diff options
Diffstat (limited to 'mm/khugepaged.c')
| -rw-r--r-- | mm/khugepaged.c | 35 |
1 files changed, 19 insertions, 16 deletions
diff --git a/mm/khugepaged.c b/mm/khugepaged.c index cdf5a581368b..15203ea7d007 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -548,19 +548,6 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte, } } -static bool is_refcount_suitable(struct folio *folio) -{ - int expected_refcount = folio_mapcount(folio); - - if (!folio_test_anon(folio) || folio_test_swapcache(folio)) - expected_refcount += folio_nr_pages(folio); - - if (folio_test_private(folio)) - expected_refcount++; - - return folio_ref_count(folio) == expected_refcount; -} - static int __collapse_huge_page_isolate(struct vm_area_struct *vma, unsigned long address, pte_t *pte, @@ -652,7 +639,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, * but not from this process. The other process cannot write to * the page, only trigger CoW. */ - if (!is_refcount_suitable(folio)) { + if (folio_expected_ref_count(folio) != folio_ref_count(folio)) { folio_unlock(folio); result = SCAN_PAGE_COUNT; goto out; @@ -1402,7 +1389,7 @@ static int hpage_collapse_scan_pmd(struct mm_struct *mm, * has excessive GUP pins (i.e. 512). Anyway the same check * will be done again later the risk seems low. */ - if (!is_refcount_suitable(folio)) { + if (folio_expected_ref_count(folio) != folio_ref_count(folio)) { result = SCAN_PAGE_COUNT; goto out_unmap; } @@ -2293,6 +2280,17 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr, continue; } + if (!folio_try_get(folio)) { + xas_reset(&xas); + continue; + } + + if (unlikely(folio != xas_reload(&xas))) { + folio_put(folio); + xas_reset(&xas); + continue; + } + if (folio_order(folio) == HPAGE_PMD_ORDER && folio->index == start) { /* Maybe PMD-mapped */ @@ -2303,23 +2301,27 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr, * it's safe to skip LRU and refcount checks before * returning. */ + folio_put(folio); break; } node = folio_nid(folio); if (hpage_collapse_scan_abort(node, cc)) { result = SCAN_SCAN_ABORT; + folio_put(folio); break; } cc->node_load[node]++; if (!folio_test_lru(folio)) { result = SCAN_PAGE_LRU; + folio_put(folio); break; } - if (!is_refcount_suitable(folio)) { + if (folio_expected_ref_count(folio) + 1 != folio_ref_count(folio)) { result = SCAN_PAGE_COUNT; + folio_put(folio); break; } @@ -2331,6 +2333,7 @@ static int hpage_collapse_scan_file(struct mm_struct *mm, unsigned long addr, */ present += folio_nr_pages(folio); + folio_put(folio); if (need_resched()) { xas_pause(&xas); |