From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:61275 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754824Ab2I0HMx (ORCPT ); Thu, 27 Sep 2012 03:12:53 -0400 MIME-Version: 1.0 In-Reply-To: <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> <20120927065953.GQ15236@dastard> Date: Thu, 27 Sep 2012 15:12:51 +0800 Message-ID: Subject: Re: [RFC v2 06/10] vfs: enable hot data tracking 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 2:59 PM, Dave Chinner wrote: > 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 Can we not directly define hot_inode_udate_freqs to be a static inline?:) > will just result in no extra overhead other than the if > statement.... > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com -- Regards, Zhi Yong Wu