diff options
| author | Johannes Weiner <hannes@cmpxchg.org> | 2019-11-30 17:55:34 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-12-01 12:59:06 -0800 |
| commit | 867e5e1de14b2b2bde324cdfeec3f3f83eb21424 (patch) | |
| tree | 22a8f8e2142314de860983c95d89fbe86b39cf1a /mm/memcontrol.c | |
| parent | de3b01506ea494b46aab05dc143b69adbf2aaa9d (diff) | |
| download | linux-867e5e1de14b2b2bde324cdfeec3f3f83eb21424.tar.bz2 | |
mm: clean up and clarify lruvec lookup procedure
There is a per-memcg lruvec and a NUMA node lruvec. Which one is being
used is somewhat confusing right now, and it's easy to make mistakes -
especially when it comes to global reclaim.
How it works: when memory cgroups are enabled, we always use the
root_mem_cgroup's per-node lruvecs. When memory cgroups are not compiled
in or disabled at runtime, we use pgdat->lruvec.
Document that in a comment.
Due to the way the reclaim code is generalized, all lookups use the
mem_cgroup_lruvec() helper function, and nobody should have to find the
right lruvec manually right now. But to avoid future mistakes, rename the
pgdat->lruvec member to pgdat->__lruvec and delete the convenience wrapper
that suggests it's a commonly accessed member.
While in this area, swap the mem_cgroup_lruvec() argument order. The name
suggests a memcg operation, yet it takes a pgdat first and a memcg second.
I have to double take every time I call this. Fix that.
Link: http://lkml.kernel.org/r/20191022144803.302233-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 529e12a59131..bc01423277c5 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -777,7 +777,7 @@ void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val) if (!memcg || memcg == root_mem_cgroup) { __mod_node_page_state(pgdat, idx, val); } else { - lruvec = mem_cgroup_lruvec(pgdat, memcg); + lruvec = mem_cgroup_lruvec(memcg, pgdat); __mod_lruvec_state(lruvec, idx, val); } rcu_read_unlock(); @@ -1221,7 +1221,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd struct lruvec *lruvec; if (mem_cgroup_disabled()) { - lruvec = &pgdat->lruvec; + lruvec = &pgdat->__lruvec; goto out; } @@ -3634,7 +3634,7 @@ static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, int nid, unsigned int lru_mask) { - struct lruvec *lruvec = mem_cgroup_lruvec(NODE_DATA(nid), memcg); + struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); unsigned long nr = 0; enum lru_list lru; @@ -5338,8 +5338,8 @@ static int mem_cgroup_move_account(struct page *page, anon = PageAnon(page); pgdat = page_pgdat(page); - from_vec = mem_cgroup_lruvec(pgdat, from); - to_vec = mem_cgroup_lruvec(pgdat, to); + from_vec = mem_cgroup_lruvec(from, pgdat); + to_vec = mem_cgroup_lruvec(to, pgdat); spin_lock_irqsave(&from->move_lock, flags); |