[PATCH] mm: memcontrol: fix slub memory accounting

From: Muchun Song
Date: Tue Feb 23 2021 - 04:27:13 EST


SLUB currently account kmalloc() and kmalloc_node() allocations larger
than order-1 page per-node. But it forget to update the per-memcg
vmstats. So it can lead to inaccurate statistics of "slab_unreclaimable"
which is from memory.stat. Fix it by using mod_lruvec_page_state instead
of mod_node_page_state.

Fixes: 6a486c0ad4dc ("mm, sl[ou]b: improve memory accounting")
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
---
mm/slab_common.c | 4 ++--
mm/slub.c | 8 ++++----
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/slab_common.c b/mm/slab_common.c
index 821f657d38b5..20ffb2b37058 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -906,8 +906,8 @@ void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
page = alloc_pages(flags, order);
if (likely(page)) {
ret = page_address(page);
- mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B,
- PAGE_SIZE << order);
+ mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
+ PAGE_SIZE << order);
}
ret = kasan_kmalloc_large(ret, size, flags);
/* As ret might get tagged, call kmemleak hook after KASAN. */
diff --git a/mm/slub.c b/mm/slub.c
index e564008c2329..f2f953de456e 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4057,8 +4057,8 @@ static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
page = alloc_pages_node(node, flags, order);
if (page) {
ptr = page_address(page);
- mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B,
- PAGE_SIZE << order);
+ mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
+ PAGE_SIZE << order);
}

return kmalloc_large_node_hook(ptr, size, flags);
@@ -4193,8 +4193,8 @@ void kfree(const void *x)

BUG_ON(!PageCompound(page));
kfree_hook(object);
- mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B,
- -(PAGE_SIZE << order));
+ mod_lruvec_page_state(page, NR_SLAB_UNRECLAIMABLE_B,
+ -(PAGE_SIZE << order));
__free_pages(page, order);
return;
}
--
2.11.0