Re: boot stall regression due to blk-mq: use percpu_ref for mq usage count

Christoph Hellwig
2014-09-23T05:59:24Z

On Tue, Sep 23, 2014 at 01:56:48AM -0400, Tejun Heo wrote:
> On Tue, Sep 23, 2014 at 07:55:54AM +0200, Christoph Hellwig wrote:
> > Jens,
> >
> > can we simply get these commits reverted from now if there's no better
> > fix? I'd hate to have this boot stall in the first kernel with blk-mq
> > support for scsi.
>
> Patches going out right now.

"[PATCHSET percpu/for-3.18] percpu_ref: implement switch_to_atomic/percpu()"

looks way to big for 3.17, and the regression was introduced in the 3.17
merge window. I'm not sure what was broken before, but it defintively
survived a lot of testing.