#include <linux/memcontrol.h>
#include <linux/cgroup.h>
#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/page-flags.h>
+#include <linux/backing-dev.h>
+#include <linux/bit_spinlock.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+#include <linux/swap.h>
+#include <linux/spinlock.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <linux/vmalloc.h>
+
+#include <asm/uaccess.h>
struct cgroup_subsys mem_cgroup_subsys;
+static const int MEM_CGROUP_RECLAIM_RETRIES = 5;
+static struct kmem_cache *page_cgroup_cache;
+
+/*
+ * Statistics for memory cgroup.
+ */
+enum mem_cgroup_stat_index {
+ /*
+ * For MEM_CONTAINER_TYPE_ALL, usage = pagecache + rss.
+ */
+ MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */
+ MEM_CGROUP_STAT_RSS, /* # of pages charged as rss */
+
+ MEM_CGROUP_STAT_NSTATS,
+};
+
+struct mem_cgroup_stat_cpu {
+ s64 count[MEM_CGROUP_STAT_NSTATS];
+} ____cacheline_aligned_in_smp;
+
+struct mem_cgroup_stat {
+ struct mem_cgroup_stat_cpu cpustat[NR_CPUS];
+};
+
+/*
+ * For accounting under irq disable, no need for increment preempt count.
+ */
+static void __mem_cgroup_stat_add_safe(struct mem_cgroup_stat *stat,
+ enum mem_cgroup_stat_index idx, int val)
+{
+ int cpu = smp_processor_id();
+ stat->cpustat[cpu].count[idx] += val;
+}
+
+static s64 mem_cgroup_read_stat(struct mem_cgroup_stat *stat,
+ enum mem_cgroup_stat_index idx)
+{
+ int cpu;
+ s64 ret = 0;
+ for_each_possible_cpu(cpu)
+ ret += stat->cpustat[cpu].count[idx];
+ return ret;
+}
+
+/*
+ * per-zone information in memory controller.
+ */
+
+enum mem_cgroup_zstat_index {
+ MEM_CGROUP_ZSTAT_ACTIVE,
+ MEM_CGROUP_ZSTAT_INACTIVE,
+
+ NR_MEM_CGROUP_ZSTAT,
+};
+
+struct mem_cgroup_per_zone {
+ /*
+ * spin_lock to protect the per cgroup LRU
+ */
+ spinlock_t lru_lock;
+ struct list_head active_list;
+ struct list_head inactive_list;
+ unsigned long count[NR_MEM_CGROUP_ZSTAT];
+};
+/* Macro for accessing counter */
+#define MEM_CGROUP_ZSTAT(mz, idx) ((mz)->count[(idx)])
+
+struct mem_cgroup_per_node {
+ struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
+};
+
+struct mem_cgroup_lru_info {
+ struct mem_cgroup_per_node *nodeinfo[MAX_NUMNODES];
+};
/*
* The memory controller data structure. The memory controller controls both
* to help the administrator determine what knobs to tune.
*
* TODO: Add a water mark for the memory controller. Reclaim will begin when
- * we hit the water mark.
+ * we hit the water mark. May be even add a low water mark, such that
+ * no reclaim occurs from a cgroup at it's low water mark, this is
+ * a feature that will be implemented much later in the future.
*/
struct mem_cgroup {
struct cgroup_subsys_state css;
/*
* Per cgroup active and inactive list, similar to the
* per zone LRU lists.
- * TODO: Consider making these lists per zone
*/
- struct list_head active_list;
- struct list_head inactive_list;
+ struct mem_cgroup_lru_info info;
+
+ int prev_priority; /* for recording reclaim priority */
+ /*
+ * statistics.
+ */
+ struct mem_cgroup_stat stat;
};
+static struct mem_cgroup init_mem_cgroup;
+
+/*
+ * We use the lower bit of the page->page_cgroup pointer as a bit spin
+ * lock. We need to ensure that page->page_cgroup is at least two
+ * byte aligned (based on comments from Nick Piggin). But since
+ * bit_spin_lock doesn't actually set that lock bit in a non-debug
+ * uniprocessor kernel, we should avoid setting it here too.
+ */
+#define PAGE_CGROUP_LOCK_BIT 0x0
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
+#define PAGE_CGROUP_LOCK (1 << PAGE_CGROUP_LOCK_BIT)
+#else
+#define PAGE_CGROUP_LOCK 0x0
+#endif
/*
* A page_cgroup page is associated with every page descriptor. The
struct list_head lru; /* per cgroup LRU list */
struct page *page;
struct mem_cgroup *mem_cgroup;
+ int ref_cnt; /* cached, mapped, migrating */
+ int flags;
+};
+#define PAGE_CGROUP_FLAG_CACHE (0x1) /* charged as cache */
+#define PAGE_CGROUP_FLAG_ACTIVE (0x2) /* page is active in this cgroup */
+
+static int page_cgroup_nid(struct page_cgroup *pc)
+{
+ return page_to_nid(pc->page);
+}
+
+static enum zone_type page_cgroup_zid(struct page_cgroup *pc)
+{
+ return page_zonenum(pc->page);
+}
+
+enum charge_type {
+ MEM_CGROUP_CHARGE_TYPE_CACHE = 0,
+ MEM_CGROUP_CHARGE_TYPE_MAPPED,
};
+/*
+ * Always modified under lru lock. Then, not necessary to preempt_disable()
+ */
+static void mem_cgroup_charge_statistics(struct mem_cgroup *mem, int flags,
+ bool charge)
+{
+ int val = (charge)? 1 : -1;
+ struct mem_cgroup_stat *stat = &mem->stat;
+
+ VM_BUG_ON(!irqs_disabled());
+ if (flags & PAGE_CGROUP_FLAG_CACHE)
+ __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_CACHE, val);
+ else
+ __mem_cgroup_stat_add_safe(stat, MEM_CGROUP_STAT_RSS, val);
+}
+
+static struct mem_cgroup_per_zone *
+mem_cgroup_zoneinfo(struct mem_cgroup *mem, int nid, int zid)
+{
+ return &mem->info.nodeinfo[nid]->zoneinfo[zid];
+}
+
+static struct mem_cgroup_per_zone *
+page_cgroup_zoneinfo(struct page_cgroup *pc)
+{
+ struct mem_cgroup *mem = pc->mem_cgroup;
+ int nid = page_cgroup_nid(pc);
+ int zid = page_cgroup_zid(pc);
+
+ return mem_cgroup_zoneinfo(mem, nid, zid);
+}
+
+static unsigned long mem_cgroup_get_all_zonestat(struct mem_cgroup *mem,
+ enum mem_cgroup_zstat_index idx)
+{
+ int nid, zid;
+ struct mem_cgroup_per_zone *mz;
+ u64 total = 0;
-static inline
-struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
+ for_each_online_node(nid)
+ for (zid = 0; zid < MAX_NR_ZONES; zid++) {
+ mz = mem_cgroup_zoneinfo(mem, nid, zid);
+ total += MEM_CGROUP_ZSTAT(mz, idx);
+ }
+ return total;
+}
+
+static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
{
return container_of(cgroup_subsys_state(cont,
mem_cgroup_subsys_id), struct mem_cgroup,
css);
}
-static inline
struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
{
return container_of(task_subsys_state(p, mem_cgroup_subsys_id),
struct mem_cgroup, css);
}
-void mm_init_cgroup(struct mm_struct *mm, struct task_struct *p)
+static inline int page_cgroup_locked(struct page *page)
+{
+ return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
+}
+
+static void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
+{
+ VM_BUG_ON(!page_cgroup_locked(page));
+ page->page_cgroup = ((unsigned long)pc | PAGE_CGROUP_LOCK);
+}
+
+struct page_cgroup *page_get_page_cgroup(struct page *page)
+{
+ return (struct page_cgroup *) (page->page_cgroup & ~PAGE_CGROUP_LOCK);
+}
+
+static void lock_page_cgroup(struct page *page)
+{
+ bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
+}
+
+static int try_lock_page_cgroup(struct page *page)
+{
+ return bit_spin_trylock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
+}
+
+static void unlock_page_cgroup(struct page *page)
+{
+ bit_spin_unlock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
+}
+
+static void __mem_cgroup_remove_list(struct mem_cgroup_per_zone *mz,
+ struct page_cgroup *pc)
+{
+ int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
+
+ if (from)
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
+ else
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
+
+ mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, false);
+ list_del_init(&pc->lru);
+}
+
+static void __mem_cgroup_add_list(struct mem_cgroup_per_zone *mz,
+ struct page_cgroup *pc)
+{
+ int to = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
+
+ if (!to) {
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
+ list_add(&pc->lru, &mz->inactive_list);
+ } else {
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
+ list_add(&pc->lru, &mz->active_list);
+ }
+ mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, true);
+}
+
+static void __mem_cgroup_move_lists(struct page_cgroup *pc, bool active)
+{
+ int from = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
+ struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
+
+ if (from)
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) -= 1;
+ else
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) -= 1;
+
+ if (active) {
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE) += 1;
+ pc->flags |= PAGE_CGROUP_FLAG_ACTIVE;
+ list_move(&pc->lru, &mz->active_list);
+ } else {
+ MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE) += 1;
+ pc->flags &= ~PAGE_CGROUP_FLAG_ACTIVE;
+ list_move(&pc->lru, &mz->inactive_list);
+ }
+}
+
+int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
+{
+ int ret;
+
+ task_lock(task);
+ ret = task->mm && mm_match_cgroup(task->mm, mem);
+ task_unlock(task);
+ return ret;
+}
+
+/*
+ * This routine assumes that the appropriate zone's lru lock is already held
+ */
+void mem_cgroup_move_lists(struct page *page, bool active)
+{
+ struct page_cgroup *pc;
+ struct mem_cgroup_per_zone *mz;
+ unsigned long flags;
+
+ /*
+ * We cannot lock_page_cgroup while holding zone's lru_lock,
+ * because other holders of lock_page_cgroup can be interrupted
+ * with an attempt to rotate_reclaimable_page. But we cannot
+ * safely get to page_cgroup without it, so just try_lock it:
+ * mem_cgroup_isolate_pages allows for page left on wrong list.
+ */
+ if (!try_lock_page_cgroup(page))
+ return;
+
+ pc = page_get_page_cgroup(page);
+ if (pc) {
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_move_lists(pc, active);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+ }
+ unlock_page_cgroup(page);
+}
+
+/*
+ * Calculate mapped_ratio under memory controller. This will be used in
+ * vmscan.c for deteremining we have to reclaim mapped pages.
+ */
+int mem_cgroup_calc_mapped_ratio(struct mem_cgroup *mem)
+{
+ long total, rss;
+
+ /*
+ * usage is recorded in bytes. But, here, we assume the number of
+ * physical pages can be represented by "long" on any arch.
+ */
+ total = (long) (mem->res.usage >> PAGE_SHIFT) + 1L;
+ rss = (long)mem_cgroup_read_stat(&mem->stat, MEM_CGROUP_STAT_RSS);
+ return (int)((rss * 100L) / total);
+}
+
+/*
+ * This function is called from vmscan.c. In page reclaiming loop. balance
+ * between active and inactive list is calculated. For memory controller
+ * page reclaiming, we should use using mem_cgroup's imbalance rather than
+ * zone's global lru imbalance.
+ */
+long mem_cgroup_reclaim_imbalance(struct mem_cgroup *mem)
+{
+ unsigned long active, inactive;
+ /* active and inactive are the number of pages. 'long' is ok.*/
+ active = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_ACTIVE);
+ inactive = mem_cgroup_get_all_zonestat(mem, MEM_CGROUP_ZSTAT_INACTIVE);
+ return (long) (active / (inactive + 1));
+}
+
+/*
+ * prev_priority control...this will be used in memory reclaim path.
+ */
+int mem_cgroup_get_reclaim_priority(struct mem_cgroup *mem)
+{
+ return mem->prev_priority;
+}
+
+void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem, int priority)
+{
+ if (priority < mem->prev_priority)
+ mem->prev_priority = priority;
+}
+
+void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
+{
+ mem->prev_priority = priority;
+}
+
+/*
+ * Calculate # of pages to be scanned in this priority/zone.
+ * See also vmscan.c
+ *
+ * priority starts from "DEF_PRIORITY" and decremented in each loop.
+ * (see include/linux/mmzone.h)
+ */
+
+long mem_cgroup_calc_reclaim_active(struct mem_cgroup *mem,
+ struct zone *zone, int priority)
+{
+ long nr_active;
+ int nid = zone->zone_pgdat->node_id;
+ int zid = zone_idx(zone);
+ struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
+
+ nr_active = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_ACTIVE);
+ return (nr_active >> priority);
+}
+
+long mem_cgroup_calc_reclaim_inactive(struct mem_cgroup *mem,
+ struct zone *zone, int priority)
+{
+ long nr_inactive;
+ int nid = zone->zone_pgdat->node_id;
+ int zid = zone_idx(zone);
+ struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
+
+ nr_inactive = MEM_CGROUP_ZSTAT(mz, MEM_CGROUP_ZSTAT_INACTIVE);
+ return (nr_inactive >> priority);
+}
+
+unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
+ struct list_head *dst,
+ unsigned long *scanned, int order,
+ int mode, struct zone *z,
+ struct mem_cgroup *mem_cont,
+ int active)
+{
+ unsigned long nr_taken = 0;
+ struct page *page;
+ unsigned long scan;
+ LIST_HEAD(pc_list);
+ struct list_head *src;
+ struct page_cgroup *pc, *tmp;
+ int nid = z->zone_pgdat->node_id;
+ int zid = zone_idx(z);
+ struct mem_cgroup_per_zone *mz;
+
+ BUG_ON(!mem_cont);
+ mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
+ if (active)
+ src = &mz->active_list;
+ else
+ src = &mz->inactive_list;
+
+
+ spin_lock(&mz->lru_lock);
+ scan = 0;
+ list_for_each_entry_safe_reverse(pc, tmp, src, lru) {
+ if (scan >= nr_to_scan)
+ break;
+ page = pc->page;
+
+ if (unlikely(!PageLRU(page)))
+ continue;
+
+ if (PageActive(page) && !active) {
+ __mem_cgroup_move_lists(pc, true);
+ continue;
+ }
+ if (!PageActive(page) && active) {
+ __mem_cgroup_move_lists(pc, false);
+ continue;
+ }
+
+ scan++;
+ list_move(&pc->lru, &pc_list);
+
+ if (__isolate_lru_page(page, mode) == 0) {
+ list_move(&page->lru, dst);
+ nr_taken++;
+ }
+ }
+
+ list_splice(&pc_list, src);
+ spin_unlock(&mz->lru_lock);
+
+ *scanned = scan;
+ return nr_taken;
+}
+
+/*
+ * Charge the memory controller for page usage.
+ * Return
+ * 0 if the charge was successful
+ * < 0 if the cgroup is over its limit
+ */
+static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask, enum charge_type ctype)
{
struct mem_cgroup *mem;
+ struct page_cgroup *pc;
+ unsigned long flags;
+ unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ struct mem_cgroup_per_zone *mz;
+
+ if (mem_cgroup_subsys.disabled)
+ return 0;
+
+ /*
+ * Should page_cgroup's go to their own slab?
+ * One could optimize the performance of the charging routine
+ * by saving a bit in the page_flags and using it as a lock
+ * to see if the cgroup page already has a page_cgroup associated
+ * with it
+ */
+retry:
+ lock_page_cgroup(page);
+ pc = page_get_page_cgroup(page);
+ /*
+ * The page_cgroup exists and
+ * the page has already been accounted.
+ */
+ if (pc) {
+ VM_BUG_ON(pc->page != page);
+ VM_BUG_ON(pc->ref_cnt <= 0);
+
+ pc->ref_cnt++;
+ unlock_page_cgroup(page);
+ goto done;
+ }
+ unlock_page_cgroup(page);
+
+ pc = kmem_cache_zalloc(page_cgroup_cache, gfp_mask);
+ if (pc == NULL)
+ goto err;
+
+ /*
+ * We always charge the cgroup the mm_struct belongs to.
+ * The mm_struct's mem_cgroup changes on task migration if the
+ * thread group leader migrates. It's possible that mm is not
+ * set, if so charge the init_mm (happens for pagecache usage).
+ */
+ if (!mm)
+ mm = &init_mm;
- mem = mem_cgroup_from_task(p);
+ rcu_read_lock();
+ mem = mem_cgroup_from_task(rcu_dereference(mm->owner));
+ /*
+ * For every charge from the cgroup, increment reference count
+ */
css_get(&mem->css);
- mm->mem_cgroup = mem;
+ rcu_read_unlock();
+
+ while (res_counter_charge(&mem->res, PAGE_SIZE)) {
+ if (!(gfp_mask & __GFP_WAIT))
+ goto out;
+
+ if (try_to_free_mem_cgroup_pages(mem, gfp_mask))
+ continue;
+
+ /*
+ * try_to_free_mem_cgroup_pages() might not give us a full
+ * picture of reclaim. Some pages are reclaimed and might be
+ * moved to swap cache or just unmapped from the cgroup.
+ * Check the limit again to see if the reclaim reduced the
+ * current usage of the cgroup before giving up
+ */
+ if (res_counter_check_under_limit(&mem->res))
+ continue;
+
+ if (!nr_retries--) {
+ mem_cgroup_out_of_memory(mem, gfp_mask);
+ goto out;
+ }
+ }
+
+ pc->ref_cnt = 1;
+ pc->mem_cgroup = mem;
+ pc->page = page;
+ pc->flags = PAGE_CGROUP_FLAG_ACTIVE;
+ if (ctype == MEM_CGROUP_CHARGE_TYPE_CACHE)
+ pc->flags = PAGE_CGROUP_FLAG_CACHE;
+
+ lock_page_cgroup(page);
+ if (page_get_page_cgroup(page)) {
+ unlock_page_cgroup(page);
+ /*
+ * Another charge has been added to this page already.
+ * We take lock_page_cgroup(page) again and read
+ * page->cgroup, increment refcnt.... just retry is OK.
+ */
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
+ css_put(&mem->css);
+ kmem_cache_free(page_cgroup_cache, pc);
+ goto retry;
+ }
+ page_assign_page_cgroup(page, pc);
+
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_add_list(mz, pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+
+ unlock_page_cgroup(page);
+done:
+ return 0;
+out:
+ css_put(&mem->css);
+ kmem_cache_free(page_cgroup_cache, pc);
+err:
+ return -ENOMEM;
}
-void mm_free_cgroup(struct mm_struct *mm)
+int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
{
- css_put(&mm->mem_cgroup->css);
+ return mem_cgroup_charge_common(page, mm, gfp_mask,
+ MEM_CGROUP_CHARGE_TYPE_MAPPED);
}
-void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
+int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask)
{
- page->page_cgroup = (unsigned long)pc;
+ if (!mm)
+ mm = &init_mm;
+ return mem_cgroup_charge_common(page, mm, gfp_mask,
+ MEM_CGROUP_CHARGE_TYPE_CACHE);
}
-struct page_cgroup *page_get_page_cgroup(struct page *page)
+/*
+ * Uncharging is always a welcome operation, we never complain, simply
+ * uncharge.
+ */
+void mem_cgroup_uncharge_page(struct page *page)
+{
+ struct page_cgroup *pc;
+ struct mem_cgroup *mem;
+ struct mem_cgroup_per_zone *mz;
+ unsigned long flags;
+
+ if (mem_cgroup_subsys.disabled)
+ return;
+
+ /*
+ * Check if our page_cgroup is valid
+ */
+ lock_page_cgroup(page);
+ pc = page_get_page_cgroup(page);
+ if (!pc)
+ goto unlock;
+
+ VM_BUG_ON(pc->page != page);
+ VM_BUG_ON(pc->ref_cnt <= 0);
+
+ if (--(pc->ref_cnt) == 0) {
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_remove_list(mz, pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+
+ page_assign_page_cgroup(page, NULL);
+ unlock_page_cgroup(page);
+
+ mem = pc->mem_cgroup;
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
+ css_put(&mem->css);
+
+ kmem_cache_free(page_cgroup_cache, pc);
+ return;
+ }
+
+unlock:
+ unlock_page_cgroup(page);
+}
+
+/*
+ * Returns non-zero if a page (under migration) has valid page_cgroup member.
+ * Refcnt of page_cgroup is incremented.
+ */
+int mem_cgroup_prepare_migration(struct page *page)
+{
+ struct page_cgroup *pc;
+
+ if (mem_cgroup_subsys.disabled)
+ return 0;
+
+ lock_page_cgroup(page);
+ pc = page_get_page_cgroup(page);
+ if (pc)
+ pc->ref_cnt++;
+ unlock_page_cgroup(page);
+ return pc != NULL;
+}
+
+void mem_cgroup_end_migration(struct page *page)
+{
+ mem_cgroup_uncharge_page(page);
+}
+
+/*
+ * We know both *page* and *newpage* are now not-on-LRU and PG_locked.
+ * And no race with uncharge() routines because page_cgroup for *page*
+ * has extra one reference by mem_cgroup_prepare_migration.
+ */
+void mem_cgroup_page_migration(struct page *page, struct page *newpage)
{
- return page->page_cgroup;
+ struct page_cgroup *pc;
+ struct mem_cgroup_per_zone *mz;
+ unsigned long flags;
+
+ lock_page_cgroup(page);
+ pc = page_get_page_cgroup(page);
+ if (!pc) {
+ unlock_page_cgroup(page);
+ return;
+ }
+
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_remove_list(mz, pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+
+ page_assign_page_cgroup(page, NULL);
+ unlock_page_cgroup(page);
+
+ pc->page = newpage;
+ lock_page_cgroup(newpage);
+ page_assign_page_cgroup(newpage, pc);
+
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_add_list(mz, pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+
+ unlock_page_cgroup(newpage);
}
-static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft,
- struct file *file, char __user *userbuf, size_t nbytes,
- loff_t *ppos)
+/*
+ * This routine traverse page_cgroup in given list and drop them all.
+ * This routine ignores page_cgroup->ref_cnt.
+ * *And* this routine doesn't reclaim page itself, just removes page_cgroup.
+ */
+#define FORCE_UNCHARGE_BATCH (128)
+static void mem_cgroup_force_empty_list(struct mem_cgroup *mem,
+ struct mem_cgroup_per_zone *mz,
+ int active)
{
- return res_counter_read(&mem_cgroup_from_cont(cont)->res,
- cft->private, userbuf, nbytes, ppos);
+ struct page_cgroup *pc;
+ struct page *page;
+ int count = FORCE_UNCHARGE_BATCH;
+ unsigned long flags;
+ struct list_head *list;
+
+ if (active)
+ list = &mz->active_list;
+ else
+ list = &mz->inactive_list;
+
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ while (!list_empty(list)) {
+ pc = list_entry(list->prev, struct page_cgroup, lru);
+ page = pc->page;
+ get_page(page);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+ mem_cgroup_uncharge_page(page);
+ put_page(page);
+ if (--count <= 0) {
+ count = FORCE_UNCHARGE_BATCH;
+ cond_resched();
+ }
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ }
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+}
+
+/*
+ * make mem_cgroup's charge to be 0 if there is no task.
+ * This enables deleting this mem_cgroup.
+ */
+static int mem_cgroup_force_empty(struct mem_cgroup *mem)
+{
+ int ret = -EBUSY;
+ int node, zid;
+
+ if (mem_cgroup_subsys.disabled)
+ return 0;
+
+ css_get(&mem->css);
+ /*
+ * page reclaim code (kswapd etc..) will move pages between
+ * active_list <-> inactive_list while we don't take a lock.
+ * So, we have to do loop here until all lists are empty.
+ */
+ while (mem->res.usage > 0) {
+ if (atomic_read(&mem->css.cgroup->count) > 0)
+ goto out;
+ for_each_node_state(node, N_POSSIBLE)
+ for (zid = 0; zid < MAX_NR_ZONES; zid++) {
+ struct mem_cgroup_per_zone *mz;
+ mz = mem_cgroup_zoneinfo(mem, node, zid);
+ /* drop all page_cgroup in active_list */
+ mem_cgroup_force_empty_list(mem, mz, 1);
+ /* drop all page_cgroup in inactive_list */
+ mem_cgroup_force_empty_list(mem, mz, 0);
+ }
+ }
+ ret = 0;
+out:
+ css_put(&mem->css);
+ return ret;
+}
+
+static int mem_cgroup_write_strategy(char *buf, unsigned long long *tmp)
+{
+ *tmp = memparse(buf, &buf);
+ if (*buf != '\0')
+ return -EINVAL;
+
+ /*
+ * Round up the value to the closest page size
+ */
+ *tmp = ((*tmp + PAGE_SIZE - 1) >> PAGE_SHIFT) << PAGE_SHIFT;
+ return 0;
+}
+
+static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
+{
+ return res_counter_read_u64(&mem_cgroup_from_cont(cont)->res,
+ cft->private);
}
static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
size_t nbytes, loff_t *ppos)
{
return res_counter_write(&mem_cgroup_from_cont(cont)->res,
- cft->private, userbuf, nbytes, ppos);
+ cft->private, userbuf, nbytes, ppos,
+ mem_cgroup_write_strategy);
+}
+
+static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
+{
+ struct mem_cgroup *mem;
+
+ mem = mem_cgroup_from_cont(cont);
+ switch (event) {
+ case RES_MAX_USAGE:
+ res_counter_reset_max(&mem->res);
+ break;
+ case RES_FAILCNT:
+ res_counter_reset_failcnt(&mem->res);
+ break;
+ }
+ return 0;
+}
+
+static int mem_force_empty_write(struct cgroup *cont, unsigned int event)
+{
+ return mem_cgroup_force_empty(mem_cgroup_from_cont(cont));
+}
+
+static const struct mem_cgroup_stat_desc {
+ const char *msg;
+ u64 unit;
+} mem_cgroup_stat_desc[] = {
+ [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
+ [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
+};
+
+static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft,
+ struct cgroup_map_cb *cb)
+{
+ struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
+ struct mem_cgroup_stat *stat = &mem_cont->stat;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
+ s64 val;
+
+ val = mem_cgroup_read_stat(stat, i);
+ val *= mem_cgroup_stat_desc[i].unit;
+ cb->fill(cb, mem_cgroup_stat_desc[i].msg, val);
+ }
+ /* showing # of active pages */
+ {
+ unsigned long active, inactive;
+
+ inactive = mem_cgroup_get_all_zonestat(mem_cont,
+ MEM_CGROUP_ZSTAT_INACTIVE);
+ active = mem_cgroup_get_all_zonestat(mem_cont,
+ MEM_CGROUP_ZSTAT_ACTIVE);
+ cb->fill(cb, "active", (active) * PAGE_SIZE);
+ cb->fill(cb, "inactive", (inactive) * PAGE_SIZE);
+ }
+ return 0;
}
static struct cftype mem_cgroup_files[] = {
{
- .name = "usage",
+ .name = "usage_in_bytes",
.private = RES_USAGE,
- .read = mem_cgroup_read,
+ .read_u64 = mem_cgroup_read,
+ },
+ {
+ .name = "max_usage_in_bytes",
+ .private = RES_MAX_USAGE,
+ .trigger = mem_cgroup_reset,
+ .read_u64 = mem_cgroup_read,
},
{
- .name = "limit",
+ .name = "limit_in_bytes",
.private = RES_LIMIT,
.write = mem_cgroup_write,
- .read = mem_cgroup_read,
+ .read_u64 = mem_cgroup_read,
},
{
.name = "failcnt",
.private = RES_FAILCNT,
- .read = mem_cgroup_read,
+ .trigger = mem_cgroup_reset,
+ .read_u64 = mem_cgroup_read,
+ },
+ {
+ .name = "force_empty",
+ .trigger = mem_force_empty_write,
+ },
+ {
+ .name = "stat",
+ .read_map = mem_control_stat_show,
},
};
-static struct mem_cgroup init_mem_cgroup;
+static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
+{
+ struct mem_cgroup_per_node *pn;
+ struct mem_cgroup_per_zone *mz;
+ int zone, tmp = node;
+ /*
+ * This routine is called against possible nodes.
+ * But it's BUG to call kmalloc() against offline node.
+ *
+ * TODO: this routine can waste much memory for nodes which will
+ * never be onlined. It's better to use memory hotplug callback
+ * function.
+ */
+ if (!node_state(node, N_NORMAL_MEMORY))
+ tmp = -1;
+ pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, tmp);
+ if (!pn)
+ return 1;
+
+ mem->info.nodeinfo[node] = pn;
+ memset(pn, 0, sizeof(*pn));
+
+ for (zone = 0; zone < MAX_NR_ZONES; zone++) {
+ mz = &pn->zoneinfo[zone];
+ INIT_LIST_HEAD(&mz->active_list);
+ INIT_LIST_HEAD(&mz->inactive_list);
+ spin_lock_init(&mz->lru_lock);
+ }
+ return 0;
+}
+
+static void free_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
+{
+ kfree(mem->info.nodeinfo[node]);
+}
+
+static struct mem_cgroup *mem_cgroup_alloc(void)
+{
+ struct mem_cgroup *mem;
+
+ if (sizeof(*mem) < PAGE_SIZE)
+ mem = kmalloc(sizeof(*mem), GFP_KERNEL);
+ else
+ mem = vmalloc(sizeof(*mem));
+
+ if (mem)
+ memset(mem, 0, sizeof(*mem));
+ return mem;
+}
+
+static void mem_cgroup_free(struct mem_cgroup *mem)
+{
+ if (sizeof(*mem) < PAGE_SIZE)
+ kfree(mem);
+ else
+ vfree(mem);
+}
+
static struct cgroup_subsys_state *
mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
{
struct mem_cgroup *mem;
+ int node;
if (unlikely((cont->parent) == NULL)) {
mem = &init_mem_cgroup;
- init_mm.mem_cgroup = mem;
- } else
- mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);
-
- if (mem == NULL)
- return NULL;
+ page_cgroup_cache = KMEM_CACHE(page_cgroup, SLAB_PANIC);
+ } else {
+ mem = mem_cgroup_alloc();
+ if (!mem)
+ return ERR_PTR(-ENOMEM);
+ }
res_counter_init(&mem->res);
+
+ for_each_node_state(node, N_POSSIBLE)
+ if (alloc_mem_cgroup_per_zone_info(mem, node))
+ goto free_out;
+
return &mem->css;
+free_out:
+ for_each_node_state(node, N_POSSIBLE)
+ free_mem_cgroup_per_zone_info(mem, node);
+ if (cont->parent != NULL)
+ mem_cgroup_free(mem);
+ return ERR_PTR(-ENOMEM);
+}
+
+static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
+ struct cgroup *cont)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
+ mem_cgroup_force_empty(mem);
}
static void mem_cgroup_destroy(struct cgroup_subsys *ss,
struct cgroup *cont)
{
- kfree(mem_cgroup_from_cont(cont));
+ int node;
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
+
+ for_each_node_state(node, N_POSSIBLE)
+ free_mem_cgroup_per_zone_info(mem, node);
+
+ mem_cgroup_free(mem_cgroup_from_cont(cont));
}
static int mem_cgroup_populate(struct cgroup_subsys *ss,
struct cgroup *cont)
{
+ if (mem_cgroup_subsys.disabled)
+ return 0;
return cgroup_add_files(cont, ss, mem_cgroup_files,
ARRAY_SIZE(mem_cgroup_files));
}
+static void mem_cgroup_move_task(struct cgroup_subsys *ss,
+ struct cgroup *cont,
+ struct cgroup *old_cont,
+ struct task_struct *p)
+{
+ struct mm_struct *mm;
+ struct mem_cgroup *mem, *old_mem;
+
+ if (mem_cgroup_subsys.disabled)
+ return;
+
+ mm = get_task_mm(p);
+ if (mm == NULL)
+ return;
+
+ mem = mem_cgroup_from_cont(cont);
+ old_mem = mem_cgroup_from_cont(old_cont);
+
+ if (mem == old_mem)
+ goto out;
+
+ /*
+ * Only thread group leaders are allowed to migrate, the mm_struct is
+ * in effect owned by the leader
+ */
+ if (!thread_group_leader(p))
+ goto out;
+
+out:
+ mmput(mm);
+}
+
struct cgroup_subsys mem_cgroup_subsys = {
.name = "memory",
.subsys_id = mem_cgroup_subsys_id,
.create = mem_cgroup_create,
+ .pre_destroy = mem_cgroup_pre_destroy,
.destroy = mem_cgroup_destroy,
.populate = mem_cgroup_populate,
- .early_init = 1,
+ .attach = mem_cgroup_move_task,
+ .early_init = 0,
};
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff