From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754628Ab2I0Dyb (ORCPT ); Wed, 26 Sep 2012 23:54:31 -0400 Received: from ipmail07.adl2.internode.on.net ([150.101.137.131]:2030 "EHLO ipmail07.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754529Ab2I0Dy2 (ORCPT ); Wed, 26 Sep 2012 23:54:28 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AqQMACnNY1B5LPfb/2dsb2JhbABFvHgBAoEQgQmCIAEBBAEnExwjBQsIAxUDLhQNGAM0h3MDCQWuDQ2JVBSKImJsSoEzgyADlBSBVIshhQuCeQ Date: Thu, 27 Sep 2012 13:54:25 +1000 From: Dave Chinner To: zwu.kernel@gmail.com 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: <20120927035425.GN15236@dastard> References: <1348404995-14372-1-git-send-email-zwu.kernel@gmail.com> <1348404995-14372-7-git-send-email-zwu.kernel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1348404995-14372-7-git-send-email-zwu.kernel@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. track_hot_inode_ranges(inode, offset, length, rw) { if (inode->i_sb->s_flags & MS_HOT_TRACKING) hot_inode_freq_update(inode, offset, length, rw); } > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index 5ad5ce2..552c861 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -35,6 +35,7 @@ > #include /* __set_page_dirty_buffers */ > #include > #include > +#include > #include > > /* > @@ -1895,13 +1896,33 @@ EXPORT_SYMBOL(generic_writepages); > int do_writepages(struct address_space *mapping, struct writeback_control *wbc) > { > int ret; > + pgoff_t start = 0; > + u64 prev_count = 0, count = 0; > > if (wbc->nr_to_write <= 0) > return 0; > + > + /* Hot data tracking */ > + if (TRACK_THIS_INODE(mapping->host) > + && wbc->range_cyclic) { > + start = mapping->writeback_index << PAGE_CACHE_SHIFT; > + prev_count = (u64)wbc->nr_to_write; > + } Why only wbc->range_cyclic? This won't record things like synchronous writes or fsync-triggered writes, are are far more likely to be to hot ranges in a file... Cheers, Dave. -- Dave Chinner david@fromorbit.com