Re: [PATCH 2/9] ext4: honor the O_SYNC flag for aysnchronous direct I/O requests

Jan Kara
2012-11-21T16:54:43Z

On Wed 21-11-12 09:09:41, Jeff Moyer wrote:
> Jan Kara <jack@suse.cz> writes:
>
> >> Just to be clear, are you saying you would like me to remove the
> >> mutex_lock/unlock pair from ext4_sync_file? (I had already factored out
> >> the common code between this new code path and the fsync path in my tree.)
> > Yes, after some thinking I came to that conclusion. We actually need to
> > keep i_mutex around ext4_flush_unwritten_io() to avoid livelocks but the
> > rest doesn't need it. The change should be definitely a separate patch just
> > in case there's something subtle I missed and we need to bisect in
> > future... I've attached a patch for that so that blame for bugs goes my way
> > ;) Compile tested only so far. I'll give it some more testing overnight.
>
> Great, thanks Jan! I'll include this in the next posting.
OK, patch passed xfstests and a test banging one file with random IO and
fsyncs from 8 processes (in data=ordered, data=journal, and nojournal
modes). So it seems I didn't miss anything substantial. So ship it! ;)

Honza
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR