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Date: Mon, 11 Jan 2010 10:59:37 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Erik Rigtorp <erik@rigtorp.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Monitoring file descriptors without switching context
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> What I really need is some way to have the hardware block and monitor
> IO for me. Would it be feasible to implement a special low latency
> poll() syscall that uses MONITOR/MWAIT instructions to monitor file
> descriptors?

The futex locks are probably the lowest level interface you've got for
interlocking between tasks and are very fast. You can also pin tasks to
groups of cpus so you can create an I/O only core for example.

Alan