Subject: Re: [patch 1/2] mm: remove GFP_THISNODE

From: Vlastimil Babka <[email-masked]>
Date: Fri, 27 Feb 2015 23:52:56 +0100

On 27.2.2015 23:31, David Rientjes wrote:
> On Fri, 27 Feb 2015, Vlastimil Babka wrote:
>
>>> Do you see any issues with either patch 1/2 or patch 2/2 besides the
>>> s/GFP_TRANSHUGE/GFP_THISNODE/ that is necessary on the changelog?
>> Well, my point is, what if the node we are explicitly trying to allocate
>> hugepage on, is in fact not allowed by our cpuset? This could happen in the page
>> fault case, no? Although in a weird configuration when process can (and really
>> gets scheduled to run) on a node where it is not allowed to allocate from...
>>
> If the process is running a node that is not allowed by the cpuset, then
> alloc_hugepage_vma() now fails with VM_FAULT_FALLBACK.  That was the
> intended policy change of commit 077fcf116c8c ("mm/thp: allocate
> transparent hugepages on local node").

Ah, right, didn't realize that mempolicy also takes that into account.
Thanks for removing the exception anyway.

>
>   [ alloc_hugepage_vma() should probably be using numa_mem_id() instead for
>     memoryless node platforms. ]

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to [email-masked].  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email-masked]"> [email-masked] </a>