diff options
| -rw-r--r-- | include/linux/page_cgroup.h | 5 | ||||
| -rw-r--r-- | mm/memcontrol.c | 66 |
2 files changed, 29 insertions, 42 deletions
diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h index 363bbc8..6b63679 100644 --- a/include/linux/page_cgroup.h +++ b/include/linux/page_cgroup.h @@ -99,11 +99,6 @@ static inline void unlock_page_cgroup(struct page_cgroup *pc) bit_spin_unlock(PCG_LOCK, &pc->flags); } -static inline int page_is_cgroup_locked(struct page_cgroup *pc) -{ - return bit_spin_is_locked(PCG_LOCK, &pc->flags); -} - static inline void move_lock_page_cgroup(struct page_cgroup *pc, unsigned long *flags) { diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2881c9e..e9d33dc 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2200,33 +2200,49 @@ void mem_cgroup_split_huge_fixup(struct page *head, struct page *tail) #endif /** - * __mem_cgroup_move_account - move account of the page + * mem_cgroup_move_account - move account of the page * @pc: page_cgroup of the page. * @from: mem_cgroup which the page is moved from. * @to: mem_cgroup which the page is moved to. @from != @to. * @uncharge: whether we should call uncharge and css_put against @from. + * @charge_size: number of bytes to charge (regular or huge page) * * The caller must confirm following. * - page is not on LRU (isolate_page() is useful.) - * - the pc is locked, used, and ->mem_cgroup points to @from. + * - compound_lock is held when charge_size > PAGE_SIZE * * This function doesn't do "charge" nor css_get to new cgroup. It should be * done by a caller(__mem_cgroup_try_charge would be usefull). If @uncharge is * true, this function does "uncharge" from old cgroup, but it doesn't if * @uncharge is false, so a caller should do "uncharge". */ - -static void __mem_cgroup_move_account(struct page_cgroup *pc, - struct mem_cgroup *from, struct mem_cgroup *to, bool uncharge, - int charge_size) +static int mem_cgroup_move_account(struct page_cgroup *pc, + struct mem_cgroup *from, struct mem_cgroup *to, + bool uncharge, int charge_size) { int nr_pages = charge_size >> PAGE_SHIFT; + unsigned long flags; + int ret; VM_BUG_ON(from == to); VM_BUG_ON(PageLRU(pc->page)); - VM_BUG_ON(!page_is_cgroup_locked(pc)); - VM_BUG_ON(!PageCgroupUsed(pc)); - VM_BUG_ON(pc->mem_cgroup != from); + /* + * The page is isolated from LRU. So, collapse function + * will not handle this page. But page splitting can happen. + * Do this check under compound_page_lock(). The caller should + * hold it. + */ + ret = -EBUSY; + if (charge_size > PAGE_SIZE && !PageTransHuge(pc->page)) + goto out; + + lock_page_cgroup(pc); + + ret = -EINVAL; + if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) + goto unlock; + + move_lock_page_cgroup(pc, &flags); if (PageCgroupFileMapped(pc)) { /* Update mapped_file data for mem_cgroup */ @@ -2250,40 +2266,16 @@ static void __mem_cgroup_move_account(struct page_cgroup *pc, * garanteed that "to" is never removed. So, we don't check rmdir * status here. */ -} - -/* - * check whether the @pc is valid for moving account and call - * __mem_cgroup_move_account() - */ -static int mem_cgroup_move_account(struct page_cgroup *pc, - struct mem_cgroup *from, struct mem_cgroup *to, - bool uncharge, int charge_size) -{ - int ret = -EINVAL; - unsigned long flags; - /* - * The page is isolated from LRU. So, collapse function - * will not handle this page. But page splitting can happen. - * Do this check under compound_page_lock(). The caller should - * hold it. - */ - if ((charge_size > PAGE_SIZE) && !PageTransHuge(pc->page)) - return -EBUSY; - - lock_page_cgroup(pc); - if (PageCgroupUsed(pc) && pc->mem_cgroup == from) { - move_lock_page_cgroup(pc, &flags); - __mem_cgroup_move_account(pc, from, to, uncharge, charge_size); - move_unlock_page_cgroup(pc, &flags); - ret = 0; - } + move_unlock_page_cgroup(pc, &flags); + ret = 0; +unlock: unlock_page_cgroup(pc); /* * check events */ memcg_check_events(to, pc->page); memcg_check_events(from, pc->page); +out: return ret; } |