INVLPG Instruction

INVLPG Instruction

[Xin Tong]

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) ?

Thanks

Re: INVLPG Instruction

[Arjan van de Ven]

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



-- 
Arjan van de Ven 	Intel Open Source Technology Centre
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