Re: [2.6.6-mm4-ff1] I/O context isolation

[Jens Axboe <axboe@suse.de>]

On Fri, May 21 2004, Nick Piggin wrote:
> FabF wrote:
> >Jens,
> >
> >	Here's ff1 patchset to have generic I/O context.
> >ff1 : Export io context operations from blkdev/ll_rw_blk (ok)
> >ff2 : Make io_context generic plateform by importing IO stuff from
> >as_io.
> >
> 
> Can I just ask why you want as_io_context in generic code?
> It is currently nicely hidden away in as-iosched.c where
> nobody else needs to ever see it.

I think (it's the only reason I can think of) that he is trying to make
the anticipation generic. Am I correct?

> >	AFAICS, cfq_queue for instance could disappear when using io_context
> >but I think elv_data should remain elevator side....
> >I don't want to go in the wild here so if you've got suggestions, don't
> >hesitate ;)
> >
> 
> cfq_queue is per-queue-per-process. io_context is just
> per-process, so it isn't a trivial replacement.

Definitely not, I struggled quite a bit with such a transformation in
cfq + ioprio.

-- 
Jens Axboe