cputime: Use accessors to read task cputime stats

This is in preparation for the full dynticks feature. While
remotely reading the cputime of a task running in a full
dynticks CPU, we'll need to do some extra-computation. This
way we can account the time it spent tickless in userspace
since its last cputime snapshot.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

drivers/isdn/mISDN/stack.c

@@ -18,6 +18,7 @@
 #include <linux/slab.h>
 #include <linux/mISDNif.h>
 #include <linux/kthread.h>
+#include <linux/sched.h>
 #include "core.h"
 
 static u_int	*debug;
@@ -202,6 +203,9 @@ static int
 mISDNStackd(void *data)
 {
 	struct mISDNstack *st = data;
+#ifdef MISDN_MSG_STATS
+	cputime_t utime, stime;
+#endif
 	int err = 0;
 
 	sigfillset(&current->blocked);
@@ -303,9 +307,10 @@ mISDNStackd(void *data)
 	       "msg %d sleep %d stopped\n",
 	       dev_name(&st->dev->dev), st->msg_cnt, st->sleep_cnt,
 	       st->stopped_cnt);
+	task_cputime(st->thread, &utime, &stime);
 	printk(KERN_DEBUG
 	       "mISDNStackd daemon for %s utime(%ld) stime(%ld)\n",
-	       dev_name(&st->dev->dev), st->thread->utime, st->thread->stime);
+	       dev_name(&st->dev->dev), utime, stime);
 	printk(KERN_DEBUG
 	       "mISDNStackd daemon for %s nvcsw(%ld) nivcsw(%ld)\n",
 	       dev_name(&st->dev->dev), st->thread->nvcsw, st->thread->nivcsw);