summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--mm/rmap.c31
1 files changed, 14 insertions, 17 deletions
diff --git a/mm/rmap.c b/mm/rmap.c
index 615b5d323ee2..ee1f10df984d 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1236,14 +1236,14 @@ void page_add_new_anon_rmap(struct page *page,
void page_add_file_rmap(struct page *page,
struct vm_area_struct *vma, bool compound)
{
- int i, nr = 1;
+ int i, nr = 0;
VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page);
lock_page_memcg(page);
if (compound && PageTransHuge(page)) {
int nr_pages = thp_nr_pages(page);
- for (i = 0, nr = 0; i < nr_pages; i++) {
+ for (i = 0; i < nr_pages; i++) {
if (atomic_inc_and_test(&page[i]._mapcount))
nr++;
}
@@ -1271,11 +1271,12 @@ void page_add_file_rmap(struct page *page,
VM_WARN_ON_ONCE(!PageLocked(page));
SetPageDoubleMap(compound_head(page));
}
- if (!atomic_inc_and_test(&page->_mapcount))
- goto out;
+ if (atomic_inc_and_test(&page->_mapcount))
+ nr++;
}
- __mod_lruvec_page_state(page, NR_FILE_MAPPED, nr);
out:
+ if (nr)
+ __mod_lruvec_page_state(page, NR_FILE_MAPPED, nr);
unlock_page_memcg(page);
mlock_vma_page(page, vma, compound);
@@ -1283,7 +1284,7 @@ out:
static void page_remove_file_rmap(struct page *page, bool compound)
{
- int i, nr = 1;
+ int i, nr = 0;
VM_BUG_ON_PAGE(compound && !PageHead(page), page);
@@ -1298,12 +1299,12 @@ static void page_remove_file_rmap(struct page *page, bool compound)
if (compound && PageTransHuge(page)) {
int nr_pages = thp_nr_pages(page);
- for (i = 0, nr = 0; i < nr_pages; i++) {
+ for (i = 0; i < nr_pages; i++) {
if (atomic_add_negative(-1, &page[i]._mapcount))
nr++;
}
if (!atomic_add_negative(-1, compound_mapcount_ptr(page)))
- return;
+ goto out;
if (PageSwapBacked(page))
__mod_lruvec_page_state(page, NR_SHMEM_PMDMAPPED,
-nr_pages);
@@ -1311,16 +1312,12 @@ static void page_remove_file_rmap(struct page *page, bool compound)
__mod_lruvec_page_state(page, NR_FILE_PMDMAPPED,
-nr_pages);
} else {
- if (!atomic_add_negative(-1, &page->_mapcount))
- return;
+ if (atomic_add_negative(-1, &page->_mapcount))
+ nr++;
}
-
- /*
- * We use the irq-unsafe __{inc|mod}_lruvec_page_state because
- * these counters are not modified in interrupt context, and
- * pte lock(a spinlock) is held, which implies preemption disabled.
- */
- __mod_lruvec_page_state(page, NR_FILE_MAPPED, -nr);
+out:
+ if (nr)
+ __mod_lruvec_page_state(page, NR_FILE_MAPPED, -nr);
}
static void page_remove_anon_compound_rmap(struct page *page)