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Subject: Re: [patch v2 -mm] mm, hugetlb: schedule when potentially allocating
 many hugepages
To: David Rientjes <rientjes@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Kravetz <mike.kravetz@oracle.com>
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Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
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From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Date: Thu, 6 Jul 2017 11:38:02 +0530
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On 06/10/2017 04:06 AM, David Rientjes wrote:
> A few hugetlb allocators loop while calling the page allocator and can
> potentially prevent rescheduling if the page allocator slowpath is not
> utilized.
> 
> Conditionally schedule when large numbers of hugepages can be allocated.
> 
> Signed-off-by: David Rientjes <rientjes@google.com>

Fixes a task which was getting hung while writing like 10000
hugepages (16MB on POWER8) into /proc/sys/vm/nr_hugepages.

Tested-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>