On 5/14/14, 5:37 PM, Dave Chinner wrote: > On Thu, May 15, 2014 at 08:00:52AM +1000, Dave Chinner wrote: >> On Wed, May 14, 2014 at 01:39:45PM +0200, Jan Kara wrote: >>> On Wed 14-05-14 13:26:21, Mateusz Guzik wrote: >>>> On Wed, May 14, 2014 at 01:14:49PM +0200, Jan Kara wrote: >>>>> On Wed 14-05-14 00:04:43, Mateusz Guzik wrote: >>>>>> This helps hang troubleshooting efforts when only dmesg is available. >>>>>> >>>>>> While here remove code duplication with MS_RDONLY case and fix a >>>>>> whitespace nit. >>>>> I'm somewhat undecided here I have to say. On one hand I don't like >>>>> printing to kernel log when everything is fine and kernel is operating >>>>> normally. On the other hand I've seen quite a few cases where people have >>>>> shot themselves in the foot with filesystem freezing so having some trace >>>>> of this in the log doesn't seem like a completely bad thing either. What do >>>>> other people think? >>>>> >>>> >>>> I would like to note that the kernel already prints messages when e.g. >>>> filesystems get mounted. >>> Yeah, that's a fair point. >> >> But filesystems choose to output that info, not the VFS. When you do >> a remount,ro there is no output in syslog, because filesystems don't >> need to dump any output - the state change is reflected in >> /proc/self/mounts. IMO frozen should state should be communicated >> the same way so that it is silent when it just works, and the state >> can easily be determined when something goes wrong. > > Say, like this: > > $ grep /mnt/test /proc/mounts > /dev/vda /mnt/test xfs rw,relatime,attr2,inode64,noquota 0 0 > $ sudo xfs_freeze -f /mnt/test > $ grep /mnt/test /proc/mounts > /dev/vda /mnt/test xfs rw,frozen,relatime,attr2,inode64,noquota 0 0 > $ sudo xfs_freeze -u /mnt/test > $ grep /mnt/test /proc/mounts > /dev/vda /mnt/test xfs rw,relatime,attr2,inode64,noquota 0 0 > $ I'm not totally convinced that including a non-mount option in what has always (?) been a list of mount options is a great idea. (Granted, some options there are defaults, and weren't actually specified as a mount option, but if they had been, they'd have been accepted). Maybe add a "mount -o remount,frozen" handler ? ;) -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
