Re: [RFC] [PATCH] A clean approach to writeout throttling

Andrew Morton
2007-12-07T00:29:52Z

On Thu, 6 Dec 2007 16:04:41 -0800
Daniel Phillips <phillips@phunq.net> wrote:

> The runner up key idea is that we will gain a notion of "block device
> stack" (or block stack for short, so that we may implement block
> stackers) which for the time being will simply be Device Mapper's
> notion of device stack, however many warts that may have. It's there
> now and we use it for ddsnap.

Perhaps all we need to track is the outermost point?

submit_bio(...)
{
bool remove_the_rq = false;

...
if (current->the_rq == NULL) {
current->the_rq = rq;
remove_the_rq = true;
}
...
if (remove_the_rq)
current->the_rq = NULL;
}

?