path: root/kernel
diff options
authorLinus Torvalds <>2014-04-17 16:19:10 -0700
committerLinus Torvalds <>2014-04-17 16:19:10 -0700
commit87a54cae0ba094de2ddb7e5f429fd32b965a2fbf (patch)
treec8a990e39250a2c3ee8b47448d4252fc3da55c9b /kernel
parent81cef0fe19e086ff6abfd45e92246f68ffa0185f (diff)
parent27630532ef5ead28b98cfe28d8f95222ef91c2b7 (diff)
Merge branch 'timers-urgent-for-linus' of git://
Pull timer fixes from Thomas Gleixner: "Viresh unearthed the following three hickups in the timer/timekeeping code: - Negated check for the result of a clock event selection - A missing early exit in the jiffies update path which causes update_wall_time to be called for nothing causing lock contention and wasted cycles in the timer interrupt - Checking a variable in the NOHZ code enable code for true which can only be set by that very code after the check succeeds. That results in a rock solid runtime disablement of that feature" * 'timers-urgent-for-linus' of git:// tick-sched: Check tick_nohz_enabled in tick_nohz_switch_to_nohz() tick-sched: Don't call update_wall_time() when delta is lesser than tick_period tick-common: Fix wrong check in tick_check_replacement()
Diffstat (limited to 'kernel')
2 files changed, 5 insertions, 2 deletions
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index 0156612..0a0608e 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -276,7 +276,7 @@ static bool tick_check_preferred(struct clock_event_device *curdev,
bool tick_check_replacement(struct clock_event_device *curdev,
struct clock_event_device *newdev)
- if (tick_check_percpu(curdev, newdev, smp_processor_id()))
+ if (!tick_check_percpu(curdev, newdev, smp_processor_id()))
return false;
return tick_check_preferred(curdev, newdev);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 9f8af69..6558b7a 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -84,6 +84,9 @@ static void tick_do_update_jiffies64(ktime_t now)
/* Keep the tick_next_period variable up to date */
tick_next_period = ktime_add(last_jiffies_update, tick_period);
+ } else {
+ write_sequnlock(&jiffies_lock);
+ return;
@@ -967,7 +970,7 @@ static void tick_nohz_switch_to_nohz(void)
struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched);
ktime_t next;
- if (!tick_nohz_active)
+ if (!tick_nohz_enabled)