From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Hall <mhall@mhcomputing.net>
Subject: Re: More KNI performance
Date: Fri, 5 Jun 2015 10:00:59 -0700
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To: Jay Rolette <rolette@infiniteio.com>
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On Fri, Jun 05, 2015 at 10:27:21AM -0500, Jay Rolette wrote:
> Is there some mechanism available that the KNI kernel thread could sleep
> periodically, but somehow be awoken from user space?

This is wildly unvalidated, but futex and SysV semaphore appear to be 
accessible from the kernel side. SysV semaphore sounds a bit cleaner for what 
you're attempting.

http://stackoverflow.com/questions/17391276/shared-semaphore-between-user-and-kernel-spaces

> So far it looks like adding a syscall is about the only path to let a
> user-space app kick a kernel thread. I haven't gotten as far as figuring
> out the details to make sure this all works in practice.

Matthew.