atime not written to disk

[Timothy Shimmin <tes@sgi.com>]

Hi,

Before I investigate further ;-),
it appears that in XFS (seen in recent xfs-dev tree and on older issp release
on default mkfs/mount options),
that the atime is not being written out to disk in xfs,
at least, in the simple scenario below.

emu:/home/tes # echo bill >/mnt/test/bill
emu:/home/tes # ls -l /mnt/test/bill
-rw-r--r-- 1 root root 5 2008-10-21 16:03 /mnt/test/bill
emu:/home/tes # ls -lu /mnt/test/bill
-rw-r--r-- 1 root root 5 2008-10-21 16:03 /mnt/test/bill

... wait a bit to change the atime...

emu:/home/tes # cat /mnt/test/bill
bill
emu:/home/tes # ls -lu /mnt/test/bill
-rw-r--r-- 1 root root 5 2008-10-21 16:11 /mnt/test/bill

emu:/home/tes # cd /
emu:/ # umount /mnt/test
emu:/ # mount /mnt/test
emu:/mnt/test # ls -lu /mnt/test/bill
-rw-r--r-- 1 root root 5 2008-10-21 16:03 /mnt/test/bill

I believe that the atime is handled by the vfs and in xfs_iflush_int
we sync up with the linux inode.
Perhaps i_update_core needs to be set so that xfs_iflush_int
will proceed and call xfs_synchronize_atime() and
somehow that is not happening??

I haven't looked further yet, but I thought I'd ask on the list
in case others, such as Christoph and Dave have thoughts on this.

Thanks,
Tim.