memcgroup: add the max_usage member on the res_counter
This field is the maximal value of the usage one since the counter creation
(or since the latest reset).
To reset this to the usage value simply write anything to the appropriate
cgroup file.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: 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>
diff --git a/include/linux/res_counter.h b/include/linux/res_counter.h
index 8cb1ecd..df8085a 100644
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -25,6 +25,10 @@
*/
unsigned long long usage;
/*
+ * the maximal value of the usage from the counter creation
+ */
+ unsigned long long max_usage;
+ /*
* the limit that usage cannot exceed
*/
unsigned long long limit;
@@ -67,6 +71,7 @@
enum {
RES_USAGE,
+ RES_MAX_USAGE,
RES_LIMIT,
RES_FAILCNT,
};
@@ -127,4 +132,13 @@
return ret;
}
+static inline void res_counter_reset_max(struct res_counter *cnt)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&cnt->lock, flags);
+ cnt->max_usage = cnt->usage;
+ spin_unlock_irqrestore(&cnt->lock, flags);
+}
+
#endif
diff --git a/kernel/res_counter.c b/kernel/res_counter.c
index 7058765..d3c61b4 100644
--- a/kernel/res_counter.c
+++ b/kernel/res_counter.c
@@ -28,6 +28,8 @@
}
counter->usage += val;
+ if (counter->usage > counter->max_usage)
+ counter->max_usage = counter->usage;
return 0;
}
@@ -66,6 +68,8 @@
switch (member) {
case RES_USAGE:
return &counter->usage;
+ case RES_MAX_USAGE:
+ return &counter->max_usage;
case RES_LIMIT:
return &counter->limit;
case RES_FAILCNT:
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 49d8081..350a14d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -855,6 +855,17 @@
mem_cgroup_write_strategy);
}
+static ssize_t mem_cgroup_max_reset(struct cgroup *cont, struct cftype *cft,
+ struct file *file, const char __user *userbuf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct mem_cgroup *mem;
+
+ mem = mem_cgroup_from_cont(cont);
+ res_counter_reset_max(&mem->res);
+ return nbytes;
+}
+
static ssize_t mem_force_empty_write(struct cgroup *cont,
struct cftype *cft, struct file *file,
const char __user *userbuf,
@@ -910,6 +921,12 @@
.read_u64 = mem_cgroup_read,
},
{
+ .name = "max_usage_in_bytes",
+ .private = RES_MAX_USAGE,
+ .write = mem_cgroup_max_reset,
+ .read_u64 = mem_cgroup_read,
+ },
+ {
.name = "limit_in_bytes",
.private = RES_LIMIT,
.write = mem_cgroup_write,