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Subject: Re: workqueue thing
From: Peter Zijlstra <peterz@infradead.org>
To: Stijn Devriendt <highguy@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Wed, 23 Dec 2009 09:43:32 +0100
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On Wed, 2009-12-23 at 09:17 +0100, Stijn Devriendt wrote:
> On Tue, Dec 22, 2009 at 7:07 PM, Andi Kleen <andi@firstfloor.org> wrote:
> > One reason I liked a more dynamic frame work for this is that it
> > has the potential to be exposed to user space and allow automatic
> > work partitioning there based on available cores.  User space
> > has a lot more CPU consumption than the kernel.
> >
> Basically, this is exactly what I was trying to solve with my
> sched_wait_block patch. It was broken in all ways, but the ultimate
> goal was to have concurrency managed workqueues (to nick the term)
> in userspace and have a way out when I/O hits the workqueue.

Don't we have the problem of wakeup concurrency here?

Forking on blocking is only half the problem (and imho the easy half).