On Thu, Sep 27, 2012 at 2:59 PM, Dave Chinner [off-list ref] wrote:

On Thu, Sep 27, 2012 at 02:28:12PM +0800, Zhi Yong Wu wrote:

quoted

On Thu, Sep 27, 2012 at 11:54 AM, Dave Chinner [off-list ref] wrote:

quoted

On Sun, Sep 23, 2012 at 08:56:31PM +0800, zwu.kernel@gmail.com wrote:

quoted

From: Zhi Yong Wu <redacted>

  Miscellaneous features that implement hot data tracking
and generally make the hot data functions a bit more friendly.

Signed-off-by: Zhi Yong Wu <redacted>
---
 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 <linux/uio.h>
 #include <linux/atomic.h>
 #include <linux/prefetch.h>
+#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