The API for page_remove_rmap() needs to be page-based, because we can
remove mappings of pages individually. But inside the function, we want
to only call compound_head() once and then use the folio APIs instead
of the page APIs that each call compound_head().
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
mm/rmap.c | 51 ++++++++++++++++++++++++++++-----------------------
1 file changed, 28 insertions(+), 23 deletions(-)
diff --git a/mm/rmap.c b/mm/rmap.c
index 17984eb9f990..7d51ed49ee9f 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1378,42 +1378,42 @@ void page_add_file_rmap(struct page *page,
*
* The caller needs to hold the pte lock.
*/
-void page_remove_rmap(struct page *page,
- struct vm_area_struct *vma, bool compound)
+void page_remove_rmap(struct page *page, struct vm_area_struct *vma,
+ bool compound)
{
- atomic_t *mapped;
+ struct folio *folio = page_folio(page);
+ atomic_t *mapped = &folio->_nr_pages_mapped;
int nr = 0, nr_pmdmapped = 0;
bool last;
+ enum node_stat_item idx;
VM_BUG_ON_PAGE(compound && !PageHead(page), page);
/* Hugetlb pages are not counted in NR_*MAPPED */
- if (unlikely(PageHuge(page))) {
+ if (unlikely(folio_test_hugetlb(folio))) {
/* hugetlb pages are always mapped with pmds */
- atomic_dec(compound_mapcount_ptr(page));
+ atomic_dec(&folio->_entire_mapcount);
return;
}
- lock_page_memcg(page);
+ folio_memcg_lock(folio);
/* Is page being unmapped by PTE? Is this its last map to be removed? */
if (likely(!compound)) {
last = atomic_add_negative(-1, &page->_mapcount);
nr = last;
- if (last && PageCompound(page)) {
- mapped = subpages_mapcount_ptr(compound_head(page));
+ if (last && folio_test_large(folio)) {
nr = atomic_dec_return_relaxed(mapped);
nr = (nr < COMPOUND_MAPPED);
}
- } else if (PageTransHuge(page)) {
+ } else if (folio_test_large(folio)) {
/* That test is redundant: it's for safety or to optimize out */
- last = atomic_add_negative(-1, compound_mapcount_ptr(page));
+ last = atomic_add_negative(-1, &folio->_entire_mapcount);
if (last) {
- mapped = subpages_mapcount_ptr(page);
nr = atomic_sub_return_relaxed(COMPOUND_MAPPED, mapped);
if (likely(nr < COMPOUND_MAPPED)) {
- nr_pmdmapped = thp_nr_pages(page);
+ nr_pmdmapped = folio_nr_pages(folio);
nr = nr_pmdmapped - (nr & FOLIO_PAGES_MAPPED);
/* Raced ahead of another remove and an add? */
if (unlikely(nr < 0))
@@ -1426,21 +1426,26 @@ void page_remove_rmap(struct page *page,
}
if (nr_pmdmapped) {
- __mod_lruvec_page_state(page, PageAnon(page) ? NR_ANON_THPS :
- (PageSwapBacked(page) ? NR_SHMEM_PMDMAPPED :
- NR_FILE_PMDMAPPED), -nr_pmdmapped);
+ if (folio_test_anon(folio))
+ idx = NR_ANON_THPS;
+ else if (folio_test_swapbacked(folio))
+ idx = NR_SHMEM_PMDMAPPED;
+ else
+ idx = NR_FILE_PMDMAPPED;
+ __lruvec_stat_mod_folio(folio, idx, -nr_pmdmapped);
}
if (nr) {
- __mod_lruvec_page_state(page, PageAnon(page) ? NR_ANON_MAPPED :
- NR_FILE_MAPPED, -nr);
+ idx = folio_test_anon(folio) ? NR_ANON_MAPPED : NR_FILE_MAPPED;
+ __lruvec_stat_mod_folio(folio, idx, -nr);
+
/*
- * Queue anon THP for deferred split if at least one small
- * page of the compound page is unmapped, but at least one
- * small page is still mapped.
+ * Queue anon THP for deferred split if at least one
+ * page of the folio is unmapped, but at least one
+ * page is still mapped.
*/
- if (PageTransCompound(page) && PageAnon(page))
+ if (folio_test_large(folio) && folio_test_anon(folio))
if (!compound || nr < nr_pmdmapped)
- deferred_split_huge_page(compound_head(page));
+ deferred_split_huge_page(&folio->page);
}
/*
@@ -1451,7 +1456,7 @@ void page_remove_rmap(struct page *page,
* and remember that it's only reliable while mapped.
*/
- unlock_page_memcg(page);
+ folio_memcg_unlock(folio);
munlock_vma_page(page, vma, compound);
}
--
2.35.1
