Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 21 May 2005 17:34:37 -0700
From:      Marcel Moolenaar <marcel@xcllnt.net>
To:        Colin Percival <cperciva@freebsd.org>
Cc:        freebsd-arch@freebsd.org
Subject:   Re: Scheduler fixes for hyperthreading
Message-ID:  <aef05e1ae6104223181ad3cf03e11390@xcllnt.net>
In-Reply-To: <428FC00B.3080909@freebsd.org>
References:  <428FC00B.3080909@freebsd.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On May 21, 2005, at 4:11 PM, Colin Percival wrote:

*snip*
>   The following must be done before hyperthreading is re-enabled:
>
> 1. The scheduler must be taught to not run threads on the same
> processor core unless they p_candebug() each other.  For reasons
> of performance and locking, this is probably best accomplished by
> only allowing threads to share a processor core if they belong
> to the same process.
> 2. When a thread is in the kernel, there must be a mechanism for
> it to IPI its siblings and put them to sleep, and then wake them
> up later.  This would be used any time when a thread in the kernel
> is about to handle sensitive data in a non-oblivious manner; IPsec
> is a good example of where this would be necessary.
>
>   Does anyone want to step forward to work on this?

Maybe it's a better idea to describe the problem in much more
detail, rather than dictate what you want someone else to do?
A pointer to where the problem is described/discussed would
do.

Just a thought,

-- 
  Marcel Moolenaar         USPA: A-39004          marcel@xcllnt.net



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?aef05e1ae6104223181ad3cf03e11390>