The patch titled Subject: mm, page_owner: handle THP splits correctly has been added to the -mm tree. Its filename is mm-page_owner-handle-thp-splits-correctly.patch

This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-page_owner-handle-thp-splits-cor... and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-page_owner-handle-thp-splits-cor...

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------------------------------------------------------ From: Vlastimil Babka vbabka@suse.cz Subject: mm, page_owner: handle THP splits correctly

THP splitting path is missing the split_page_owner() call that split_page() has. As a result, split THP pages are wrongly reported in the page_owner file as order-9 pages. Furthermore when the former head page is freed, the remaining former tail pages are not listed in the page_owner file at all. This patch fixes that by adding the split_page_owner() call into __split_huge_page().

Link: http://lkml.kernel.org/r/20190820131828.22684-2-vbabka@suse.cz Fixes: a9627bc5e34e ("mm/page_owner: introduce split_page_owner and replace manual handling") Reported-by: Kirill A. Shutemov kirill@shutemov.name Signed-off-by: Vlastimil Babka vbabka@suse.cz Cc: Michal Hocko mhocko@kernel.org Cc: Mel Gorman mgorman@techsingularity.net Cc: Matthew Wilcox willy@infradead.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/huge_memory.c | 4 ++++ 1 file changed, 4 insertions(+)

--- a/mm/huge_memory.c~mm-page_owner-handle-thp-splits-correctly +++ a/mm/huge_memory.c @@ -32,6 +32,7 @@ #include <linux/shmem_fs.h> #include <linux/oom.h> #include <linux/numa.h> +#include <linux/page_owner.h>

#include <asm/tlb.h> #include <asm/pgalloc.h> @@ -2516,6 +2517,9 @@ static void __split_huge_page(struct pag }

ClearPageCompound(head); + + split_page_owner(head, HPAGE_PMD_ORDER); + /* See comment in __split_huge_page_tail() */ if (PageAnon(head)) { /* Additional pin to swap cache */ _

Patches currently in -mm which might be from vbabka@suse.cz are

mm-page_owner-handle-thp-splits-correctly.patch mm-page_owner-record-page-owner-for-each-subpage.patch mm-page_owner-keep-owner-info-when-freeing-the-page.patch mm-page_owner-debug_pagealloc-save-and-dump-freeing-stack-trace.patch mm-compaction-clear-total_migratefree_scanned-before-scanning-a-new-zone-fix-2.patch mm-reclaim-cleanup-should_continue_reclaim.patch mm-compaction-raise-compaction-priority-after-it-withdrawns.patch