Re: [PATCH 02/27] xfs: re-enable non-blocking behaviour in xfs_map_blocks

Christoph Hellwig
2011-07-06T06:37:02Z

On Tue, Jul 05, 2011 at 05:35:19PM -0500, Alex Elder wrote:
> On Fri, 2011-07-01 at 05:43 -0400, Christoph Hellwig wrote:
> > The non-blockig behaviour in xfs_map_blocks currently is conditional on
> > having both the WB_SYNC_NONE sync_mode and the nonblocking flag set.
> > The latter used to be used by both pdflush, kswapd and a few other places
> > in older kernels, but has been fading out starting with the introduction
> > of the per-bdi flusher threads.
> >
> > Enable the non-blocking behaviour for all WB_SYNC_NONE calls to get back
> > the behaviour we want.
>
> The subject line should refer to xfs_vm_writepage()
> (not xfs_map_blocks()). Unless I hear otherwise I
> will plan to change that for you.

Well, the actual xfs_ilock_nowait call is in xfs_map_blocks, the logic
controlling it in xfs_vm_writepage, so either one is fine.