From: Vlastimil Babka <vbabka@xxxxxxx> 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@xxxxxxx Fixes: a9627bc5e34e ("mm/page_owner: introduce split_page_owner and replace manual handling") Reported-by: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx> Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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 */ _
