From fa9add641b1b1c564db916accac1db346e7a2759 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Tue, 29 May 2012 15:07:09 -0700 Subject: mm/memcg: apply add/del_page to lruvec Take lruvec further: pass it instead of zone to add_page_to_lru_list() and del_page_from_lru_list(); and pagevec_lru_move_fn() pass lruvec down to its target functions. This cleanup eliminates a swathe of cruft in memcontrol.c, including mem_cgroup_lru_add_list(), mem_cgroup_lru_del_list() and mem_cgroup_lru_move_lists() - which never actually touched the lists. In their place, mem_cgroup_page_lruvec() to decide the lruvec, previously a side-effect of add, and mem_cgroup_update_lru_size() to maintain the lru_size stats. Whilst these are simplifications in their own right, the goal is to bring the evaluation of lruvec next to the spin_locking of the lrus, in preparation for a future patch. Signed-off-by: Hugh Dickins Cc: KOSAKI Motohiro Acked-by: KAMEZAWA Hiroyuki Acked-by: Michal Hocko Acked-by: Konstantin Khlebnikov Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 101 ++++++++++++++------------------------------------------ 1 file changed, 24 insertions(+), 77 deletions(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 75198dac3fe8..bb8d7d3cf302 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1035,7 +1035,7 @@ EXPORT_SYMBOL(mem_cgroup_count_vm_event); /** * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg * @zone: zone of the wanted lruvec - * @mem: memcg of the wanted lruvec + * @memcg: memcg of the wanted lruvec * * Returns the lru list vector holding pages for the given @zone and * @mem. This can be the global zone lruvec, if the memory controller @@ -1068,19 +1068,11 @@ struct lruvec *mem_cgroup_zone_lruvec(struct zone *zone, */ /** - * mem_cgroup_lru_add_list - account for adding an lru page and return lruvec - * @zone: zone of the page + * mem_cgroup_page_lruvec - return lruvec for adding an lru page * @page: the page - * @lru: current lru - * - * This function accounts for @page being added to @lru, and returns - * the lruvec for the given @zone and the memcg @page is charged to. - * - * The callsite is then responsible for physically linking the page to - * the returned lruvec->lists[@lru]. + * @zone: zone of the page */ -struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, - enum lru_list lru) +struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone) { struct mem_cgroup_per_zone *mz; struct mem_cgroup *memcg; @@ -1093,7 +1085,7 @@ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, memcg = pc->mem_cgroup; /* - * Surreptitiously switch any uncharged page to root: + * Surreptitiously switch any uncharged offlist page to root: * an uncharged page off lru does nothing to secure * its former mem_cgroup from sudden removal. * @@ -1101,65 +1093,35 @@ struct lruvec *mem_cgroup_lru_add_list(struct zone *zone, struct page *page, * under page_cgroup lock: between them, they make all uses * of pc->mem_cgroup safe. */ - if (!PageCgroupUsed(pc) && memcg != root_mem_cgroup) + if (!PageLRU(page) && !PageCgroupUsed(pc) && memcg != root_mem_cgroup) pc->mem_cgroup = memcg = root_mem_cgroup; mz = page_cgroup_zoneinfo(memcg, page); - /* compound_order() is stabilized through lru_lock */ - mz->lru_size[lru] += 1 << compound_order(page); return &mz->lruvec; } /** - * mem_cgroup_lru_del_list - account for removing an lru page - * @page: the page - * @lru: target lru + * mem_cgroup_update_lru_size - account for adding or removing an lru page + * @lruvec: mem_cgroup per zone lru vector + * @lru: index of lru list the page is sitting on + * @nr_pages: positive when adding or negative when removing * - * This function accounts for @page being removed from @lru. - * - * The callsite is then responsible for physically unlinking - * @page->lru. + * This function must be called when a page is added to or removed from an + * lru list. */ -void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru) +void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, + int nr_pages) { struct mem_cgroup_per_zone *mz; - struct mem_cgroup *memcg; - struct page_cgroup *pc; + unsigned long *lru_size; if (mem_cgroup_disabled()) return; - pc = lookup_page_cgroup(page); - memcg = pc->mem_cgroup; - VM_BUG_ON(!memcg); - mz = page_cgroup_zoneinfo(memcg, page); - /* huge page split is done under lru_lock. so, we have no races. */ - VM_BUG_ON(mz->lru_size[lru] < (1 << compound_order(page))); - mz->lru_size[lru] -= 1 << compound_order(page); -} - -/** - * mem_cgroup_lru_move_lists - account for moving a page between lrus - * @zone: zone of the page - * @page: the page - * @from: current lru - * @to: target lru - * - * This function accounts for @page being moved between the lrus @from - * and @to, and returns the lruvec for the given @zone and the memcg - * @page is charged to. - * - * The callsite is then responsible for physically relinking - * @page->lru to the returned lruvec->lists[@to]. - */ -struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone, - struct page *page, - enum lru_list from, - enum lru_list to) -{ - /* XXX: Optimize this, especially for @from == @to */ - mem_cgroup_lru_del_list(page, from); - return mem_cgroup_lru_add_list(zone, page, to); + 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); } /* @@ -1252,24 +1214,6 @@ int mem_cgroup_inactive_file_is_low(struct lruvec *lruvec) return (active > inactive); } -struct zone_reclaim_stat * -mem_cgroup_get_reclaim_stat_from_page(struct page *page) -{ - struct page_cgroup *pc; - struct mem_cgroup_per_zone *mz; - - if (mem_cgroup_disabled()) - return NULL; - - pc = lookup_page_cgroup(page); - if (!PageCgroupUsed(pc)) - return NULL; - /* Ensure pc->mem_cgroup is visible after reading PCG_USED. */ - smp_rmb(); - mz = page_cgroup_zoneinfo(pc->mem_cgroup, page); - return &mz->lruvec.reclaim_stat; -} - #define mem_cgroup_from_res_counter(counter, member) \ container_of(counter, struct mem_cgroup, member) @@ -2509,6 +2453,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, { struct page_cgroup *pc = lookup_page_cgroup(page); struct zone *uninitialized_var(zone); + struct lruvec *lruvec; bool was_on_lru = false; bool anon; @@ -2531,8 +2476,9 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, zone = page_zone(page); spin_lock_irq(&zone->lru_lock); if (PageLRU(page)) { + lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup); ClearPageLRU(page); - del_page_from_lru_list(zone, page, page_lru(page)); + del_page_from_lru_list(page, lruvec, page_lru(page)); was_on_lru = true; } } @@ -2550,9 +2496,10 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, if (lrucare) { if (was_on_lru) { + lruvec = mem_cgroup_zone_lruvec(zone, pc->mem_cgroup); VM_BUG_ON(PageLRU(page)); SetPageLRU(page); - add_page_to_lru_list(zone, page, page_lru(page)); + add_page_to_lru_list(page, lruvec, page_lru(page)); } spin_unlock_irq(&zone->lru_lock); } -- cgit v1.2.3-59-g8ed1b