Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  timers: fix TIMER_ABSTIME for process wide cpu timers
  timers: split process wide cpu clocks/timers, fix
  x86: clean up hpet timer reinit
  timers: split process wide cpu clocks/timers, remove spurious warning
  timers: split process wide cpu clocks/timers
  signal: re-add dead task accumulation stats.
  x86: fix hpet timer reinit for x86_64
  sched: fix nohz load balancer on cpu offline

2 files changed, 39 insertions, 36 deletions

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index ea0ea1a4c36f..e752d973fa21 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -48,12 +48,11 @@ extern struct fs_struct init_fs;
 	.posix_timers	 = LIST_HEAD_INIT(sig.posix_timers),		\
 	.cpu_timers	= INIT_CPU_TIMERS(sig.cpu_timers),		\
 	.rlim		= INIT_RLIMITS,					\
-	.cputime	= { .totals = {					\
-		.utime = cputime_zero,					\
-		.stime = cputime_zero,					\
-		.sum_exec_runtime = 0,					\
-		.lock = __SPIN_LOCK_UNLOCKED(sig.cputime.totals.lock),	\
-	}, },								\
+	.cputimer	= { 						\
+		.cputime = INIT_CPUTIME,				\
+		.running = 0,						\
+		.lock = __SPIN_LOCK_UNLOCKED(sig.cputimer.lock),	\
+	},								\
 }
 
 extern struct nsproxy init_nsproxy;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 2127e959e0f4..8981e52c714f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -443,7 +443,6 @@ struct pacct_struct {
  * @utime:		time spent in user mode, in &cputime_t units
  * @stime:		time spent in kernel mode, in &cputime_t units
  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
- * @lock:		lock for fields in this struct
  *
  * This structure groups together three kinds of CPU time that are
  * tracked for threads and thread groups.  Most things considering
@@ -454,23 +453,33 @@ struct task_cputime {
 	cputime_t utime;
 	cputime_t stime;
 	unsigned long long sum_exec_runtime;
-	spinlock_t lock;
 };
 /* Alternate field names when used to cache expirations. */
 #define prof_exp	stime
 #define virt_exp	utime
 #define sched_exp	sum_exec_runtime
 
+#define INIT_CPUTIME	\
+	(struct task_cputime) {					\
+		.utime = cputime_zero,				\
+		.stime = cputime_zero,				\
+		.sum_exec_runtime = 0,				\
+	}
+
 /**
- * struct thread_group_cputime - thread group interval timer counts
- * @totals:		thread group interval timers; substructure for
- *			uniprocessor kernel, per-cpu for SMP kernel.
+ * struct thread_group_cputimer - thread group interval timer counts
+ * @cputime:		thread group interval timers.
+ * @running:		non-zero when there are timers running and
+ * 			@cputime receives updates.
+ * @lock:		lock for fields in this struct.
  *
  * This structure contains the version of task_cputime, above, that is
- * used for thread group CPU clock calculations.
+ * used for thread group CPU timer calculations.
  */
-struct thread_group_cputime {
-	struct task_cputime totals;
+struct thread_group_cputimer {
+	struct task_cputime cputime;
+	int running;
+	spinlock_t lock;
 };
 
 /*
@@ -519,10 +528,10 @@ struct signal_struct {
 	cputime_t it_prof_incr, it_virt_incr;
 
 	/*
-	 * Thread group totals for process CPU clocks.
-	 * See thread_group_cputime(), et al, for details.
+	 * Thread group totals for process CPU timers.
+	 * See thread_group_cputimer(), et al, for details.
 	 */
-	struct thread_group_cputime cputime;
+	struct thread_group_cputimer cputimer;
 
 	/* Earliest-expiration cache. */
 	struct task_cputime cputime_expires;
@@ -559,7 +568,7 @@ struct signal_struct {
 	 * Live threads maintain their own counters and add to these
 	 * in __exit_signal, except for the group leader.
 	 */
-	cputime_t cutime, cstime;
+	cputime_t utime, stime, cutime, cstime;
 	cputime_t gtime;
 	cputime_t cgtime;
 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
@@ -568,6 +577,14 @@ struct signal_struct {
 	struct task_io_accounting ioac;
 
 	/*
+	 * Cumulative ns of schedule CPU time fo dead threads in the
+	 * group, not including a zombie group leader, (This only differs
+	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
+	 * other than jiffies.)
+	 */
+	unsigned long long sum_sched_runtime;
+
+	/*
 	 * We don't bother to synchronize most readers of this at all,
 	 * because there is no reader checking a limit that actually needs
 	 * to get both rlim_cur and rlim_max atomically, and either one
@@ -2183,27 +2200,14 @@ static inline int spin_needbreak(spinlock_t *lock)
 /*
  * Thread group CPU time accounting.
  */
-
-static inline
-void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
-{
-	struct task_cputime *totals = &tsk->signal->cputime.totals;
-	unsigned long flags;
-
-	spin_lock_irqsave(&totals->lock, flags);
-	*times = *totals;
-	spin_unlock_irqrestore(&totals->lock, flags);
-}
+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
+void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
 
 static inline void thread_group_cputime_init(struct signal_struct *sig)
 {
-	sig->cputime.totals = (struct task_cputime){
-		.utime = cputime_zero,
-		.stime = cputime_zero,
-		.sum_exec_runtime = 0,
-	};
-
-	spin_lock_init(&sig->cputime.totals.lock);
+	sig->cputimer.cputime = INIT_CPUTIME;
+	spin_lock_init(&sig->cputimer.lock);
+	sig->cputimer.running = 0;
 }
 
 static inline void thread_group_cputime_free(struct signal_struct *sig)