diff options
| -rw-r--r-- | include/linux/mm_inline.h | 2 | ||||
| -rw-r--r-- | mm/memcontrol.c | 24 |
2 files changed, 21 insertions, 5 deletions
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index 712e8c37a200..d8cea81ab1ac 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -35,8 +35,8 @@ static __always_inline void del_page_from_lru_list(struct page *page, struct lruvec *lruvec, enum lru_list lru) { int nr_pages = hpage_nr_pages(page); - mem_cgroup_update_lru_size(lruvec, lru, -nr_pages); list_del(&page->lru); + mem_cgroup_update_lru_size(lruvec, lru, -nr_pages); __mod_zone_page_state(lruvec_zone(lruvec), NR_LRU_BASE + lru, -nr_pages); } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 011dac8ab5d7..6a0199706f00 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1023,22 +1023,38 @@ out: * @lru: index of lru list the page is sitting on * @nr_pages: positive when adding or negative when removing * - * This function must be called when a page is added to or removed from an - * lru list. + * This function must be called under lru_lock, just before a page is added + * to or just after a page is removed from an lru list (that ordering being + * so as to allow it to check that lru_size 0 is consistent with list_empty). */ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, int nr_pages) { struct mem_cgroup_per_zone *mz; unsigned long *lru_size; + long size; + bool empty; if (mem_cgroup_disabled()) return; mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec); lru_size = mz->lru_size + lru; - *lru_size += nr_pages; - VM_BUG_ON((long)(*lru_size) < 0); + empty = list_empty(lruvec->lists + lru); + + if (nr_pages < 0) + *lru_size += nr_pages; + + size = *lru_size; + if (WARN_ONCE(size < 0 || empty != !size, + "%s(%p, %d, %d): lru_size %ld but %sempty\n", + __func__, lruvec, lru, nr_pages, size, empty ? "" : "not ")) { + VM_BUG_ON(1); + *lru_size = 0; + } + + if (nr_pages > 0) + *lru_size += nr_pages; } bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) |