Merge branch 'rcu/nohz' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into timers/nohz

Pull full dynticks documentation update from Paul McKenney.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h
index a8ece9a..2c9e62c 100644
--- a/include/asm-generic/cputime_nsecs.h
+++ b/include/asm-generic/cputime_nsecs.h
@@ -16,21 +16,27 @@
 #ifndef _ASM_GENERIC_CPUTIME_NSECS_H
 #define _ASM_GENERIC_CPUTIME_NSECS_H
 
+#include <linux/math64.h>
+
 typedef u64 __nocast cputime_t;
 typedef u64 __nocast cputime64_t;
 
 #define cputime_one_jiffy		jiffies_to_cputime(1)
 
+#define cputime_div(__ct, divisor)  div_u64((__force u64)__ct, divisor)
+#define cputime_div_rem(__ct, divisor, remainder) \
+	div_u64_rem((__force u64)__ct, divisor, remainder);
+
 /*
  * Convert cputime <-> jiffies (HZ)
  */
 #define cputime_to_jiffies(__ct)	\
-	((__force u64)(__ct) / (NSEC_PER_SEC / HZ))
+	cputime_div(__ct, NSEC_PER_SEC / HZ)
 #define cputime_to_scaled(__ct)		(__ct)
 #define jiffies_to_cputime(__jif)	\
 	(__force cputime_t)((__jif) * (NSEC_PER_SEC / HZ))
 #define cputime64_to_jiffies64(__ct)	\
-	((__force u64)(__ct) / (NSEC_PER_SEC / HZ))
+	cputime_div(__ct, NSEC_PER_SEC / HZ)
 #define jiffies64_to_cputime64(__jif)	\
 	(__force cputime64_t)((__jif) * (NSEC_PER_SEC / HZ))
 
@@ -45,7 +51,7 @@
  * Convert cputime <-> microseconds
  */
 #define cputime_to_usecs(__ct)		\
-	((__force u64)(__ct) / NSEC_PER_USEC)
+	cputime_div(__ct, NSEC_PER_USEC)
 #define usecs_to_cputime(__usecs)	\
 	(__force cputime_t)((__usecs) * NSEC_PER_USEC)
 #define usecs_to_cputime64(__usecs)	\
@@ -55,7 +61,7 @@
  * Convert cputime <-> seconds
  */
 #define cputime_to_secs(__ct)		\
-	((__force u64)(__ct) / NSEC_PER_SEC)
+	cputime_div(__ct, NSEC_PER_SEC)
 #define secs_to_cputime(__secs)		\
 	(__force cputime_t)((__secs) * NSEC_PER_SEC)
 
@@ -69,8 +75,10 @@
 }
 static inline void cputime_to_timespec(const cputime_t ct, struct timespec *val)
 {
-	val->tv_sec  = (__force u64) ct / NSEC_PER_SEC;
-	val->tv_nsec = (__force u64) ct % NSEC_PER_SEC;
+	u32 rem;
+
+	val->tv_sec = cputime_div_rem(ct, NSEC_PER_SEC, &rem);
+	val->tv_nsec = rem;
 }
 
 /*
@@ -83,15 +91,17 @@
 }
 static inline void cputime_to_timeval(const cputime_t ct, struct timeval *val)
 {
-	val->tv_sec = (__force u64) ct / NSEC_PER_SEC;
-	val->tv_usec = ((__force u64) ct % NSEC_PER_SEC) / NSEC_PER_USEC;
+	u32 rem;
+
+	val->tv_sec = cputime_div_rem(ct, NSEC_PER_SEC, &rem);
+	val->tv_usec = rem / NSEC_PER_USEC;
 }
 
 /*
  * Convert cputime <-> clock (USER_HZ)
  */
 #define cputime_to_clock_t(__ct)	\
-	((__force u64)(__ct) / (NSEC_PER_SEC / USER_HZ))
+	cputime_div(__ct, (NSEC_PER_SEC / USER_HZ))
 #define clock_t_to_cputime(__x)		\
 	(__force cputime_t)((__x) * (NSEC_PER_SEC / USER_HZ))
 
diff --git a/init/Kconfig b/init/Kconfig
index edc8132..8f97a74 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -306,7 +306,7 @@
 # Kind of a stub config for the pure tick based cputime accounting
 config TICK_CPU_ACCOUNTING
 	bool "Simple tick based cputime accounting"
-	depends on !S390
+	depends on !S390 && !NO_HZ_FULL
 	help
 	  This is the basic tick based cputime accounting that maintains
 	  statistics about user, system and idle time spent on per jiffies
@@ -316,7 +316,7 @@
 
 config VIRT_CPU_ACCOUNTING_NATIVE
 	bool "Deterministic task and CPU time accounting"
-	depends on HAVE_VIRT_CPU_ACCOUNTING
+	depends on HAVE_VIRT_CPU_ACCOUNTING && !NO_HZ_FULL
 	select VIRT_CPU_ACCOUNTING
 	help
 	  Select this option to enable more accurate task and CPU time
@@ -346,7 +346,7 @@
 
 config IRQ_TIME_ACCOUNTING
 	bool "Fine granularity task level IRQ time accounting"
-	depends on HAVE_IRQ_TIME_ACCOUNTING
+	depends on HAVE_IRQ_TIME_ACCOUNTING && !NO_HZ_FULL
 	help
 	  Select this option to enable fine granularity task irq time
 	  accounting. This is done by reading a timestamp on each
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 1ea2bba..a2ddd65 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -104,11 +104,13 @@
 	depends on SMP
 	# RCU_USER_QS dependency
 	depends on HAVE_CONTEXT_TRACKING
-	depends on VIRT_CPU_ACCOUNTING_GEN
+	# VIRT_CPU_ACCOUNTING_GEN dependency
+	depends on 64BIT
 	select NO_HZ_COMMON
 	select RCU_USER_QS
 	select RCU_NOCB_CPU
 	select RCU_NOCB_CPU_ALL
+	select VIRT_CPU_ACCOUNTING_GEN
 	select CONTEXT_TRACKING_FORCE
 	select IRQ_WORK
 	help
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index da53c8f..1c9f53b 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -251,14 +251,15 @@
 {
 	unsigned long flags;
 
-	if (!tick_nohz_full_cpu(smp_processor_id()))
-		return;
-
 	local_irq_save(flags);
 
+	if (!tick_nohz_full_cpu(smp_processor_id()))
+		goto out;
+
 	if (tick_nohz_tick_stopped() && !can_stop_full_tick())
 		tick_nohz_full_kick();
 
+out:
 	local_irq_restore(flags);
 }