diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 18:34:42 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-12-10 18:34:42 -0800 |
commit | b6da0076bab5a12afb19312ffee41c95490af2a0 (patch) | |
tree | 52a5675b9c2ff95d88b981d5b9a3822f6073c112 /mm/memcontrol.c | |
parent | cbfe0de303a55ed96d8831c2d5f56f8131cd6612 (diff) | |
parent | a53b831549141aa060a8b54b76e3a42870d74cc0 (diff) |
Merge branch 'akpm' (patchbomb from Andrew)
Merge first patchbomb from Andrew Morton:
- a few minor cifs fixes
- dma-debug upadtes
- ocfs2
- slab
- about half of MM
- procfs
- kernel/exit.c
- panic.c tweaks
- printk upates
- lib/ updates
- checkpatch updates
- fs/binfmt updates
- the drivers/rtc tree
- nilfs
- kmod fixes
- more kernel/exit.c
- various other misc tweaks and fixes
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
exit: pidns: fix/update the comments in zap_pid_ns_processes()
exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
exit: exit_notify: re-use "dead" list to autoreap current
exit: reparent: call forget_original_parent() under tasklist_lock
exit: reparent: avoid find_new_reaper() if no children
exit: reparent: introduce find_alive_thread()
exit: reparent: introduce find_child_reaper()
exit: reparent: document the ->has_child_subreaper checks
exit: reparent: s/while_each_thread/for_each_thread/ in find_new_reaper()
exit: reparent: fix the cross-namespace PR_SET_CHILD_SUBREAPER reparenting
exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting
exit: proc: don't try to flush /proc/tgid/task/tgid
exit: release_task: fix the comment about group leader accounting
exit: wait: drop tasklist_lock before psig->c* accounting
exit: wait: don't use zombie->real_parent
exit: wait: cleanup the ptrace_reparented() checks
usermodehelper: kill the kmod_thread_locker logic
usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper()
fs/hfs/catalog.c: fix comparison bug in hfs_cat_keycmp
nilfs2: fix the nilfs_iget() vs. nilfs_new_inode() races
...
Diffstat (limited to 'mm/memcontrol.c')
-rw-r--r-- | mm/memcontrol.c | 1706 |
1 files changed, 505 insertions, 1201 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ee48428cf8e3..85df503ec023 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -25,7 +25,7 @@ * GNU General Public License for more details. */ -#include <linux/res_counter.h> +#include <linux/page_counter.h> #include <linux/memcontrol.h> #include <linux/cgroup.h> #include <linux/mm.h> @@ -51,7 +51,7 @@ #include <linux/seq_file.h> #include <linux/vmpressure.h> #include <linux/mm_inline.h> -#include <linux/page_cgroup.h> +#include <linux/swap_cgroup.h> #include <linux/cpu.h> #include <linux/oom.h> #include <linux/lockdep.h> @@ -143,14 +143,8 @@ struct mem_cgroup_stat_cpu { unsigned long targets[MEM_CGROUP_NTARGETS]; }; -struct mem_cgroup_reclaim_iter { - /* - * last scanned hierarchy member. Valid only if last_dead_count - * matches memcg->dead_count of the hierarchy root group. - */ - struct mem_cgroup *last_visited; - int last_dead_count; - +struct reclaim_iter { + struct mem_cgroup *position; /* scan generation, increased every round-trip */ unsigned int generation; }; @@ -162,10 +156,10 @@ struct mem_cgroup_per_zone { struct lruvec lruvec; unsigned long lru_size[NR_LRU_LISTS]; - struct mem_cgroup_reclaim_iter reclaim_iter[DEF_PRIORITY + 1]; + struct reclaim_iter iter[DEF_PRIORITY + 1]; struct rb_node tree_node; /* RB tree node */ - unsigned long long usage_in_excess;/* Set to the value by which */ + unsigned long usage_in_excess;/* Set to the value by which */ /* the soft limit is exceeded*/ bool on_tree; struct mem_cgroup *memcg; /* Back pointer, we cannot */ @@ -198,7 +192,7 @@ static struct mem_cgroup_tree soft_limit_tree __read_mostly; struct mem_cgroup_threshold { struct eventfd_ctx *eventfd; - u64 threshold; + unsigned long threshold; }; /* For threshold */ @@ -284,10 +278,13 @@ static void mem_cgroup_oom_notify(struct mem_cgroup *memcg); */ struct mem_cgroup { struct cgroup_subsys_state css; - /* - * the counter to account for memory usage - */ - struct res_counter res; + + /* Accounted resources */ + struct page_counter memory; + struct page_counter memsw; + struct page_counter kmem; + + unsigned long soft_limit; /* vmpressure notifications */ struct vmpressure vmpressure; @@ -296,15 +293,6 @@ struct mem_cgroup { int initialized; /* - * the counter to account for mem+swap usage. - */ - struct res_counter memsw; - - /* - * the counter to account for kernel memory usage. - */ - struct res_counter kmem; - /* * Should the accounting and control be hierarchical, per subtree? */ bool use_hierarchy; @@ -352,7 +340,6 @@ struct mem_cgroup { struct mem_cgroup_stat_cpu nocpu_base; spinlock_t pcp_counter_lock; - atomic_t dead_count; #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_INET) struct cg_proto tcp_mem; #endif @@ -382,7 +369,6 @@ struct mem_cgroup { /* internal only representation about the status of kmem accounting. */ enum { KMEM_ACCOUNTED_ACTIVE, /* accounted by this cgroup itself */ - KMEM_ACCOUNTED_DEAD, /* dead memcg with pending kmem charges */ }; #ifdef CONFIG_MEMCG_KMEM @@ -396,22 +382,6 @@ static bool memcg_kmem_is_active(struct mem_cgroup *memcg) return test_bit(KMEM_ACCOUNTED_ACTIVE, &memcg->kmem_account_flags); } -static void memcg_kmem_mark_dead(struct mem_cgroup *memcg) -{ - /* - * Our caller must use css_get() first, because memcg_uncharge_kmem() - * will call css_put() if it sees the memcg is dead. - */ - smp_wmb(); - if (test_bit(KMEM_ACCOUNTED_ACTIVE, &memcg->kmem_account_flags)) - set_bit(KMEM_ACCOUNTED_DEAD, &memcg->kmem_account_flags); -} - -static bool memcg_kmem_test_and_clear_dead(struct mem_cgroup *memcg) -{ - return test_and_clear_bit(KMEM_ACCOUNTED_DEAD, - &memcg->kmem_account_flags); -} #endif /* Stuffs for move charges at task migration. */ @@ -650,7 +620,7 @@ static void disarm_kmem_keys(struct mem_cgroup *memcg) * This check can't live in kmem destruction function, * since the charges will outlive the cgroup */ - WARN_ON(res_counter_read_u64(&memcg->kmem, RES_USAGE) != 0); + WARN_ON(page_counter_read(&memcg->kmem)); } #else static void disarm_kmem_keys(struct mem_cgroup *memcg) @@ -664,8 +634,6 @@ static void disarm_static_keys(struct mem_cgroup *memcg) disarm_kmem_keys(memcg); } -static void drain_all_stock_async(struct mem_cgroup *memcg); - static struct mem_cgroup_per_zone * mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone) { @@ -706,7 +674,7 @@ soft_limit_tree_from_page(struct page *page) static void __mem_cgroup_insert_exceeded(struct mem_cgroup_per_zone *mz, struct mem_cgroup_tree_per_zone *mctz, - unsigned long long new_usage_in_excess) + unsigned long new_usage_in_excess) { struct rb_node **p = &mctz->rb_root.rb_node; struct rb_node *parent = NULL; @@ -755,10 +723,21 @@ static void mem_cgroup_remove_exceeded(struct mem_cgroup_per_zone *mz, spin_unlock_irqrestore(&mctz->lock, flags); } +static unsigned long soft_limit_excess(struct mem_cgroup *memcg) +{ + unsigned long nr_pages = page_counter_read(&memcg->memory); + unsigned long soft_limit = ACCESS_ONCE(memcg->soft_limit); + unsigned long excess = 0; + + if (nr_pages > soft_limit) + excess = nr_pages - soft_limit; + + return excess; +} static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) { - unsigned long long excess; + unsigned long excess; struct mem_cgroup_per_zone *mz; struct mem_cgroup_tree_per_zone *mctz; @@ -769,7 +748,7 @@ static void mem_cgroup_update_tree(struct mem_cgroup *memcg, struct page *page) */ for (; memcg; memcg = parent_mem_cgroup(memcg)) { mz = mem_cgroup_page_zoneinfo(memcg, page); - excess = res_counter_soft_limit_excess(&memcg->res); + excess = soft_limit_excess(memcg); /* * We have to update the tree if mz is on RB-tree or * mem is over its softlimit. @@ -825,7 +804,7 @@ retry: * position in the tree. */ __mem_cgroup_remove_exceeded(mz, mctz); - if (!res_counter_soft_limit_excess(&mz->memcg->res) || + if (!soft_limit_excess(mz->memcg) || !css_tryget_online(&mz->memcg->css)) goto retry; done: @@ -1062,122 +1041,6 @@ static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) return memcg; } -/* - * Returns a next (in a pre-order walk) alive memcg (with elevated css - * ref. count) or NULL if the whole root's subtree has been visited. - * - * helper function to be used by mem_cgroup_iter - */ -static struct mem_cgroup *__mem_cgroup_iter_next(struct mem_cgroup *root, - struct mem_cgroup *last_visited) -{ - struct cgroup_subsys_state *prev_css, *next_css; - - prev_css = last_visited ? &last_visited->css : NULL; -skip_node: - next_css = css_next_descendant_pre(prev_css, &root->css); - - /* - * Even if we found a group we have to make sure it is - * alive. css && !memcg means that the groups should be - * skipped and we should continue the tree walk. - * last_visited css is safe to use because it is - * protected by css_get and the tree walk is rcu safe. - * - * We do not take a reference on the root of the tree walk - * because we might race with the root removal when it would - * be the only node in the iterated hierarchy and mem_cgroup_iter - * would end up in an endless loop because it expects that at - * least one valid node will be returned. Root cannot disappear - * because caller of the iterator should hold it already so - * skipping css reference should be safe. - */ - if (next_css) { - struct mem_cgroup *memcg = mem_cgroup_from_css(next_css); - - if (next_css == &root->css) - return memcg; - - if (css_tryget_online(next_css)) { - /* - * Make sure the memcg is initialized: - * mem_cgroup_css_online() orders the the - * initialization against setting the flag. - */ - if (smp_load_acquire(&memcg->initialized)) - return memcg; - css_put(next_css); - } - - prev_css = next_css; - goto skip_node; - } - - return NULL; -} - -static void mem_cgroup_iter_invalidate(struct mem_cgroup *root) -{ - /* - * When a group in the hierarchy below root is destroyed, the - * hierarchy iterator can no longer be trusted since it might - * have pointed to the destroyed group. Invalidate it. - */ - atomic_inc(&root->dead_count); -} - -static struct mem_cgroup * -mem_cgroup_iter_load(struct mem_cgroup_reclaim_iter *iter, - struct mem_cgroup *root, - int *sequence) -{ - struct mem_cgroup *position = NULL; - /* - * A cgroup destruction happens in two stages: offlining and - * release. They are separated by a RCU grace period. - * - * If the iterator is valid, we may still race with an - * offlining. The RCU lock ensures the object won't be - * released, tryget will fail if we lost the race. - */ - *sequence = atomic_read(&root->dead_count); - if (iter->last_dead_count == *sequence) { - smp_rmb(); - position = iter->last_visited; - - /* - * We cannot take a reference to root because we might race - * with root removal and returning NULL would end up in - * an endless loop on the iterator user level when root - * would be returned all the time. - */ - if (position && position != root && - !css_tryget_online(&position->css)) - position = NULL; - } - return position; -} - -static void mem_cgroup_iter_update(struct mem_cgroup_reclaim_iter *iter, - struct mem_cgroup *last_visited, - struct mem_cgroup *new_position, - struct mem_cgroup *root, - int sequence) -{ - /* root reference counting symmetric to mem_cgroup_iter_load */ - if (last_visited && last_visited != root) - css_put(&last_visited->css); - /* - * We store the sequence count from the time @last_visited was - * loaded successfully instead of rereading it here so that we - * don't lose destruction events in between. We could have - * raced with the destruction of @new_position after all. - */ - iter->last_visited = new_position; - smp_wmb(); - iter->last_dead_count = sequence; -} - /** * mem_cgroup_iter - iterate over memory cgroup hierarchy * @root: hierarchy root @@ -1199,8 +1062,10 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, struct mem_cgroup *prev, struct mem_cgroup_reclaim_cookie *reclaim) { + struct reclaim_iter *uninitialized_var(iter); + struct cgroup_subsys_state *css = NULL; struct mem_cgroup *memcg = NULL; - struct mem_cgroup *last_visited = NULL; + struct mem_cgroup *pos = NULL; if (mem_cgroup_disabled()) return NULL; @@ -1209,50 +1074,101 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root, root = root_mem_cgroup; if (prev && !reclaim) - last_visited = prev; + pos = prev; if (!root->use_hierarchy && root != root_mem_cgroup) { if (prev) - goto out_css_put; + goto out; return root; } rcu_read_lock(); - while (!memcg) { - struct mem_cgroup_reclaim_iter *uninitialized_var(iter); - int uninitialized_var(seq); - - if (reclaim) { - struct mem_cgroup_per_zone *mz; - - mz = mem_cgroup_zone_zoneinfo(root, reclaim->zone); - iter = &mz->reclaim_iter[reclaim->priority]; - if (prev && reclaim->generation != iter->generation) { - iter->last_visited = NULL; - goto out_unlock; - } - last_visited = mem_cgroup_iter_load(iter, root, &seq); + if (reclaim) { + struct mem_cgroup_per_zone *mz; + + mz = mem_cgroup_zone_zoneinfo(root, reclaim->zone); + iter = &mz->iter[reclaim->priority]; + + if (prev && reclaim->generation != iter->generation) + goto out_unlock; + + do { + pos = ACCESS_ONCE(iter->position); + /* + * A racing update may change the position and + * put the last reference, hence css_tryget(), + * or retry to see the updated position. + */ + } while (pos && !css_tryget(&pos->css)); + } + + if (pos) + css = &pos->css; + + for (;;) { + css = css_next_descendant_pre(css, &root->css); + if (!css) { + /* + * Reclaimers share the hierarchy walk, and a + * new one might jump in right at the end of + * the hierarchy - make sure they see at least + * one group and restart from the beginning. + */ + if (!prev) + continue; + break; } - memcg = __mem_cgroup_iter_next(root, last_visited); + /* + * Verify the css and acquire a reference. The root + * is provided by the caller, so we know it's alive + * and kicking, and don't take an extra reference. + */ + memcg = mem_cgroup_from_css(css); + + if (css == &root->css) + break; - if (reclaim) { - mem_cgroup_iter_update(iter, last_visited, memcg, root, - seq); + if (css_tryget(css)) { + /* + * Make sure the memcg is initialized: + * mem_cgroup_css_online() orders the the + * initialization against setting the flag. + */ + if (smp_load_acquire(&memcg->initialized)) + break; - if (!memcg) - iter->generation++; - else if (!prev && memcg) - reclaim->generation = iter->generation; + css_put(css); } - if (prev && !memcg) - goto out_unlock; + memcg = NULL; + } + + if (reclaim) { + if (cmpxchg(&iter->position, pos, memcg) == pos) { + if (memcg) + css_get(&memcg->css); + if (pos) + css_put(&pos->css); + } + + /* + * pairs with css_tryget when dereferencing iter->position + * above. + */ + if (pos) + css_put(&pos->css); + + if (!memcg) + iter->generation++; + else if (!prev) + reclaim->generation = iter->generation; } + out_unlock: rcu_read_unlock(); -out_css_put: +out: if (prev && prev != root) css_put(&prev->css); @@ -1346,15 +1262,18 @@ out: } /** - * mem_cgroup_page_lruvec - return lruvec for adding an lru page + * mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page * @page: the page * @zone: zone of the page + * + * This function is only safe when following the LRU page isolation + * and putback protocol: the LRU lock must be held, and the page must + * either be PageLRU() or the caller must have isolated/allocated it. */ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone) { struct mem_cgroup_per_zone *mz; struct mem_cgroup *memcg; - struct page_cgroup *pc; struct lruvec *lruvec; if (mem_cgroup_disabled()) { @@ -1362,20 +1281,13 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct zone *zone) goto out; } - pc = lookup_page_cgroup(page); - memcg = pc->mem_cgroup; - + memcg = page->mem_cgroup; /* - * Surreptitiously switch any uncharged offlist page to root: - * an uncharged page off lru does nothing to secure - * its former mem_cgroup from sudden removal. - * - * Our caller holds lru_lock, and PageCgroupUsed is updated - * under page_cgroup lock: between them, they make all uses - * of pc->mem_cgroup safe. + * Swapcache readahead pages are added to the LRU - and + * possibly migrated - before they are charged. */ - if (!PageLRU(page) && !PageCgroupUsed(pc) && memcg != root_mem_cgroup) - pc->mem_cgroup = memcg = root_mem_cgroup; + if (!memcg) + memcg = root_mem_cgroup; mz = mem_cgroup_page_zoneinfo(memcg, page); lruvec = &mz->lruvec; @@ -1414,41 +1326,24 @@ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, VM_BUG_ON((long)(*lru_size) < 0); } -/* - * Checks whether given mem is same or in the root_mem_cgroup's - * hierarchy subtree - */ -bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, - struct mem_cgroup *memcg) +bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, struct mem_cgroup *root) { - if (root_memcg == memcg) + if (root == memcg) return true; - if (!root_memcg->use_hierarchy || !memcg) + if (!root->use_hierarchy) return false; - return cgroup_is_descendant(memcg->css.cgroup, root_memcg->css.cgroup); -} - -static bool mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg, - struct mem_cgroup *memcg) -{ - bool ret; - - rcu_read_lock(); - ret = __mem_cgroup_same_or_subtree(root_memcg, memcg); - rcu_read_unlock(); - return ret; + return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup); } -bool task_in_mem_cgroup(struct task_struct *task, - const struct mem_cgroup *memcg) +bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) { - struct mem_cgroup *curr = NULL; + struct mem_cgroup *task_memcg; struct task_struct *p; bool ret; p = find_lock_task_mm(task); if (p) { - curr = get_mem_cgroup_from_mm(p->mm); + task_memcg = get_mem_cgroup_from_mm(p->mm); task_unlock(p); } else { /* @@ -1457,19 +1352,12 @@ bool task_in_mem_cgroup(struct task_struct *task, * killed to prevent needlessly killing additional tasks. */ rcu_read_lock(); - curr = mem_cgroup_from_task(task); - if (curr) - css_get(&curr->css); + task_memcg = mem_cgroup_from_task(task); + css_get(&task_memcg->css); rcu_read_unlock(); } - /* - * We should check use_hierarchy of "memcg" not "curr". Because checking - * use_hierarchy of "curr" here make this function true if hierarchy is - * enabled in "curr" and "curr" is a child of "memcg" in *cgroup* - * hierarchy(even if use_hierarchy is disabled in "memcg"). - */ - ret = mem_cgroup_same_or_subtree(memcg, curr); - css_put(&curr->css); + ret = mem_cgroup_is_descendant(task_memcg, memcg); + css_put(&task_memcg->css); return ret; } @@ -1492,7 +1380,7 @@ int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec) return inactive * inactive_ratio < active; } -#define mem_cgroup_from_res_counter(counter, member) \ +#define mem_cgroup_from_counter(counter, member) \ container_of(counter, struct mem_cgroup, member) /** @@ -1504,12 +1392,23 @@ int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec) */ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) { - unsigned long long margin; + unsigned long margin = 0; + unsigned long count; + unsigned long limit; - margin = res_counter_margin(&memcg->res); - if (do_swap_account) - margin = min(margin, res_counter_margin(&memcg->memsw)); - return margin >> PAGE_SHIFT; + count = page_counter_read(&memcg->memory); + limit = ACCESS_ONCE(memcg->memory.limit); + if (count < limit) + margin = limit - count; + + if (do_swap_account) { + count = page_counter_read(&memcg->memsw); + limit = ACCESS_ONCE(memcg->memsw.limit); + if (count <= limit) + margin = min(margin, limit - count); + } + + return margin; } int mem_cgroup_swappiness(struct mem_cgroup *memcg) @@ -1522,37 +1421,6 @@ int mem_cgroup_swappiness(struct mem_cgroup *memcg) } /* - * memcg->moving_account is used for checking possibility that some thread is - * calling move_account(). When a thread on CPU-A starts moving pages under - * a memcg, other threads should check memcg->moving_account under - * rcu_read_lock(), like this: - * - * CPU-A CPU-B - * rcu_read_lock() - * memcg->moving_account+1 if (memcg->mocing_account) - * take heavy locks. - * synchronize_rcu() update something. - * rcu_read_unlock() - * start move here. - */ - -static void mem_cgroup_start_move(struct mem_cgroup *memcg) -{ - atomic_inc(&memcg->moving_account); - synchronize_rcu(); -} - -static void mem_cgroup_end_move(struct mem_cgroup *memcg) -{ - /* - * Now, mem_cgroup_clear_mc() may call this function with NULL. - * We check NULL in callee rather than caller. - */ - if (memcg) - atomic_dec(&memcg->moving_account); -} - -/* * A routine for checking "mem" is under move_account() or not. * * Checking a cgroup is mc.from or mc.to or under hierarchy of @@ -1574,8 +1442,8 @@ static bool mem_cgroup_under_move(struct mem_cgroup *memcg) if (!from) goto unlock; - ret = mem_cgroup_same_or_subtree(memcg, from) - || mem_cgroup_same_or_subtree(memcg, to); + ret = mem_cgroup_is_descendant(from, memcg) || + mem_cgroup_is_descendant(to, memcg); unlock: spin_unlock(&mc.lock); return ret; @@ -1597,23 +1465,6 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) return false; } -/* - * Take this lock when - * - a code tries to modify page's memcg while it's USED. - * - a code tries to modify page state accounting in a memcg. - */ -static void move_lock_mem_cgroup(struct mem_cgroup *memcg, - unsigned long *flags) -{ - spin_lock_irqsave(&memcg->move_lock, *flags); -} - -static void move_unlock_mem_cgroup(struct mem_cgroup *memcg, - unsigned long *flags) -{ - spin_unlock_irqrestore(&memcg->move_lock, *flags); -} - #define K(x) ((x) << (PAGE_SHIFT-10)) /** * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. @@ -1644,18 +1495,15 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p) rcu_read_unlock(); - pr_info("memory: usage %llukB, limit %llukB, failcnt %llu\n", - res_counter_read_u64(&memcg->res, RES_USAGE) >> 10, - res_counter_read_u64(&memcg->res, RES_LIMIT) >> 10, - res_counter_read_u64(&memcg->res, RES_FAILCNT)); - pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %llu\n", - res_counter_read_u64(&memcg->memsw, RES_USAGE) >> 10, - res_counter_read_u64(&memcg->memsw, RES_LIMIT) >> 10, - res_counter_read_u64(&memcg->memsw, RES_FAILCNT)); - pr_info("kmem: usage %llukB, limit %llukB, failcnt %llu\n", - res_counter_read_u64(&memcg->kmem, RES_USAGE) >> 10, - res_counter_read_u64(&memcg->kmem, RES_LIMIT) >> 10, - res_counter_read_u64(&memcg->kmem, RES_FAILCNT)); + pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", + K((u64)page_counter_read(&memcg->memory)), + K((u64)memcg->memory.limit), memcg->memory.failcnt); + pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", + K((u64)page_counter_read(&memcg->memsw)), + K((u64)memcg->memsw.limit), memcg->memsw.failcnt); + pr_info("kmem: usage %llukB, limit %llukB, failcnt %lu\n", + K((u64)page_counter_read(&memcg->kmem)), + K((u64)memcg->kmem.limit), memcg->kmem.failcnt); for_each_mem_cgroup_tree(iter, memcg) { pr_info("Memory cgroup stats for "); @@ -1695,28 +1543,17 @@ static int mem_cgroup_count_children(struct mem_cgroup *memcg) /* * Return the memory (and swap, if configured) limit for a memcg. */ -static u64 mem_cgroup_get_limit(struct mem_cgroup *memcg) +static unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg) { - u64 limit; - - limit = res_counter_read_u64(&memcg->res, RES_LIMIT); + unsigned long limit; - /* - * Do not consider swap space if we cannot swap due to swappiness - */ + limit = memcg->memory.limit; if (mem_cgroup_swappiness(memcg)) { - u64 memsw; + unsigned long memsw_limit; - limit += total_swap_pages << PAGE_SHIFT; - memsw = res_counter_read_u64(&memcg->memsw, RES_LIMIT); - - /* - * If memsw is finite and limits the amount of swap space - * available to this memcg, return that limit. - */ - limit = min(limit, memsw); + memsw_limit = memcg->memsw.limit; + limit = min(limit + total_swap_pages, memsw_limit); } - return limit; } @@ -1740,7 +1577,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, } check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL); - totalpages = mem_cgroup_get_limit(memcg) >> PAGE_SHIFT ? : 1; + totalpages = mem_cgroup_get_limit(memcg) ? : 1; for_each_mem_cgroup_tree(iter, memcg) { struct css_task_iter it; struct task_struct *task; @@ -1880,52 +1717,11 @@ int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) memcg->last_scanned_node = node; return node; } - -/* - * Check all nodes whether it contains reclaimable pages or not. - * For quick scan, we make use of scan_nodes. This will allow us to skip - * unused nodes. But scan_nodes is lazily updated and may not cotain - * enough new information. We need to do double check. - */ -static bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) -{ - int nid; - - /* - * quick check...making use of scan_node. - * We can skip unused nodes. - */ - if (!nodes_empty(memcg->scan_nodes)) { - for (nid = first_node(memcg->scan_nodes); - nid < MAX_NUMNODES; - nid = next_node(nid, memcg->scan_nodes)) { - - if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) - return true; - } - } - /* - * Check rest of nodes. - */ - for_each_node_state(nid, N_MEMORY) { - if (node_isset(nid, memcg->scan_nodes)) - continue; - if (test_mem_cgroup_node_reclaimable(memcg, nid, noswap)) - return true; - } - return false; -} - #else int mem_cgroup_select_victim_node(struct mem_cgroup *memcg) { return 0; } - -static bool mem_cgroup_reclaimable(struct mem_cgroup *memcg, bool noswap) -{ - return test_mem_cgroup_node_reclaimable(memcg, 0, noswap); -} #endif static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, @@ -1943,7 +1739,7 @@ static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, .priority = 0, }; - excess = res_counter_soft_limit_excess(&root_memcg->res) >> PAGE_SHIFT; + excess = soft_limit_excess(root_memcg); while (1) { victim = mem_cgroup_iter(root_memcg, victim, &reclaim); @@ -1969,12 +1765,10 @@ static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg, } continue; } - if (!mem_cgroup_reclaimable(victim, false)) - continue; total += mem_cgroup_shrink_node_zone(victim, gfp_mask, false, zone, &nr_scanned); *total_scanned += nr_scanned; - if (!res_counter_soft_limit_excess(&root_memcg->res)) + if (!soft_limit_excess(root_memcg)) break; } mem_cgroup_iter_break(root_memcg, victim); @@ -2081,12 +1875,8 @@ static int memcg_oom_wake_function(wait_queue_t *wait, oom_wait_info = container_of(wait, struct oom_wait_info, wait); oom_wait_memcg = oom_wait_info->memcg; - /* - * Both of oom_wait_info->memcg and wake_memcg are stable under us. - * Then we can use css_is_ancestor without taking care of RCU. - */ - if (!mem_cgroup_same_or_subtree(oom_wait_memcg, wake_memcg) - && !mem_cgroup_same_or_subtree(wake_memcg, oom_wait_memcg)) + if (!mem_cgroup_is_descendant(wake_memcg, oom_wait_memcg) && + !mem_cgroup_is_descendant(oom_wait_memcg, wake_memcg)) return 0; return autoremove_wake_function(wait, mode, sync, arg); } @@ -2228,26 +2018,23 @@ struct mem_cgroup *mem_cgroup_begin_page_stat(struct page *page, unsigned long *flags) { struct mem_cgroup *memcg; - struct page_cgroup *pc; rcu_read_lock(); if (mem_cgroup_disabled()) return NULL; - - pc = lookup_page_cgroup(page); again: - memcg = pc->mem_cgroup; - if (unlikely(!memcg || !PageCgroupUsed(pc))) + memcg = page->mem_cgroup; + if (unlikely(!memcg)) return NULL; *locked = false; if (atomic_read(&memcg->moving_account) <= 0) return memcg; - move_lock_mem_cgroup(memcg, flags); - if (memcg != pc->mem_cgroup || !PageCgroupUsed(pc)) { - move_unlock_mem_cgroup(memcg, flags); + spin_lock_irqsave(&memcg->move_lock, *flags); + if (memcg != page->mem_cgroup) { + spin_unlock_irqrestore(&memcg->move_lock, *flags); goto again; } *locked = true; @@ -2261,11 +2048,11 @@ again: * @locked: value received from mem_cgroup_begin_page_stat() * @flags: value received from mem_cgroup_begin_page_stat() */ -void mem_cgroup_end_page_stat(struct mem_cgroup *memcg, bool locked, - unsigned long flags) +void mem_cgroup_end_page_stat(struct mem_cgroup *memcg, bool *locked, + unsigned long *flags) { - if (memcg && locked) - move_unlock_mem_cgroup(memcg, &flags); + if (memcg && *locked) + spin_unlock_irqrestore(&memcg->move_lock, *flags); rcu_read_unlock(); } @@ -2316,33 +2103,32 @@ static DEFINE_MUTEX(percpu_charge_mutex); static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { struct memcg_stock_pcp *stock; - bool ret = true; + bool ret = false; if (nr_pages > CHARGE_BATCH) - return false; + return ret; stock = &get_cpu_var(memcg_stock); - if (memcg == stock->cached && stock->nr_pages >= nr_pages) + if (memcg == stock->cached && stock->nr_pages >= nr_pages) { stock->nr_pages -= nr_pages; - else /* need to call res_counter_charge */ - ret = false; + ret = true; + } put_cpu_var(memcg_stock); return ret; } /* - * Returns stocks cached in percpu to res_counter and reset cached information. + * Returns stocks cached in percpu and reset cached information. */ static void drain_stock(struct memcg_stock_pcp *stock) { struct mem_cgroup *old = stock->cached; if (stock->nr_pages) { - unsigned long bytes = stock->nr_pages * PAGE_SIZE; - - res_counter_uncharge(&old->res, bytes); + page_counter_uncharge(&old->memory, stock->nr_pages); if (do_swap_account) - res_counter_uncharge(&old->memsw, bytes); + page_counter_uncharge(&old->memsw, stock->nr_pages); + css_put_many(&old->css, stock->nr_pages); stock->nr_pages = 0; } stock->cached = NULL; @@ -2371,7 +2157,7 @@ static void __init memcg_stock_init(void) } /* - * Cache charges(val) which is from res_counter, to local per_cpu area. + * Cache charges(val) to local per_cpu area. * This will be consumed by consume_stock() function, later. */ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) @@ -2388,13 +2174,15 @@ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) /* * Drains all per-CPU charge caches for given root_memcg resp. subtree - * of the hierarchy under it. sync flag says whether we should block - * until the work is done. + * of the hierarchy under it. */ -static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) +static void drain_all_stock(struct mem_cgroup *root_memcg) { int cpu, curcpu; + /* If someone's already draining, avoid adding running more workers. */ + if (!mutex_trylock(&percpu_charge_mutex)) + return; /* Notify other cpus that system-wide "drain" is running */ get_online_cpus(); curcpu = get_cpu(); @@ -2405,7 +2193,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) memcg = stock->cached; if (!memcg || !stock->nr_pages) continue; - if (!mem_cgroup_same_or_subtree(root_memcg, memcg)) + if (!mem_cgroup_is_descendant(memcg, root_memcg)) continue; if (!test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { if (cpu == curcpu) @@ -2415,42 +2203,7 @@ static void drain_all_stock(struct mem_cgroup *root_memcg, bool sync) } } put_cpu(); - - if (!sync) - goto out; - - for_each_online_cpu(cpu) { - struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); - if (test_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) - flush_work(&stock->work); - } -out: put_online_cpus(); -} - -/* - * Tries to drain stocked charges in other cpus. This function is asynchronous - * and just put a work per cpu for draining localy on each cpu. Caller can - * expects some charges will be back to res_counter later but cannot wait for - * it. - */ -static void drain_all_stock_async(struct mem_cgroup *root_memcg) -{ - /* - * If someone calls draining, avoid adding more kworker runs. - */ - if (!mutex_trylock(&percpu_charge_mutex)) - return; - drain_all_stock(root_memcg, false); - mutex_unlock(&percpu_charge_mutex); -} - -/* This is a synchronous drain interface. */ -static void drain_all_stock_sync(struct mem_cgroup *root_memcg) -{ - /* called when force_empty is called */ - mutex_lock(&percpu_charge_mutex); - drain_all_stock(root_memcg, true); mutex_unlock(&percpu_charge_mutex); } @@ -2506,9 +2259,8 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, unsigned int batch = max(CHARGE_BATCH, nr_pages); int nr_retries = MEM_CGROUP_RECLAIM_RETRIES; struct mem_cgroup *mem_over_limit; - struct res_counter *fail_res; + struct page_counter *counter; unsigned long nr_reclaimed; - unsigned long long size; bool may_swap = true; bool drained = false; int ret = 0; @@ -2519,16 +2271,15 @@ retry: if (consume_stock(memcg, nr_pages)) goto done; - size = batch * PAGE_SIZE; if (!do_swap_account || - !res_counter_charge(&memcg->memsw, size, &fail_res)) { - if (!res_counter_charge(&memcg->res, size, &fail_res)) + !page_counter_try_charge(&memcg->memsw, batch, &counter)) { + if (!page_counter_try_charge(&memcg->memory, batch, &counter)) goto done_restock; if (do_swap_account) - res_counter_uncharge(&memcg->memsw, size); - mem_over_limit = mem_cgroup_from_res_counter(fail_res, res); + page_counter_uncharge(&memcg->memsw, batch); + mem_over_limit = mem_cgroup_from_counter(counter, memory); } else { - mem_over_limit = mem_cgroup_from_res_counter(fail_res, memsw); + mem_over_limit = mem_cgroup_from_counter(counter, memsw); may_swap = false; } @@ -2561,7 +2312,7 @@ retry: goto retry; if (!drained) { - drain_all_stock_async(mem_over_limit); + drain_all_stock(mem_over_limit); drained = true; goto retry; } @@ -2603,6 +2354,7 @@ bypass: return -EINTR; done_restock: + css_get_many(&memcg->css, batch); if (batch > nr_pages) refill_stock(memcg, batch - nr_pages); done: @@ -2611,32 +2363,14 @@ done: static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) { - unsigned long bytes = nr_pages * PAGE_SIZE; - if (mem_cgroup_is_root(memcg)) return; - res_counter_uncharge(&memcg->res, bytes); + page_counter_uncharge(&memcg->memory, nr_pages); if (do_swap_account) - res_counter_uncharge(&memcg->memsw, bytes); -} - -/* - * Cancel chrages in this cgroup....doesn't propagate to parent cgroup. - * This is useful when moving usage to parent cgroup. - */ -static void __mem_cgroup_cancel_local_charge(struct mem_cgroup *memcg, - unsigned int nr_pages) -{ - unsigned long bytes = nr_pages * PAGE_SIZE; - - if (mem_cgroup_is_root(memcg)) - return; + page_counter_uncharge(&memcg->memsw, nr_pages); - res_counter_uncharge_until(&memcg->res, memcg->res.parent, bytes); - if (do_swap_account) - res_counter_uncharge_until(&memcg->memsw, - memcg->memsw.parent, bytes); + css_put_many(&memcg->css, nr_pages); } /* @@ -2665,17 +2399,15 @@ static struct mem_cgroup *mem_cgroup_lookup(unsigned short id) */ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page) { - struct mem_cgroup *memcg = NULL; - struct page_cgroup *pc; + struct mem_cgroup *memcg; unsigned short id; swp_entry_t ent; VM_BUG_ON_PAGE(!PageLocked(page), page); - pc = lookup_page_cgroup(page); - if (PageCgroupUsed(pc)) { - memcg = pc->mem_cgroup; - if (memcg && !css_tryget_online(&memcg->css)) + memcg = page->mem_cgroup; + if (memcg) { + if (!css_tryget_online(&memcg->css)) memcg = NULL; } else if (PageSwapCache(page)) { ent.val = page_private(page); @@ -2723,14 +2455,9 @@ static void unlock_page_lru(struct page *page, int isolated) static void commit_charge(struct page *page, struct mem_cgroup *memcg, bool lrucare) { - struct page_cgroup *pc = lookup_page_cgroup(page); int isolated; - VM_BUG_ON_PAGE(PageCgroupUsed(pc), page); - /* - * we don't need page_cgroup_lock about tail pages, becase they are not - * accessed by any other context at this point. - */ + VM_BUG_ON_PAGE(page->mem_cgroup, page); /* * In some cases, SwapCache and FUSE(splice_buf->radixtree), the page @@ -2741,7 +2468,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg, /* * Nobody should be changing or seriously looking at - * pc->mem_cgroup and pc->flags at this point: + * page->mem_cgroup at this point: * * - the page is uncharged * @@ -2753,15 +2480,12 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg, * - a page cache insertion, a swapin fault, or a migration * have the page locked */ - pc->mem_cgroup = memcg; - pc->flags = PCG_USED | PCG_MEM | (do_swap_account ? PCG_MEMSW : 0); + page->mem_cgroup = memcg; if (lrucare) unlock_page_lru(page, isolated); } -static DEFINE_MUTEX(set_limit_mutex); - #ifdef CONFIG_MEMCG_KMEM /* * The memcg_slab_mutex is held whenever a per memcg kmem cache is created or @@ -2769,8 +2493,6 @@ static DEFINE_MUTEX(set_limit_mutex); */ static DEFINE_MUTEX(memcg_slab_mutex); -static DEFINE_MUTEX(activate_kmem_mutex); - /* * This is a bit cumbersome, but it is rarely used and avoids a backpointer * in the memcg_cache_params struct. @@ -2784,36 +2506,17 @@ static struct kmem_cache *memcg_params_to_cache(struct memcg_cache_params *p) return cache_from_memcg_idx(cachep, memcg_cache_id(p->memcg)); } -#ifdef CONFIG_SLABINFO -static int mem_cgroup_slabinfo_read(struct seq_file *m, void *v) -{ - struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); - struct memcg_cache_params *params; - - if (!memcg_kmem_is_active(memcg)) - return -EIO; - - print_slabinfo_header(m); - - mutex_lock(&memcg_slab_mutex); - list_for_each_entry(params, &memcg->memcg_slab_caches, list) - cache_show(memcg_params_to_cache(params), m); - mutex_unlock(&memcg_slab_mutex); - - return 0; -} -#endif - -static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size) +static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, + unsigned long nr_pages) { - struct res_counter *fail_res; + struct page_counter *counter; int ret = 0; - ret = res_counter_charge(&memcg->kmem, size, &fail_res); - if (ret) + ret = page_counter_try_charge(&memcg->kmem, nr_pages, &counter); + if (ret < 0) return ret; - ret = try_charge(memcg, gfp, size >> PAGE_SHIFT); + ret = try_charge(memcg, gfp, nr_pages); if (ret == -EINTR) { /* * try_charge() chose to bypass to root due to OOM kill or @@ -2830,37 +2533,27 @@ static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size) * when the allocation triggers should have been already * directed to the root cgroup in memcontrol.h */ - res_counter_charge_nofail(&memcg->res, size, &fail_res); + page_counter_charge(&memcg->memory, nr_pages); if (do_swap_account) - res_counter_charge_nofail(&memcg->memsw, size, - &fail_res); + page_counter_charge(&memcg->memsw, nr_pages); + css_get_many(&memcg->css, nr_pages); ret = 0; } else if (ret) - res_counter_uncharge(&memcg->kmem, size); + page_counter_uncharge(&memcg->kmem, nr_pages); return ret; } -static void memcg_uncharge_kmem(struct mem_cgroup *memcg, u64 size) +static void memcg_uncharge_kmem(struct mem_cgroup *memcg, + unsigned long nr_pages) { - res_counter_uncharge(&memcg->res, size); + page_counter_uncharge(&memcg->memory, nr_pages); if (do_swap_account) - res_counter_uncharge(&memcg->memsw, size); + page_counter_uncharge(&memcg->memsw, nr_pages); - /* Not down to 0 */ - if (res_counter_uncharge(&memcg->kmem, size)) - return; + page_counter_uncharge(&memcg->kmem, nr_pages); - /* - * Releases a reference taken in kmem_cgroup_css_offline in case - * this last uncharge is racing with the offlining code or it is - * outliving the memcg existence. - * - * The memory barrier imposed by test&clear is paired with the - * explicit one in memcg_kmem_mark_dead(). - */ - if (memcg_kmem_test_and_clear_dead(memcg)) - css_put(&memcg->css); + css_put_many(&memcg->css, nr_pages); } /* @@ -3124,19 +2817,21 @@ static void memcg_schedule_register_cache(struct mem_cgroup *memcg, int __memcg_charge_slab(struct kmem_cache *cachep, gfp_t gfp, int order) { + unsigned int nr_pages = 1 << order; int res; - res = memcg_charge_kmem(cachep->memcg_params->memcg, gfp, - PAGE_SIZE << order); + res = memcg_charge_kmem(cachep->memcg_params->memcg, gfp, nr_pages); if (!res) - atomic_add(1 << order, &cachep->memcg_params->nr_pages); + atomic_add(nr_pages, &cachep->memcg_params->nr_pages); return res; } void __memcg_uncharge_slab(struct kmem_cache *cachep, int order) { - memcg_uncharge_kmem(cachep->memcg_params->memcg, PAGE_SIZE << order); - atomic_sub(1 << order, &cachep->memcg_params->nr_pages); + unsigned int nr_pages = 1 << order; + + memcg_uncharge_kmem(cachep->memcg_params->memcg, nr_pages); + atomic_sub(nr_pages, &cachep->memcg_params->nr_pages); } /* @@ -3257,7 +2952,7 @@ __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **_memcg, int order) return true; } - ret = memcg_charge_kmem(memcg, gfp, PAGE_SIZE << order); + ret = memcg_charge_kmem(memcg, gfp, 1 << order); if (!ret) *_memcg = memcg; @@ -3268,46 +2963,27 @@ __memcg_kmem_newpage_charge(gfp_t gfp, struct mem_cgroup **_memcg, int order) void __memcg_kmem_commit_charge(struct page *page, struct mem_cgroup *memcg, int order) { - struct page_cgroup *pc; - VM_BUG_ON(mem_cgroup_is_root(memcg)); /* The page allocation failed. Revert */ if (!page) { - memcg_uncharge_kmem(memcg, PAGE_SIZE << order); + memcg_uncharge_kmem(memcg, 1 << order); return; } - /* - * The page is freshly allocated and not visible to any - * outside callers yet. Set up pc non-atomically. - */ - pc = lookup_page_cgroup(page); - pc->mem_cgroup = memcg; - pc->flags = PCG_USED; + page->mem_cgroup = memcg; } void __memcg_kmem_uncharge_pages(struct page *page, int order) { - struct mem_cgroup *memcg = NULL; - struct page_cgroup *pc; - + struct mem_cgroup *memcg = page->mem_cgroup; - pc = lookup_page_cgroup(page); - if (!PageCgroupUsed(pc)) - return; - - memcg = pc->mem_cgroup; - pc->flags = 0; - - /* - * We trust that only if there is a memcg associated with the page, it - * is a valid allocation - */ if (!memcg) return; VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page); - memcg_uncharge_kmem(memcg, PAGE_SIZE << order); + + memcg_uncharge_kmem(memcg, 1 << order); + page->mem_cgroup = NULL; } #else static inline void memcg_unregister_all_caches(struct mem_cgroup *memcg) @@ -3325,21 +3001,15 @@ static inline void memcg_unregister_all_caches(struct mem_cgroup *memcg) */ void mem_cgroup_split_huge_fixup(struct page *head) { - struct page_cgroup *head_pc = lookup_page_cgroup(head); - struct page_cgroup *pc; - struct mem_cgroup *memcg; int i; if (mem_cgroup_disabled()) return; - memcg = head_pc->mem_cgroup; - for (i = 1; i < HPAGE_PMD_NR; i++) { - pc = head_pc + i; - pc->mem_cgroup = memcg; - pc->flags = head_pc->flags; - } - __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], + for (i = 1; i < HPAGE_PMD_NR; i++) + head[i].mem_cgroup = head->mem_cgroup; + + __this_cpu_sub(head->mem_cgroup->stat->count[MEM_CGROUP_STAT_RSS_HUGE], HPAGE_PMD_NR); } #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ @@ -3348,7 +3018,6 @@ void mem_cgroup_split_huge_fixup(struct page *head) * mem_cgroup_move_account - move account of the page * @page: the page * @nr_pages: number of regular pages (>1 for huge pages) - * @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. * @@ -3361,7 +3030,6 @@ void mem_cgroup_split_huge_fixup(struct page *head) */ static int mem_cgroup_move_account(struct page *page, unsigned int nr_pages, - struct page_cgroup *pc, struct mem_cgroup *from, struct mem_cgroup *to) { @@ -3381,7 +3049,7 @@ static int mem_cgroup_move_account(struct page *page, goto out; /* - * Prevent mem_cgroup_migrate() from looking at pc->mem_cgroup + * Prevent mem_cgroup_migrate() from looking at page->mem_cgroup * of its source page while we change it: page migration takes * both pages off the LRU, but page cache replacement doesn't. */ @@ -3389,10 +3057,10 @@ static int mem_cgroup_move_account(struct page *page, goto out; ret = -EINVAL; - if (!PageCgroupUsed(pc) || pc->mem_cgroup != from) + if (page->mem_cgroup != from) goto out_unlock; - move_lock_mem_cgroup(from, &flags); + spin_lock_irqsave(&from->move_lock, flags); if (!PageAnon(page) && page_mapped(page)) { __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], @@ -3409,14 +3077,15 @@ static int mem_cgroup_move_account(struct page *page, } /* - * It is safe to change pc->mem_cgroup here because the page + * It is safe to change page->mem_cgroup here because the page * is referenced, charged, and isolated - we can't race with * uncharging, charging, migration, or LRU putback. */ /* caller should have done css_get */ - pc->mem_cgroup = to; - move_unlock_mem_cgroup(from, &flags); + page->mem_cgroup = to; + spin_unlock_irqrestore(&from->move_lock, flags); + ret = 0; local_irq_disable(); @@ -3431,72 +3100,6 @@ out: return ret; } -/** - * mem_cgroup_move_parent - moves page to the parent group - * @page: the page to move - * @pc: page_cgroup of the page - * @child: page's cgroup - * - * move charges to its parent or the root cgroup if the group has no - * parent (aka use_hierarchy==0). - * Although this might fail (get_page_unless_zero, isolate_lru_page or - * mem_cgroup_move_account fails) the failure is always temporary and - * it signals a race with a page removal/uncharge or migration. In the - * first case the page is on the way out and it will vanish from the LRU - * on the next attempt and the call should be retried later. - * Isolation from the LRU fails only if page has been isolated from - * the LRU since we looked at it and that usually means either global - * reclaim or migration going on. The page will either get back to the - * LRU or vanish. - * Finaly mem_cgroup_move_account fails only if the page got uncharged - * (!PageCgroupUsed) or moved to a different group. The page will - * disappear in the next attempt. - */ -static int mem_cgroup_move_parent(struct page *page, - struct page_cgroup *pc, - struct mem_cgroup *child) -{ - struct mem_cgroup *parent; - unsigned int nr_pages; - unsigned long uninitialized_var(flags); - int ret; - - VM_BUG_ON(mem_cgroup_is_root(child)); - - ret = -EBUSY; - if (!get_page_unless_zero(page)) - goto out; - if (isolate_lru_page(page)) - goto put; - - nr_pages = hpage_nr_pages(page); - - parent = parent_mem_cgroup(child); - /* - * If no parent, move charges to root cgroup. - */ - if (!parent) - parent = root_mem_cgroup; - - if (nr_pages > 1) { - VM_BUG_ON_PAGE(!PageTransHuge(page), page); - flags = compound_lock_irqsave(page); - } - - ret = mem_cgroup_move_account(page, nr_pages, - pc, child, parent); - if (!ret) - __mem_cgroup_cancel_local_charge(child, nr_pages); - - if (nr_pages > 1) - compound_unlock_irqrestore(page, flags); - putback_lru_page(page); -put: - put_page(page); -out: - return ret; -} - #ifdef CONFIG_MEMCG_SWAP static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, bool charge) @@ -3516,7 +3119,7 @@ static void mem_cgroup_swap_statistics(struct mem_cgroup *memcg, * * Returns 0 on success, -EINVAL on failure. * - * The caller must have charged to @to, IOW, called res_counter_charge() about + * The caller must have charged to @to, IOW, called page_counter_charge() about * both res and memsw, and called css_get(). */ static int mem_cgroup_move_swap_account(swp_entry_t entry, @@ -3532,7 +3135,7 @@ static int mem_cgroup_move_swap_account(swp_entry_t entry, mem_cgroup_swap_statistics(to, true); /* * This function is only called from task migration context now. - * It postpones res_counter and refcount handling till the end + * It postpones page_counter and refcount handling till the end * of task migration(mem_cgroup_clear_mc()) for performance * improvement. But we cannot postpone css_get(to) because if * the process that has been moved to @to does swap-in, the @@ -3554,96 +3157,57 @@ static inline int mem_cgroup_move_swap_account(swp_entry_t entry, } #endif -#ifdef CONFIG_DEBUG_VM -static struct page_cgroup *lookup_page_cgroup_used(struct page *page) -{ - struct page_cgroup *pc; - - pc = lookup_page_cgroup(page); - /* - * Can be NULL while feeding pages into the page allocator for - * the first time, i.e. during boot or memory hotplug; - * or when mem_cgroup_disabled(). - */ - if (likely(pc) && PageCgroupUsed(pc)) - return pc; - return NULL; -} - -bool mem_cgroup_bad_page_check(struct page *page) -{ - if (mem_cgroup_disabled()) - return false; - - return lookup_page_cgroup_used(page) != NULL; -} - -void mem_cgroup_print_bad_page(struct page *page) -{ - struct page_cgroup *pc; - - pc = lookup_page_cgroup_used(page); - if (pc) { - pr_alert("pc:%p pc->flags:%lx pc->mem_cgroup:%p\n", - pc, pc->flags, pc->mem_cgroup); - } -} -#endif +static DEFINE_MUTEX(memcg_limit_mutex); static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, - unsigned long long val) + unsigned long limit) { + unsigned long curusage; + unsigned long oldusage; + bool enlarge = false; int retry_count; - int ret = 0; - int children = mem_cgroup_count_children(memcg); - u64 curusage, oldusage; - int enlarge; + int ret; /* * For keeping hierarchical_reclaim simple, how long we should retry * is depends on callers. We set our retry-count to be function * of # of children which we should visit in this loop. */ - retry_count = MEM_CGROUP_RECLAIM_RETRIES * children; + retry_count = MEM_CGROUP_RECLAIM_RETRIES * + mem_cgroup_count_children(memcg); - oldusage = res_counter_read_u64(&memcg->res, RES_USAGE); + oldusage = page_counter_read(&memcg->memory); - enlarge = 0; - while (retry_count) { + do { if (signal_pending(current)) { ret = -EINTR; break; } - /* - * Rather than hide all in some function, I do this in - * open coded manner. You see what this really does. - * We have to guarantee memcg->res.limit <= memcg->memsw.limit. - */ - mutex_lock(&set_limit_mutex); - if (res_counter_read_u64(&memcg->memsw, RES_LIMIT) < val) { + + mutex_lock(&memcg_limit_mutex); + if (limit > memcg->memsw.limit) { + mutex_unlock(&memcg_limit_mutex); ret = -EINVAL; - mutex_unlock(&set_limit_mutex); break; } - - if (res_counter_read_u64(&memcg->res, RES_LIMIT) < val) - enlarge = 1; - - ret = res_counter_set_limit(&memcg->res, val); - mutex_unlock(&set_limit_mutex); + if (limit > memcg->memory.limit) + enlarge = true; + ret = page_counter_limit(&memcg->memory, limit); + mutex_unlock(&memcg_limit_mutex); if (!ret) break; try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, true); - curusage = res_counter_read_u64(&memcg->res, RES_USAGE); + curusage = page_counter_read(&memcg->memory); /* Usage is reduced ? */ if (curusage >= oldusage) retry_count--; else oldusage = curusage; - } + } while (retry_count); + if (!ret && enlarge) memcg_oom_recover(memcg); @@ -3651,52 +3215,53 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg, } static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg, - unsigned long long val) + unsigned long limit) { + unsigned long curusage; + unsigned long oldusage; + bool enlarge = false; int retry_count; - u64 oldusage, curusage; - int children = mem_cgroup_count_children(memcg); - int ret = -EBUSY; - int enlarge = 0; + int ret; /* see mem_cgroup_resize_res_limit */ - retry_count = children * MEM_CGROUP_RECLAIM_RETRIES; - oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); - while (retry_count) { + retry_count = MEM_CGROUP_RECLAIM_RETRIES * + mem_cgroup_count_children(memcg); + + oldusage = page_counter_read(&memcg->memsw); + + do { if (signal_pending(current)) { ret = -EINTR; break; } - /* - * Rather than hide all in some function, I do this in - * open coded manner. You see what this really does. - * We have to guarantee memcg->res.limit <= memcg->memsw.limit. - */ - mutex_lock(&set_limit_mutex); - if (res_counter_read_u64(&memcg->res, RES_LIMIT) > val) { + + mutex_lock(&memcg_limit_mutex); + if (limit < memcg->memory.limit) { + mutex_unlock(&memcg_limit_mutex); ret = -EINVAL; - mutex_unlock(&set_limit_mutex); break; } - if (res_counter_read_u64(&memcg->memsw, RES_LIMIT) < val) - enlarge = 1; - ret = res_counter_set_limit(&memcg->memsw, val); - mutex_unlock(&set_limit_mutex); + if (limit > memcg->memsw.limit) + enlarge = true; + ret = page_counter_limit(&memcg->memsw, limit); + mutex_unlock(&memcg_limit_mutex); if (!ret) break; try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, false); - curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE); + curusage = page_counter_read(&memcg->memsw); /* Usage is reduced ? */ if (curusage >= oldusage) retry_count--; else oldusage = curusage; - } + } while (retry_count); + if (!ret && enlarge) memcg_oom_recover(memcg); + return ret; } @@ -3709,7 +3274,7 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, unsigned long reclaimed; int loop = 0; struct mem_cgroup_tree_per_zone *mctz; - unsigned long long excess; + unsigned long excess; unsigned long nr_scanned; if (order > 0) @@ -3735,35 +3300,17 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, nr_reclaimed += reclaimed; *total_scanned += nr_scanned; spin_lock_irq(&mctz->lock); + __mem_cgroup_remove_exceeded(mz, mctz); /* * If we failed to reclaim anything from this memory cgroup * it is time to move on to the next cgroup */ next_mz = NULL; - if (!reclaimed) { - do { - /* - * Loop until we find yet another one. - * - * By the time we get the soft_limit lock - * again, someone might have aded the - * group back on the RB tree. Iterate to - * make sure we get a different mem. - * mem_cgroup_largest_soft_limit_node returns - * NULL if no other cgroup is present on - * the tree - */ - next_mz = - __mem_cgroup_largest_soft_limit_node(mctz); - if (next_mz == mz) - css_put(&next_mz->memcg->css); - else /* next_mz == NULL or other memcg */ - break; - } while (1); - } - __mem_cgroup_remove_exceeded(mz, mctz); - excess = res_counter_soft_limit_excess(&mz->memcg->res); + if (!reclaimed) + next_mz = __mem_cgroup_largest_soft_limit_node(mctz); + + excess = soft_limit_excess(mz->memcg); /* * One school of thought says that we should not add * back the node to the tree if reclaim returns 0. @@ -3792,107 +3339,6 @@ unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order, return nr_reclaimed; } -/** - * mem_cgroup_force_empty_list - clears LRU of a group - * @memcg: group to clear - * @node: NUMA node - * @zid: zone id - * @lru: lru to to clear - * - * Traverse a specified page_cgroup list and try to drop them all. This doesn't - * reclaim the pages page themselves - pages are moved to the parent (or root) - * group. - */ -static void mem_cgroup_force_empty_list(struct mem_cgroup *memcg, - int node, int zid, enum lru_list lru) -{ - struct lruvec *lruvec; - unsigned long flags; - struct list_head *list; - struct page *busy; - struct zone *zone; - - zone = &NODE_DATA(node)->node_zones[zid]; - lruvec = mem_cgroup_zone_lruvec(zone, memcg); - list = &lruvec->lists[lru]; - - busy = NULL; - do { - struct page_cgroup *pc; - struct page *page; - - spin_lock_irqsave(&zone->lru_lock, flags); - if (list_empty(list)) { - spin_unlock_irqrestore(&zone->lru_lock, flags); - break; - } - page = list_entry(list->prev, struct page, lru); - if (busy == page) { - list_move(&page->lru, list); - busy = NULL; - spin_unlock_irqrestore(&zone->lru_lock, flags); - continue; - } - spin_unlock_irqrestore(&zone->lru_lock, flags); - - pc = lookup_page_cgroup(page); - - if (mem_cgroup_move_parent(page, pc, memcg)) { - /* found lock contention or "pc" is obsolete. */ - busy = page; - } else - busy = NULL; - cond_resched(); - } while (!list_empty(list)); -} - -/* - * make mem_cgroup's charge to be 0 if there is no task by moving - * all the charges and pages to the parent. - * This enables deleting this mem_cgroup. - * - * Caller is responsible for holding css reference on the memcg. - */ -static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg) -{ - int node, zid; - u64 usage; - - do { - /* This is for making all *used* pages to be on LRU. */ - lru_add_drain_all(); - drain_all_stock_sync(memcg); - mem_cgroup_start_move(memcg); - for_each_node_state(node, N_MEMORY) { - for (zid = 0; zid < MAX_NR_ZONES; zid++) { - enum lru_list lru; - for_each_lru(lru) { - mem_cgroup_force_empty_list(memcg, - node, zid, lru); - } - } - } - mem_cgroup_end_move(memcg); - memcg_oom_recover(memcg); - cond_resched(); - - /* - * Kernel memory may not necessarily be trackable to a specific - * process. So they are not migrated, and therefore we can't - * expect their value to drop to 0 here. - * Having res filled up with kmem only is enough. - * - * This is a safety check because mem_cgroup_force_empty_list - * could have raced with mem_cgroup_replace_page_cache callers - * so the lru seemed empty but the page could have been added - * right after the check. RES_USAGE should be safe as we always - * charge before adding to the LRU. - */ - usage = res_counter_read_u64(&memcg->res, RES_USAGE) - - res_counter_read_u64(&memcg->kmem, RES_USAGE); - } while (usage > 0); -} - /* * Test whether @memcg has children, dead or alive. Note that this * function doesn't care whether @memcg has use_hierarchy enabled and @@ -3930,7 +3376,7 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg) /* we call try-to-free pages for make this cgroup empty */ lru_add_drain_all(); /* try to free all pages in this cgroup */ - while (nr_retries && res_counter_read_u64(&memcg->res, RES_USAGE) > 0) { + while (nr_retries && page_counter_read(&memcg->memory)) { int progress; if (signal_pending(current)) @@ -4001,8 +3447,8 @@ out: return retval; } -static unsigned long mem_cgroup_recursive_stat(struct mem_cgroup *memcg, - enum mem_cgroup_stat_index idx) +static unsigned long tree_stat(struct mem_cgroup *memcg, + enum mem_cgroup_stat_index idx) { struct mem_cgroup *iter; long val = 0; @@ -4020,55 +3466,71 @@ static inline u64 mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) { u64 val; - if (!mem_cgroup_is_root(memcg)) { + if (mem_cgroup_is_root(memcg)) { + val = tree_stat(memcg, MEM_CGROUP_STAT_CACHE); + val += tree_stat(memcg, MEM_CGROUP_STAT_RSS); + if (swap) + val += tree_stat(memcg, MEM_CGROUP_STAT_SWAP); + } else { if (!swap) - return res_counter_read_u64(&memcg->res, RES_USAGE); + val = page_counter_read(&memcg->memory); else - return res_counter_read_u64(&memcg->memsw, RES_USAGE); + val = page_counter_read(&memcg->memsw); } - - /* - * Transparent hugepages are still accounted for in MEM_CGROUP_STAT_RSS - * as well as in MEM_CGROUP_STAT_RSS_HUGE. - */ - val = mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_CACHE); - val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_RSS); - - if (swap) - val += mem_cgroup_recursive_stat(memcg, MEM_CGROUP_STAT_SWAP); - return val << PAGE_SHIFT; } +enum { + RES_USAGE, + RES_LIMIT, + RES_MAX_USAGE, + RES_FAILCNT, + RES_SOFT_LIMIT, +}; static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css, struct cftype *cft) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - enum res_type type = MEMFILE_TYPE(cft->private); - int name = MEMFILE_ATTR(cft->private); + struct page_counter *counter; - switch (type) { + switch (MEMFILE_TYPE(cft->private)) { case _MEM: - if (name == RES_USAGE) - return mem_cgroup_usage(memcg, false); - return res_counter_read_u64(&memcg->res, name); + counter = &memcg->memory; + break; case _MEMSWAP: - if (name == RES_USAGE) - return mem_cgroup_usage(memcg, true); - return res_counter_read_u64(&memcg->memsw, name); + counter = &memcg->memsw; + break; case _KMEM: - return res_counter_read_u64(&memcg->kmem, name); + counter = &memcg->kmem; break; default: BUG(); } + + switch (MEMFILE_ATTR(cft->private)) { + case RES_USAGE: + if (counter == &memcg->memory) + return mem_cgroup_usage(memcg, false); + if (counter == &memcg->memsw) + return mem_cgroup_usage(memcg, true); + return (u64)page_counter_read(counter) * PAGE_SIZE; + case RES_LIMIT: + return (u64)counter->limit * PAGE_SIZE; + case RES_MAX_USAGE: + return (u64)counter->watermark * PAGE_SIZE; + case RES_FAILCNT: + return counter->failcnt; + case RES_SOFT_LIMIT: + return (u64)memcg->soft_limit * PAGE_SIZE; + default: + BUG(); + } } #ifdef CONFIG_MEMCG_KMEM -/* should be called with activate_kmem_mutex held */ -static int __memcg_activate_kmem(struct mem_cgroup *memcg, - unsigned long long limit) +static int memcg_activate_kmem(struct mem_cgroup *memcg, + unsigned long nr_pages) { int err = 0; int memcg_id; @@ -4115,7 +3577,7 @@ static int __memcg_activate_kmem(struct mem_cgroup *memcg, * We couldn't have accounted to this cgroup, because it hasn't got the * active bit set yet, so this should succeed. */ - err = res_counter_set_limit(&memcg->kmem, limit); + err = page_counter_limit(&memcg->kmem, nr_pages); VM_BUG_ON(err); static_key_slow_inc(&memcg_kmem_enabled_key); @@ -4130,26 +3592,17 @@ out: return err; } -static int memcg_activate_kmem(struct mem_cgroup *memcg, - unsigned long long limit) -{ - int ret; - - mutex_lock(&activate_kmem_mutex); - ret = __memcg_activate_kmem(memcg, limit); - mutex_unlock(&activate_kmem_mutex); - return ret; -} - static int memcg_update_kmem_limit(struct mem_cgroup *memcg, - unsigned long long val) + unsigned long limit) { int ret; + mutex_lock(&memcg_limit_mutex); if (!memcg_kmem_is_active(memcg)) - ret = memcg_activate_kmem(memcg, val); + ret = memcg_activate_kmem(memcg, limit); else - ret = res_counter_set_limit(&memcg->kmem, val); + ret = page_counter_limit(&memcg->kmem, limit); + mutex_unlock(&memcg_limit_mutex); return ret; } @@ -4161,19 +3614,19 @@ static int memcg_propagate_kmem(struct mem_cgroup *memcg) if (!parent) return 0; - mutex_lock(&activate_kmem_mutex); + mutex_lock(&memcg_limit_mutex); /* * If the parent cgroup is not kmem-active now, it cannot be activated * after this point, because it has at least one child already. */ if (memcg_kmem_is_active(parent)) - ret = __memcg_activate_kmem(memcg, RES_COUNTER_MAX); - mutex_unlock(&activate_kmem_mutex); + ret = memcg_activate_kmem(memcg, PAGE_COUNTER_MAX); + mutex_unlock(&memcg_limit_mutex); return ret; } #else static int memcg_update_kmem_limit(struct mem_cgroup *memcg, - unsigned long long val) + unsigned long limit) { return -EINVAL; } @@ -4187,110 +3640,69 @@ static ssize_t mem_cgroup_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); - enum res_type type; - int name; - unsigned long long val; + unsigned long nr_pages; int ret; buf = strstrip(buf); - type = MEMFILE_TYPE(of_cft(of)->private); - name = MEMFILE_ATTR(of_cft(of)->private); + ret = page_counter_memparse(buf, &nr_pages); + if (ret) + return ret; - switch (name) { + switch (MEMFILE_ATTR(of_cft(of)->private)) { case RES_LIMIT: if (mem_cgroup_is_root(memcg)) { /* Can't set limit on root */ ret = -EINVAL; break; } - /* This function does all necessary parse...reuse it */ - ret = res_counter_memparse_write_strategy(buf, &val); - if (ret) + switch (MEMFILE_TYPE(of_cft(of)->private)) { + case _MEM: + ret = mem_cgroup_resize_limit(memcg, nr_pages); break; - if (type == _MEM) - ret = mem_cgroup_resize_limit(memcg, val); - else if (type == _MEMSWAP) - ret = mem_cgroup_resize_memsw_limit(memcg, val); - else if (type == _KMEM) - ret = memcg_update_kmem_limit(memcg, val); - else - return -EINVAL; - break; - case RES_SOFT_LIMIT: - ret = res_counter_memparse_write_strategy(buf, &val); - if (ret) + case _MEMSWAP: + ret = mem_cgroup_resize_memsw_limit(memcg, nr_pages); break; - /* - * For memsw, soft limits are hard to implement in terms - * of semantics, for now, we support soft limits for - * control without swap - */ - if (type == _MEM) - ret = res_counter_set_soft_limit(&memcg->res, val); - else - ret = -EINVAL; + case _KMEM: + ret = memcg_update_kmem_limit(memcg, nr_pages); + break; + } break; - default: - ret = -EINVAL; /* should be BUG() ? */ + case RES_SOFT_LIMIT: + memcg->soft_limit = nr_pages; + ret = 0; break; } return ret ?: nbytes; } -static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg, - unsigned long long *mem_limit, unsigned long long *memsw_limit) -{ - unsigned long long min_limit, min_memsw_limit, tmp; - - min_limit = res_counter_read_u64(&memcg->res, RES_LIMIT); - min_memsw_limit = res_counter_read_u64(&memcg->memsw, RES_LIMIT); - if (!memcg->use_hierarchy) - goto out; - - while (memcg->css.parent) { - memcg = mem_cgroup_from_css(memcg->css.parent); - if (!memcg->use_hierarchy) - break; - tmp = res_counter_read_u64(&memcg->res, RES_LIMIT); - min_limit = min(min_limit, tmp); - tmp = res_counter_read_u64(&memcg->memsw, RES_LIMIT); - min_memsw_limit = min(min_memsw_limit, tmp); - } -out: - *mem_limit = min_limit; - *memsw_limit = min_memsw_limit; -} - static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); - int name; - enum res_type type; + struct page_counter *counter; - type = MEMFILE_TYPE(of_cft(of)->private); - name = MEMFILE_ATTR(of_cft(of)->private); + switch (MEMFILE_TYPE(of_cft(of)->private)) { + case _MEM: + counter = &memcg->memory; + break; + case _MEMSWAP: + counter = &memcg->memsw; + break; + case _KMEM: + counter = &memcg->kmem; + break; + default: + BUG(); + } - switch (name) { + switch (MEMFILE_ATTR(of_cft(of)->private)) { case RES_MAX_USAGE: - if (type == _MEM) - res_counter_reset_max(&memcg->res); - else if (type == _MEMSWAP) - res_counter_reset_max(&memcg->memsw); - else if (type == _KMEM) - res_counter_reset_max(&memcg->kmem); - else - return -EINVAL; + page_counter_reset_watermark(counter); break; case RES_FAILCNT: - if (type == _MEM) - res_counter_reset_failcnt(&memcg->res); - else if (type == _MEMSWAP) - res_counter_reset_failcnt(&memcg->memsw); - else if (type == _KMEM) - res_counter_reset_failcnt(&memcg->kmem); - else - return -EINVAL; + counter->failcnt = 0; break; + default: + BUG(); } return nbytes; @@ -4387,6 +3799,7 @@ static inline void mem_cgroup_lru_names_not_uptodate(void) static int memcg_stat_show(struct seq_file *m, void *v) { struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); + unsigned long memory, memsw; struct mem_cgroup *mi; unsigned int i; @@ -4406,14 +3819,16 @@ static int memcg_stat_show(struct seq_file *m, void *v) mem_cgroup_nr_lru_pages(memcg, BIT(i)) * PAGE_SIZE); /* Hierarchical information */ - { - unsigned long long limit, memsw_limit; - memcg_get_hierarchical_limit(memcg, &limit, &memsw_limit); - seq_printf(m, "hierarchical_memory_limit %llu\n", limit); - if (do_swap_account) - seq_printf(m, "hierarchical_memsw_limit %llu\n", - memsw_limit); + memory = memsw = PAGE_COUNTER_MAX; + for (mi = memcg; mi; mi = parent_mem_cgroup(mi)) { + memory = min(memory, mi->memory.limit); + memsw = min(memsw, mi->memsw.limit); } + seq_printf(m, "hierarchical_memory_limit %llu\n", + (u64)memory * PAGE_SIZE); + if (do_swap_account) + seq_printf(m, "hierarchical_memsw_limit %llu\n", + (u64)memsw * PAGE_SIZE); for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) { long long val = 0; @@ -4497,7 +3912,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap) { struct mem_cgroup_threshold_ary *t; - u64 usage; + unsigned long usage; int i; rcu_read_lock(); @@ -4596,10 +4011,11 @@ static int __mem_cgroup_usage_register_event(struct mem_cgroup *memcg, { struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; - u64 threshold, usage; + unsigned long threshold; + unsigned long usage; int i, size, ret; - ret = res_counter_memparse_write_strategy(args, &threshold); + ret = page_counter_memparse(args, &threshold); if (ret) return ret; @@ -4689,7 +4105,7 @@ static void __mem_cgroup_usage_unregister_event(struct mem_cgroup *memcg, { struct mem_cgroup_thresholds *thresholds; struct mem_cgroup_threshold_ary *new; - u64 usage; + unsigned long usage; int i, j, size; mutex_lock(&memcg->thresholds_lock); @@ -4855,40 +4271,6 @@ static void memcg_destroy_kmem(struct mem_cgroup *memcg) { mem_cgroup_sockets_destroy(memcg); } - -static void kmem_cgroup_css_offline(struct mem_cgroup *memcg) -{ - if (!memcg_kmem_is_active(memcg)) - return; - - /* - * kmem charges can outlive the cgroup. In the case of slab - * pages, for instance, a page contain objects from various - * processes. As we prevent from taking a reference for every - * such allocation we have to be careful when doing uncharge - * (see memcg_uncharge_kmem) and here during offlining. - * - * The idea is that that only the _last_ uncharge which sees - * the dead memcg will drop the last reference. An additional - * reference is taken here before the group is marked dead - * which is then paired with css_put during uncharge resp. here. - * - * Although this might sound strange as this path is called from - * css_offline() when the referencemight have dropped down to 0 and - * shouldn't be incremented anymore (css_tryget_online() would - * fail) we do not have other options because of the kmem - * allocations lifetime. - */ - css_get(&memcg->css); - - memcg_kmem_mark_dead(memcg); - - if (res_counter_read_u64(&memcg->kmem, RES_USAGE) != 0) - return; - - if (memcg_kmem_test_and_clear_dead(memcg)) - css_put(&memcg->css); -} #else static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss) { @@ -4898,10 +4280,6 @@ static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss) static void memcg_destroy_kmem(struct mem_cgroup *memcg) { } - -static void kmem_cgroup_css_offline(struct mem_cgroup *memcg) -{ -} #endif /* @@ -5228,7 +4606,10 @@ static struct cftype mem_cgroup_files[] = { #ifdef CONFIG_SLABINFO { .name = "kmem.slabinfo", - .seq_show = mem_cgroup_slabinfo_read, + .seq_start = slab_start, + .seq_next = slab_next, + .seq_stop = slab_stop, + .seq_show = memcg_slab_show, }, #endif #endif @@ -5363,9 +4744,9 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg) */ struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { - if (!memcg->res.parent) + if (!memcg->memory.parent) return NULL; - return mem_cgroup_from_res_counter(memcg->res.parent, res); + return mem_cgroup_from_counter(memcg->memory.parent, memory); } EXPORT_SYMBOL(parent_mem_cgroup); @@ -5410,9 +4791,9 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) /* root ? */ if (parent_css == NULL) { root_mem_cgroup = memcg; - res_counter_init(&memcg->res, NULL); - res_counter_init(&memcg->memsw, NULL); - res_counter_init(&memcg->kmem, NULL); + page_counter_init(&memcg->memory, NULL); + page_counter_init(&memcg->memsw, NULL); + page_counter_init(&memcg->kmem, NULL); } memcg->last_scanned_node = MAX_NUMNODES; @@ -5451,18 +4832,18 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css) memcg->swappiness = mem_cgroup_swappiness(parent); if (parent->use_hierarchy) { - res_counter_init(&memcg->res, &parent->res); - res_counter_init(&memcg->memsw, &parent->memsw); - res_counter_init(&memcg->kmem, &parent->kmem); + page_counter_init(&memcg->memory, &parent->memory); + page_counter_init(&memcg->memsw, &parent->memsw); + page_counter_init(&memcg->kmem, &parent->kmem); /* * No need to take a reference to the parent because cgroup * core guarantees its existence. */ } else { - res_counter_init(&memcg->res, NULL); - res_counter_init(&memcg->memsw, NULL); - res_counter_init(&memcg->kmem, NULL); + page_counter_init(&memcg->memory, NULL); + page_counter_init(&memcg->memsw, NULL); + page_counter_init(&memcg->kmem, NULL); /* * Deeper hierachy with use_hierarchy == false doesn't make * much sense so let cgroup subsystem know about this @@ -5487,29 +4868,10 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css) return 0; } -/* - * Announce all parents that a group from their hierarchy is gone. - */ -static void mem_cgroup_invalidate_reclaim_iterators(struct mem_cgroup *memcg) -{ - struct mem_cgroup *parent = memcg; - - while ((parent = parent_mem_cgroup(parent))) - mem_cgroup_iter_invalidate(parent); - - /* - * if the root memcg is not hierarchical we have to check it - * explicitely. - */ - if (!root_mem_cgroup->use_hierarchy) - mem_cgroup_iter_invalidate(root_mem_cgroup); -} - static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup_event *event, *tmp; - struct cgroup_subsys_state *iter; /* * Unregister events and notify userspace. @@ -5523,17 +4885,6 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) } spin_unlock(&memcg->event_list_lock); - kmem_cgroup_css_offline(memcg); - - mem_cgroup_invalidate_reclaim_iterators(memcg); - - /* - * This requires that offlining is serialized. Right now that is - * guaranteed because css_killed_work_fn() holds the cgroup_mutex. - */ - css_for_each_descendant_post(iter, css) - mem_cgroup_reparent_charges(mem_cgroup_from_css(iter)); - memcg_unregister_all_caches(memcg); vmpressure_cleanup(&memcg->vmpressure); } @@ -5541,42 +4892,6 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) static void mem_cgroup_css_free(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - /* - * XXX: css_offline() would be where we should reparent all - * memory to prepare the cgroup for destruction. However, - * memcg does not do css_tryget_online() and res_counter charging - * under the same RCU lock region, which means that charging - * could race with offlining. Offlining only happens to - * cgroups with no tasks in them but charges can show up - * without any tasks from the swapin path when the target - * memcg is looked up from the swapout record and not from the - * current task as it usually is. A race like this can leak - * charges and put pages with stale cgroup pointers into - * circulation: - * - * #0 #1 - * lookup_swap_cgroup_id() - * rcu_read_lock() - * mem_cgroup_lookup() - * css_tryget_online() - * rcu_read_unlock() - * disable css_tryget_online() - * call_rcu() - * offline_css() - * reparent_charges() - * res_counter_charge() - * css_put() - * css_free() - * pc->mem_cgroup = dead memcg - * add page to lru - * - * The bulk of the charges are still moved in offline_css() to - * avoid pinning a lot of pages in case a long-term reference - * like a swapout record is deferring the css_free() to long - * after offlining. But this makes sure we catch any charges - * made after offlining: - */ - mem_cgroup_reparent_charges(memcg); memcg_destroy_kmem(memcg); __mem_cgroup_free(memcg); @@ -5599,10 +4914,10 @@ static void mem_cgroup_css_reset(struct cgroup_subsys_state *css) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - mem_cgroup_resize_limit(memcg, ULLONG_MAX); - mem_cgroup_resize_memsw_limit(memcg, ULLONG_MAX); - memcg_update_kmem_limit(memcg, ULLONG_MAX); - res_counter_set_soft_limit(&memcg->res, ULLONG_MAX); + mem_cgroup_resize_limit(memcg, PAGE_COUNTER_MAX); + mem_cgroup_resize_memsw_limit(memcg, PAGE_COUNTER_MAX); + memcg_update_kmem_limit(memcg, PAGE_COUNTER_MAX); + memcg->soft_limit = 0; } #ifdef CONFIG_MMU @@ -5758,7 +5073,6 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, unsigned long addr, pte_t ptent, union mc_target *target) { struct page *page = NULL; - struct page_cgroup *pc; enum mc_target_type ret = MC_TARGET_NONE; swp_entry_t ent = { .val = 0 }; @@ -5772,13 +5086,12 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, if (!page && !ent.val) return ret; if (page) { - pc = lookup_page_cgroup(page); /* * Do only loose check w/o serialization. - * mem_cgroup_move_account() checks the pc is valid or + * mem_cgroup_move_account() checks the page is valid or * not under LRU exclusion. */ - if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { + if (page->mem_cgroup == mc.from) { ret = MC_TARGET_PAGE; if (target) target->page = page; @@ -5806,15 +5119,13 @@ static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma, unsigned long addr, pmd_t pmd, union mc_target *target) { struct page *page = NULL; - struct page_cgroup *pc; enum mc_target_type ret = MC_TARGET_NONE; page = pmd_page(pmd); VM_BUG_ON_PAGE(!page || !PageHead(page), page); if (!move_anon()) return ret; - pc = lookup_page_cgroup(page); - if (PageCgroupUsed(pc) && pc->mem_cgroup == mc.from) { + if (page->mem_cgroup == mc.from) { ret = MC_TARGET_PAGE; if (target) { get_page(page); @@ -5897,7 +5208,6 @@ static void __mem_cgroup_clear_mc(void) { struct mem_cgroup *from = mc.from; struct mem_cgroup *to = mc.to; - int i; /* we must uncharge all the leftover precharges from mc.to */ if (mc.precharge) { @@ -5916,19 +5226,17 @@ static void __mem_cgroup_clear_mc(void) if (mc.moved_swap) { /* uncharge swap account from the old cgroup */ if (!mem_cgroup_is_root(mc.from)) - res_counter_uncharge(&mc.from->memsw, - PAGE_SIZE * mc.moved_swap); - - for (i = 0; i < mc.moved_swap; i++) - css_put(&mc.from->css); + page_counter_uncharge(&mc.from->memsw, mc.moved_swap); /* - * we charged both to->res and to->memsw, so we should - * uncharge to->res. + * we charged both to->memory and to->memsw, so we + * should uncharge to->memory. */ if (!mem_cgroup_is_root(mc.to)) - res_counter_uncharge(&mc.to->res, - PAGE_SIZE * mc.moved_swap); + page_counter_uncharge(&mc.to->memory, mc.moved_swap); + + css_put_many(&mc.from->css, mc.moved_swap); + /* we've already done css_get(mc.to) */ mc.moved_swap = 0; } @@ -5939,8 +5247,6 @@ static void __mem_cgroup_clear_mc(void) static void mem_cgroup_clear_mc(void) { - struct mem_cgroup *from = mc.from; - /* * we must clear moving_task before waking up waiters at the end of * task migration. @@ -5951,7 +5257,6 @@ static void mem_cgroup_clear_mc(void) mc.from = NULL; mc.to = NULL; spin_unlock(&mc.lock); - mem_cgroup_end_move(from); } static int mem_cgroup_can_attach(struct cgroup_subsys_state *css, @@ -5984,7 +5289,7 @@ static int mem_cgroup_can_attach(struct cgroup_subsys_state *css, VM_BUG_ON(mc.precharge); VM_BUG_ON(mc.moved_charge); VM_BUG_ON(mc.moved_swap); - mem_cgroup_start_move(from); + spin_lock(&mc.lock); mc.from = from; mc.to = memcg; @@ -6004,7 +5309,8 @@ static int mem_cgroup_can_attach(struct cgroup_subsys_state *css, static void mem_cgroup_cancel_attach(struct cgroup_subsys_state *css, struct cgroup_taskset *tset) { - mem_cgroup_clear_mc(); + if (mc.to) + mem_cgroup_clear_mc(); } static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, @@ -6018,7 +5324,6 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, enum mc_target_type target_type; union mc_target target; struct page *page; - struct page_cgroup *pc; /* * We don't take compound_lock() here but no race with splitting thp @@ -6039,9 +5344,8 @@ static int mem_cgroup_move_charge_pte_range(pmd_t *pmd, if (target_type == MC_TARGET_PAGE) { page = target.page; if (!isolate_lru_page(page)) { - pc = lookup_page_cgroup(page); if (!mem_cgroup_move_account(page, HPAGE_PMD_NR, - pc, mc.from, mc.to)) { + mc.from, mc.to)) { mc.precharge -= HPAGE_PMD_NR; mc.moved_charge += HPAGE_PMD_NR; } @@ -6069,9 +5373,7 @@ retry: page = target.page; if (isolate_lru_page(page)) goto put; - pc = lookup_page_cgroup(page); - if (!mem_cgroup_move_account(page, 1, pc, - mc.from, mc.to)) { + if (!mem_cgroup_move_account(page, 1, mc.from, mc.to)) { mc.precharge--; /* we uncharge from mc.from later. */ mc.moved_charge++; @@ -6115,6 +5417,13 @@ static void mem_cgroup_move_charge(struct mm_struct *mm) struct vm_area_struct *vma; lru_add_drain_all(); + /* + * Signal mem_cgroup_begin_page_stat() to take the memcg's + * move_lock while we're moving its pages to another memcg. + * Then wait for already started RCU-only updates to finish. + */ + atomic_inc(&mc.from->moving_account); + synchronize_rcu(); retry: if (unlikely(!down_read_trylock(&mm->mmap_sem))) { /* @@ -6147,6 +5456,7 @@ retry: break; } up_read(&mm->mmap_sem); + atomic_dec(&mc.from->moving_account); } static void mem_cgroup_move_task(struct cgroup_subsys_state *css, @@ -6250,7 +5560,7 @@ static void __init enable_swap_cgroup(void) */ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) { - struct page_cgroup *pc; + struct mem_cgroup *memcg; unsigned short oldid; VM_BUG_ON_PAGE(PageLRU(page), page); @@ -6259,20 +5569,26 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) if (!do_swap_account) return; - pc = lookup_page_cgroup(page); + memcg = page->mem_cgroup; /* Readahead page, never charged */ - if (!PageCgroupUsed(pc)) + if (!memcg) return; - VM_BUG_ON_PAGE(!(pc->flags & PCG_MEMSW), page); - - oldid = swap_cgroup_record(entry, mem_cgroup_id(pc->mem_cgroup)); + oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg)); VM_BUG_ON_PAGE(oldid, page); + mem_cgroup_swap_statistics(memcg, true); + + page->mem_cgroup = NULL; - pc->flags &= ~PCG_MEMSW; - css_get(&pc->mem_cgroup->css); - mem_cgroup_swap_statistics(pc->mem_cgroup, true); + if (!mem_cgroup_is_root(memcg)) + page_counter_uncharge(&memcg->memory, 1); + + /* XXX: caller holds IRQ-safe mapping->tree_lock */ + VM_BUG_ON(!irqs_disabled()); + + mem_cgroup_charge_statistics(memcg, page, -1); + memcg_check_events(memcg, page); } /** @@ -6294,7 +5610,7 @@ void mem_cgroup_uncharge_swap(swp_entry_t entry) memcg = mem_cgroup_lookup(id); if (memcg) { if (!mem_cgroup_is_root(memcg)) - res_counter_uncharge(&memcg->memsw, PAGE_SIZE); + page_counter_uncharge(&memcg->memsw, 1); mem_cgroup_swap_statistics(memcg, false); css_put(&memcg->css); } @@ -6330,7 +5646,6 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, goto out; if (PageSwapCache(page)) { - struct page_cgroup *pc = lookup_page_cgroup(page); /* * Every swap fault against a single page tries to charge the * page, bail as early as possible. shmem_unuse() encounters @@ -6338,7 +5653,7 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm, * the page lock, which serializes swap cache removal, which * in turn serializes uncharging. */ - if (PageCgroupUsed(pc)) + if (page->mem_cgroup) goto out; } @@ -6452,19 +5767,16 @@ void mem_cgroup_cancel_charge(struct page *page, struct mem_cgroup *memcg) } static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, - unsigned long nr_mem, unsigned long nr_memsw, unsigned long nr_anon, unsigned long nr_file, unsigned long nr_huge, struct page *dummy_page) { + unsigned long nr_pages = nr_anon + nr_file; unsigned long flags; if (!mem_cgroup_is_root(memcg)) { - if (nr_mem) - res_counter_uncharge(&memcg->res, - nr_mem * PAGE_SIZE); - if (nr_memsw) - res_counter_uncharge(&memcg->memsw, - nr_memsw * PAGE_SIZE); + page_counter_uncharge(&memcg->memory, nr_pages); + if (do_swap_account) + page_counter_uncharge(&memcg->memsw, nr_pages); memcg_oom_recover(memcg); } @@ -6473,27 +5785,27 @@ static void uncharge_batch(struct mem_cgroup *memcg, unsigned long pgpgout, __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge); __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout); - __this_cpu_add(memcg->stat->nr_page_events, nr_anon + nr_file); + __this_cpu_add(memcg->stat->nr_page_events, nr_pages); memcg_check_events(memcg, dummy_page); local_irq_restore(flags); + + if (!mem_cgroup_is_root(memcg)) + css_put_many(&memcg->css, nr_pages); } static void uncharge_list(struct list_head *page_list) { struct mem_cgroup *memcg = NULL; - unsigned long nr_memsw = 0; unsigned long nr_anon = 0; unsigned long nr_file = 0; unsigned long nr_huge = 0; unsigned long pgpgout = 0; - unsigned long nr_mem = 0; struct list_head *next; struct page *page; next = page_list->next; do { unsigned int nr_pages = 1; - struct page_cgroup *pc; page = list_entry(next, struct page, lru); next = page->lru.next; @@ -6501,24 +5813,22 @@ static void uncharge_list(struct list_head *page_list) VM_BUG_ON_PAGE(PageLRU(page), page); VM_BUG_ON_PAGE(page_count(page), page); - pc = lookup_page_cgroup(page); - if (!PageCgroupUsed(pc)) + if (!page->mem_cgroup) continue; /* * Nobody should be changing or seriously looking at - * pc->mem_cgroup and pc->flags at this point, we have - * fully exclusive access to the page. + * page->mem_cgroup at this point, we have fully + * exclusive access to the page. */ - if (memcg != pc->mem_cgroup) { + if (memcg != page->mem_cgroup) { if (memcg) { - uncharge_batch(memcg, pgpgout, nr_mem, nr_memsw, - nr_anon, nr_file, nr_huge, page); - pgpgout = nr_mem = nr_memsw = 0; - nr_anon = nr_file = nr_huge = 0; + uncharge_batch(memcg, pgpgout, nr_anon, nr_file, + nr_huge, page); + pgpgout = nr_anon = nr_file = nr_huge = 0; } - memcg = pc->mem_cgroup; + memcg = page->mem_cgroup; } if (PageTransHuge(page)) { @@ -6532,18 +5842,14 @@ static void uncharge_list(struct list_head *page_list) else nr_file += nr_pages; - if (pc->flags & PCG_MEM) - nr_mem += nr_pages; - if (pc->flags & PCG_MEMSW) - nr_memsw += nr_pages; - pc->flags = 0; + page->mem_cgroup = NULL; pgpgout++; } while (next != page_list); if (memcg) - uncharge_batch(memcg, pgpgout, nr_mem, nr_memsw, - nr_anon, nr_file, nr_huge, page); + uncharge_batch(memcg, pgpgout, nr_anon, nr_file, + nr_huge, page); } /** @@ -6555,14 +5861,11 @@ static void uncharge_list(struct list_head *page_list) */ void mem_cgroup_uncharge(struct page *page) { - struct page_cgroup *pc; - if (mem_cgroup_disabled()) return; /* Don't touch page->lru of any random page, pre-check: */ - pc = lookup_page_cgroup(page); - if (!PageCgroupUsed(pc)) + if (!page->mem_cgroup) return; INIT_LIST_HEAD(&page->lru); @@ -6598,7 +5901,7 @@ void mem_cgroup_uncharge_list(struct list_head *page_list) void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, bool lrucare) { - struct page_cgroup *pc; + struct mem_cgroup *memcg; int isolated; VM_BUG_ON_PAGE(!PageLocked(oldpage), oldpage); @@ -6613,27 +5916,28 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, return; /* Page cache replacement: new page already charged? */ - pc = lookup_page_cgroup(newpage); - if (PageCgroupUsed(pc)) + if (newpage->mem_cgroup) return; - /* Re-entrant migration: old page already uncharged? */ - pc = lookup_page_cgroup(oldpage); - if (!PageCgroupUsed(pc)) + /* + * Swapcache readahead pages can get migrated before being + * charged, and migration from compaction can happen to an + * uncharged page when the PFN walker finds a page that + * reclaim just put back on the LRU but has not released yet. + */ + memcg = oldpage->mem_cgroup; + if (!memcg) return; - VM_BUG_ON_PAGE(!(pc->flags & PCG_MEM), oldpage); - VM_BUG_ON_PAGE(do_swap_account && !(pc->flags & PCG_MEMSW), oldpage); - if (lrucare) lock_page_lru(oldpage, &isolated); - pc->flags = 0; + oldpage->mem_cgroup = NULL; if (lrucare) unlock_page_lru(oldpage, isolated); - commit_charge(newpage, pc->mem_cgroup, lrucare); + commit_charge(newpage, memcg, lrucare); } /* |