CGroup API files: add res_counter_read_u64()
Adds a function for returning the value of a resource counter member, in a
form suitable for use in a cgroup read_u64 control file method.
Signed-off-by: Paul Menage <menage@google.com>
Cc: "Li Zefan" <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "YAMAMOTO Takashi" <yamamoto@valinux.co.jp>
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 61363ce..8cb1ecd 100644
--- a/include/linux/res_counter.h
+++ b/include/linux/res_counter.h
@@ -39,8 +39,9 @@
spinlock_t lock;
};
-/*
+/**
* Helpers to interact with userspace
+ * res_counter_read_u64() - returns the value of the specified member.
* res_counter_read/_write - put/get the specified fields from the
* res_counter struct to/from the user
*
@@ -51,6 +52,8 @@
* @pos: and the offset.
*/
+u64 res_counter_read_u64(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,
int (*read_strategy)(unsigned long long val, char *s));