Re: [RFC PATCH 2/8] jump label v4 - x86: Introduce generic jumppatching without stop_machine

From: Mathieu Desnoyers
Date: Mon Jan 18 2010 - 11:54:51 EST

* Arjan van de Ven (arjan@xxxxxxxxxxxxx) wrote:
> On Mon, 18 Jan 2010 10:59:30 -0500
> Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
> > Yeah, so in the latest patch, I updated it to use int3 even if
> > len == 1. :-)
> >
> int3 is not making a difference for your case; there is no guarantee
> that the other processor even sees the "int3 inbetween state" at all;
> if it's not safe without int3 then it won't be safe with int3 either.

What Masami means is that he updated his patch to use the int3+IPI
broadcast scheme.

Therefore, the CPUs not seeing the int3 inbetween state will be forced
to issue a serializing instruction while the int3 is in place anyway.



> --
> Arjan van de Ven Intel Open Source Technology Centre
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Mathieu Desnoyers
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