On Wed, Nov 02, 2011 at 04:02:00PM +0100, Jan Kara wrote:
> That's a good question. Locking of i_flags was always kind of unclear to
> me. They are certainly read without any locks and in the couple of places
> where setting can actually race VFS uses i_mutex for serialization which is
> kind of overkill (and unusable from page fault due to locking constraints).
> Probably using atomic bitops for setting i_flags would be needed.
Adding a set of inode_{test,set,clear}_flag() inline functions, and
then converting accesses of i_flags to use them would be a great
cleanup task. It's been on my mental todo list for a while, but it's
a pretty invasive change. What we have right now is definitely racy,
though, and we only get away with it because i_flags changes happen
relatively rarely. Fixing this would be definitely be a Good Thing.
- Ted
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>