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:
  nohz: adjust tick_nohz_stop_sched_tick() call of s390 as well
  nohz: prevent tick stop outside of the idle loop

15 files changed, 27 insertions, 18 deletions

diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 199b3680118b..89bfded70a1f 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -162,7 +162,7 @@ void cpu_idle(void)
                 if (!idle)
                         idle = default_idle;
                 leds_event(led_idle_start);
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched())
                         idle();
                 leds_event(led_idle_end);
diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c
index 6cf9df176274..ff820a9e743a 100644
--- a/arch/avr32/kernel/process.c
+++ b/arch/avr32/kernel/process.c
@@ -31,7 +31,7 @@ void cpu_idle(void)
 {
         /* endless idle loop with no priority at all */
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched())
                         cpu_idle_sleep();
                 tick_nohz_restart_sched_tick();
diff --git a/arch/blackfin/kernel/process.c b/arch/blackfin/kernel/process.c
index 53c2cd255441..77800dd83e57 100644
--- a/arch/blackfin/kernel/process.c
+++ b/arch/blackfin/kernel/process.c
@@ -105,7 +105,7 @@ void cpu_idle(void)
 #endif
                 if (!idle)
                         idle = default_idle;
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched())
                         idle();
                 tick_nohz_restart_sched_tick();
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index c06f5b5d764c..b16facd9ea8e 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -53,7 +53,7 @@ void __noreturn cpu_idle(void)
 {
         /* endless idle loop with no priority at all */
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched()) {
 #ifdef CONFIG_SMTC_IDLE_HOOK_DEBUG
                         extern void smtc_idle_loop_hook(void);
diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index c3cf0e8f3ac1..d308a9f70f1b 100644
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -60,7 +60,7 @@ void cpu_idle(void)
 
         set_thread_flag(TIF_POLLING_NRFLAG);
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched() && !cpu_should_die()) {
                         ppc64_runlatch_off();
 
diff --git a/arch/powerpc/platforms/iseries/setup.c b/arch/powerpc/platforms/iseries/setup.c
index b72120751bbe..70b688c1aefb 100644
--- a/arch/powerpc/platforms/iseries/setup.c
+++ b/arch/powerpc/platforms/iseries/setup.c
@@ -561,7 +561,7 @@ static void yield_shared_processor(void)
 static void iseries_shared_idle(void)
 {
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched() && !hvlpevent_is_pending()) {
                         local_irq_disable();
                         ppc64_runlatch_off();
@@ -591,7 +591,7 @@ static void iseries_dedicated_idle(void)
         set_thread_flag(TIF_POLLING_NRFLAG);
 
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 if (!need_resched()) {
                         while (!need_resched()) {
                                 ppc64_runlatch_off();
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 85defd01d293..9839767d0842 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -142,7 +142,7 @@ static void default_idle(void)
 void cpu_idle(void)
 {
         for (;;) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched())
                         default_idle();
                 tick_nohz_restart_sched_tick();
diff --git a/arch/sh/kernel/process_32.c b/arch/sh/kernel/process_32.c
index b98e37a1f54c..921892c351da 100644
--- a/arch/sh/kernel/process_32.c
+++ b/arch/sh/kernel/process_32.c
@@ -86,7 +86,7 @@ void cpu_idle(void)
                 if (!idle)
                         idle = default_idle;
 
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched())
                         idle();
                 tick_nohz_restart_sched_tick();
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 31ea752d307b..8a9cd3e165b9 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -96,7 +96,7 @@ void cpu_idle(void)
         set_thread_flag(TIF_POLLING_NRFLAG);
 
         while(1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
 
                 while (!need_resched() && !cpu_is_offline(cpu))
                         sparc64_yield(cpu);
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 83603cfbde81..a1c6d07cac3e 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -243,7 +243,7 @@ void default_idle(void)
                 if (need_resched())
                         schedule();
 
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 nsecs = disable_timer();
                 idle_sleep(nsecs);
                 tick_nohz_restart_sched_tick();
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 0c3927accb00..53bc653ed5ca 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -128,7 +128,7 @@ void cpu_idle(void)
 
         /* endless idle loop with no priority at all */
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched()) {
 
                         check_pgt_cache();
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e8a8e1b99817..3fb62a7d9a16 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -120,7 +120,7 @@ void cpu_idle(void)
         current_thread_info()->status |= TS_POLLING;
         /* endless idle loop with no priority at all */
         while (1) {
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(1);
                 while (!need_resched()) {
 
                         rmb();
diff --git a/include/linux/tick.h b/include/linux/tick.h
index a881c652f7e9..d3c02695dc5d 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -49,6 +49,7 @@ struct tick_sched {
         unsigned long                   check_clocks;
         enum tick_nohz_mode             nohz_mode;
         ktime_t                         idle_tick;
+        int                             inidle;
         int                             tick_stopped;
         unsigned long                   idle_jiffies;
         unsigned long                   idle_calls;
@@ -105,14 +106,14 @@ static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
 
 # ifdef CONFIG_NO_HZ
-extern void tick_nohz_stop_sched_tick(void);
+extern void tick_nohz_stop_sched_tick(int inidle);
 extern void tick_nohz_restart_sched_tick(void);
 extern void tick_nohz_update_jiffies(void);
 extern ktime_t tick_nohz_get_sleep_length(void);
 extern void tick_nohz_stop_idle(int cpu);
 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
 # else
-static inline void tick_nohz_stop_sched_tick(void) { }
+static inline void tick_nohz_stop_sched_tick(int inidle) { }
 static inline void tick_nohz_restart_sched_tick(void) { }
 static inline void tick_nohz_update_jiffies(void) { }
 static inline ktime_t tick_nohz_get_sleep_length(void)
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 81e2fe0f983a..f6b03d56c2bf 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -286,7 +286,7 @@ void irq_exit(void)
 #ifdef CONFIG_NO_HZ
         /* Make sure that timer wheel updates are propagated */
         if (!in_interrupt() && idle_cpu(smp_processor_id()) && !need_resched())
-                tick_nohz_stop_sched_tick();
+                tick_nohz_stop_sched_tick(0);
         rcu_irq_exit();
 #endif
         preempt_enable_no_resched();
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 942fc7c85283..825b4c00fe44 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -195,7 +195,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
  * Called either from the idle loop or from irq_exit() when an idle period was
  * just interrupted by an interrupt which did not cause a reschedule.
  */
-void tick_nohz_stop_sched_tick(void)
+void tick_nohz_stop_sched_tick(int inidle)
 {
         unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags;
         struct tick_sched *ts;
@@ -224,6 +224,11 @@ void tick_nohz_stop_sched_tick(void)
         if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
                 goto end;
 
+        if (!inidle && !ts->inidle)
+                goto end;
+
+        ts->inidle = 1;
+
         if (need_resched())
                 goto end;
 
@@ -373,11 +378,14 @@ void tick_nohz_restart_sched_tick(void)
         local_irq_disable();
         tick_nohz_stop_idle(cpu);
 
-        if (!ts->tick_stopped) {
+        if (!ts->inidle || !ts->tick_stopped) {
+                ts->inidle = 0;
                 local_irq_enable();
                 return;
         }
 
+        ts->inidle = 0;
+
         rcu_exit_nohz();
 
         /* Update jiffies first */