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Date: Fri, 9 Oct 2015 10:27:13 +0100 (IST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andy Lutomirski <luto@amacapital.net>, Christoph Lameter <cl@linux.com>,
        Peter Zijlstra <peterz@infradead.org>
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        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: crazy idea: big percpu lock (Re: task isolation)
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On Thu, 8 Oct 2015, Andy Lutomirski wrote:
> I want to propose a new primitive that might go a long way toward
> solving this issue.  The new primitive would be called the "big percpu
> lock".

It took us 15+ years to get rid of the "Big Kernel Lock", so we really
don't want to add a new "Big XXX Lock". We have enough pain already
with preempt_disable() and local_irq_disable() which are basically
"Big CPU Locks".

Don't ever put BIG and LOCK into one context, really.

Thanks,

	tglx