Commit a49b116d authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar

clockevents: Cleanup dead cpu explicitely

clockevents_notify() is a leftover from the early design of the
clockevents facility. It's really not a notification mechanism,
it's a multiplex call. We are way better off to have explicit
calls instead of this monstrosity.

Split out the cleanup function for a dead cpu and invoke it
directly from the cpu down code. Make it conditional on
CPU_HOTPLUG as well.

Temporary change, will be refined in the future.
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
[ Rebased, added clockevents_notify() removal ]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1735025.raBZdQHM3m@vostro.rjw.lanSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 52c063d1
......@@ -8,12 +8,6 @@
#ifndef _LINUX_CLOCKCHIPS_H
#define _LINUX_CLOCKCHIPS_H
/* Clock event notification values */
enum clock_event_nofitiers {
CLOCK_EVT_NOTIFY_ADD,
CLOCK_EVT_NOTIFY_CPU_DEAD,
};
#ifdef CONFIG_GENERIC_CLOCKEVENTS
# include <linux/clocksource.h>
......
......@@ -20,6 +20,7 @@ extern void tick_suspend_local(void);
/* Should be core only, but XEN resume magic and ARM BL switcher require it */
extern void tick_resume_local(void);
extern void tick_handover_do_timer(void);
extern void tick_cleanup_dead_cpu(int cpu);
#else /* CONFIG_GENERIC_CLOCKEVENTS */
static inline void tick_init(void) { }
static inline void tick_freeze(void) { }
......@@ -27,6 +28,7 @@ static inline void tick_unfreeze(void) { }
static inline void tick_suspend_local(void) { }
static inline void tick_resume_local(void) { }
static inline void tick_handover_do_timer(void) { }
static inline void tick_cleanup_dead_cpu(int cpu) { }
#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
#ifdef CONFIG_TICK_ONESHOT
......
......@@ -419,6 +419,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
__cpu_die(cpu);
/* CPU is completely dead: tell everyone. Too late to complain. */
tick_cleanup_dead_cpu(cpu);
cpu_notify_nofail(CPU_DEAD | mod, hcpu);
check_for_tasks(cpu);
......
......@@ -642,49 +642,40 @@ void clockevents_resume(void)
dev->resume(dev);
}
#ifdef CONFIG_HOTPLUG_CPU
/**
* clockevents_notify - notification about relevant events
* Returns 0 on success, any other value on error
* tick_cleanup_dead_cpu - Cleanup the tick and clockevents of a dead cpu
*/
int clockevents_notify(unsigned long reason, void *arg)
void tick_cleanup_dead_cpu(int cpu)
{
struct clock_event_device *dev, *tmp;
unsigned long flags;
int cpu, ret = 0;
raw_spin_lock_irqsave(&clockevents_lock, flags);
switch (reason) {
case CLOCK_EVT_NOTIFY_CPU_DEAD:
tick_shutdown_broadcast_oneshot(arg);
tick_shutdown_broadcast(arg);
tick_shutdown(arg);
/*
* Unregister the clock event devices which were
* released from the users in the notify chain.
*/
list_for_each_entry_safe(dev, tmp, &clockevents_released, list)
tick_shutdown_broadcast_oneshot(cpu);
tick_shutdown_broadcast(cpu);
tick_shutdown(cpu);
/*
* Unregister the clock event devices which were
* released from the users in the notify chain.
*/
list_for_each_entry_safe(dev, tmp, &clockevents_released, list)
list_del(&dev->list);
/*
* Now check whether the CPU has left unused per cpu devices
*/
list_for_each_entry_safe(dev, tmp, &clockevent_devices, list) {
if (cpumask_test_cpu(cpu, dev->cpumask) &&
cpumask_weight(dev->cpumask) == 1 &&
!tick_is_broadcast_device(dev)) {
BUG_ON(dev->state != CLOCK_EVT_STATE_DETACHED);
list_del(&dev->list);
/*
* Now check whether the CPU has left unused per cpu devices
*/
cpu = *((int *)arg);
list_for_each_entry_safe(dev, tmp, &clockevent_devices, list) {
if (cpumask_test_cpu(cpu, dev->cpumask) &&
cpumask_weight(dev->cpumask) == 1 &&
!tick_is_broadcast_device(dev)) {
BUG_ON(dev->state != CLOCK_EVT_STATE_DETACHED);
list_del(&dev->list);
}
}
break;
default:
break;
}
raw_spin_unlock_irqrestore(&clockevents_lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(clockevents_notify);
#endif
#ifdef CONFIG_SYSFS
struct bus_type clockevents_subsys = {
......
......@@ -1709,11 +1709,8 @@ static int hrtimer_cpu_notify(struct notifier_block *self,
#ifdef CONFIG_HOTPLUG_CPU
case CPU_DEAD:
case CPU_DEAD_FROZEN:
{
clockevents_notify(CLOCK_EVT_NOTIFY_CPU_DEAD, &scpu);
migrate_hrtimers(scpu);
break;
}
#endif
default:
......
......@@ -410,14 +410,14 @@ void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
dev->event_handler = tick_handle_periodic_broadcast;
}
#ifdef CONFIG_HOTPLUG_CPU
/*
* Remove a CPU from broadcasting
*/
void tick_shutdown_broadcast(unsigned int *cpup)
void tick_shutdown_broadcast(unsigned int cpu)
{
struct clock_event_device *bc;
unsigned long flags;
unsigned int cpu = *cpup;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
......@@ -432,6 +432,7 @@ void tick_shutdown_broadcast(unsigned int *cpup)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
#endif
void tick_suspend_broadcast(void)
{
......@@ -672,21 +673,6 @@ static void broadcast_shutdown_local(struct clock_event_device *bc,
clockevents_set_state(dev, CLOCK_EVT_STATE_SHUTDOWN);
}
void hotplug_cpu__broadcast_tick_pull(int deadcpu)
{
struct clock_event_device *bc;
unsigned long flags;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
bc = tick_broadcast_device.evtdev;
if (bc && broadcast_needs_cpu(bc, deadcpu)) {
/* This moves the broadcast assignment to this CPU: */
clockevents_program_event(bc, bc->next_event, 1);
}
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
/**
* tick_broadcast_oneshot_control - Enter/exit broadcast oneshot mode
* @state: The target state (enter/exit)
......@@ -908,14 +894,28 @@ void tick_broadcast_switch_to_oneshot(void)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
#ifdef CONFIG_HOTPLUG_CPU
void hotplug_cpu__broadcast_tick_pull(int deadcpu)
{
struct clock_event_device *bc;
unsigned long flags;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
bc = tick_broadcast_device.evtdev;
if (bc && broadcast_needs_cpu(bc, deadcpu)) {
/* This moves the broadcast assignment to this CPU: */
clockevents_program_event(bc, bc->next_event, 1);
}
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
/*
* Remove a dead CPU from broadcasting
*/
void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
void tick_shutdown_broadcast_oneshot(unsigned int cpu)
{
unsigned long flags;
unsigned int cpu = *cpup;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
......@@ -929,6 +929,7 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
#endif
/*
* Check, whether the broadcast device is in one shot mode
......
......@@ -348,7 +348,6 @@ void tick_handover_do_timer(void)
TICK_DO_TIMER_NONE;
}
}
#endif
/*
* Shutdown an event device on a given cpu:
......@@ -357,9 +356,9 @@ void tick_handover_do_timer(void)
* access the hardware device itself.
* We just set the mode and remove it from the lists.
*/
void tick_shutdown(unsigned int *cpup)
void tick_shutdown(unsigned int cpu)
{
struct tick_device *td = &per_cpu(tick_cpu_device, *cpup);
struct tick_device *td = &per_cpu(tick_cpu_device, cpu);
struct clock_event_device *dev = td->evtdev;
td->mode = TICKDEV_MODE_PERIODIC;
......@@ -375,6 +374,7 @@ void tick_shutdown(unsigned int *cpup)
td->evtdev = NULL;
}
}
#endif
/**
* tick_suspend_local - Suspend the local tick device
......
......@@ -20,7 +20,7 @@ extern int tick_do_timer_cpu __read_mostly;
extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
extern void tick_handle_periodic(struct clock_event_device *dev);
extern void tick_check_new_device(struct clock_event_device *dev);
extern void tick_shutdown(unsigned int *cpup);
extern void tick_shutdown(unsigned int cpu);
extern void tick_suspend(void);
extern void tick_resume(void);
extern bool tick_check_replacement(struct clock_event_device *curdev,
......@@ -52,7 +52,7 @@ extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
extern void tick_install_broadcast_device(struct clock_event_device *dev);
extern int tick_is_broadcast_device(struct clock_event_device *dev);
extern void tick_shutdown_broadcast(unsigned int *cpup);
extern void tick_shutdown_broadcast(unsigned int cpu);
extern void tick_suspend_broadcast(void);
extern void tick_resume_broadcast(void);
extern bool tick_resume_check_broadcast(void);
......@@ -66,7 +66,7 @@ static inline void tick_install_broadcast_device(struct clock_event_device *dev)
static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
static inline void tick_shutdown_broadcast(unsigned int *cpup) { }
static inline void tick_shutdown_broadcast(unsigned int cpu) { }
static inline void tick_suspend_broadcast(void) { }
static inline void tick_resume_broadcast(void) { }
static inline bool tick_resume_check_broadcast(void) { return false; }
......@@ -117,7 +117,7 @@ static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
extern void tick_broadcast_switch_to_oneshot(void);
extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
extern int tick_broadcast_oneshot_active(void);
extern void tick_check_oneshot_broadcast_this_cpu(void);
bool tick_broadcast_oneshot_available(void);
......@@ -125,7 +125,7 @@ extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
#else /* !(BROADCAST && ONESHOT): */
static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
static inline void tick_broadcast_switch_to_oneshot(void) { }
static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
static inline int tick_broadcast_oneshot_active(void) { return 0; }
static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
......
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