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 --- include/linux/memcontrol.h | 44 ++++++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 2c80b69dd266..1ffc54ac4cc9 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -569,51 +569,51 @@ static inline void __mod_lruvec_state(struct lruvec *lruvec, { 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,