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Date: Wed, 07 Aug 2013 23:29:30 +0200
From: Andre Oppermann <andre@freebsd.org>
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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: [net] protecting interfaces from races between control and data ?
References: <20130805215319.GA43271@onelab2.iet.unipi.it>
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Cc: Scott Long <scott4long@yahoo.com>, mike@karels.net,
 Bryan Venteicher <bryanv@daemoninthecloset.org>,
 Navdeep Parhar <np@freebsd.org>, net@freebsd.org,
 Giuseppe Lettieri <g.lettieri@iet.unipi.it>, Luigi Rizzo <rizzo@iet.unipi.it>
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On 07.08.2013 22:48, Adrian Chadd wrote:
> On 7 August 2013 13:08, Scott Long <scott4long@yahoo.com> wrote:
>
>> An even rore relevant difference is that taskqueues have a much stronger
>> management API.  Ithreads can only be scheduled by generating a hardware interrupt,
>> can only be drained by calling bus_teardown_intr(), and cannot be paused.  Taskqueues
>> give you direct access to this control.
>
> It would be really nice if we had a software method to trigger an
> ithread to run, like a software interrupt.
>
> It would also be nice to pin taskqueues to CPUs, we can do with
> ithreads at the moment.

Both are implemented on top of kernel threads so it's mostly a matter of
nicely integrating and exposing an API for it.

-- 
Andre