On Mon, 16 Apr 2018 16:57:12 +0530 "Aneesh Kumar K.V" <aneesh.ku...@linux.ibm.com> wrote:
> This patch series add split pmd pagetable lock for book3s64. nohash64 also > should > be able to switch to this. I need to workout the code dependency. This series > also migh have broken the build on platforms otherthan book3s64. I am sending > this early > to get feedback on whether we should continue with the approach. > > We switch the pmd allocator to use something similar to what we already use > for > level 4 pagetable allocation. We get an order 0 page and divide that to > fragments > and hand over fragments when we get request for a pmd pagetable. The pmd lock > is > now stashed in the struct page backing the allocated page. That's only for the THP case right? > > The series helps in reducing lock contention on mm->page_table_lock. > The numbers look good.
