#include <linux/vmalloc.h>
#include <linux/mm_inline.h>
#include <linux/page_cgroup.h>
+#include "internal.h"
#include <asm/uaccess.h>
/*
* spin_lock to protect the per cgroup LRU
*/
- spinlock_t lru_lock;
struct list_head lists[NR_LRU_LISTS];
unsigned long count[NR_LRU_LISTS];
};
/* only for here (for easy reading.) */
#define PCGF_CACHE (1UL << PCG_CACHE)
#define PCGF_USED (1UL << PCG_USED)
-#define PCGF_ACTIVE (1UL << PCG_ACTIVE)
#define PCGF_LOCK (1UL << PCG_LOCK)
-#define PCGF_FILE (1UL << PCG_FILE)
static const unsigned long
pcg_default_flags[NR_CHARGE_TYPE] = {
- PCGF_CACHE | PCGF_FILE | PCGF_USED | PCGF_LOCK, /* File Cache */
- PCGF_ACTIVE | PCGF_USED | PCGF_LOCK, /* Anon */
- PCGF_ACTIVE | PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* Shmem */
+ PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* File Cache */
+ PCGF_USED | PCGF_LOCK, /* Anon */
+ PCGF_CACHE | PCGF_USED | PCGF_LOCK, /* Shmem */
0, /* FORCE */
};
static void mem_cgroup_get(struct mem_cgroup *mem);
static void mem_cgroup_put(struct mem_cgroup *mem);
-/*
- * Always modified under lru lock. Then, not necessary to preempt_disable()
- */
static void mem_cgroup_charge_statistics(struct mem_cgroup *mem,
struct page_cgroup *pc,
bool charge)
int val = (charge)? 1 : -1;
struct mem_cgroup_stat *stat = &mem->stat;
struct mem_cgroup_stat_cpu *cpustat;
+ int cpu = get_cpu();
- VM_BUG_ON(!irqs_disabled());
-
- cpustat = &stat->cpustat[smp_processor_id()];
+ cpustat = &stat->cpustat[cpu];
if (PageCgroupCache(pc))
__mem_cgroup_stat_add_safe(cpustat, MEM_CGROUP_STAT_CACHE, val);
else
else
__mem_cgroup_stat_add_safe(cpustat,
MEM_CGROUP_STAT_PGPGOUT_COUNT, 1);
+ put_cpu();
}
static struct mem_cgroup_per_zone *
struct mem_cgroup, css);
}
-static void __mem_cgroup_remove_list(struct mem_cgroup_per_zone *mz,
- struct page_cgroup *pc)
-{
- int lru = LRU_BASE;
+/*
+ * Following LRU functions are allowed to be used without PCG_LOCK.
+ * Operations are called by routine of global LRU independently from memcg.
+ * What we have to take care of here is validness of pc->mem_cgroup.
+ *
+ * Changes to pc->mem_cgroup happens when
+ * 1. charge
+ * 2. moving account
+ * In typical case, "charge" is done before add-to-lru. Exception is SwapCache.
+ * It is added to LRU before charge.
+ * If PCG_USED bit is not set, page_cgroup is not added to this private LRU.
+ * When moving account, the page is not on LRU. It's isolated.
+ */
- if (PageCgroupUnevictable(pc))
- lru = LRU_UNEVICTABLE;
- else {
- if (PageCgroupActive(pc))
- lru += LRU_ACTIVE;
- if (PageCgroupFile(pc))
- lru += LRU_FILE;
- }
+void mem_cgroup_del_lru_list(struct page *page, enum lru_list lru)
+{
+ struct page_cgroup *pc;
+ struct mem_cgroup *mem;
+ struct mem_cgroup_per_zone *mz;
+ if (mem_cgroup_subsys.disabled)
+ return;
+ pc = lookup_page_cgroup(page);
+ /* can happen while we handle swapcache. */
+ if (list_empty(&pc->lru))
+ return;
+ mz = page_cgroup_zoneinfo(pc);
+ mem = pc->mem_cgroup;
MEM_CGROUP_ZSTAT(mz, lru) -= 1;
-
- mem_cgroup_charge_statistics(pc->mem_cgroup, pc, false);
- list_del(&pc->lru);
+ list_del_init(&pc->lru);
+ return;
}
-static void __mem_cgroup_add_list(struct mem_cgroup_per_zone *mz,
- struct page_cgroup *pc, bool hot)
+void mem_cgroup_del_lru(struct page *page)
{
- int lru = LRU_BASE;
+ mem_cgroup_del_lru_list(page, page_lru(page));
+}
- if (PageCgroupUnevictable(pc))
- lru = LRU_UNEVICTABLE;
- else {
- if (PageCgroupActive(pc))
- lru += LRU_ACTIVE;
- if (PageCgroupFile(pc))
- lru += LRU_FILE;
- }
+void mem_cgroup_rotate_lru_list(struct page *page, enum lru_list lru)
+{
+ struct mem_cgroup_per_zone *mz;
+ struct page_cgroup *pc;
- MEM_CGROUP_ZSTAT(mz, lru) += 1;
- if (hot)
- list_add(&pc->lru, &mz->lists[lru]);
- else
- list_add_tail(&pc->lru, &mz->lists[lru]);
+ if (mem_cgroup_subsys.disabled)
+ return;
- mem_cgroup_charge_statistics(pc->mem_cgroup, pc, true);
+ pc = lookup_page_cgroup(page);
+ smp_rmb();
+ /* unused page is not rotated. */
+ if (!PageCgroupUsed(pc))
+ return;
+ mz = page_cgroup_zoneinfo(pc);
+ list_move(&pc->lru, &mz->lists[lru]);
}
-static void __mem_cgroup_move_lists(struct page_cgroup *pc, enum lru_list lru)
+void mem_cgroup_add_lru_list(struct page *page, enum lru_list lru)
{
- struct mem_cgroup_per_zone *mz = page_cgroup_zoneinfo(pc);
- int active = PageCgroupActive(pc);
- int file = PageCgroupFile(pc);
- int unevictable = PageCgroupUnevictable(pc);
- enum lru_list from = unevictable ? LRU_UNEVICTABLE :
- (LRU_FILE * !!file + !!active);
+ struct page_cgroup *pc;
+ struct mem_cgroup_per_zone *mz;
- if (lru == from)
+ if (mem_cgroup_subsys.disabled)
+ return;
+ pc = lookup_page_cgroup(page);
+ /* barrier to sync with "charge" */
+ smp_rmb();
+ if (!PageCgroupUsed(pc))
return;
- MEM_CGROUP_ZSTAT(mz, from) -= 1;
- /*
- * However this is done under mz->lru_lock, another flags, which
- * are not related to LRU, will be modified from out-of-lock.
- * We have to use atomic set/clear flags.
- */
- if (is_unevictable_lru(lru)) {
- ClearPageCgroupActive(pc);
- SetPageCgroupUnevictable(pc);
- } else {
- if (is_active_lru(lru))
- SetPageCgroupActive(pc);
- else
- ClearPageCgroupActive(pc);
- ClearPageCgroupUnevictable(pc);
- }
-
+ mz = page_cgroup_zoneinfo(pc);
MEM_CGROUP_ZSTAT(mz, lru) += 1;
- list_move(&pc->lru, &mz->lists[lru]);
+ list_add(&pc->lru, &mz->lists[lru]);
+}
+/*
+ * To add swapcache into LRU. Be careful to all this function.
+ * zone->lru_lock shouldn't be held and irq must not be disabled.
+ */
+static void mem_cgroup_lru_fixup(struct page *page)
+{
+ if (!isolate_lru_page(page))
+ putback_lru_page(page);
+}
+
+void mem_cgroup_move_lists(struct page *page,
+ enum lru_list from, enum lru_list to)
+{
+ if (mem_cgroup_subsys.disabled)
+ return;
+ mem_cgroup_del_lru_list(page, from);
+ mem_cgroup_add_lru_list(page, to);
}
int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem)
return ret;
}
-/*
- * This routine assumes that the appropriate zone's lru lock is already held
- */
-void mem_cgroup_move_lists(struct page *page, enum lru_list lru)
-{
- struct page_cgroup *pc;
- struct mem_cgroup_per_zone *mz;
- unsigned long flags;
-
- if (mem_cgroup_subsys.disabled)
- return;
-
- /*
- * 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.
- */
- pc = lookup_page_cgroup(page);
- if (!trylock_page_cgroup(pc))
- return;
- if (pc && PageCgroupUsed(pc)) {
- mz = page_cgroup_zoneinfo(pc);
- spin_lock_irqsave(&mz->lru_lock, flags);
- __mem_cgroup_move_lists(pc, lru);
- spin_unlock_irqrestore(&mz->lru_lock, flags);
- }
- unlock_page_cgroup(pc);
-}
-
/*
* Calculate mapped_ratio under memory controller. This will be used in
* vmscan.c for deteremining we have to reclaim mapped pages.
mz = mem_cgroup_zoneinfo(mem_cont, nid, zid);
src = &mz->lists[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;
if (unlikely(!PageCgroupUsed(pc)))
continue;
- page = pc->page;
-
if (unlikely(!PageLRU(page)))
continue;
- /*
- * TODO: play better with lumpy reclaim, grabbing anything.
- */
- if (PageUnevictable(page) ||
- (PageActive(page) && !active) ||
- (!PageActive(page) && active)) {
- __mem_cgroup_move_lists(pc, page_lru(page));
- continue;
- }
-
scan++;
- list_move(&pc->lru, &pc_list);
-
if (__isolate_lru_page(page, mode, file) == 0) {
list_move(&page->lru, dst);
nr_taken++;
}
}
- list_splice(&pc_list, src);
- spin_unlock(&mz->lru_lock);
-
*scanned = scan;
return nr_taken;
}
struct page_cgroup *pc,
enum charge_type ctype)
{
- struct mem_cgroup_per_zone *mz;
- unsigned long flags;
-
/* try_charge() can return NULL to *memcg, taking care of it. */
if (!mem)
return;
return;
}
pc->mem_cgroup = mem;
- /*
- * If a page is accounted as a page cache, insert to inactive list.
- * If anon, insert to active list.
- */
+ smp_wmb();
pc->flags = pcg_default_flags[ctype];
- mz = page_cgroup_zoneinfo(pc);
+ mem_cgroup_charge_statistics(mem, pc, true);
- spin_lock_irqsave(&mz->lru_lock, flags);
- __mem_cgroup_add_list(mz, pc, true);
- spin_unlock_irqrestore(&mz->lru_lock, flags);
unlock_page_cgroup(pc);
}
* @to: mem_cgroup which the page is moved to. @from != @to.
*
* The caller must confirm following.
- * 1. disable irq.
- * 2. lru_lock of old mem_cgroup(@from) should be held.
+ * - page is not on LRU (isolate_page() is useful.)
*
* returns 0 at success,
* returns -EBUSY when lock is busy or "pc" is unstable.
int nid, zid;
int ret = -EBUSY;
- VM_BUG_ON(!irqs_disabled());
VM_BUG_ON(from == to);
+ VM_BUG_ON(PageLRU(pc->page));
nid = page_cgroup_nid(pc);
zid = page_cgroup_zid(pc);
from_mz = mem_cgroup_zoneinfo(from, nid, zid);
to_mz = mem_cgroup_zoneinfo(to, nid, zid);
-
if (!trylock_page_cgroup(pc))
return ret;
if (pc->mem_cgroup != from)
goto out;
- if (spin_trylock(&to_mz->lru_lock)) {
- __mem_cgroup_remove_list(from_mz, pc);
- css_put(&from->css);
- res_counter_uncharge(&from->res, PAGE_SIZE);
- if (do_swap_account)
- res_counter_uncharge(&from->memsw, PAGE_SIZE);
- pc->mem_cgroup = to;
- css_get(&to->css);
- __mem_cgroup_add_list(to_mz, pc, false);
- ret = 0;
- spin_unlock(&to_mz->lru_lock);
- }
+ css_put(&from->css);
+ res_counter_uncharge(&from->res, PAGE_SIZE);
+ mem_cgroup_charge_statistics(from, pc, false);
+ if (do_swap_account)
+ res_counter_uncharge(&from->memsw, PAGE_SIZE);
+ pc->mem_cgroup = to;
+ mem_cgroup_charge_statistics(to, pc, true);
+ css_get(&to->css);
+ ret = 0;
out:
unlock_page_cgroup(pc);
return ret;
struct mem_cgroup *child,
gfp_t gfp_mask)
{
+ struct page *page = pc->page;
struct cgroup *cg = child->css.cgroup;
struct cgroup *pcg = cg->parent;
struct mem_cgroup *parent;
- struct mem_cgroup_per_zone *mz;
- unsigned long flags;
int ret;
/* Is ROOT ? */
if (!pcg)
return -EINVAL;
+
parent = mem_cgroup_from_cont(pcg);
+
ret = __mem_cgroup_try_charge(NULL, gfp_mask, &parent, false);
if (ret)
return ret;
- mz = mem_cgroup_zoneinfo(child,
- page_cgroup_nid(pc), page_cgroup_zid(pc));
+ if (!get_page_unless_zero(page))
+ return -EBUSY;
+
+ ret = isolate_lru_page(page);
+
+ if (ret)
+ goto cancel;
- spin_lock_irqsave(&mz->lru_lock, flags);
ret = mem_cgroup_move_account(pc, child, parent);
- spin_unlock_irqrestore(&mz->lru_lock, flags);
- /* drop extra refcnt */
+ /* drop extra refcnt by try_charge() (move_account increment one) */
css_put(&parent->css);
- /* uncharge if move fails */
- if (ret) {
- res_counter_uncharge(&parent->res, PAGE_SIZE);
- if (do_swap_account)
- res_counter_uncharge(&parent->memsw, PAGE_SIZE);
+ putback_lru_page(page);
+ if (!ret) {
+ put_page(page);
+ return 0;
}
-
+ /* uncharge if move fails */
+cancel:
+ res_counter_uncharge(&parent->res, PAGE_SIZE);
+ if (do_swap_account)
+ res_counter_uncharge(&parent->memsw, PAGE_SIZE);
+ put_page(page);
return ret;
}
}
if (!locked)
unlock_page(page);
+ /* add this page(page_cgroup) to the LRU we want. */
+ mem_cgroup_lru_fixup(page);
return ret;
}
}
}
+ /* add this page(page_cgroup) to the LRU we want. */
+ mem_cgroup_lru_fixup(page);
}
void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
struct page_cgroup *pc;
struct mem_cgroup *mem = NULL;
struct mem_cgroup_per_zone *mz;
- unsigned long flags;
if (mem_cgroup_subsys.disabled)
return NULL;
if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT))
res_counter_uncharge(&mem->memsw, PAGE_SIZE);
+ mem_cgroup_charge_statistics(mem, pc, false);
ClearPageCgroupUsed(pc);
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);
unlock_page_cgroup(pc);
css_put(&mem->css);
return ret;
}
-
/*
* This routine traverse page_cgroup in given list and drop them all.
* *And* this routine doesn't reclaim page itself, just removes page_cgroup.
*/
static int mem_cgroup_force_empty_list(struct mem_cgroup *mem,
- struct mem_cgroup_per_zone *mz,
- enum lru_list lru)
+ int node, int zid, enum lru_list lru)
{
+ struct zone *zone;
+ struct mem_cgroup_per_zone *mz;
struct page_cgroup *pc, *busy;
- unsigned long flags;
- unsigned long loop;
+ unsigned long flags, loop;
struct list_head *list;
int ret = 0;
+ zone = &NODE_DATA(node)->node_zones[zid];
+ mz = mem_cgroup_zoneinfo(mem, node, zid);
list = &mz->lists[lru];
loop = MEM_CGROUP_ZSTAT(mz, lru);
busy = NULL;
while (loop--) {
ret = 0;
- spin_lock_irqsave(&mz->lru_lock, flags);
+ spin_lock_irqsave(&zone->lru_lock, flags);
if (list_empty(list)) {
- spin_unlock_irqrestore(&mz->lru_lock, flags);
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
break;
}
pc = list_entry(list->prev, struct page_cgroup, lru);
if (busy == pc) {
list_move(&pc->lru, list);
busy = 0;
- spin_unlock_irqrestore(&mz->lru_lock, flags);
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
continue;
}
- spin_unlock_irqrestore(&mz->lru_lock, flags);
+ spin_unlock_irqrestore(&zone->lru_lock, flags);
ret = mem_cgroup_move_parent(pc, mem, GFP_HIGHUSER_MOVABLE);
if (ret == -ENOMEM)
} else
busy = NULL;
}
+
if (!ret && !list_empty(list))
return -EBUSY;
return ret;
ret = 0;
for_each_node_state(node, N_POSSIBLE) {
for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) {
- struct mem_cgroup_per_zone *mz;
enum lru_list l;
- mz = mem_cgroup_zoneinfo(mem, node, zid);
for_each_lru(l) {
ret = mem_cgroup_force_empty_list(mem,
- mz, l);
+ node, zid, l);
if (ret)
break;
}
}
}
+ lru_add_drain();
/* try move_account...there may be some *locked* pages. */
if (mem->res.usage)
goto move_account;
for (zone = 0; zone < MAX_NR_ZONES; zone++) {
mz = &pn->zoneinfo[zone];
- spin_lock_init(&mz->lru_lock);
for_each_lru(l)
INIT_LIST_HEAD(&mz->lists[l]);
}
static void mem_cgroup_free(struct mem_cgroup *mem)
{
+ int node;
+
if (atomic_read(&mem->refcnt) > 0)
return;
+
+
+ for_each_node_state(node, N_POSSIBLE)
+ free_mem_cgroup_per_zone_info(mem, node);
+
if (mem_cgroup_size() < PAGE_SIZE)
kfree(mem);
else
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);
-
mem_cgroup_free(mem_cgroup_from_cont(cont));
}
projects / linux-beck.git / commitdiff