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Date: Fri, 16 May 2008 03:33:04 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 10/10] Bsdacct: account dying tasks in all relevant
 namespaces
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On Fri, 16 May 2008 14:11:04 +0400 Pavel Emelyanov <xemul@openvz.org> wrote:

> 
> >> + * 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);
> >> +}
> > 
> > Is it really safe to walk this list locklessly?
> 
> Well, yes - I wrote it in the comment to the 10th patch:
> 
>  "ns->parent access if safe lockless, since current it still
>   alive and holds its namespace, which in turn holds its parent."

oic.

> Should I also add this as a comment here?

It wouldn't hurt...