mlock: fix unevictable_pgs event counts on THP
5.8 commit 5d91f31faf8e ("mm: swap: fix vmstats for huge page") has
established that vm_events should count every subpage of a THP, including
unevictable_pgs_culled and unevictable_pgs_rescued; but
lru_cache_add_inactive_or_unevictable() was not doing so for
unevictable_pgs_mlocked, and mm/mlock.c was not doing so for
unevictable_pgs mlocked, munlocked, cleared and stranded.
Fix them; but THPs don't go the pagevec way in mlock.c, so no fixes needed
on that path.
Fixes: 5d91f31faf8e ("mm: swap: fix vmstats for huge page")
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Yang Shi <shy828301@gmail.com>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008301408230.5954@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swap.c b/mm/swap.c
index d16d65d..e7bdf09 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -494,14 +494,14 @@ void lru_cache_add_inactive_or_unevictable(struct page *page,
unevictable = (vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) == VM_LOCKED;
if (unlikely(unevictable) && !TestSetPageMlocked(page)) {
+ int nr_pages = thp_nr_pages(page);
/*
* We use the irq-unsafe __mod_zone_page_stat because this
* counter is not modified from interrupt context, and the pte
* lock is held(spinlock), which implies preemption disabled.
*/
- __mod_zone_page_state(page_zone(page), NR_MLOCK,
- thp_nr_pages(page));
- count_vm_event(UNEVICTABLE_PGMLOCKED);
+ __mod_zone_page_state(page_zone(page), NR_MLOCK, nr_pages);
+ count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages);
}
lru_cache_add(page);
}
