From fc1f7d5606487ae28d6c84e95401952927d7379e Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:43 +0000 Subject: clocksource: apb_timer: Remove unsused function Signed-off-by: Thomas Gleixner Acked-by: John Stultz Cc: Magnus Damm Acked-by: Jamie Iles Link: http://lkml.kernel.org/r/20130425143435.558006195@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/dw_apb_timer.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include') diff --git a/include/linux/dw_apb_timer.h b/include/linux/dw_apb_timer.h index dd755ce2a5eb..b1cd9597c241 100644 --- a/include/linux/dw_apb_timer.h +++ b/include/linux/dw_apb_timer.h @@ -51,7 +51,6 @@ dw_apb_clocksource_init(unsigned rating, const char *name, void __iomem *base, void dw_apb_clocksource_register(struct dw_apb_clocksource *dw_cs); void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs); cycle_t dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs); -void dw_apb_clocksource_unregister(struct dw_apb_clocksource *dw_cs); extern void dw_apb_timer_init(void); #endif /* __DW_APB_TIMER_H__ */ -- cgit v1.2.3 From ba919d1caa2e624eb8c6cae1f2ce0a253e697d45 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:44 +0000 Subject: clocksource: Let timekeeping_notify return success/error timekeeping_notify() can fail due cs->enable() failure. Though the caller does not notice and happily keeps the wrong clocksource as the current one. Let the caller know about failure, so the current clocksource will be shown correctly in sysfs. Signed-off-by: Thomas Gleixner Acked-by: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143435.696321912@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 2 +- kernel/time/clocksource.c | 6 +++--- kernel/time/timekeeping.c | 5 +++-- 3 files changed, 7 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 7279b94c01da..aa6ba44e75d5 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -321,7 +321,7 @@ static inline void __clocksource_updatefreq_khz(struct clocksource *cs, u32 khz) } -extern void timekeeping_notify(struct clocksource *clock); +extern int timekeeping_notify(struct clocksource *clock); extern cycle_t clocksource_mmio_readl_up(struct clocksource *); extern cycle_t clocksource_mmio_readl_down(struct clocksource *); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index dda5c7130d93..1923a340bd91 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -611,10 +611,10 @@ static void clocksource_select(void) best = cs; break; } - if (curr_clocksource != best) { - printk(KERN_INFO "Switching to clocksource %s\n", best->name); + + if (curr_clocksource != best && !timekeeping_notify(best)) { + pr_info("Switched to clocksource %s\n", best->name); curr_clocksource = best; - timekeeping_notify(curr_clocksource); } } diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 98cd470bbe49..da6e10c7a378 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -648,14 +648,15 @@ static int change_clocksource(void *data) * This function is called from clocksource.c after a new, better clock * source has been registered. The caller holds the clocksource_mutex. */ -void timekeeping_notify(struct clocksource *clock) +int timekeeping_notify(struct clocksource *clock) { struct timekeeper *tk = &timekeeper; if (tk->clock == clock) - return; + return 0; stop_machine(change_clocksource, clock, NULL); tick_clock_notify(); + return tk->clock == clock ? 0 : -1; } /** -- cgit v1.2.3 From 09ac369c825d9d593404306d59062d854b321e9b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:44 +0000 Subject: clocksource: Add module refcount Add a module refcount, so the current clocksource cannot be removed unconditionally. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143435.762417789@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 3 +++ kernel/time/timekeeping.c | 19 ++++++++++++++----- 2 files changed, 17 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index aa6ba44e75d5..32a895b114d8 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -21,6 +21,7 @@ /* clocksource cycle base type */ typedef u64 cycle_t; struct clocksource; +struct module; #ifdef CONFIG_ARCH_CLOCKSOURCE_DATA #include @@ -162,6 +163,7 @@ extern u64 timecounter_cyc2time(struct timecounter *tc, * @suspend: suspend function for the clocksource, if necessary * @resume: resume function for the clocksource, if necessary * @cycle_last: most recent cycle counter value seen by ::read() + * @owner: module reference, must be set by clocksource in modules */ struct clocksource { /* @@ -195,6 +197,7 @@ struct clocksource { cycle_t cs_last; cycle_t wd_last; #endif + struct module *owner; } ____cacheline_aligned; /* diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index da6e10c7a378..933efa4071c3 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -627,11 +627,20 @@ static int change_clocksource(void *data) write_seqcount_begin(&timekeeper_seq); timekeeping_forward_now(tk); - if (!new->enable || new->enable(new) == 0) { - old = tk->clock; - tk_setup_internals(tk, new); - if (old->disable) - old->disable(old); + /* + * If the cs is in module, get a module reference. Succeeds + * for built-in code (owner == NULL) as well. + */ + if (try_module_get(new->owner)) { + if (!new->enable || new->enable(new) == 0) { + old = tk->clock; + tk_setup_internals(tk, new); + if (old->disable) + old->disable(old); + module_put(old->owner); + } else { + module_put(new->owner); + } } timekeeping_update(tk, true, true); -- cgit v1.2.3 From a89c7edbe7d7aa80f507915f3dd801211b116b79 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:46 +0000 Subject: clocksource: Let clocksource_unregister() return success/error The unregister call can fail, if the clocksource is the current one and there is no replacement clocksource available. It can also fail, if the clocksource is the watchdog clocksource and I'm not going to provide support for this. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143436.029915527@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clocksource.h | 2 +- kernel/time/clocksource.c | 33 ++++++++++++--------------------- 2 files changed, 13 insertions(+), 22 deletions(-) (limited to 'include') diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h index 32a895b114d8..2f39a4911668 100644 --- a/include/linux/clocksource.h +++ b/include/linux/clocksource.h @@ -282,7 +282,7 @@ static inline s64 clocksource_cyc2ns(cycle_t cycles, u32 mult, u32 shift) extern int clocksource_register(struct clocksource*); -extern void clocksource_unregister(struct clocksource*); +extern int clocksource_unregister(struct clocksource*); extern void clocksource_touch_watchdog(void); extern struct clocksource* clocksource_get_next(void); extern void clocksource_change_rating(struct clocksource *cs, int rating); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 791d1aeb17ac..31b90332f47b 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -389,28 +389,17 @@ static void clocksource_enqueue_watchdog(struct clocksource *cs) static void clocksource_dequeue_watchdog(struct clocksource *cs) { - struct clocksource *tmp; unsigned long flags; spin_lock_irqsave(&watchdog_lock, flags); - if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) { - /* cs is a watched clocksource. */ - list_del_init(&cs->wd_list); - } else if (cs == watchdog) { - /* Reset watchdog cycles */ - clocksource_reset_watchdog(); - /* Current watchdog is removed. Find an alternative. */ - watchdog = NULL; - list_for_each_entry(tmp, &clocksource_list, list) { - if (tmp == cs || tmp->flags & CLOCK_SOURCE_MUST_VERIFY) - continue; - if (!watchdog || tmp->rating > watchdog->rating) - watchdog = tmp; + if (cs != watchdog) { + if (cs->flags & CLOCK_SOURCE_MUST_VERIFY) { + /* cs is a watched clocksource. */ + list_del_init(&cs->wd_list); + /* Check if the watchdog timer needs to be stopped. */ + clocksource_stop_watchdog(); } } - cs->flags &= ~CLOCK_SOURCE_WATCHDOG; - /* Check if the watchdog timer needs to be stopped. */ - clocksource_stop_watchdog(); spin_unlock_irqrestore(&watchdog_lock, flags); } @@ -841,13 +830,15 @@ static int clocksource_unbind(struct clocksource *cs) * clocksource_unregister - remove a registered clocksource * @cs: clocksource to be unregistered */ -void clocksource_unregister(struct clocksource *cs) +int clocksource_unregister(struct clocksource *cs) { + int ret = 0; + mutex_lock(&clocksource_mutex); - clocksource_dequeue_watchdog(cs); - list_del(&cs->list); - clocksource_select(); + if (!list_empty(&cs->list)) + ret = clocksource_unbind(cs); mutex_unlock(&clocksource_mutex); + return ret; } EXPORT_SYMBOL(clocksource_unregister); -- cgit v1.2.3 From 7172a286ced0c1f4f239a0fa09db54ed37d3ead2 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:47 +0000 Subject: clockevents: Get rid of the notifier chain 7+ years and still a single user. Kill it. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143436.098520211@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clockchips.h | 1 - kernel/time/clockevents.c | 35 +++-------------------------------- kernel/time/tick-broadcast.c | 5 ++--- kernel/time/tick-common.c | 30 +++++------------------------- kernel/time/tick-internal.h | 7 ++++--- 5 files changed, 14 insertions(+), 64 deletions(-) (limited to 'include') diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h index 963d71431388..2f498f66c1bb 100644 --- a/include/linux/clockchips.h +++ b/include/linux/clockchips.h @@ -150,7 +150,6 @@ extern void clockevents_exchange_device(struct clock_event_device *old, struct clock_event_device *new); extern void clockevents_set_mode(struct clock_event_device *dev, enum clock_event_mode mode); -extern int clockevents_register_notifier(struct notifier_block *nb); extern int clockevents_program_event(struct clock_event_device *dev, ktime_t expires, bool force); diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index c6d6400ee137..dd70b4842c62 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -15,7 +15,6 @@ #include #include #include -#include #include #include "tick-internal.h" @@ -23,10 +22,6 @@ /* The registered clock event devices */ static LIST_HEAD(clockevent_devices); static LIST_HEAD(clockevents_released); - -/* Notification for clock events */ -static RAW_NOTIFIER_HEAD(clockevents_chain); - /* Protection for the above */ static DEFINE_RAW_SPINLOCK(clockevents_lock); @@ -232,30 +227,6 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires, return (rc && force) ? clockevents_program_min_delta(dev) : rc; } -/** - * clockevents_register_notifier - register a clock events change listener - */ -int clockevents_register_notifier(struct notifier_block *nb) -{ - unsigned long flags; - int ret; - - raw_spin_lock_irqsave(&clockevents_lock, flags); - ret = raw_notifier_chain_register(&clockevents_chain, nb); - raw_spin_unlock_irqrestore(&clockevents_lock, flags); - - return ret; -} - -/* - * Notify about a clock event change. Called with clockevents_lock - * held. - */ -static void clockevents_do_notify(unsigned long reason, void *dev) -{ - raw_notifier_call_chain(&clockevents_chain, reason, dev); -} - /* * Called after a notify add to make devices available which were * released from the notifier call. @@ -269,7 +240,7 @@ static void clockevents_notify_released(void) struct clock_event_device, list); list_del(&dev->list); list_add(&dev->list, &clockevent_devices); - clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev); + tick_check_new_device(dev); } } @@ -290,7 +261,7 @@ void clockevents_register_device(struct clock_event_device *dev) raw_spin_lock_irqsave(&clockevents_lock, flags); list_add(&dev->list, &clockevent_devices); - clockevents_do_notify(CLOCK_EVT_NOTIFY_ADD, dev); + tick_check_new_device(dev); clockevents_notify_released(); raw_spin_unlock_irqrestore(&clockevents_lock, flags); @@ -433,7 +404,7 @@ void clockevents_notify(unsigned long reason, void *arg) int cpu; raw_spin_lock_irqsave(&clockevents_lock, flags); - clockevents_do_notify(reason, arg); + tick_notify(reason, arg); switch (reason) { case CLOCK_EVT_NOTIFY_CPU_DEAD: diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 24938d577669..3500caaa0bfd 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -64,7 +64,7 @@ static void tick_broadcast_start_periodic(struct clock_event_device *bc) /* * Check, if the device can be utilized as broadcast device: */ -int tick_check_broadcast_device(struct clock_event_device *dev) +void tick_install_broadcast_device(struct clock_event_device *dev) { struct clock_event_device *cur = tick_broadcast_device.evtdev; @@ -72,7 +72,7 @@ int tick_check_broadcast_device(struct clock_event_device *dev) (tick_broadcast_device.evtdev && tick_broadcast_device.evtdev->rating >= dev->rating) || (dev->features & CLOCK_EVT_FEAT_C3STOP)) - return 0; + return; clockevents_exchange_device(tick_broadcast_device.evtdev, dev); if (cur) @@ -90,7 +90,6 @@ int tick_check_broadcast_device(struct clock_event_device *dev) */ if (dev->features & CLOCK_EVT_FEAT_ONESHOT) tick_clock_notify(); - return 1; } /* diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 5d3fb100bc06..dbf4e18d5101 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -208,11 +208,11 @@ static void tick_setup_device(struct tick_device *td, /* * Check, if the new registered device should be used. */ -static int tick_check_new_device(struct clock_event_device *newdev) +void tick_check_new_device(struct clock_event_device *newdev) { struct clock_event_device *curdev; struct tick_device *td; - int cpu, ret = NOTIFY_OK; + int cpu; unsigned long flags; raw_spin_lock_irqsave(&tick_device_lock, flags); @@ -275,18 +275,14 @@ static int tick_check_new_device(struct clock_event_device *newdev) tick_oneshot_notify(); raw_spin_unlock_irqrestore(&tick_device_lock, flags); - return NOTIFY_STOP; + return; out_bc: /* * Can the new device be used as a broadcast device ? */ - if (tick_check_broadcast_device(newdev)) - ret = NOTIFY_STOP; - + tick_install_broadcast_device(newdev); raw_spin_unlock_irqrestore(&tick_device_lock, flags); - - return ret; } /* @@ -360,17 +356,10 @@ static void tick_resume(void) raw_spin_unlock_irqrestore(&tick_device_lock, flags); } -/* - * Notification about clock event devices - */ -static int tick_notify(struct notifier_block *nb, unsigned long reason, - void *dev) +void tick_notify(unsigned long reason, void *dev) { switch (reason) { - case CLOCK_EVT_NOTIFY_ADD: - return tick_check_new_device(dev); - case CLOCK_EVT_NOTIFY_BROADCAST_ON: case CLOCK_EVT_NOTIFY_BROADCAST_OFF: case CLOCK_EVT_NOTIFY_BROADCAST_FORCE: @@ -404,21 +393,12 @@ static int tick_notify(struct notifier_block *nb, unsigned long reason, default: break; } - - return NOTIFY_OK; } -static struct notifier_block tick_notifier = { - .notifier_call = tick_notify, -}; - /** * tick_init - initialize the tick control - * - * Register the notifier with the clockevents framework */ void __init tick_init(void) { - clockevents_register_notifier(&tick_notifier); tick_broadcast_init(); } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index f0299eae4602..60742fe6f63d 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -18,6 +18,8 @@ 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_notify(unsigned long reason, void *dev); +extern void tick_check_new_device(struct clock_event_device *dev); extern void clockevents_shutdown(struct clock_event_device *dev); @@ -90,7 +92,7 @@ static inline bool tick_broadcast_oneshot_available(void) { return false; } */ #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu); -extern int tick_check_broadcast_device(struct clock_event_device *dev); +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_broadcast_on_off(unsigned long reason, int *oncpu); extern void tick_shutdown_broadcast(unsigned int *cpup); @@ -102,9 +104,8 @@ tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); #else /* !BROADCAST */ -static inline int tick_check_broadcast_device(struct clock_event_device *dev) +static inline void tick_install_broadcast_device(struct clock_event_device *dev) { - return 0; } static inline int tick_is_broadcast_device(struct clock_event_device *dev) -- cgit v1.2.3 From ccf33d6880f39a35158fff66db13000ae4943fac Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:49 +0000 Subject: clockevents: Add module refcount We want to be able to remove clockevent modules as well. Add a refcount so we don't remove a module with an active clock event device. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143436.307435149@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clockchips.h | 3 +++ kernel/time/clockevents.c | 1 + kernel/time/tick-broadcast.c | 3 +++ kernel/time/tick-common.c | 4 ++++ 4 files changed, 11 insertions(+) (limited to 'include') diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h index 2f498f66c1bb..ae1193bcf074 100644 --- a/include/linux/clockchips.h +++ b/include/linux/clockchips.h @@ -30,6 +30,7 @@ enum clock_event_nofitiers { #include struct clock_event_device; +struct module; /* Clock event mode commands */ enum clock_event_mode { @@ -83,6 +84,7 @@ enum clock_event_mode { * @irq: IRQ number (only for non CPU local devices) * @cpumask: cpumask to indicate for which CPUs this device works * @list: list head for the management code + * @owner: module reference */ struct clock_event_device { void (*event_handler)(struct clock_event_device *); @@ -112,6 +114,7 @@ struct clock_event_device { int irq; const struct cpumask *cpumask; struct list_head list; + struct module *owner; } ____cacheline_aligned; /* diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 0e3a8448e115..89e394caa769 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -357,6 +357,7 @@ void clockevents_exchange_device(struct clock_event_device *old, * released list and do a notify add later. */ if (old) { + module_put(old->owner); clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED); list_del(&old->list); list_add(&old->list, &clockevents_released); diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 3500caaa0bfd..0e374cd2e0ef 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "tick-internal.h" @@ -73,6 +74,8 @@ void tick_install_broadcast_device(struct clock_event_device *dev) tick_broadcast_device.evtdev->rating >= dev->rating) || (dev->features & CLOCK_EVT_FEAT_C3STOP)) return; + if (!try_module_get(dev->owner)) + return; clockevents_exchange_device(tick_broadcast_device.evtdev, dev); if (cur) diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 84c7cfca4d7d..433a1e11d13b 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -18,6 +18,7 @@ #include #include #include +#include #include @@ -257,6 +258,9 @@ void tick_check_new_device(struct clock_event_device *newdev) goto out_bc; } + if (!try_module_get(newdev->owner)) + return; + /* * Replace the eventually existing device by the new * device. If the current device is the broadcast device, do -- cgit v1.2.3 From 03e13cf5ee60584fe0c831682c67212effb7fca4 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 25 Apr 2013 20:31:50 +0000 Subject: clockevents: Implement unbind functionality Provide a sysfs interface to allow unbinding of clockevent devices. The device is unbound if it is unused or if there is a replacement device available. Unbinding of broadcast devices is not supported as we don't want to foster that nonsense. If no replacement device is available the unbind returns -EBUSY. Unbind is available from the kernel and through sysfs, which is necessary to drop the module refcount. Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Magnus Damm Link: http://lkml.kernel.org/r/20130425143436.499216659@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/clockchips.h | 1 + kernel/time/clockevents.c | 125 ++++++++++++++++++++++++++++++++++++++++++++ kernel/time/clocksource.c | 9 ++-- kernel/time/tick-common.c | 24 +++++++++ kernel/time/tick-internal.h | 7 +++ 5 files changed, 162 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h index ae1193bcf074..0857922e8ad0 100644 --- a/include/linux/clockchips.h +++ b/include/linux/clockchips.h @@ -141,6 +141,7 @@ static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec, extern u64 clockevent_delta2ns(unsigned long latch, struct clock_event_device *evt); extern void clockevents_register_device(struct clock_event_device *dev); +extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu); extern void clockevents_config(struct clock_event_device *dev, u32 freq); extern void clockevents_config_and_register(struct clock_event_device *dev, diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 0a23f4f29934..38959c866789 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -25,6 +25,13 @@ static LIST_HEAD(clockevent_devices); static LIST_HEAD(clockevents_released); /* Protection for the above */ static DEFINE_RAW_SPINLOCK(clockevents_lock); +/* Protection for unbind operations */ +static DEFINE_MUTEX(clockevents_mutex); + +struct ce_unbind { + struct clock_event_device *ce; + int res; +}; /** * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds @@ -245,6 +252,90 @@ static void clockevents_notify_released(void) } } +/* + * Try to install a replacement clock event device + */ +static int clockevents_replace(struct clock_event_device *ced) +{ + struct clock_event_device *dev, *newdev = NULL; + + list_for_each_entry(dev, &clockevent_devices, list) { + if (dev == ced || dev->mode != CLOCK_EVT_MODE_UNUSED) + continue; + + if (!tick_check_replacement(newdev, dev)) + continue; + + if (!try_module_get(dev->owner)) + continue; + + if (newdev) + module_put(newdev->owner); + newdev = dev; + } + if (newdev) { + tick_install_replacement(newdev); + list_del_init(&ced->list); + } + return newdev ? 0 : -EBUSY; +} + +/* + * Called with clockevents_mutex and clockevents_lock held + */ +static int __clockevents_try_unbind(struct clock_event_device *ced, int cpu) +{ + /* Fast track. Device is unused */ + if (ced->mode == CLOCK_EVT_MODE_UNUSED) { + list_del_init(&ced->list); + return 0; + } + + return ced == per_cpu(tick_cpu_device, cpu).evtdev ? -EAGAIN : -EBUSY; +} + +/* + * SMP function call to unbind a device + */ +static void __clockevents_unbind(void *arg) +{ + struct ce_unbind *cu = arg; + int res; + + raw_spin_lock(&clockevents_lock); + res = __clockevents_try_unbind(cu->ce, smp_processor_id()); + if (res == -EAGAIN) + res = clockevents_replace(cu->ce); + cu->res = res; + raw_spin_unlock(&clockevents_lock); +} + +/* + * Issues smp function call to unbind a per cpu device. Called with + * clockevents_mutex held. + */ +static int clockevents_unbind(struct clock_event_device *ced, int cpu) +{ + struct ce_unbind cu = { .ce = ced, .res = -ENODEV }; + + smp_call_function_single(cpu, __clockevents_unbind, &cu, 1); + return cu.res; +} + +/* + * Unbind a clockevents device. + */ +int clockevents_unbind_device(struct clock_event_device *ced, int cpu) +{ + int ret; + + mutex_lock(&clockevents_mutex); + ret = clockevents_unbind(ced, cpu); + mutex_unlock(&clockevents_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(clockevents_unbind); + /** * clockevents_register_device - register a clock event device * @dev: device to register @@ -487,6 +578,38 @@ static ssize_t sysfs_show_current_tick_dev(struct device *dev, } static DEVICE_ATTR(current_device, 0444, sysfs_show_current_tick_dev, NULL); +/* We don't support the abomination of removable broadcast devices */ +static ssize_t sysfs_unbind_tick_dev(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + char name[CS_NAME_LEN]; + size_t ret = sysfs_get_uname(buf, name, count); + struct clock_event_device *ce; + + if (ret < 0) + return ret; + + ret = -ENODEV; + mutex_lock(&clockevents_mutex); + raw_spin_lock_irq(&clockevents_lock); + list_for_each_entry(ce, &clockevent_devices, list) { + if (!strcmp(ce->name, name)) { + ret = __clockevents_try_unbind(ce, dev->id); + break; + } + } + raw_spin_unlock_irq(&clockevents_lock); + /* + * We hold clockevents_mutex, so ce can't go away + */ + if (ret == -EAGAIN) + ret = clockevents_unbind(ce, dev->id); + mutex_unlock(&clockevents_mutex); + return ret ? ret : count; +} +static DEVICE_ATTR(unbind_device, 0200, NULL, sysfs_unbind_tick_dev); + #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST static struct device tick_bc_dev = { .init_name = "broadcast", @@ -529,6 +652,8 @@ static int __init tick_init_sysfs(void) err = device_register(dev); if (!err) err = device_create_file(dev, &dev_attr_current_device); + if (!err) + err = device_create_file(dev, &dev_attr_unbind_device); if (err) return err; } diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 31b90332f47b..6d05b00410cc 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -31,6 +31,8 @@ #include #include +#include "tick-internal.h" + void timecounter_init(struct timecounter *tc, const struct cyclecounter *cc, u64 start_tstamp) @@ -174,7 +176,6 @@ clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 maxsec) static struct clocksource *curr_clocksource; static LIST_HEAD(clocksource_list); static DEFINE_MUTEX(clocksource_mutex); -#define CS_NAME_LEN 32 static char override_name[CS_NAME_LEN]; static int finished_booting; @@ -864,7 +865,7 @@ sysfs_show_current_clocksources(struct device *dev, return count; } -static size_t clocksource_get_uname(const char *buf, char *dst, size_t cnt) +size_t sysfs_get_uname(const char *buf, char *dst, size_t cnt) { size_t ret = cnt; @@ -899,7 +900,7 @@ static ssize_t sysfs_override_clocksource(struct device *dev, mutex_lock(&clocksource_mutex); - ret = clocksource_get_uname(buf, override_name, count); + ret = sysfs_get_uname(buf, override_name, count); if (ret >= 0) clocksource_select(); @@ -925,7 +926,7 @@ static ssize_t sysfs_unbind_clocksource(struct device *dev, char name[CS_NAME_LEN]; size_t ret; - ret = clocksource_get_uname(buf, name, count); + ret = sysfs_get_uname(buf, name, count); if (ret < 0) return ret; diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index c34021650348..5edfb4806032 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -205,6 +205,17 @@ static void tick_setup_device(struct tick_device *td, tick_setup_oneshot(newdev, handler, next_event); } +void tick_install_replacement(struct clock_event_device *newdev) +{ + struct tick_device *td = &__get_cpu_var(tick_cpu_device); + int cpu = smp_processor_id(); + + clockevents_exchange_device(td->evtdev, newdev); + tick_setup_device(td, newdev, cpu, cpumask_of(cpu)); + if (newdev->features & CLOCK_EVT_FEAT_ONESHOT) + tick_oneshot_notify(); +} + static bool tick_check_percpu(struct clock_event_device *curdev, struct clock_event_device *newdev, int cpu) { @@ -236,6 +247,19 @@ static bool tick_check_preferred(struct clock_event_device *curdev, return !curdev || newdev->rating > curdev->rating; } +/* + * Check whether the new device is a better fit than curdev. curdev + * can be NULL ! + */ +bool tick_check_replacement(struct clock_event_device *curdev, + struct clock_event_device *newdev) +{ + if (tick_check_percpu(curdev, newdev, smp_processor_id())) + return false; + + return tick_check_preferred(curdev, newdev); +} + /* * Check, if the new registered device should be used. Called with * clockevents_lock held and interrupts disabled. diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 06bfc8802dfb..be1690eaecff 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -11,6 +11,8 @@ extern seqlock_t jiffies_lock; #define TICK_DO_TIMER_NONE -1 #define TICK_DO_TIMER_BOOT -2 +#define CS_NAME_LEN 32 + DECLARE_PER_CPU(struct tick_device, tick_cpu_device); extern ktime_t tick_next_period; extern ktime_t tick_period; @@ -23,9 +25,14 @@ extern void tick_handover_do_timer(int *cpup); extern void tick_shutdown(unsigned int *cpup); extern void tick_suspend(void); extern void tick_resume(void); +extern bool tick_check_replacement(struct clock_event_device *curdev, + struct clock_event_device *newdev); +extern void tick_install_replacement(struct clock_event_device *dev); extern void clockevents_shutdown(struct clock_event_device *dev); +extern size_t sysfs_get_uname(const char *buf, char *dst, size_t cnt); + /* * NO_HZ / high resolution timer shared code */ -- cgit v1.2.3 From a44b8bd6072ac82fc49af941de8c1ac85d94852d Mon Sep 17 00:00:00 2001 From: Liu Ying Date: Tue, 7 May 2013 16:38:40 +0800 Subject: ktime: Use macro NSEC_PER_USEC where appropriate We've got the macro NSEC_PER_USEC defined in header file include/linux/time.h. To make the code decent, this patch replaces the immediate number 1000 to convert bewteen a time value in microseconds and one in nanoseconds with the macro NSEC_PER_USEC. Signed-off-by: Liu Ying Cc: David S. Miller Cc: Daniel Borkmann Cc: Thomas Gleixner Cc: John Stultz Signed-off-by: John Stultz --- include/linux/ktime.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/ktime.h b/include/linux/ktime.h index bbca12804d12..608728a164a9 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -229,7 +229,8 @@ static inline ktime_t timespec_to_ktime(const struct timespec ts) static inline ktime_t timeval_to_ktime(const struct timeval tv) { return (ktime_t) { .tv = { .sec = (s32)tv.tv_sec, - .nsec = (s32)tv.tv_usec * 1000 } }; + .nsec = (s32)(tv.tv_usec * + NSEC_PER_USEC) } }; } /** @@ -320,12 +321,12 @@ static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier) static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) { - return ktime_add_ns(kt, usec * 1000); + return ktime_add_ns(kt, usec * NSEC_PER_USEC); } static inline ktime_t ktime_sub_us(const ktime_t kt, const u64 usec) { - return ktime_sub_ns(kt, usec * 1000); + return ktime_sub_ns(kt, usec * NSEC_PER_USEC); } extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); -- cgit v1.2.3 From 35b210855069ae34450eeaafc0f1b5bfa4f71c87 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 16 May 2013 15:47:49 +0200 Subject: ktime: Add __must_check prefix to ktime_to_timespec_cond The function is currently mainly used in the networking code and if others start using it, they must check the result, otherwise it cannot be determined if the timespec conversion suceeded. Currently no user lacks this check, but make future users aware of a possible misusage. Signed-off-by: Daniel Borkmann Signed-off-by: John Stultz --- include/linux/ktime.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/ktime.h b/include/linux/ktime.h index 608728a164a9..fc66b301b648 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -339,7 +339,8 @@ extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs); * * Returns true if there was a successful conversion, false if kt was 0. */ -static inline bool ktime_to_timespec_cond(const ktime_t kt, struct timespec *ts) +static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt, + struct timespec *ts) { if (kt.tv64) { *ts = ktime_to_timespec(kt); -- cgit v1.2.3 From 55a68c23e0a675b2b8ac2656fd6edbf98b78e4c6 Mon Sep 17 00:00:00 2001 From: Pavel Machek Date: Tue, 7 May 2013 22:11:26 +0200 Subject: dw_apb_timer_of.c: Remove parts that were picoxcell-specific It seems we made a mistake when creating dw_apb_timer_of.c: picoxcell sched_clock had parts that were not related to dw_apb_timer, yet we moved them to dw_apb_timer_of, and tried to use them on socfpga. This results in system where user/system time is not measured properly, as demonstrated by time dd if=/dev/urandom of=/dev/zero bs=100000 count=100 So this patch switches sched_clock to hardware that exists on both platforms, and adds missing of_node_put() in dw_apb_timer_init(). Signed-off-by: Pavel Machek Acked-by: Jamie Iles Signed-off-by: John Stultz --- arch/arm/mach-picoxcell/common.h | 2 -- drivers/clocksource/dw_apb_timer.c | 6 ---- drivers/clocksource/dw_apb_timer_of.c | 52 ++++++++++++++++------------------- include/linux/dw_apb_timer.h | 6 ++++ 4 files changed, 29 insertions(+), 37 deletions(-) (limited to 'include') diff --git a/arch/arm/mach-picoxcell/common.h b/arch/arm/mach-picoxcell/common.h index 481b42a4ef15..237fb3bcbd04 100644 --- a/arch/arm/mach-picoxcell/common.h +++ b/arch/arm/mach-picoxcell/common.h @@ -12,6 +12,4 @@ #include -extern void dw_apb_timer_init(void); - #endif /* __PICOXCELL_COMMON_H__ */ diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c index e54ca1062d8e..e7042bc5c7d2 100644 --- a/drivers/clocksource/dw_apb_timer.c +++ b/drivers/clocksource/dw_apb_timer.c @@ -21,12 +21,6 @@ #define APBT_MIN_PERIOD 4 #define APBT_MIN_DELTA_USEC 200 -#define APBTMR_N_LOAD_COUNT 0x00 -#define APBTMR_N_CURRENT_VALUE 0x04 -#define APBTMR_N_CONTROL 0x08 -#define APBTMR_N_EOI 0x0c -#define APBTMR_N_INT_STATUS 0x10 - #define APBTMRS_INT_STATUS 0xa0 #define APBTMRS_EOI 0xa4 #define APBTMRS_RAW_INT_STATUS 0xa8 diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index ab09ed3742ee..44a3b9163c46 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -57,6 +57,15 @@ static void add_clockevent(struct device_node *event_timer) dw_apb_clockevent_register(ced); } +static void __iomem *sched_io_base; + +/* This is actually same as __apbt_read_clocksource(), but with + different interface */ +static u32 read_sched_clock_sptimer(void) +{ + return ~__raw_readl(sched_io_base + APBTMR_N_CURRENT_VALUE); +} + static void add_clocksource(struct device_node *source_timer) { void __iomem *iobase; @@ -71,41 +80,27 @@ static void add_clocksource(struct device_node *source_timer) dw_apb_clocksource_start(cs); dw_apb_clocksource_register(cs); -} -static void __iomem *sched_io_base; - -static u32 read_sched_clock(void) -{ - return __raw_readl(sched_io_base); + sched_io_base = iobase; + setup_sched_clock(read_sched_clock_sptimer, 32, rate); } -static const struct of_device_id sptimer_ids[] __initconst = { - { .compatible = "picochip,pc3x2-rtc" }, +static const struct of_device_id osctimer_ids[] __initconst = { + { .compatible = "picochip,pc3x2-timer" }, + { .compatible = "snps,dw-apb-timer-osc" }, { .compatible = "snps,dw-apb-timer-sp" }, - { /* Sentinel */ }, + { /* Sentinel */ }, }; -static void init_sched_clock(void) -{ - struct device_node *sched_timer; - u32 rate; - - sched_timer = of_find_matching_node(NULL, sptimer_ids); - if (!sched_timer) - panic("No RTC for sched clock to use"); +/* + You don't have to use dw_apb_timer for scheduler clock, + this should also work fine on arm: - timer_get_base_and_rate(sched_timer, &sched_io_base, &rate); - of_node_put(sched_timer); + twd_local_timer_of_register(); + arch_timer_of_register(); + arch_timer_sched_clock_init(); +*/ - setup_sched_clock(read_sched_clock, 32, rate); -} - -static const struct of_device_id osctimer_ids[] __initconst = { - { .compatible = "picochip,pc3x2-timer" }, - { .compatible = "snps,dw-apb-timer-osc" }, - {}, -}; void __init dw_apb_timer_init(void) { @@ -121,7 +116,6 @@ void __init dw_apb_timer_init(void) panic("No timer for clocksource"); add_clocksource(source_timer); + of_node_put(event_timer); of_node_put(source_timer); - - init_sched_clock(); } diff --git a/include/linux/dw_apb_timer.h b/include/linux/dw_apb_timer.h index b1cd9597c241..de0904e38f33 100644 --- a/include/linux/dw_apb_timer.h +++ b/include/linux/dw_apb_timer.h @@ -17,6 +17,12 @@ #include #include +#define APBTMR_N_LOAD_COUNT 0x00 +#define APBTMR_N_CURRENT_VALUE 0x04 +#define APBTMR_N_CONTROL 0x08 +#define APBTMR_N_EOI 0x0c +#define APBTMR_N_INT_STATUS 0x10 + #define APBTMRS_REG_SIZE 0x14 struct dw_apb_timer { -- cgit v1.2.3 From 3565184ed0c1ea46bea5b792da5f72a83c43e49b Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Mon, 13 May 2013 18:56:06 +0100 Subject: x86: Increase precision of x86_platform.get/set_wallclock() All the virtualized platforms (KVM, lguest and Xen) have persistent wallclocks that have more than one second of precision. read_persistent_wallclock() and update_persistent_wallclock() allow for nanosecond precision but their implementation on x86 with x86_platform.get/set_wallclock() only allows for one second precision. This means guests may see a wallclock time that is off by up to 1 second. Make set_wallclock() and get_wallclock() take a struct timespec parameter (which allows for nanosecond precision) so KVM and Xen guests may start with a more accurate wallclock time and a Xen dom0 can maintain a more accurate wallclock for guests. Signed-off-by: David Vrabel Signed-off-by: John Stultz --- arch/x86/include/asm/mc146818rtc.h | 4 ++-- arch/x86/include/asm/x86_init.h | 6 ++++-- arch/x86/kernel/kvmclock.c | 9 +++------ arch/x86/kernel/rtc.c | 17 +++++++---------- arch/x86/lguest/boot.c | 4 ++-- arch/x86/platform/efi/efi.c | 10 ++++++---- arch/x86/xen/time.c | 19 ++++++------------- include/linux/efi.h | 4 ++-- 8 files changed, 32 insertions(+), 41 deletions(-) (limited to 'include') diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h index d354fb781c57..a55c7efcc4ed 100644 --- a/arch/x86/include/asm/mc146818rtc.h +++ b/arch/x86/include/asm/mc146818rtc.h @@ -95,8 +95,8 @@ static inline unsigned char current_lock_cmos_reg(void) unsigned char rtc_cmos_read(unsigned char addr); void rtc_cmos_write(unsigned char val, unsigned char addr); -extern int mach_set_rtc_mmss(unsigned long nowtime); -extern unsigned long mach_get_cmos_time(void); +extern int mach_set_rtc_mmss(const struct timespec *now); +extern void mach_get_cmos_time(struct timespec *now); #define RTC_IRQ 8 diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index d8d99222b36a..828a1565ba57 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -142,6 +142,8 @@ struct x86_cpuinit_ops { void (*fixup_cpu_id)(struct cpuinfo_x86 *c, int node); }; +struct timespec; + /** * struct x86_platform_ops - platform specific runtime functions * @calibrate_tsc: calibrate TSC @@ -156,8 +158,8 @@ struct x86_cpuinit_ops { */ struct x86_platform_ops { unsigned long (*calibrate_tsc)(void); - unsigned long (*get_wallclock)(void); - int (*set_wallclock)(unsigned long nowtime); + void (*get_wallclock)(struct timespec *ts); + int (*set_wallclock)(const struct timespec *ts); void (*iommu_shutdown)(void); bool (*is_untracked_pat_range)(u64 start, u64 end); void (*nmi_init)(void); diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index d2c381280e3c..0db81ab511cc 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -48,10 +48,9 @@ static struct pvclock_wall_clock wall_clock; * have elapsed since the hypervisor wrote the data. So we try to account for * that with system time */ -static unsigned long kvm_get_wallclock(void) +static void kvm_get_wallclock(struct timespec *now) { struct pvclock_vcpu_time_info *vcpu_time; - struct timespec ts; int low, high; int cpu; @@ -64,14 +63,12 @@ static unsigned long kvm_get_wallclock(void) cpu = smp_processor_id(); vcpu_time = &hv_clock[cpu].pvti; - pvclock_read_wallclock(&wall_clock, vcpu_time, &ts); + pvclock_read_wallclock(&wall_clock, vcpu_time, now); preempt_enable(); - - return ts.tv_sec; } -static int kvm_set_wallclock(unsigned long now) +static int kvm_set_wallclock(const struct timespec *now) { return -1; } diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c index 198eb201ed3b..0aa29394ed6f 100644 --- a/arch/x86/kernel/rtc.c +++ b/arch/x86/kernel/rtc.c @@ -38,8 +38,9 @@ EXPORT_SYMBOL(rtc_lock); * jump to the next second precisely 500 ms later. Check the Motorola * MC146818A or Dallas DS12887 data sheet for details. */ -int mach_set_rtc_mmss(unsigned long nowtime) +int mach_set_rtc_mmss(const struct timespec *now) { + unsigned long nowtime = now->tv_sec; struct rtc_time tm; int retval = 0; @@ -58,7 +59,7 @@ int mach_set_rtc_mmss(unsigned long nowtime) return retval; } -unsigned long mach_get_cmos_time(void) +void mach_get_cmos_time(struct timespec *now) { unsigned int status, year, mon, day, hour, min, sec, century = 0; unsigned long flags; @@ -107,7 +108,8 @@ unsigned long mach_get_cmos_time(void) } else year += CMOS_YEARS_OFFS; - return mktime(year, mon, day, hour, min, sec); + now->tv_sec = mktime(year, mon, day, hour, min, sec); + now->tv_nsec = 0; } /* Routines for accessing the CMOS RAM/RTC. */ @@ -135,18 +137,13 @@ EXPORT_SYMBOL(rtc_cmos_write); int update_persistent_clock(struct timespec now) { - return x86_platform.set_wallclock(now.tv_sec); + return x86_platform.set_wallclock(&now); } /* not static: needed by APM */ void read_persistent_clock(struct timespec *ts) { - unsigned long retval; - - retval = x86_platform.get_wallclock(); - - ts->tv_sec = retval; - ts->tv_nsec = 0; + x86_platform.get_wallclock(ts); } diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 7114c63f047d..8424d5adcfa2 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -882,9 +882,9 @@ int lguest_setup_irq(unsigned int irq) * It would be far better for everyone if the Guest had its own clock, but * until then the Host gives us the time on every interrupt. */ -static unsigned long lguest_get_wallclock(void) +static void lguest_get_wallclock(struct timespec *now) { - return lguest_data.time.tv_sec; + *now = lguest_data.time; } /* diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 55856b2310d3..dd3b82530145 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -352,8 +352,9 @@ static efi_status_t __init phys_efi_get_time(efi_time_t *tm, return status; } -int efi_set_rtc_mmss(unsigned long nowtime) +int efi_set_rtc_mmss(const struct timespec *now) { + unsigned long nowtime = now->tv_sec; efi_status_t status; efi_time_t eft; efi_time_cap_t cap; @@ -388,7 +389,7 @@ int efi_set_rtc_mmss(unsigned long nowtime) return 0; } -unsigned long efi_get_time(void) +void efi_get_time(struct timespec *now) { efi_status_t status; efi_time_t eft; @@ -398,8 +399,9 @@ unsigned long efi_get_time(void) if (status != EFI_SUCCESS) pr_err("Oops: efitime: can't read time!\n"); - return mktime(eft.year, eft.month, eft.day, eft.hour, - eft.minute, eft.second); + now->tv_sec = mktime(eft.year, eft.month, eft.day, eft.hour, + eft.minute, eft.second); + now->tv_nsec = 0; } /* diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 3d88bfdf9e1c..a1947ac2da82 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -191,32 +191,25 @@ static void xen_read_wallclock(struct timespec *ts) put_cpu_var(xen_vcpu); } -static unsigned long xen_get_wallclock(void) +static void xen_get_wallclock(struct timespec *now) { - struct timespec ts; - - xen_read_wallclock(&ts); - return ts.tv_sec; + xen_read_wallclock(now); } -static int xen_set_wallclock(unsigned long now) +static int xen_set_wallclock(const struct timespec *now) { struct xen_platform_op op; - int rc; /* do nothing for domU */ if (!xen_initial_domain()) return -1; op.cmd = XENPF_settime; - op.u.settime.secs = now; - op.u.settime.nsecs = 0; + op.u.settime.secs = now->tv_sec; + op.u.settime.nsecs = now->tv_nsec; op.u.settime.system_time = xen_clocksource_read(); - rc = HYPERVISOR_dom0_op(&op); - WARN(rc != 0, "XENPF_settime failed: now=%ld\n", now); - - return rc; + return HYPERVISOR_dom0_op(&op); } static struct clocksource xen_clocksource __read_mostly = { diff --git a/include/linux/efi.h b/include/linux/efi.h index 2bc0ad78d058..0068bba6f8b6 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -594,8 +594,8 @@ extern u64 efi_mem_attribute (unsigned long phys_addr, unsigned long size); extern int __init efi_uart_console_only (void); extern void efi_initialize_iomem_resources(struct resource *code_resource, struct resource *data_resource, struct resource *bss_resource); -extern unsigned long efi_get_time(void); -extern int efi_set_rtc_mmss(unsigned long nowtime); +extern void efi_get_time(struct timespec *now); +extern int efi_set_rtc_mmss(const struct timespec *now); extern void efi_reserve_boot_services(void); extern struct efi_memory_map memmap; -- cgit v1.2.3 From 6cffe00f7d4e24679eae6b7aae4caaf915288256 Mon Sep 17 00:00:00 2001 From: Todd Poynor Date: Wed, 15 May 2013 14:38:11 -0700 Subject: alarmtimer: Add functions for timerfd support Add functions needed for hooking up alarmtimer to timerfd: * alarm_restart: Similar to hrtimer_restart, restart an alarmtimer after the expires time has already been updated (as with alarm_forward). * alarm_forward_now: Similar to hrtimer_forward_now, move the expires time forward to an interval from the current time of the associated clock. * alarm_start_relative: Start an alarmtimer with an expires time relative to the current time of the associated clock. * alarm_expires_remaining: Similar to hrtimer_expires_remaining, return the amount of time remaining until alarm expiry. Signed-off-by: Todd Poynor Signed-off-by: John Stultz --- include/linux/alarmtimer.h | 4 ++++ kernel/time/alarmtimer.c | 39 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 42 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/alarmtimer.h b/include/linux/alarmtimer.h index 9069694e70eb..a899402a5a0e 100644 --- a/include/linux/alarmtimer.h +++ b/include/linux/alarmtimer.h @@ -44,10 +44,14 @@ struct alarm { void alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)); int alarm_start(struct alarm *alarm, ktime_t start); +int alarm_start_relative(struct alarm *alarm, ktime_t start); +void alarm_restart(struct alarm *alarm); int alarm_try_to_cancel(struct alarm *alarm); int alarm_cancel(struct alarm *alarm); u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval); +u64 alarm_forward_now(struct alarm *alarm, ktime_t interval); +ktime_t alarm_expires_remaining(const struct alarm *alarm); /* Provide way to access the rtc device being used by alarmtimers */ struct rtc_device *alarmtimer_get_rtcdev(void); diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index f11d83b12949..3e5cba274475 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -199,6 +199,12 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) } +ktime_t alarm_expires_remaining(const struct alarm *alarm) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + return ktime_sub(alarm->node.expires, base->gettime()); +} + #ifdef CONFIG_RTC_CLASS /** * alarmtimer_suspend - Suspend time callback @@ -305,7 +311,7 @@ void alarm_init(struct alarm *alarm, enum alarmtimer_type type, } /** - * alarm_start - Sets an alarm to fire + * alarm_start - Sets an absolute alarm to fire * @alarm: ptr to alarm to set * @start: time to run the alarm */ @@ -324,6 +330,31 @@ int alarm_start(struct alarm *alarm, ktime_t start) return ret; } +/** + * alarm_start_relative - Sets a relative alarm to fire + * @alarm: ptr to alarm to set + * @start: time relative to now to run the alarm + */ +int alarm_start_relative(struct alarm *alarm, ktime_t start) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + + start = ktime_add(start, base->gettime()); + return alarm_start(alarm, start); +} + +void alarm_restart(struct alarm *alarm) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + unsigned long flags; + + spin_lock_irqsave(&base->lock, flags); + hrtimer_set_expires(&alarm->timer, alarm->node.expires); + hrtimer_restart(&alarm->timer); + alarmtimer_enqueue(base, alarm); + spin_unlock_irqrestore(&base->lock, flags); +} + /** * alarm_try_to_cancel - Tries to cancel an alarm timer * @alarm: ptr to alarm to be canceled @@ -394,6 +425,12 @@ u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) return overrun; } +u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) +{ + struct alarm_base *base = &alarm_bases[alarm->type]; + + return alarm_forward(alarm, base->gettime(), interval); +} -- cgit v1.2.3 From 38ff87f77af0b5a93fc8581cff1d6e5692ab8970 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Sat, 1 Jun 2013 23:39:40 -0700 Subject: sched_clock: Make ARM's sched_clock generic for all architectures Nothing about the sched_clock implementation in the ARM port is specific to the architecture. Generalize the code so that other architectures can use it by selecting GENERIC_SCHED_CLOCK. Signed-off-by: Stephen Boyd [jstultz: Merge minor collisions with other patches in my tree] Signed-off-by: John Stultz --- arch/arm/Kconfig | 1 + arch/arm/common/timer-sp.c | 2 +- arch/arm/include/asm/sched_clock.h | 16 --- arch/arm/kernel/Makefile | 2 +- arch/arm/kernel/arch_timer.c | 2 +- arch/arm/kernel/sched_clock.c | 216 ------------------------------ arch/arm/kernel/time.c | 4 +- arch/arm/mach-davinci/time.c | 2 +- arch/arm/mach-imx/time.c | 2 +- arch/arm/mach-integrator/integrator_ap.c | 2 +- arch/arm/mach-ixp4xx/common.c | 2 +- arch/arm/mach-mmp/time.c | 2 +- arch/arm/mach-msm/timer.c | 2 +- arch/arm/mach-omap1/time.c | 2 +- arch/arm/mach-omap2/timer.c | 2 +- arch/arm/mach-pxa/time.c | 2 +- arch/arm/mach-sa1100/time.c | 2 +- arch/arm/mach-u300/timer.c | 2 +- arch/arm/plat-iop/time.c | 2 +- arch/arm/plat-omap/counter_32k.c | 2 +- arch/arm/plat-orion/time.c | 2 +- arch/arm/plat-samsung/samsung-time.c | 2 +- arch/arm/plat-versatile/sched-clock.c | 2 +- drivers/clocksource/bcm2835_timer.c | 2 +- drivers/clocksource/clksrc-dbx500-prcmu.c | 3 +- drivers/clocksource/dw_apb_timer_of.c | 3 +- drivers/clocksource/mxs_timer.c | 2 +- drivers/clocksource/nomadik-mtu.c | 2 +- drivers/clocksource/samsung_pwm_timer.c | 2 +- drivers/clocksource/tegra20_timer.c | 2 +- drivers/clocksource/time-armada-370-xp.c | 2 +- drivers/clocksource/timer-marco.c | 2 +- drivers/clocksource/timer-prima2.c | 2 +- include/linux/sched_clock.h | 21 +++ init/Kconfig | 3 + init/main.c | 2 + kernel/time/Makefile | 1 + kernel/time/sched_clock.c | 215 +++++++++++++++++++++++++++++ 38 files changed, 273 insertions(+), 266 deletions(-) delete mode 100644 arch/arm/include/asm/sched_clock.h delete mode 100644 arch/arm/kernel/sched_clock.c create mode 100644 include/linux/sched_clock.h create mode 100644 kernel/time/sched_clock.c (limited to 'include') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 49d993cee512..53d3a356f61f 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -14,6 +14,7 @@ config ARM select GENERIC_IRQ_PROBE select GENERIC_IRQ_SHOW select GENERIC_PCI_IOMAP + select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select GENERIC_IDLE_POLL_SETUP select GENERIC_STRNCPY_FROM_USER diff --git a/arch/arm/common/timer-sp.c b/arch/arm/common/timer-sp.c index ddc740769601..023ee63827a2 100644 --- a/arch/arm/common/timer-sp.c +++ b/arch/arm/common/timer-sp.c @@ -28,8 +28,8 @@ #include #include #include +#include -#include #include #include diff --git a/arch/arm/include/asm/sched_clock.h b/arch/arm/include/asm/sched_clock.h deleted file mode 100644 index 3d520ddca61b..000000000000 --- a/arch/arm/include/asm/sched_clock.h +++ /dev/null @@ -1,16 +0,0 @@ -/* - * sched_clock.h: support for extending counters to full 64-bit ns counter - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#ifndef ASM_SCHED_CLOCK -#define ASM_SCHED_CLOCK - -extern void sched_clock_postinit(void); -extern void setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate); - -extern unsigned long long (*sched_clock_func)(void); - -#endif diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 5f3338eacad2..97cb0576d07c 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -16,7 +16,7 @@ CFLAGS_REMOVE_return_address.o = -pg # Object file lists. obj-y := elf.o entry-armv.o entry-common.o irq.o opcodes.o \ - process.o ptrace.o return_address.o sched_clock.o \ + process.o ptrace.o return_address.o \ setup.o signal.o stacktrace.o sys_arm.o time.o traps.o obj-$(CONFIG_ATAGS) += atags_parse.o diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c index 59dcdced6e30..221f07b11ccb 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -11,9 +11,9 @@ #include #include #include +#include #include -#include #include diff --git a/arch/arm/kernel/sched_clock.c b/arch/arm/kernel/sched_clock.c deleted file mode 100644 index a781c59b93c0..000000000000 --- a/arch/arm/kernel/sched_clock.c +++ /dev/null @@ -1,216 +0,0 @@ -/* - * sched_clock.c: support for extending counters to full 64-bit ns counter - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -struct clock_data { - u64 epoch_ns; - u32 epoch_cyc; - u32 epoch_cyc_copy; - unsigned long rate; - u32 mult; - u32 shift; - bool suspended; -}; - -static void sched_clock_poll(unsigned long wrap_ticks); -static DEFINE_TIMER(sched_clock_timer, sched_clock_poll, 0, 0); -static int irqtime = -1; - -core_param(irqtime, irqtime, int, 0400); - -static struct clock_data cd = { - .mult = NSEC_PER_SEC / HZ, -}; - -static u32 __read_mostly sched_clock_mask = 0xffffffff; - -static u32 notrace jiffy_sched_clock_read(void) -{ - return (u32)(jiffies - INITIAL_JIFFIES); -} - -static u32 __read_mostly (*read_sched_clock)(void) = jiffy_sched_clock_read; - -static inline u64 notrace cyc_to_ns(u64 cyc, u32 mult, u32 shift) -{ - return (cyc * mult) >> shift; -} - -static unsigned long long notrace cyc_to_sched_clock(u32 cyc, u32 mask) -{ - u64 epoch_ns; - u32 epoch_cyc; - - /* - * Load the epoch_cyc and epoch_ns atomically. We do this by - * ensuring that we always write epoch_cyc, epoch_ns and - * epoch_cyc_copy in strict order, and read them in strict order. - * If epoch_cyc and epoch_cyc_copy are not equal, then we're in - * the middle of an update, and we should repeat the load. - */ - do { - epoch_cyc = cd.epoch_cyc; - smp_rmb(); - epoch_ns = cd.epoch_ns; - smp_rmb(); - } while (epoch_cyc != cd.epoch_cyc_copy); - - return epoch_ns + cyc_to_ns((cyc - epoch_cyc) & mask, cd.mult, cd.shift); -} - -/* - * Atomically update the sched_clock epoch. - */ -static void notrace update_sched_clock(void) -{ - unsigned long flags; - u32 cyc; - u64 ns; - - cyc = read_sched_clock(); - ns = cd.epoch_ns + - cyc_to_ns((cyc - cd.epoch_cyc) & sched_clock_mask, - cd.mult, cd.shift); - /* - * Write epoch_cyc and epoch_ns in a way that the update is - * detectable in cyc_to_fixed_sched_clock(). - */ - raw_local_irq_save(flags); - cd.epoch_cyc_copy = cyc; - smp_wmb(); - cd.epoch_ns = ns; - smp_wmb(); - cd.epoch_cyc = cyc; - raw_local_irq_restore(flags); -} - -static void sched_clock_poll(unsigned long wrap_ticks) -{ - mod_timer(&sched_clock_timer, round_jiffies(jiffies + wrap_ticks)); - update_sched_clock(); -} - -void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate) -{ - unsigned long r, w; - u64 res, wrap; - char r_unit; - - if (cd.rate > rate) - return; - - BUG_ON(bits > 32); - WARN_ON(!irqs_disabled()); - read_sched_clock = read; - sched_clock_mask = (1 << bits) - 1; - cd.rate = rate; - - /* calculate the mult/shift to convert counter ticks to ns. */ - clocks_calc_mult_shift(&cd.mult, &cd.shift, rate, NSEC_PER_SEC, 0); - - r = rate; - if (r >= 4000000) { - r /= 1000000; - r_unit = 'M'; - } else if (r >= 1000) { - r /= 1000; - r_unit = 'k'; - } else - r_unit = ' '; - - /* calculate how many ns until we wrap */ - wrap = cyc_to_ns((1ULL << bits) - 1, cd.mult, cd.shift); - do_div(wrap, NSEC_PER_MSEC); - w = wrap; - - /* calculate the ns resolution of this counter */ - res = cyc_to_ns(1ULL, cd.mult, cd.shift); - pr_info("sched_clock: %u bits at %lu%cHz, resolution %lluns, wraps every %lums\n", - bits, r, r_unit, res, w); - - /* - * Start the timer to keep sched_clock() properly updated and - * sets the initial epoch. - */ - sched_clock_timer.data = msecs_to_jiffies(w - (w / 10)); - update_sched_clock(); - - /* - * Ensure that sched_clock() starts off at 0ns - */ - cd.epoch_ns = 0; - - /* Enable IRQ time accounting if we have a fast enough sched_clock */ - if (irqtime > 0 || (irqtime == -1 && rate >= 1000000)) - enable_sched_clock_irqtime(); - - pr_debug("Registered %pF as sched_clock source\n", read); -} - -static unsigned long long notrace sched_clock_32(void) -{ - u32 cyc = read_sched_clock(); - return cyc_to_sched_clock(cyc, sched_clock_mask); -} - -unsigned long long __read_mostly (*sched_clock_func)(void) = sched_clock_32; - -unsigned long long notrace sched_clock(void) -{ - if (cd.suspended) - return cd.epoch_ns; - - return sched_clock_func(); -} - -void __init sched_clock_postinit(void) -{ - /* - * If no sched_clock function has been provided at that point, - * make it the final one one. - */ - if (read_sched_clock == jiffy_sched_clock_read) - setup_sched_clock(jiffy_sched_clock_read, 32, HZ); - - sched_clock_poll(sched_clock_timer.data); -} - -static int sched_clock_suspend(void) -{ - sched_clock_poll(sched_clock_timer.data); - cd.suspended = true; - return 0; -} - -static void sched_clock_resume(void) -{ - cd.epoch_cyc = read_sched_clock(); - cd.epoch_cyc_copy = cd.epoch_cyc; - cd.suspended = false; -} - -static struct syscore_ops sched_clock_ops = { - .suspend = sched_clock_suspend, - .resume = sched_clock_resume, -}; - -static int __init sched_clock_syscore_init(void) -{ - register_syscore_ops(&sched_clock_ops); - return 0; -} -device_initcall(sched_clock_syscore_init); diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index abff4e9aaee0..98aee3258398 100644 --- a/arch/arm/kernel/time.c +++ b/arch/arm/kernel/time.c @@ -24,9 +24,9 @@ #include #include #include +#include #include -#include #include #include #include @@ -120,6 +120,4 @@ void __init time_init(void) machine_desc->init_time(); else clocksource_of_init(); - - sched_clock_postinit(); } diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c index bad361ec1666..7a55b5c95971 100644 --- a/arch/arm/mach-davinci/time.c +++ b/arch/arm/mach-davinci/time.c @@ -18,8 +18,8 @@ #include #include #include +#include -#include #include #include diff --git a/arch/arm/mach-imx/time.c b/arch/arm/mach-imx/time.c index fea91313678b..cd46529e9eaa 100644 --- a/arch/arm/mach-imx/time.c +++ b/arch/arm/mach-imx/time.c @@ -26,8 +26,8 @@ #include #include #include +#include -#include #include #include "common.h" diff --git a/arch/arm/mach-integrator/integrator_ap.c b/arch/arm/mach-integrator/integrator_ap.c index b23c8e4f28e8..aa4346227c41 100644 --- a/arch/arm/mach-integrator/integrator_ap.c +++ b/arch/arm/mach-integrator/integrator_ap.c @@ -41,6 +41,7 @@ #include #include #include +#include #include