Change the interface to use bytes instead of pages. Page sizes can vary
across platforms and configurations. A new strategy routine has been added
to the resource counters infrastructure to format the data as desired.
Suggested by David Rientjes, Andrew Morton and Herbert Poetzl
Tested on a UML setup with the config for memory control enabled.
[kamezawa.hiroyu@jp.fujitsu.com: possible race fix in res_counter]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: Paul Menage <menage@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: David Rientjes <rientjes@google.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since now we're in the 0 cgroup,
We can alter the memory limit:
Since now we're in the 0 cgroup,
We can alter the memory limit:
-# echo -n 6000 > /cgroups/0/memory.limit
+# echo -n 4M > /cgroups/0/memory.limit_in_bytes
+
+NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
+mega or gigabytes.
+
+# cat /cgroups/0/memory.limit_in_bytes
+4194304 Bytes
+
+NOTE: The interface has now changed to display the usage in bytes
+instead of pages
-# cat /cgroups/0/memory.usage
-25
+# cat /cgroups/0/memory.usage_in_bytes
+1216512 Bytes
+
+A successful write to this file does not guarantee a successful set of
+this limit to the value written into the file. This can be due to a
+number of factors, such as rounding up to page boundaries or the total
+availability of memory on the system. The user is required to re-read
+this file after a write to guarantee the value committed by the kernel.
+
+# echo -n 1 > memory.limit_in_bytes
+# cat memory.limit_in_bytes
+4096 Bytes
The memory.failcnt field gives the number of times that the cgroup limit was
exceeded.
The memory.failcnt field gives the number of times that the cgroup limit was
exceeded.
tasks have migrated away from it. If some pages are still left, after following
the steps listed in sections 4.1 and 4.2, check the Swap Cache usage in
/proc/meminfo to see if the Swap Cache usage is showing up in the
tasks have migrated away from it. If some pages are still left, after following
the steps listed in sections 4.1 and 4.2, check the Swap Cache usage in
/proc/meminfo to see if the Swap Cache usage is showing up in the
-cgroups memory.usage counter. A simple test of swapoff -a and swapon -a
-should free any pending Swap Cache usage.
+cgroups memory.usage_in_bytes counter. A simple test of swapoff -a and
+swapon -a should free any pending Swap Cache usage.
4.4 Choosing what to account -- Page Cache (unmapped) vs RSS (mapped)?
4.4 Choosing what to account -- Page Cache (unmapped) vs RSS (mapped)?
/*
* the current resource consumption level
*/
/*
* the current resource consumption level
*/
+ unsigned long long usage;
/*
* the limit that usage cannot exceed
*/
/*
* the limit that usage cannot exceed
*/
+ unsigned long long limit;
/*
* the number of unsuccessful attempts to consume the resource
*/
/*
* the number of unsuccessful attempts to consume the resource
*/
+ unsigned long long failcnt;
/*
* the lock to protect all of the above.
* the routines below consider this to be IRQ-safe
/*
* the lock to protect all of the above.
* the routines below consider this to be IRQ-safe
*/
ssize_t res_counter_read(struct res_counter *counter, int member,
*/
ssize_t res_counter_read(struct res_counter *counter, int member,
- const char __user *buf, size_t nbytes, loff_t *pos);
+ const char __user *buf, size_t nbytes, loff_t *pos,
+ int (*read_strategy)(unsigned long long val, char *s));
ssize_t res_counter_write(struct res_counter *counter, int member,
ssize_t res_counter_write(struct res_counter *counter, int member,
- const char __user *buf, size_t nbytes, loff_t *pos);
+ const char __user *buf, size_t nbytes, loff_t *pos,
+ int (*write_strategy)(char *buf, unsigned long long *val));
/*
* the field descriptors. one for each member of res_counter
/*
* the field descriptors. one for each member of res_counter
void res_counter_init(struct res_counter *counter)
{
spin_lock_init(&counter->lock);
void res_counter_init(struct res_counter *counter)
{
spin_lock_init(&counter->lock);
- counter->limit = (unsigned long)LONG_MAX;
+ counter->limit = (unsigned long long)LLONG_MAX;
}
int res_counter_charge_locked(struct res_counter *counter, unsigned long val)
}
int res_counter_charge_locked(struct res_counter *counter, unsigned long val)
-static inline unsigned long *res_counter_member(struct res_counter *counter,
- int member)
+static inline unsigned long long *
+res_counter_member(struct res_counter *counter, int member)
{
switch (member) {
case RES_USAGE:
{
switch (member) {
case RES_USAGE:
}
ssize_t res_counter_read(struct res_counter *counter, int member,
}
ssize_t res_counter_read(struct res_counter *counter, int member,
- const char __user *userbuf, size_t nbytes, loff_t *pos)
+ const char __user *userbuf, size_t nbytes, loff_t *pos,
+ int (*read_strategy)(unsigned long long val, char *st_buf))
+ unsigned long long *val;
char buf[64], *s;
s = buf;
val = res_counter_member(counter, member);
char buf[64], *s;
s = buf;
val = res_counter_member(counter, member);
- s += sprintf(s, "%lu\n", *val);
+ if (read_strategy)
+ s += read_strategy(*val, s);
+ else
+ s += sprintf(s, "%llu\n", *val);
return simple_read_from_buffer((void __user *)userbuf, nbytes,
pos, buf, s - buf);
}
ssize_t res_counter_write(struct res_counter *counter, int member,
return simple_read_from_buffer((void __user *)userbuf, nbytes,
pos, buf, s - buf);
}
ssize_t res_counter_write(struct res_counter *counter, int member,
- const char __user *userbuf, size_t nbytes, loff_t *pos)
+ const char __user *userbuf, size_t nbytes, loff_t *pos,
+ int (*write_strategy)(char *st_buf, unsigned long long *val))
{
int ret;
char *buf, *end;
{
int ret;
char *buf, *end;
- unsigned long tmp, *val;
+ unsigned long flags;
+ unsigned long long tmp, *val;
buf = kmalloc(nbytes + 1, GFP_KERNEL);
ret = -ENOMEM;
buf = kmalloc(nbytes + 1, GFP_KERNEL);
ret = -ENOMEM;
goto out_free;
ret = -EINVAL;
goto out_free;
ret = -EINVAL;
- tmp = simple_strtoul(buf, &end, 10);
- if (*end != '\0')
- goto out_free;
+ if (write_strategy) {
+ if (write_strategy(buf, &tmp)) {
+ goto out_free;
+ }
+ } else {
+ tmp = simple_strtoull(buf, &end, 10);
+ if (*end != '\0')
+ goto out_free;
+ }
+ spin_lock_irqsave(&counter->lock, flags);
val = res_counter_member(counter, member);
*val = tmp;
val = res_counter_member(counter, member);
*val = tmp;
+ spin_unlock_irqrestore(&counter->lock, flags);
ret = nbytes;
out_free:
kfree(buf);
ret = nbytes;
out_free:
kfree(buf);
* If we created the page_cgroup, we should free it on exceeding
* the cgroup limit.
*/
* If we created the page_cgroup, we should free it on exceeding
* the cgroup limit.
*/
- while (res_counter_charge(&mem->res, 1)) {
+ while (res_counter_charge(&mem->res, PAGE_SIZE)) {
if (try_to_free_mem_cgroup_pages(mem))
continue;
if (try_to_free_mem_cgroup_pages(mem))
continue;
kfree(pc);
pc = race_pc;
atomic_inc(&pc->ref_cnt);
kfree(pc);
pc = race_pc;
atomic_inc(&pc->ref_cnt);
- res_counter_uncharge(&mem->res, 1);
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
css_put(&mem->css);
goto done;
}
css_put(&mem->css);
goto done;
}
css_put(&mem->css);
page_assign_page_cgroup(page, NULL);
unlock_page_cgroup(page);
css_put(&mem->css);
page_assign_page_cgroup(page, NULL);
unlock_page_cgroup(page);
- res_counter_uncharge(&mem->res, 1);
+ res_counter_uncharge(&mem->res, PAGE_SIZE);
spin_lock_irqsave(&mem->lru_lock, flags);
list_del_init(&pc->lru);
spin_lock_irqsave(&mem->lru_lock, flags);
list_del_init(&pc->lru);
-static ssize_t mem_cgroup_read(struct cgroup *cont, struct cftype *cft,
- struct file *file, char __user *userbuf, size_t nbytes,
- loff_t *ppos)
+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 ssize_t mem_cgroup_read(struct cgroup *cont,
+ struct cftype *cft, struct file *file,
+ char __user *userbuf, size_t nbytes, loff_t *ppos)
{
return res_counter_read(&mem_cgroup_from_cont(cont)->res,
{
return res_counter_read(&mem_cgroup_from_cont(cont)->res,
- cft->private, userbuf, nbytes, ppos);
+ cft->private, userbuf, nbytes, ppos,
+ NULL);
}
static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft,
}
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,
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 struct cftype mem_cgroup_files[] = {
{
}
static struct cftype mem_cgroup_files[] = {
{
+ .name = "usage_in_bytes",
.private = RES_USAGE,
.read = mem_cgroup_read,
},
{
.private = RES_USAGE,
.read = mem_cgroup_read,
},
{
+ .name = "limit_in_bytes",
.private = RES_LIMIT,
.write = mem_cgroup_write,
.read = mem_cgroup_read,
.private = RES_LIMIT,
.write = mem_cgroup_write,
.read = mem_cgroup_read,