From: Miaohe Lin linmiaohe@huawei.com
[ Upstream commit a17206dac7b262e7abed5a05e34a6bd6bd0a9b06 ]
There is nothing to do if a zone doesn't have any pages managed by the buddy allocator. So we should check managed_zone instead. Also if a thp is found, there's no need to traverse the subpages again.
Link: https://lkml.kernel.org/r/20220704132201.14611-13-linmiaohe@huawei.com Signed-off-by: Miaohe Lin linmiaohe@huawei.com Cc: Matthew Wilcox willy@infradead.org Cc: Muchun Song songmuchun@bytedance.com Cc: Yang Shi shy828301@gmail.com Cc: Zach O'Keefe zokeefe@google.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Stable-dep-of: 2b7aa91ba0e8 ("mm/huge_memory: use pfn_to_online_page() in split_huge_pages_all()") Signed-off-by: Sasha Levin sashal@kernel.org --- mm/huge_memory.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8cc150a88361..34d2979489fd 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2879,9 +2879,12 @@ static void split_huge_pages_all(void) unsigned long total = 0, split = 0;
pr_debug("Split all THPs\n"); - for_each_populated_zone(zone) { + for_each_zone(zone) { + if (!managed_zone(zone)) + continue; max_zone_pfn = zone_end_pfn(zone); for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) { + int nr_pages; if (!pfn_valid(pfn)) continue;
@@ -2897,8 +2900,10 @@ static void split_huge_pages_all(void)
total++; lock_page(page); + nr_pages = thp_nr_pages(page); if (!split_huge_page(page)) split++; + pfn += nr_pages - 1; unlock_page(page); next: put_page(page);