#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/swap.h>
#include <linux/spinlock.h>
#include <linux/fs.h>
+#include <linux/seq_file.h>
#include <asm/uaccess.h>
struct cgroup_subsys mem_cgroup_subsys;
static const int MEM_CGROUP_RECLAIM_RETRIES = 5;
+/*
+ * 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
* page cache and RSS per cgroup. We would eventually like to provide
/*
* 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 */
/*
- * spin_lock to protect the per cgroup LRU
+ * statistics.
*/
- spinlock_t lru_lock;
- unsigned long control_type; /* control RSS or RSS+Pagecache */
+ 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 atleast two
- * byte aligned (based on comments from Nick Piggin)
+ * 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
-#define PAGE_CGROUP_LOCK (1 << PAGE_CGROUP_LOCK_BIT)
+#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;
- atomic_t ref_cnt; /* Helpful when pages move b/w */
- /* mapped and cached states */
+ 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);
+}
-enum {
- MEM_CGROUP_TYPE_UNSPEC = 0,
- MEM_CGROUP_TYPE_MAPPED,
- MEM_CGROUP_TYPE_CACHED,
- MEM_CGROUP_TYPE_ALL,
- MEM_CGROUP_TYPE_MAX,
+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,
};
-static struct mem_cgroup init_mem_cgroup;
+/*
+ * 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 inline
-struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
+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;
+
+ 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)
+static 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);
static inline int page_cgroup_locked(struct page *page)
{
- return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT,
- &page->page_cgroup);
+ return bit_spin_is_locked(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
}
-void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
+static void page_assign_page_cgroup(struct page *page, struct page_cgroup *pc)
{
- int locked;
-
- /*
- * While resetting the page_cgroup we might not hold the
- * page_cgroup lock. free_hot_cold_page() is an example
- * of such a scenario
- */
- if (pc)
- VM_BUG_ON(!page_cgroup_locked(page));
- locked = (page->page_cgroup & PAGE_CGROUP_LOCK);
- page->page_cgroup = ((unsigned long)pc | locked);
+ 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);
+ return (struct page_cgroup *) (page->page_cgroup & ~PAGE_CGROUP_LOCK);
}
-static void __always_inline lock_page_cgroup(struct page *page)
+static void lock_page_cgroup(struct page *page)
{
bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup);
- VM_BUG_ON(!page_cgroup_locked(page));
}
-static void __always_inline unlock_page_cgroup(struct page *page)
+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 page_cgroup *pc)
+{
+ 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;
+
+ mem_cgroup_charge_statistics(pc->mem_cgroup, pc->flags, false);
+ list_del_init(&pc->lru);
+}
+
+static void __mem_cgroup_add_list(struct page_cgroup *pc)
+{
+ int to = pc->flags & PAGE_CGROUP_FLAG_ACTIVE;
+ struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
+
+ 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)
{
- if (active)
- list_move(&pc->lru, &pc->mem_cgroup->active_list);
+ 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
- list_move(&pc->lru, &pc->mem_cgroup->inactive_list);
+ 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_cgroup(task->mm) == mem;
+ 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_cgroup *pc, bool active)
+void mem_cgroup_move_lists(struct page *page, bool active)
{
- struct mem_cgroup *mem;
- if (!pc)
+ 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;
- mem = pc->mem_cgroup;
+ 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);
+}
- spin_lock(&mem->lru_lock);
- __mem_cgroup_move_lists(pc, active);
- spin_unlock(&mem->lru_lock);
+/*
+ * 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,
unsigned long scan;
LIST_HEAD(pc_list);
struct list_head *src;
- struct page_cgroup *pc;
+ struct page_cgroup *pc, *tmp;
+ int nid = z->zone_pgdat->node_id;
+ int zid = zone_idx(z);
+ struct mem_cgroup_per_zone *mz;
+ mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
if (active)
- src = &mem_cont->active_list;
+ src = &mz->active_list;
else
- src = &mem_cont->inactive_list;
+ src = &mz->inactive_list;
- spin_lock(&mem_cont->lru_lock);
- for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) {
- pc = list_entry(src->prev, struct page_cgroup, lru);
+
+ 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;
- VM_BUG_ON(!pc);
+
+ if (unlikely(!PageLRU(page)))
+ continue;
if (PageActive(page) && !active) {
__mem_cgroup_move_lists(pc, true);
- scan--;
continue;
}
if (!PageActive(page) && active) {
__mem_cgroup_move_lists(pc, false);
- scan--;
continue;
}
- /*
- * Reclaim, per zone
- * TODO: make the active/inactive lists per zone
- */
- if (page_zone(page) != z)
- continue;
-
- /*
- * Check if the meta page went away from under us
- */
- if (!list_empty(&pc->lru))
- list_move(&pc->lru, &pc_list);
- else
- continue;
+ scan++;
+ list_move(&pc->lru, &pc_list);
if (__isolate_lru_page(page, mode) == 0) {
list_move(&page->lru, dst);
}
list_splice(&pc_list, src);
- spin_unlock(&mem_cont->lru_lock);
+ spin_unlock(&mz->lru_lock);
*scanned = scan;
return nr_taken;
* 0 if the charge was successful
* < 0 if the cgroup is over its limit
*/
-int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
- gfp_t gfp_mask)
+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, *race_pc;
+ struct page_cgroup *pc;
unsigned long flags;
unsigned long nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ struct mem_cgroup_per_zone *mz;
/*
* Should page_cgroup's go to their own slab?
lock_page_cgroup(page);
pc = page_get_page_cgroup(page);
/*
- * The page_cgroup exists and the page has already been accounted
+ * The page_cgroup exists and
+ * the page has already been accounted.
*/
if (pc) {
- if (unlikely(!atomic_inc_not_zero(&pc->ref_cnt))) {
- /* this page is under being uncharged ? */
- unlock_page_cgroup(page);
- cpu_relax();
- goto retry;
- } else
- goto done;
- }
+ 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 = kzalloc(sizeof(struct page_cgroup), gfp_mask);
if (pc == NULL)
goto err;
- rcu_read_lock();
/*
- * We always charge the cgroup the mm_struct belongs to
- * the mm_struct's mem_cgroup changes on task migration if the
+ * 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;
+ rcu_read_lock();
mem = rcu_dereference(mm->mem_cgroup);
/*
- * For every charge from the cgroup, increment reference
- * count
+ * For every charge from the cgroup, increment reference count
*/
css_get(&mem->css);
rcu_read_unlock();
- /*
- * If we created the page_cgroup, we should free it on exceeding
- * the cgroup limit.
- */
while (res_counter_charge(&mem->res, PAGE_SIZE)) {
- bool is_atomic = gfp_mask & GFP_ATOMIC;
- /*
- * We cannot reclaim under GFP_ATOMIC, fail the charge
- */
- if (is_atomic)
- goto noreclaim;
+ 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
- */
+ * 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;
- /*
- * Since we control both RSS and cache, we end up with a
- * very interesting scenario where we end up reclaiming
- * memory (essentially RSS), since the memory is pushed
- * to swap cache, we eventually end up adding those
- * pages back to our list. Hence we give ourselves a
- * few chances before we fail
- */
- else if (nr_retries--) {
- congestion_wait(WRITE, HZ/10);
- continue;
+
+ if (!nr_retries--) {
+ mem_cgroup_out_of_memory(mem, gfp_mask);
+ goto out;
}
-noreclaim:
- css_put(&mem->css);
- if (!is_atomic)
- mem_cgroup_out_of_memory(mem, GFP_KERNEL);
- goto free_pc;
+ congestion_wait(WRITE, HZ/10);
}
+ 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);
- /*
- * Check if somebody else beat us to allocating the page_cgroup
- */
- race_pc = page_get_page_cgroup(page);
- if (race_pc) {
- kfree(pc);
- pc = race_pc;
- atomic_inc(&pc->ref_cnt);
+ 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);
- goto done;
+ kfree(pc);
+ goto retry;
}
-
- atomic_set(&pc->ref_cnt, 1);
- pc->mem_cgroup = mem;
- pc->page = page;
page_assign_page_cgroup(page, pc);
- spin_lock_irqsave(&mem->lru_lock, flags);
- list_add(&pc->lru, &mem->active_list);
- spin_unlock_irqrestore(&mem->lru_lock, flags);
+ mz = page_cgroup_zoneinfo(pc);
+ spin_lock_irqsave(&mz->lru_lock, flags);
+ __mem_cgroup_add_list(pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
-done:
unlock_page_cgroup(page);
+done:
return 0;
-free_pc:
+out:
+ css_put(&mem->css);
kfree(pc);
err:
return -ENOMEM;
}
-/*
- * See if the cached pages should be charged at all?
- */
+int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
+{
+ return mem_cgroup_charge_common(page, mm, gfp_mask,
+ MEM_CGROUP_CHARGE_TYPE_MAPPED);
+}
+
int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
gfp_t gfp_mask)
{
- struct mem_cgroup *mem;
if (!mm)
mm = &init_mm;
-
- mem = rcu_dereference(mm->mem_cgroup);
- if (mem->control_type == MEM_CGROUP_TYPE_ALL)
- return mem_cgroup_charge(page, mm, gfp_mask);
- else
- return 0;
+ return mem_cgroup_charge_common(page, mm, gfp_mask,
+ MEM_CGROUP_CHARGE_TYPE_CACHE);
}
/*
* Uncharging is always a welcome operation, we never complain, simply
* uncharge.
*/
-void mem_cgroup_uncharge(struct page_cgroup *pc)
+void mem_cgroup_uncharge_page(struct page *page)
{
+ struct page_cgroup *pc;
struct mem_cgroup *mem;
- struct page *page;
+ struct mem_cgroup_per_zone *mz;
unsigned long flags;
/*
- * This can handle cases when a page is not charged at all and we
- * are switching between handling the control_type.
+ * Check if our page_cgroup is valid
*/
+ lock_page_cgroup(page);
+ pc = page_get_page_cgroup(page);
if (!pc)
- return;
+ 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(pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
- if (atomic_dec_and_test(&pc->ref_cnt)) {
- page = pc->page;
- lock_page_cgroup(page);
- mem = pc->mem_cgroup;
- css_put(&mem->css);
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);
- spin_lock_irqsave(&mem->lru_lock, flags);
- list_del_init(&pc->lru);
- spin_unlock_irqrestore(&mem->lru_lock, flags);
kfree(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;
+
+ 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)
+{
+ 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(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(pc);
+ spin_unlock_irqrestore(&mz->lru_lock, flags);
+
+ unlock_page_cgroup(newpage);
+}
+
+/*
+ * 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)
+{
+ 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);
}
-int mem_cgroup_write_strategy(char *buf, unsigned long long *tmp)
+/*
+ * 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;
+
+ 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')
mem_cgroup_write_strategy);
}
-static ssize_t mem_control_type_write(struct cgroup *cont,
- struct cftype *cft, struct file *file,
- const char __user *userbuf,
- size_t nbytes, loff_t *pos)
+static ssize_t mem_force_empty_write(struct cgroup *cont,
+ struct cftype *cft, struct file *file,
+ const char __user *userbuf,
+ size_t nbytes, loff_t *ppos)
{
- int ret;
- char *buf, *end;
- unsigned long tmp;
- struct mem_cgroup *mem;
-
- mem = mem_cgroup_from_cont(cont);
- buf = kmalloc(nbytes + 1, GFP_KERNEL);
- ret = -ENOMEM;
- if (buf == NULL)
- goto out;
-
- buf[nbytes] = 0;
- ret = -EFAULT;
- if (copy_from_user(buf, userbuf, nbytes))
- goto out_free;
-
- ret = -EINVAL;
- tmp = simple_strtoul(buf, &end, 10);
- if (*end != '\0')
- goto out_free;
-
- if (tmp <= MEM_CGROUP_TYPE_UNSPEC || tmp >= MEM_CGROUP_TYPE_MAX)
- goto out_free;
-
- mem->control_type = tmp;
- ret = nbytes;
-out_free:
- kfree(buf);
-out:
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
+ int ret = mem_cgroup_force_empty(mem);
+ if (!ret)
+ ret = nbytes;
return ret;
}
-static ssize_t mem_control_type_read(struct cgroup *cont,
+/*
+ * Note: This should be removed if cgroup supports write-only file.
+ */
+static ssize_t mem_force_empty_read(struct cgroup *cont,
struct cftype *cft,
struct file *file, char __user *userbuf,
size_t nbytes, loff_t *ppos)
{
- unsigned long val;
- char buf[64], *s;
- struct mem_cgroup *mem;
+ return -EINVAL;
+}
- mem = mem_cgroup_from_cont(cont);
- s = buf;
- val = mem->control_type;
- s += sprintf(s, "%lu\n", val);
- return simple_read_from_buffer((void __user *)userbuf, nbytes,
- ppos, buf, s - buf);
+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 seq_file *m, void *arg)
+{
+ struct cgroup *cont = m->private;
+ 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;
+ seq_printf(m, "%s %lld\n", mem_cgroup_stat_desc[i].msg,
+ (long long)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);
+ seq_printf(m, "active %ld\n", (active) * PAGE_SIZE);
+ seq_printf(m, "inactive %ld\n", (inactive) * PAGE_SIZE);
+ }
+ return 0;
+}
+
+static const struct file_operations mem_control_stat_file_operations = {
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int mem_control_stat_open(struct inode *unused, struct file *file)
+{
+ /* XXX __d_cont */
+ struct cgroup *cont = file->f_dentry->d_parent->d_fsdata;
+
+ file->f_op = &mem_control_stat_file_operations;
+ return single_open(file, mem_control_stat_show, cont);
}
static struct cftype mem_cgroup_files[] = {
.read = mem_cgroup_read,
},
{
- .name = "control_type",
- .write = mem_control_type_write,
- .read = mem_control_type_read,
+ .name = "force_empty",
+ .write = mem_force_empty_write,
+ .read = mem_force_empty_read,
+ },
+ {
+ .name = "stat",
+ .open = mem_control_stat_open,
},
};
-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;
+ /*
+ * 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_HIGH_MEMORY))
+ pn = kmalloc_node(sizeof(*pn), GFP_KERNEL, node);
+ else
+ pn = kmalloc(sizeof(*pn), GFP_KERNEL);
+ 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 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;
mem = kzalloc(sizeof(struct mem_cgroup), GFP_KERNEL);
if (mem == NULL)
- return NULL;
+ return ERR_PTR(-ENOMEM);
res_counter_init(&mem->res);
- INIT_LIST_HEAD(&mem->active_list);
- INIT_LIST_HEAD(&mem->inactive_list);
- spin_lock_init(&mem->lru_lock);
- mem->control_type = MEM_CGROUP_TYPE_ALL;
+
+ memset(&mem->info, 0, sizeof(mem->info));
+
+ 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)
+ kfree(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)
{
+ 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);
+
kfree(mem_cgroup_from_cont(cont));
}
out:
mmput(mm);
- return;
}
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,
.attach = mem_cgroup_move_task,
- .early_init = 1,
+ .early_init = 0,
};