memory cgroup enhancements: add memory.stat file

Show accounted information of memory cgroup by memory.stat file

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix printk warning]
Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 5f3ad9c37bea..904e9a9c223d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -29,6 +29,7 @@
 #include <linux/swap.h>
 #include <linux/spinlock.h>
 #include <linux/fs.h>
+#include <linux/seq_file.h>
 
 #include <asm/uaccess.h>
 
@@ -794,6 +795,49 @@ static ssize_t mem_force_empty_read(struct cgroup *cont,
 }
 
 
+static const struct mem_cgroup_stat_desc {
+        const char *msg;
+        u64 unit;
+} mem_cgroup_stat_desc[] = {
+        [MEM_CGROUP_STAT_CACHE] = { "cache", PAGE_SIZE, },
+        [MEM_CGROUP_STAT_RSS] = { "rss", PAGE_SIZE, },
+};
+
+static int mem_control_stat_show(struct seq_file *m, void *arg)
+{
+        struct cgroup *cont = m->private;
+        struct mem_cgroup *mem_cont = mem_cgroup_from_cont(cont);
+        struct mem_cgroup_stat *stat = &mem_cont->stat;
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(stat->cpustat[0].count); i++) {
+                s64 val;
+
+                val = mem_cgroup_read_stat(stat, i);
+                val *= mem_cgroup_stat_desc[i].unit;
+                seq_printf(m, "%s %lld\n", mem_cgroup_stat_desc[i].msg,
+                                (long long)val);
+        }
+        return 0;
+}
+
+static const struct file_operations mem_control_stat_file_operations = {
+        .read = seq_read,
+        .llseek = seq_lseek,
+        .release = single_release,
+};
+
+static int mem_control_stat_open(struct inode *unused, struct file *file)
+{
+        /* XXX __d_cont */
+        struct cgroup *cont = file->f_dentry->d_parent->d_fsdata;
+
+        file->f_op = &mem_control_stat_file_operations;
+        return single_open(file, mem_control_stat_show, cont);
+}
+
+
+
 static struct cftype mem_cgroup_files[] = {
         {
                 .name = "usage_in_bytes",
@@ -821,6 +865,10 @@ static struct cftype mem_cgroup_files[] = {
                 .write = mem_force_empty_write,
                 .read = mem_force_empty_read,
         },
+        {
+                .name = "stat",
+                .open = mem_control_stat_open,
+        },
 };
 
 static struct mem_cgroup init_mem_cgroup;