Re: INVLPG Instruction

From: Arjan van de Ven
Date: Sat Nov 12 2011 - 21:40:07 EST


On Sat, 12 Nov 2011 19:59:44 -0500
Xin Tong <xerox.time.tech@xxxxxxxxx> wrote:

> Hello
>
> When a process has a page fault and Linux swaps out a page ( no more
> free page ) from another process and give it to the page-faulting
> process. Typically a INVLPG is used to invalidate entries in the TLB.
> I would like to know whether INVLPG is global ( i.e. across all cores
> )? How does the process which Linux stole the page from get informed (
> how is its tlb invalidated) ?

invlpg is not "global" in the way you mean it (nor in the sense of
"global pte's").
The kernel will do an IPI to the processors that have a possibility to
have this page in the TLB and do a local flush there.



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Arjan van de Ven Intel Open Source Technology Centre
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