux/hot_tracking.h | 11 +++++++++++ > >> mm/filemap.c | 8 ++++++++ > >> mm/page-writeback.c | 21 +++++++++++++++++++++ > >> mm/readahead.c | 9 +++++++++ > >> 5 files changed, 59 insertions(+), 0 deletions(-) > >> > >> diff --git a/fs/direct-io.c b/fs/direct-io.c > >> index f86c720..3773f44 100644 > >> --- a/fs/direct-io.c > >> +++ b/fs/direct-io.c > >> @@ -37,6 +37,7 @@ > >> #include > >> #include > >> #include > >> +#include "hot_tracking.h" > >> > >> /* > >> * How many user pages to map in one call to get_user_pages(). This determines > >> @@ -1297,6 +1298,15 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, > >> prefetch(bdev->bd_queue); > >> prefetch((char *)bdev->bd_queue + SMP_CACHE_BYTES); > >> > >> + /* Hot data tracking */ > >> + if (TRACK_THIS_INODE(iocb->ki_filp->f_mapping->host) > >> + && iov_length(iov, nr_segs) > 0) { > >> + hot_rb_update_freqs(iocb->ki_filp->f_mapping->host, > >> + (u64)offset, > >> + (u64)iov_length(iov, nr_segs), > >> + rw & WRITE); > >> + } > > > > That's a bit messy. I'd prefer a static inline function that hides > > all this. e.g. > Do you think of moving the condition into hot_inode_udate_freqs(), not > adding another new function? Moving it into hot_inode_udate_freqs() will add a function call overhead even when tracking is not enabled. a static inline function will just result in no extra overhead other than the if statement.... Cheers, Dave. -- Dave Chinner david@fromorbit.com