[IA64] make pfm_get_task work with virtual pids

This pid comes from user space, so treat it accordingly.

Signed-off-by: Pavel Emelyanov <[e-mail]>
Cc: "Eric W. Biederman" <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Tony Luck <[e-mail]>

arch/ia64/kernel/perfmon.c

···
 	/* XXX: need to add more checks here */
 	if (pid < 2) return -EPERM;
 
-	if (pid != current->pid) {
+	if (pid != task_pid_vnr(current)) {
 
 		read_lock(&tasklist_lock);
 
-		p = find_task_by_pid(pid);
+		p = find_task_by_vpid(pid);
 
 		/* make sure task cannot go away while we operate on it */
 		if (p) get_task_struct(p);