perf kmem: Make it work again on non NUMA machines

hi all,

Now on non NUMA machines with 3.10 stable,perf kmem command does not work well. For instance, when exec perf kmem record sleep 2, we can get the perf.data file correctly. but when we exec perf kmem stat there is nothing return.
In upstream the bug has been fixed and perf kmem work well on non NUMA machines.

Can we cherry-pick it to stable repo.

The commit id is 4921e320244e099bdf237fd10428594ce5f5b87d,the detail as follows:

commit 4921e320244e099bdf237fd10428594ce5f5b87d

Author: Jiri Olsa <[email protected]>
Date:   Thu Sep 12 18:39:36 2013 +0200

perf kmem: Make it work again on non NUMA machines

The commit '2814eb0 perf kmem: Remove die() calls' disabled 'perf kmem' command for machines without numa support. It made the command fail if '/sys/devices/system/node' dir wasn't found.

Skipping the numa based initialization in case the directory is not found and continue execution.

index c2dff9c..9b5f077 100644
@@ -101,7 +101,7 @@ static int setup_cpunode_map(void)
 
        dir1 = opendir(PATH_SYS_NODE);
        if (!dir1)
-           return -1;
+         return 0;
 
        while ((dent1 = readdir(dir1)) != NULL) {
                if (dent1->d_type != DT_DIR ||