On Fri, Jan 11, 2013 at 09:12:11PM +0100, Jan Kara wrote: > On Thu 10-01-13 13:47:57, Miao Xie wrote: > > writeback_inodes_sb(_nr)_if_idle() is re-implemented by replacing down_read() > > with down_read_trylock() because > > - If ->s_umount is write locked, then the sb is not idle. That is > > writeback_inodes_sb(_nr)_if_idle() needn't wait for the lock. > > - writeback_inodes_sb(_nr)_if_idle() grabs s_umount lock when it want to start > > writeback, it may bring us deadlock problem when doing umount. In order to > > fix the problem, ext4 and btrfs implemented their own writeback functions > > instead of writeback_inodes_sb(_nr)_if_idle(), but it introduced the redundant > > code, it is better to implement a new writeback_inodes_sb(_nr)_if_idle(). > > > > The name of these two functions is cumbersome, so rename them to > > try_to_writeback_inodes_sb(_nr). > > > > This idea came from Christoph Hellwig. > > Some code is from the patch of Kamal Mostafa. > The patch looks good. Thanks! You can add: > Reviewed-by: Jan Kara <jack@xxxxxxx> > > BTW, since changes to filesystems are minimal, maybe Fengguang can take > the patch through his writeback tree? Fengguang? OK, done. The patch looks good, thanks! Fengguang -- 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