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Subject: Re: [PATCH v9 12/12] mm: stop zeroing memory during allocation in
 vmemmap
To: Michal Hocko <mhocko@kernel.org>
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From: Pasha Tatashin <pasha.tatashin@oracle.com>
Message-ID: <c028f65a-b4a6-e56d-3a50-5d7ad9af50cb@oracle.com>
Date: Tue, 3 Oct 2017 11:34:25 -0400
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On 10/03/2017 09:19 AM, Michal Hocko wrote:
> On Wed 20-09-17 16:17:14, Pavel Tatashin wrote:
>> vmemmap_alloc_block() will no longer zero the block, so zero memory
>> at its call sites for everything except struct pages.  Struct page memory
>> is zero'd by struct page initialization.
>>
>> Replace allocators in sprase-vmemmap to use the non-zeroing version. So,
>> we will get the performance improvement by zeroing the memory in parallel
>> when struct pages are zeroed.
> 
> Is it possible to merge this patch with http://lkml.kernel.org/r/20170920201714.19817-7-pasha.tatashin@oracle.com

Yes, I will do that. It would also require re-arranging
[PATCH v9 07/12] sparc64: optimized struct page zeroing
optimization to come after this patch.

Pasha