Use helpers to obtain task pid in printks

The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/oom_kill.c

@@ -278,7 +278,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose)
 	}
 
 	if (verbose)
-		printk(KERN_ERR "Killed process %d (%s)\n", p->pid, p->comm);
+		printk(KERN_ERR "Killed process %d (%s)\n",
+				task_pid_nr(p), p->comm);
 
 	/*
 	 * We give our sacrificial lamb high priority and access to
@@ -356,7 +357,7 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
 	}
 
 	printk(KERN_ERR "%s: kill process %d (%s) score %li or a child\n",
-					message, p->pid, p->comm, points);
+					message, task_pid_nr(p), p->comm, points);
 
 	/* Try to kill a child first */
 	list_for_each_entry(c, &p->children, sibling) {