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-rw-r--r--Documentation/controllers/memory.txt29
-rw-r--r--include/linux/memcontrol.h11
-rw-r--r--include/linux/swap.h14
-rw-r--r--mm/memcontrol.c400
-rw-r--r--mm/memory.c18
-rw-r--r--mm/swap_state.c5
-rw-r--r--mm/swapfile.c11
-rw-r--r--mm/vmscan.c6
8 files changed, 440 insertions, 54 deletions
diff --git a/Documentation/controllers/memory.txt b/Documentation/controllers/memory.txt
index 9fe2d0e..05fe29a 100644
--- a/Documentation/controllers/memory.txt
+++ b/Documentation/controllers/memory.txt
@@ -137,12 +137,32 @@ behind this approach is that a cgroup that aggressively uses a shared
page will eventually get charged for it (once it is uncharged from
the cgroup that brought it in -- this will happen on memory pressure).
-Exception: When you do swapoff and make swapped-out pages of shmem(tmpfs) to
+Exception: If CONFIG_CGROUP_CGROUP_MEM_RES_CTLR_SWAP is not used..
+When you do swapoff and make swapped-out pages of shmem(tmpfs) to
be backed into memory in force, charges for pages are accounted against the
caller of swapoff rather than the users of shmem.
-2.4 Reclaim
+2.4 Swap Extension (CONFIG_CGROUP_MEM_RES_CTLR_SWAP)
+Swap Extension allows you to record charge for swap. A swapped-in page is
+charged back to original page allocator if possible.
+
+When swap is accounted, following files are added.
+ - memory.memsw.usage_in_bytes.
+ - memory.memsw.limit_in_bytes.
+
+usage of mem+swap is limited by memsw.limit_in_bytes.
+
+Note: why 'mem+swap' rather than swap.
+The global LRU(kswapd) can swap out arbitrary pages. Swap-out means
+to move account from memory to swap...there is no change in usage of
+mem+swap.
+
+In other words, when we want to limit the usage of swap without affecting
+global LRU, mem+swap limit is better than just limiting swap from OS point
+of view.
+
+2.5 Reclaim
Each cgroup maintains a per cgroup LRU that consists of an active
and inactive list. When a cgroup goes over its limit, we first try
@@ -246,6 +266,11 @@ Such charges are freed(at default) or moved to its parent. When moved,
both of RSS and CACHES are moved to parent.
If both of them are busy, rmdir() returns -EBUSY. See 5.1 Also.
+Charges recorded in swap information is not updated at removal of cgroup.
+Recorded information is discarded and a cgroup which uses swap (swapcache)
+will be charged as a new owner of it.
+
+
5. Misc. interfaces.
5.1 force_empty
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 41b46cc..ca51ac7 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -32,6 +32,8 @@ extern int mem_cgroup_newpage_charge(struct page *page, struct mm_struct *mm,
/* for swap handling */
extern int mem_cgroup_try_charge(struct mm_struct *mm,
gfp_t gfp_mask, struct mem_cgroup **ptr);
+extern int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
+ struct page *page, gfp_t mask, struct mem_cgroup **ptr);
extern void mem_cgroup_commit_charge_swapin(struct page *page,
struct mem_cgroup *ptr);
extern void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *ptr);
@@ -80,7 +82,6 @@ extern long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
extern int do_swap_account;
#endif
-
#else /* CONFIG_CGROUP_MEM_RES_CTLR */
struct mem_cgroup;
@@ -97,7 +98,13 @@ static inline int mem_cgroup_cache_charge(struct page *page,
}
static inline int mem_cgroup_try_charge(struct mm_struct *mm,
- gfp_t gfp_mask, struct mem_cgroup **ptr)
+ gfp_t gfp_mask, struct mem_cgroup **ptr)
+{
+ return 0;
+}
+
+static inline int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
+ struct page *page, gfp_t gfp_mask, struct mem_cgroup **ptr)
{
return 0;
}
diff --git a/include/linux/swap.h b/include/linux/swap.h
index f8f3907..be938ce 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -214,7 +214,7 @@ static inline void lru_cache_add_active_file(struct page *page)
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask);
extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem,
- gfp_t gfp_mask);
+ gfp_t gfp_mask, bool noswap);
extern int __isolate_lru_page(struct page *page, int mode, int file);
extern unsigned long shrink_all_memory(unsigned long nr_pages);
extern int vm_swappiness;
@@ -336,7 +336,7 @@ static inline void disable_swap_token(void)
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
extern int mem_cgroup_cache_charge_swapin(struct page *page,
struct mm_struct *mm, gfp_t mask, bool locked);
-extern void mem_cgroup_uncharge_swapcache(struct page *page);
+extern void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent);
#else
static inline
int mem_cgroup_cache_charge_swapin(struct page *page,
@@ -344,7 +344,15 @@ int mem_cgroup_cache_charge_swapin(struct page *page,
{
return 0;
}
-static inline void mem_cgroup_uncharge_swapcache(struct page *page)
+static inline void
+mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
+{
+}
+#endif
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
+extern void mem_cgroup_uncharge_swap(swp_entry_t ent);
+#else
+static inline void mem_cgroup_uncharge_swap(swp_entry_t ent)
{
}
#endif
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 59dd8c1..2efcf38 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -27,6 +27,7 @@
#include <linux/backing-dev.h>
#include <linux/bit_spinlock.h>
#include <linux/rcupdate.h>
+#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/spinlock.h>
@@ -132,12 +133,18 @@ struct mem_cgroup {
*/
struct res_counter res;
/*
+ * the counter to account for mem+swap usage.
+ */
+ struct res_counter memsw;
+ /*
* Per cgroup active and inactive list, similar to the
* per zone LRU lists.
*/
struct mem_cgroup_lru_info info;
int prev_priority; /* for recording reclaim priority */
+ int obsolete;
+ atomic_t refcnt;
/*
* statistics. This must be placed at the end of memcg.
*/
@@ -167,6 +174,17 @@ pcg_default_flags[NR_CHARGE_TYPE] = {
0, /* FORCE */
};
+
+/* for encoding cft->private value on file */
+#define _MEM (0)
+#define _MEMSWAP (1)
+#define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
+#define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
+#define MEMFILE_ATTR(val) ((val) & 0xffff)
+
+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()
*/
@@ -485,7 +503,8 @@ unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
* oom-killer can be invoked.
*/
static int __mem_cgroup_try_charge(struct mm_struct *mm,
- gfp_t gfp_mask, struct mem_cgroup **memcg, bool oom)
+ gfp_t gfp_mask, struct mem_cgroup **memcg,
+ bool oom)
{
struct mem_cgroup *mem;
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
@@ -513,12 +532,25 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
css_get(&mem->css);
}
+ while (1) {
+ int ret;
+ bool noswap = false;
- while (unlikely(res_counter_charge(&mem->res, PAGE_SIZE))) {
+ ret = res_counter_charge(&mem->res, PAGE_SIZE);
+ if (likely(!ret)) {
+ if (!do_swap_account)
+ break;
+ ret = res_counter_charge(&mem->memsw, PAGE_SIZE);
+ if (likely(!ret))
+ break;
+ /* mem+swap counter fails */
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
+ noswap = true;
+ }
if (!(gfp_mask & __GFP_WAIT))
goto nomem;
- if (try_to_free_mem_cgroup_pages(mem, gfp_mask))
+ if (try_to_free_mem_cgroup_pages(mem, gfp_mask, noswap))
continue;
/*
@@ -527,8 +559,13 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
* 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))
+ if (!do_swap_account &&
+ res_counter_check_under_limit(&mem->res))
+ continue;
+ if (do_swap_account &&
+ res_counter_check_under_limit(&mem->memsw))
continue;
if (!nr_retries--) {
@@ -582,6 +619,8 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
if (unlikely(PageCgroupUsed(pc))) {
unlock_page_cgroup(pc);
res_counter_uncharge(&mem->res, PAGE_SIZE);
+ if (do_swap_account)
+ res_counter_uncharge(&mem->memsw, PAGE_SIZE);
css_put(&mem->css);
return;
}
@@ -646,6 +685,8 @@ static int mem_cgroup_move_account(struct page_cgroup *pc,
__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);
@@ -692,8 +733,11 @@ static int mem_cgroup_move_parent(struct page_cgroup *pc,
/* drop extra refcnt */
css_put(&parent->css);
/* uncharge if move fails */
- if (ret)
+ if (ret) {
res_counter_uncharge(&parent->res, PAGE_SIZE);
+ if (do_swap_account)
+ res_counter_uncharge(&parent->memsw, PAGE_SIZE);
+ }
return ret;
}
@@ -791,7 +835,42 @@ int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm,
MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL);
}
+int mem_cgroup_try_charge_swapin(struct mm_struct *mm,
+ struct page *page,
+ gfp_t mask, struct mem_cgroup **ptr)
+{
+ struct mem_cgroup *mem;
+ swp_entry_t ent;
+
+ if (mem_cgroup_subsys.disabled)
+ return 0;
+
+ if (!do_swap_account)
+ goto charge_cur_mm;
+
+ /*
+ * A racing thread's fault, or swapoff, may have already updated
+ * the pte, and even removed page from swap cache: return success
+ * to go on to do_swap_page()'s pte_same() test, which should fail.
+ */
+ if (!PageSwapCache(page))
+ return 0;
+
+ ent.val = page_private(page);
+
+ mem = lookup_swap_cgroup(ent);
+ if (!mem || mem->obsolete)
+ goto charge_cur_mm;
+ *ptr = mem;
+ return __mem_cgroup_try_charge(NULL, mask, ptr, true);
+charge_cur_mm:
+ if (unlikely(!mm))
+ mm = &init_mm;
+ return __mem_cgroup_try_charge(mm, mask, ptr, true);
+}
+
#ifdef CONFIG_SWAP
+
int mem_cgroup_cache_charge_swapin(struct page *page,
struct mm_struct *mm, gfp_t mask, bool locked)
{
@@ -808,8 +887,28 @@ int mem_cgroup_cache_charge_swapin(struct page *page,
* we reach here.
*/
if (PageSwapCache(page)) {
+ struct mem_cgroup *mem = NULL;
+ swp_entry_t ent;
+
+ ent.val = page_private(page);
+ if (do_swap_account) {
+ mem = lookup_swap_cgroup(ent);
+ if (mem && mem->obsolete)
+ mem = NULL;
+ if (mem)
+ mm = NULL;
+ }
ret = mem_cgroup_charge_common(page, mm, mask,
- MEM_CGROUP_CHARGE_TYPE_SHMEM, NULL);
+ MEM_CGROUP_CHARGE_TYPE_SHMEM, mem);
+
+ if (!ret && do_swap_account) {
+ /* avoid double counting */
+ mem = swap_cgroup_record(ent, NULL);
+ if (mem) {
+ res_counter_uncharge(&mem->memsw, PAGE_SIZE);
+ mem_cgroup_put(mem);
+ }
+ }
}
if (!locked)
unlock_page(page);
@@ -828,6 +927,23 @@ void mem_cgroup_commit_charge_swapin(struct page *page, struct mem_cgroup *ptr)
return;
pc = lookup_page_cgroup(page);
__mem_cgroup_commit_charge(ptr, pc, MEM_CGROUP_CHARGE_TYPE_MAPPED);
+ /*
+ * Now swap is on-memory. This means this page may be
+ * counted both as mem and swap....double count.
+ * Fix it by uncharging from memsw. This SwapCache is stable
+ * because we're still under lock_page().
+ */
+ if (do_swap_account) {
+ swp_entry_t ent = {.val = page_private(page)};
+ struct mem_cgroup *memcg;
+ memcg = swap_cgroup_record(ent, NULL);
+ if (memcg) {
+ /* If memcg is obsolete, memcg can be != ptr */
+ res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
+ mem_cgroup_put(memcg);
+ }
+
+ }
}
void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
@@ -837,6 +953,8 @@ void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
if (!mem)
return;
res_counter_uncharge(&mem->res, PAGE_SIZE);
+ if (do_swap_account)
+ res_counter_uncharge(&mem->memsw, PAGE_SIZE);
css_put(&mem->css);
}
@@ -844,29 +962,31 @@ void mem_cgroup_cancel_charge_swapin(struct mem_cgroup *mem)
/*
* uncharge if !page_mapped(page)
*/
-static void
+static struct mem_cgroup *
__mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
{
struct page_cgroup *pc;
- struct mem_cgroup *mem;
+ struct mem_cgroup *mem = NULL;
struct mem_cgroup_per_zone *mz;
unsigned long flags;
if (mem_cgroup_subsys.disabled)
- return;
+ return NULL;
if (PageSwapCache(page))
- return;
+ return NULL;
/*
* Check if our page_cgroup is valid
*/
pc = lookup_page_cgroup(page);
if (unlikely(!pc || !PageCgroupUsed(pc)))
- return;
+ return NULL;
lock_page_cgroup(pc);
+ mem = pc->mem_cgroup;
+
if (!PageCgroupUsed(pc))
goto unlock_out;
@@ -886,8 +1006,11 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
break;
}
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
+ if (do_swap_account && (ctype != MEM_CGROUP_CHARGE_TYPE_SWAPOUT))
+ res_counter_uncharge(&mem->memsw, PAGE_SIZE);
+
ClearPageCgroupUsed(pc);
- mem = pc->mem_cgroup;
mz = page_cgroup_zoneinfo(pc);
spin_lock_irqsave(&mz->lru_lock, flags);
@@ -895,14 +1018,13 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
spin_unlock_irqrestore(&mz->lru_lock, flags);
unlock_page_cgroup(pc);
- res_counter_uncharge(&mem->res, PAGE_SIZE);
css_put(&mem->css);
- return;
+ return mem;
unlock_out:
unlock_page_cgroup(pc);
- return;
+ return NULL;
}
void mem_cgroup_uncharge_page(struct page *page)
@@ -922,10 +1044,42 @@ void mem_cgroup_uncharge_cache_page(struct page *page)
__mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_CACHE);
}
-void mem_cgroup_uncharge_swapcache(struct page *page)
+/*
+ * called from __delete_from_swap_cache() and drop "page" account.
+ * memcg information is recorded to swap_cgroup of "ent"
+ */
+void mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
+{
+ struct mem_cgroup *memcg;
+
+ memcg = __mem_cgroup_uncharge_common(page,
+ MEM_CGROUP_CHARGE_TYPE_SWAPOUT);
+ /* record memcg information */
+ if (do_swap_account && memcg) {
+ swap_cgroup_record(ent, memcg);
+ mem_cgroup_get(memcg);
+ }
+}
+
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
+/*
+ * called from swap_entry_free(). remove record in swap_cgroup and
+ * uncharge "memsw" account.
+ */
+void mem_cgroup_uncharge_swap(swp_entry_t ent)
{
- __mem_cgroup_uncharge_common(page, MEM_CGROUP_CHARGE_TYPE_SWAPOUT);
+ struct mem_cgroup *memcg;
+
+ if (!do_swap_account)
+ return;
+
+ memcg = swap_cgroup_record(ent, NULL);
+ if (memcg) {
+ res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
+ mem_cgroup_put(memcg);
+ }
}
+#endif
/*
* Before starting migration, account PAGE_SIZE to mem_cgroup that the old
@@ -1034,7 +1188,7 @@ int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask)
rcu_read_unlock();
do {
- progress = try_to_free_mem_cgroup_pages(mem, gfp_mask);
+ progress = try_to_free_mem_cgroup_pages(mem, gfp_mask, true);
progress += res_counter_check_under_limit(&mem->res);
} while (!progress && --retry);
@@ -1044,26 +1198,84 @@ int mem_cgroup_shrink_usage(struct mm_struct *mm, gfp_t gfp_mask)
return 0;
}
+static DEFINE_MUTEX(set_limit_mutex);
+
static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
- unsigned long long val)
+ unsigned long long val)
{
int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
int progress;
+ u64 memswlimit;
int ret = 0;
- while (res_counter_set_limit(&memcg->res, val)) {
+ while (retry_count) {
if (signal_pending(current)) {
ret = -EINTR;
break;
}
- if (!retry_count) {
- ret = -EBUSY;
+ /*
+ * Rather than hide all in some function, I do this in
+ * open coded manner. You see what this really does.
+ * We have to guarantee mem->res.limit < mem->memsw.limit.
+ */
+ mutex_lock(&set_limit_mutex);
+ memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
+ if (memswlimit < val) {
+ ret = -EINVAL;
+ mutex_unlock(&set_limit_mutex);
break;
}
+ ret = res_counter_set_limit(&memcg->res, val);
+ mutex_unlock(&set_limit_mutex);
+
+ if (!ret)
+ break;
+
progress = try_to_free_mem_cgroup_pages(memcg,
- GFP_HIGHUSER_MOVABLE);
- if (!progress)
+ GFP_HIGHUSER_MOVABLE, false);
+ if (!progress) retry_count--;
+ }
+ return ret;
+}
+
+int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
+ unsigned long long val)
+{
+ int retry_count = MEM_CGROUP_RECLAIM_RETRIES;
+ u64 memlimit, oldusage, curusage;
+ int ret;
+
+ if (!do_swap_account)
+ return -EINVAL;
+
+ while (retry_count) {
+ 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 mem->res.limit < mem->memsw.limit.
+ */
+ mutex_lock(&set_limit_mutex);
+ memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT);
+ if (memlimit > val) {
+ ret = -EINVAL;
+ mutex_unlock(&set_limit_mutex);
+ break;
+ }
+ ret = res_counter_set_limit(&memcg->memsw, val);
+ mutex_unlock(&set_limit_mutex);
+
+ if (!ret)
+ break;
+
+ oldusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
+ try_to_free_mem_cgroup_pages(memcg, GFP_HIGHUSER_MOVABLE, true);
+ curusage = res_counter_read_u64(&memcg->memsw, RES_USAGE);
+ if (curusage >= oldusage)
retry_count--;
}
return ret;
@@ -1193,7 +1405,7 @@ try_to_free:
goto out;
}
progress = try_to_free_mem_cgroup_pages(mem,
- GFP_HIGHUSER_MOVABLE);
+ GFP_HIGHUSER_MOVABLE, false);
if (!progress) {
nr_retries--;
/* maybe some writeback is necessary */
@@ -1216,8 +1428,25 @@ int mem_cgroup_force_empty_write(struct cgroup *cont, unsigned int event)
static u64 mem_cgroup_read(struct cgroup *cont, struct cftype *cft)
{
- return res_counter_read_u64(&mem_cgroup_from_cont(cont)->res,
- cft->private);
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
+ u64 val = 0;
+ int type, name;
+
+ type = MEMFILE_TYPE(cft->private);
+ name = MEMFILE_ATTR(cft->private);
+ switch (type) {
+ case _MEM:
+ val = res_counter_read_u64(&mem->res, name);
+ break;
+ case _MEMSWAP:
+ if (do_swap_account)
+ val = res_counter_read_u64(&mem->memsw, name);
+ break;
+ default:
+ BUG();
+ break;
+ }
+ return val;
}
/*
* The user of this function is...
@@ -1227,15 +1456,22 @@ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
const char *buffer)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
+ int type, name;
unsigned long long val;
int ret;
- switch (cft->private) {
+ type = MEMFILE_TYPE(cft->private);
+ name = MEMFILE_ATTR(cft->private);
+ switch (name) {
case RES_LIMIT:
/* This function does all necessary parse...reuse it */
ret = res_counter_memparse_write_strategy(buffer, &val);
- if (!ret)
+ if (ret)
+ break;
+ if (type == _MEM)
ret = mem_cgroup_resize_limit(memcg, val);
+ else
+ ret = mem_cgroup_resize_memsw_limit(memcg, val);
break;
default:
ret = -EINVAL; /* should be BUG() ? */
@@ -1247,14 +1483,23 @@ static int mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
static int mem_cgroup_reset(struct cgroup *cont, unsigned int event)
{
struct mem_cgroup *mem;
+ int type, name;
mem = mem_cgroup_from_cont(cont);
- switch (event) {
+ type = MEMFILE_TYPE(event);
+ name = MEMFILE_ATTR(event);
+ switch (name) {
case RES_MAX_USAGE:
- res_counter_reset_max(&mem->res);
+ if (type == _MEM)
+ res_counter_reset_max(&mem->res);
+ else
+ res_counter_reset_max(&mem->memsw);
break;
case RES_FAILCNT:
- res_counter_reset_failcnt(&mem->res);
+ if (type == _MEM)
+ res_counter_reset_failcnt(&mem->res);
+ else
+ res_counter_reset_failcnt(&mem->memsw);
break;
}
return 0;
@@ -1315,24 +1560,24 @@ static int mem_control_stat_show(struct cgroup *cont, struct cftype *cft,
static struct cftype mem_cgroup_files[] = {
{
.name = "usage_in_bytes",
- .private = RES_USAGE,
+ .private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
.read_u64 = mem_cgroup_read,
},
{
.name = "max_usage_in_bytes",
- .private = RES_MAX_USAGE,
+ .private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
.trigger = mem_cgroup_reset,
.read_u64 = mem_cgroup_read,
},
{
.name = "limit_in_bytes",
- .private = RES_LIMIT,
+ .private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
.write_string = mem_cgroup_write,
.read_u64 = mem_cgroup_read,
},
{
.name = "failcnt",
- .private = RES_FAILCNT,
+ .private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
.trigger = mem_cgroup_reset,
.read_u64 = mem_cgroup_read,
},
@@ -1346,6 +1591,47 @@ static struct cftype mem_cgroup_files[] = {
},
};
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
+static struct cftype memsw_cgroup_files[] = {
+ {
+ .name = "memsw.usage_in_bytes",
+ .private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
+ .read_u64 = mem_cgroup_read,
+ },
+ {
+ .name = "memsw.max_usage_in_bytes",
+ .private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
+ .trigger = mem_cgroup_reset,
+ .read_u64 = mem_cgroup_read,
+ },
+ {
+ .name = "memsw.limit_in_bytes",
+ .private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
+ .write_string = mem_cgroup_write,
+ .read_u64 = mem_cgroup_read,
+ },
+ {
+ .name = "memsw.failcnt",
+ .private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
+ .trigger = mem_cgroup_reset,
+ .read_u64 = mem_cgroup_read,
+ },
+};
+
+static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
+{
+ if (!do_swap_account)
+ return 0;
+ return cgroup_add_files(cont, ss, memsw_cgroup_files,
+ ARRAY_SIZE(memsw_cgroup_files));
+};
+#else
+static int register_memsw_files(struct cgroup *cont, struct cgroup_subsys *ss)
+{
+ return 0;
+}
+#endif
+
static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node)
{
struct mem_cgroup_per_node *pn;
@@ -1404,14 +1690,44 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
return mem;
}
+/*
+ * At destroying mem_cgroup, references from swap_cgroup can remain.
+ * (scanning all at force_empty is too costly...)
+ *
+ * Instead of clearing all references at force_empty, we remember
+ * the number of reference from swap_cgroup and free mem_cgroup when
+ * it goes down to 0.
+ *
+ * When mem_cgroup is destroyed, mem->obsolete will be set to 0 and
+ * entry which points to this memcg will be ignore at swapin.
+ *
+ * Removal of cgroup itself succeeds regardless of refs from swap.
+ */
+
static void mem_cgroup_free(struct mem_cgroup *mem)
{
+ if (atomic_read(&mem->refcnt) > 0)
+ return;
if (mem_cgroup_size() < PAGE_SIZE)
kfree(mem);
else
vfree(mem);
}
+static void mem_cgroup_get(struct mem_cgroup *mem)
+{
+ atomic_inc(&mem->refcnt);
+}
+
+static void mem_cgroup_put(struct mem_cgroup *mem)
+{
+ if (atomic_dec_and_test(&mem->refcnt)) {
+ if (!mem->obsolete)
+ return;
+ mem_cgroup_free(mem);
+ }
+}
+
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
static void __init enable_swap_cgroup(void)
@@ -1436,6 +1752,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
return ERR_PTR(-ENOMEM);
res_counter_init(&mem->res);
+ res_counter_init(&mem->memsw);
for_each_node_state(node, N_POSSIBLE)
if (alloc_mem_cgroup_per_zone_info(mem, node))
@@ -1456,6 +1773,7 @@ static void mem_cgroup_pre_destroy(struct cgroup_subsys *ss,
struct cgroup *cont)
{
struct mem_cgroup *mem = mem_cgroup_from_cont(cont);
+ mem->obsolete = 1;
mem_cgroup_force_empty(mem, false);
}
@@ -1474,8 +1792,14 @@ static void mem_cgroup_destroy(struct cgroup_subsys *ss,
static int mem_cgroup_populate(struct cgroup_subsys *ss,
struct cgroup *cont)
{
- return cgroup_add_files(cont, ss, mem_cgroup_files,
- ARRAY_SIZE(mem_cgroup_files));
+ int ret;
+
+ ret = cgroup_add_files(cont, ss, mem_cgroup_files,
+ ARRAY_SIZE(mem_cgroup_files));
+
+ if (!ret)
+ ret = register_memsw_files(cont, ss);
+ return ret;
}
static void mem_cgroup_move_task(struct cgroup_subsys *ss,
diff --git a/mm/memory.c b/mm/memory.c
index ba5189e..1358012 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2431,7 +2431,8 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
lock_page(page);
delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
- if (mem_cgroup_try_charge(mm, GFP_HIGHUSER_MOVABLE, &ptr) == -ENOMEM) {
+ if (mem_cgroup_try_charge_swapin(mm, page,
+ GFP_HIGHUSER_MOVABLE, &ptr) == -ENOMEM) {
ret = VM_FAULT_OOM;
unlock_page(page);
goto out;
@@ -2449,8 +2450,20 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
goto out_nomap;
}
- /* The page isn't present yet, go ahead with the fault. */
+ /*
+ * The page isn't present yet, go ahead with the fault.
+ *
+ * Be careful about the sequence of operations here.
+ * To get its accounting right, reuse_swap_page() must be called
+ * while the page is counted on swap but not yet in mapcount i.e.
+ * before page_add_anon_rmap() and swap_free(); try_to_free_swap()
+ * must be called after the swap_free(), or it will never succeed.
+ * And mem_cgroup_commit_charge_swapin(), which uses the swp_entry
+ * in page->private, must be called before reuse_swap_page(),
+ * which may delete_from_swap_cache().
+ */
+ mem_cgroup_commit_charge_swapin(page, ptr);
inc_mm_counter(mm, anon_rss);
pte = mk_pte(page, vma->vm_page_prot);
if (write_access && reuse_swap_page(page)) {
@@ -2461,7 +2474,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
flush_icache_page(vma, page);
set_pte_at(mm, address, page_table, pte);
page_add_anon_rmap(page, vma, address);
- mem_cgroup_commit_charge_swapin(page, ptr);
swap_free(entry);
if (vm_swap_full() || (vma->vm_flags & VM_LOCKED) || PageMlocked(page))
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 09291ca..3ecea98 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -17,6 +17,7 @@
#include <linux/backing-dev.h>
#include <linux/pagevec.h>
#include <linux/migrate.h>
+#include <linux/page_cgroup.h>
#include <asm/pgtable.h>
@@ -108,6 +109,8 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask)
*/
void __delete_from_swap_cache(struct page *page)
{
+ swp_entry_t ent = {.val = page_private(page)};
+
VM_BUG_ON(!PageLocked(page));
VM_BUG_ON(!PageSwapCache(page));
VM_BUG_ON(PageWriteback(page));
@@ -118,7 +121,7 @@ void __delete_from_swap_cache(struct page *page)
total_swapcache_pages--;
__dec_zone_page_state(page, NR_FILE_PAGES);
INC_CACHE_INFO(del_total);
- mem_cgroup_uncharge_swapcache(page);
+ mem_cgroup_uncharge_swapcache(page, ent);
}
/**
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 1e7a715..0579d90 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -471,8 +471,9 @@ out:
return NULL;
}
-static int swap_entry_free(struct swap_info_struct *p, unsigned long offset)
+static int swap_entry_free(struct swap_info_struct *p, swp_entry_t ent)
{
+ unsigned long offset = swp_offset(ent);
int count = p->swap_map[offset];
if (count < SWAP_MAP_MAX) {
@@ -487,6 +488,7 @@ static int swap_entry_free(struct swap_info_struct *p, unsigned long offset)
swap_list.next = p - swap_info;
nr_swap_pages++;
p->inuse_pages--;
+ mem_cgroup_uncharge_swap(ent);
}
}
return count;
@@ -502,7 +504,7 @@ void swap_free(swp_entry_t entry)
p = swap_info_get(entry);
if (p) {
- swap_entry_free(p, swp_offset(entry));
+ swap_entry_free(p, entry);
spin_unlock(&swap_lock);
}
}
@@ -582,7 +584,7 @@ int free_swap_and_cache(swp_entry_t entry)
p = swap_info_get(entry);
if (p) {
- if (swap_entry_free(p, swp_offset(entry)) == 1) {
+ if (swap_entry_free(p, entry) == 1) {
page = find_get_page(&swapper_space, entry.val);
if (page && !trylock_page(page)) {
page_cache_release(page);
@@ -696,7 +698,8 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
pte_t *pte;
int ret = 1;
- if (mem_cgroup_try_charge(vma->vm_mm, GFP_HIGHUSER_MOVABLE, &ptr))
+ if (mem_cgroup_try_charge_swapin(vma->vm_mm, page,
+ GFP_HIGHUSER_MOVABLE, &ptr))
ret = -ENOMEM;
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b07c48b..f63b20d 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1661,7 +1661,8 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
- gfp_t gfp_mask)
+ gfp_t gfp_mask,
+ bool noswap)
{
struct scan_control sc = {
.may_writepage = !laptop_mode,
@@ -1674,6 +1675,9 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
};
struct zonelist *zonelist;
+ if (noswap)
+ sc.may_swap = 0;
+
sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
zonelist = NODE_DATA(numa_node_id())->node_zonelists;
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