Re: [PATCH v9 12/12] mm: stop zeroing memory during allocation in vmemmap
From: Pasha Tatashin <hidden>
Date: 2017-10-03 20:28:21
Also in:
linux-arm-kernel, linux-mm, lkml, sparclinux
Hi Michal, I decided not to merge these two patches, because in addition to sparc optimization move, we have this dependancies: mm: zero reserved and unavailable struct pages must be before mm: stop zeroing memory during allocation in vmemmap. Otherwise, we can end-up with struct pages that are not zeroed properly. However, the first patch depends on mm: zero struct pages during initialization As it uses mm_zero_struct_page(). Pasha On 10/03/2017 11:34 AM, Pasha Tatashin wrote:
On 10/03/2017 09:19 AM, Michal Hocko wrote:quoted
On Wed 20-09-17 16:17:14, Pavel Tatashin wrote:quoted
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.comYes, 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