diff options
| author | Baolin Wang <[email protected]> | 2024-08-20 17:49:14 +0800 |
|---|---|---|
| committer | Andrew Morton <[email protected]> | 2024-09-03 21:15:39 -0700 |
| commit | d6b8f296e8d74d685627fd746558745c13b8bd32 (patch) | |
| tree | 4d236b8fc8c4431d0f3570d7bf60b18663367cb6 | |
| parent | fda6d4de064a9d37414df36d45836898fff5e165 (diff) | |
mm: khugepaged: use the number of pages in the folio to check the reference count
Use the number of pages in the folio to check the reference count as
preparation for supporting shmem mTHP collapse.
Link: https://lkml.kernel.org/r/9ea49262308de28957596cc6e8edc2d3a4f54659.1724140601.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <[email protected]>
Acked-by: David Hildenbrand <[email protected]>
Cc: Barry Song <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Zi Yan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
| -rw-r--r-- | mm/khugepaged.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index 76f05215ee87..e015c94eba09 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1988,9 +1988,9 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, VM_BUG_ON_FOLIO(folio != xa_load(xas.xa, index), folio); /* - * We control three references to the folio: + * We control 2 + nr_pages references to the folio: * - we hold a pin on it; - * - one reference from page cache; + * - nr_pages reference from page cache; * - one from lru_isolate_folio; * If those are the only references, then any new usage * of the folio will have to fetch it from the page @@ -1998,7 +1998,7 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, * truncate, so any new usage will be blocked until we * unlock folio after collapse/during rollback. */ - if (folio_ref_count(folio) != 3) { + if (folio_ref_count(folio) != 2 + folio_nr_pages(folio)) { result = SCAN_PAGE_COUNT; xas_unlock_irq(&xas); folio_putback_lru(folio); @@ -2181,7 +2181,7 @@ immap_locked: folio_clear_active(folio); folio_clear_unevictable(folio); folio_unlock(folio); - folio_put_refs(folio, 3); + folio_put_refs(folio, 2 + folio_nr_pages(folio)); } goto out; |