[PATCH 4.14 07/29] mm: memcontrol: implement lruvec stat functions on top of each other

Greg Kroah-Hartman
2021-01-07T14:32:52Z

From: Johannes Weiner <hannes@cmpxchg.org>

commit 284542656e22c43fdada8c8cc0ca9ede8453eed7 upstream

The implementation of the lruvec stat functions and their variants for
accounting through a page, or accounting from a preemptible context, are
mostly identical and needlessly repetitive.

Implement the lruvec_page functions by looking up the page's lruvec and
then using the lruvec function.

Implement the functions for preemptible contexts by disabling preemption
before calling the atomic context functions.

Link: http://lkml.kernel.org/r/20171103153336.24044-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Shaoying Xu <shaoyi@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/memcontrol.h | 44 ++++++++++++++++++++++----------------------
1 file changed, 22 insertions(+), 22 deletions(-)

--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -569,51 +569,51 @@ static inline void __mod_lruvec_state(st
{
struct mem_cgroup_per_node *pn;

+ /* Update node */
__mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
+
if (mem_cgroup_disabled())
return;
+
pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
+
+ /* Update memcg */
__mod_memcg_state(pn->memcg, idx, val);
+
+ /* Update lruvec */
__this_cpu_add(pn->lruvec_stat->count[idx], val);
}

static inline void mod_lruvec_state(struct lruvec *lruvec,
enum node_stat_item idx, int val)
{
- struct mem_cgroup_per_node *pn;
-
- mod_node_page_state(lruvec_pgdat(lruvec), idx, val);
- if (mem_cgroup_disabled())
- return;
- pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
- mod_memcg_state(pn->memcg, idx, val);
- this_cpu_add(pn->lruvec_stat->count[idx], val);
+ preempt_disable();
+ __mod_lruvec_state(lruvec, idx, val);
+ preempt_enable();
}

static inline void __mod_lruvec_page_state(struct page *page,
enum node_stat_item idx, int val)
{
- struct mem_cgroup_per_node *pn;
+ pg_data_t *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;

- __mod_node_page_state(page_pgdat(page), idx, val);
- if (mem_cgroup_disabled() || !page->mem_cgroup)
+ /* Untracked pages have no memcg, no lruvec. Update only the node */
+ if (!page->mem_cgroup) {
+ __mod_node_page_state(pgdat, idx, val);
return;
- __mod_memcg_state(page->mem_cgroup, idx, val);
- pn = page->mem_cgroup->nodeinfo[page_to_nid(page)];
- __this_cpu_add(pn->lruvec_stat->count[idx], val);
+ }
+
+ lruvec = mem_cgroup_lruvec(pgdat, page->mem_cgroup);
+ __mod_lruvec_state(lruvec, idx, val);
}

static inline void mod_lruvec_page_state(struct page *page,
enum node_stat_item idx, int val)
{
- struct mem_cgroup_per_node *pn;
-
- mod_node_page_state(page_pgdat(page), idx, val);
- if (mem_cgroup_disabled() || !page->mem_cgroup)
- return;
- mod_memcg_state(page->mem_cgroup, idx, val);
- pn = page->mem_cgroup->nodeinfo[page_to_nid(page)];
- this_cpu_add(pn->lruvec_stat->count[idx], val);
+ preempt_disable();
+ __mod_lruvec_page_state(page, idx, val);
+ preempt_enable();
}

unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,