Re: [RFC 09/13] x86/mm: Disable interrupts when flushing the TLB using CR3

From: Dave Hansen
Date: Wed Jan 13 2016 - 18:44:25 EST


On 01/13/2016 03:35 PM, Andy Lutomirski wrote:
> Can anyone here ask a hardware or microcode person what's going on
> with CR3 writes possibly being faster than INVPCID? Is there some
> trick to it?

I just went and measured it myself this morning. "INVPCID Type 3" (all
contexts no global) on a Skylake system was 15% slower than a CR3 write.

Is that in the same ballpark from what you've observed?