commit 7d1e13505be8c2bd2207894f4e0f069e1f9b51c9
author Pavel Emelyanov <xemul@openvz.org> Fri Jul 25 01:48:48 2008 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> Fri Jul 25 10:53:47 2008 -0700
tree d8471439c564bb15532c9dac041d0787faee2c90
parent b5a7174875ea570cc675f2c503e800db8efdd6a7

bsdacct: account dying tasks in all relevant namespaces

This just makes the acct_proces walk the pid namespaces from current up to
the top and account a task in each with the accounting turned on.

ns->parent access if safe lockless, since current it still alive and holds
its namespace, which in turn holds its parent.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/acct.c

diff --git a/kernel/acct.c b/kernel/acct.c
index 7fc9f9d..0feba97 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -631,15 +631,9 @@
 	spin_unlock_irq(&current->sighand->siglock);
 }
 
-/**
- * acct_process - now just a wrapper around do_acct_process
- *
- * handles process accounting for an exiting task
- */
-void acct_process(void)
+static void acct_process_in_ns(struct pid_namespace *ns)
 {
 	struct file *file = NULL;
-	struct pid_namespace *ns = task_active_pid_ns(current);
 	struct bsd_acct_struct *acct;
 
 	acct = ns->bacct;
@@ -661,3 +655,16 @@
 	do_acct_process(acct, ns, file);
 	fput(file);
 }
+
+/**
+ * acct_process - now just a wrapper around do_acct_process
+ *
+ * handles process accounting for an exiting task
+ */
+void acct_process(void)
+{
+	struct pid_namespace *ns;
+
+	for (ns = task_active_pid_ns(current); ns != NULL; ns = ns->parent)
+		acct_process_in_ns(ns);
+}