From: Baolin Wang baolin.wang@linux.alibaba.com
mainline inclusion from mainline-v6.9-rc2 commit 835c3a25aa373d486514e4e0f5a7450ea82ae489 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9S4Z4 CVE: NA
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Now the mTHP can also be split or added into the deferred list, so add folio_test_pmd_mappable() validation for PMD mapped THP, to avoid confusion with PMD mapped THP related statistics.
[baolin.wang@linux.alibaba.com: check THP earlier in case folio is split, per Lance] Link: https://lkml.kernel.org/r/b99f8cb14bc85fdb6ab43721d1331cb5ebed2581.171377104... Link: https://lkml.kernel.org/r/a5341defeef27c9ac7b85c97f030f93e4368bbc1.171169485... Signed-off-by: Baolin Wang baolin.wang@linux.alibaba.com Acked-by: David Hildenbrand david@redhat.com Reviewed-by: Lance Yang ioworker0@gmail.com Cc: Muchun Song muchun.song@linux.dev Signed-off-by: Andrew Morton akpm@linux-foundation.org (cherry picked from commit 835c3a25aa373d486514e4e0f5a7450ea82ae489) Signed-off-by: Kefeng Wang wangkefeng.wang@huawei.com --- mm/huge_memory.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fe812b3e38f7..a18138e8ebe2 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3155,6 +3155,7 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, XA_STATE_ORDER(xas, &folio->mapping->i_pages, folio->index, new_order); struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; + bool is_thp = folio_test_pmd_mappable(folio); int extra_pins, ret; pgoff_t end; bool is_hzp; @@ -3333,7 +3334,8 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, i_mmap_unlock_read(mapping); out: xas_destroy(&xas); - count_vm_event(!ret ? THP_SPLIT_PAGE : THP_SPLIT_PAGE_FAILED); + if (is_thp) + count_vm_event(!ret ? THP_SPLIT_PAGE : THP_SPLIT_PAGE_FAILED); return ret; }
@@ -3395,7 +3397,8 @@ void deferred_split_folio(struct folio *folio)
spin_lock_irqsave(&ds_queue->split_queue_lock, flags); if (list_empty(&folio->_deferred_list)) { - count_vm_event(THP_DEFERRED_SPLIT_PAGE); + if (folio_test_pmd_mappable(folio)) + count_vm_event(THP_DEFERRED_SPLIT_PAGE); list_add_tail(&folio->_deferred_list, &ds_queue->split_queue); ds_queue->split_queue_len++; #ifdef CONFIG_MEMCG