From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: [PATCH] mm: Add new vma flag VM_LOCAL_CPU
To: Peter Zijlstra <peterz@infradead.org>, Boaz Harrosh <boazh@netapp.com>
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CC: Matthew Wilcox <willy@infradead.org>, Andrew Morton
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From: Boaz Harrosh <boazh@netapp.com>
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Date: Tue, 15 May 2018 17:36:44 +0300
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On 15/05/18 17:17, Peter Zijlstra wrote:
<>
>>
>> So I would love some mm guy to explain where are those bits collected?
> 
> Depends on the architecture, some architectures only ever set bits,
> some, like x86, clear bits again. You want to look at switch_mm().
> 
> Basically x86 clears the bit again when we switch away from the mm and
> have/will invalidate TLBs for it in doing so.
> 

Ha, OK I am starting to get a picture.

>> Which brings me to another question. How can I find from
>> within a thread Say at the file_operations->mmap() call that the thread
>> is indeed core-pinned. What mm_cpumask should I inspect?
> 
> is_percpu_thread().

Right thank you a lot Peter. this helps.

Boaz
> .
>