diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/debug.c | 4 | ||||
| -rw-r--r-- | mm/hugetlb.c | 4 | ||||
| -rw-r--r-- | mm/internal.h | 18 | ||||
| -rw-r--r-- | mm/rmap.c | 9 |
4 files changed, 27 insertions, 8 deletions
diff --git a/mm/debug.c b/mm/debug.c index 893c9dbf76ca..8e58e8dab0b2 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -94,10 +94,10 @@ static void __dump_page(struct page *page) page, page_ref_count(head), mapcount, mapping, page_to_pgoff(page), page_to_pfn(page)); if (compound) { - pr_warn("head:%p order:%u compound_mapcount:%d subpages_mapcount:%d pincount:%d\n", + pr_warn("head:%p order:%u compound_mapcount:%d nr_pages_mapped:%d pincount:%d\n", head, compound_order(head), head_compound_mapcount(head), - head_subpages_mapcount(head), + folio_nr_pages_mapped(folio), atomic_read(&folio->_pincount)); } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 15b2707c1600..c9702224931c 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1475,7 +1475,7 @@ static void __destroy_compound_gigantic_folio(struct folio *folio, struct page *p; atomic_set(folio_mapcount_ptr(folio), 0); - atomic_set(folio_subpages_mapcount_ptr(folio), 0); + atomic_set(&folio->_nr_pages_mapped, 0); atomic_set(&folio->_pincount, 0); for (i = 1; i < nr_pages; i++) { @@ -1997,7 +1997,7 @@ static bool __prep_compound_gigantic_folio(struct folio *folio, set_compound_head(p, &folio->page); } atomic_set(folio_mapcount_ptr(folio), -1); - atomic_set(folio_subpages_mapcount_ptr(folio), 0); + atomic_set(&folio->_nr_pages_mapped, 0); atomic_set(&folio->_pincount, 0); return true; diff --git a/mm/internal.h b/mm/internal.h index 1d6f4e168510..583e15357e09 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -52,6 +52,24 @@ struct folio_batch; void page_writeback_init(void); +/* + * If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages, + * its nr_pages_mapped would be 0x400000: choose the COMPOUND_MAPPED bit + * above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently + * leaves nr_pages_mapped at 0, but avoid surprise if it participates later. + */ +#define COMPOUND_MAPPED 0x800000 +#define FOLIO_PAGES_MAPPED (COMPOUND_MAPPED - 1) + +/* + * How many individual pages have an elevated _mapcount. Excludes + * the folio's entire_mapcount. + */ +static inline int folio_nr_pages_mapped(struct folio *folio) +{ + return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED; +} + static inline void *folio_raw_mapping(struct folio *folio) { unsigned long mapping = (unsigned long)folio->mapping; diff --git a/mm/rmap.c b/mm/rmap.c index 6ccd42bbae93..b573472b4ac3 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1080,12 +1080,13 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff, int total_compound_mapcount(struct page *head) { + struct folio *folio = (struct folio *)head; int mapcount = head_compound_mapcount(head); int nr_subpages; int i; /* In the common case, avoid the loop when no subpages mapped by PTE */ - if (head_subpages_mapcount(head) == 0) + if (folio_nr_pages_mapped(folio) == 0) return mapcount; /* * Add all the PTE mappings of those subpages mapped by PTE. @@ -1233,7 +1234,7 @@ void page_add_anon_rmap(struct page *page, nr = atomic_add_return_relaxed(COMPOUND_MAPPED, mapped); if (likely(nr < COMPOUND_MAPPED + COMPOUND_MAPPED)) { nr_pmdmapped = thp_nr_pages(page); - nr = nr_pmdmapped - (nr & SUBPAGES_MAPPED); + nr = nr_pmdmapped - (nr & FOLIO_PAGES_MAPPED); /* Raced ahead of a remove and another add? */ if (unlikely(nr < 0)) nr = 0; @@ -1337,7 +1338,7 @@ void page_add_file_rmap(struct page *page, nr = atomic_add_return_relaxed(COMPOUND_MAPPED, mapped); if (likely(nr < COMPOUND_MAPPED + COMPOUND_MAPPED)) { nr_pmdmapped = thp_nr_pages(page); - nr = nr_pmdmapped - (nr & SUBPAGES_MAPPED); + nr = nr_pmdmapped - (nr & FOLIO_PAGES_MAPPED); /* Raced ahead of a remove and another add? */ if (unlikely(nr < 0)) nr = 0; @@ -1399,7 +1400,7 @@ void page_remove_rmap(struct page *page, nr = atomic_sub_return_relaxed(COMPOUND_MAPPED, mapped); if (likely(nr < COMPOUND_MAPPED)) { nr_pmdmapped = thp_nr_pages(page); - nr = nr_pmdmapped - (nr & SUBPAGES_MAPPED); + nr = nr_pmdmapped - (nr & FOLIO_PAGES_MAPPED); /* Raced ahead of another remove and an add? */ if (unlikely(nr < 0)) nr = 0; |