Dear RT Folks, I'm pleased to announce the 3.0.89-rt118 stable release.
You can get this release via the git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git branch: v3.0-rt Head SHA1: 5df5fdd22f799e1919b2def24b24b9f48abdba2f Or to build 3.0.89-rt118 directly, the following patches should be applied: http://www.kernel.org/pub/linux/kernel/v3.0/linux-3.0.tar.xz http://www.kernel.org/pub/linux/kernel/v3.0/patch-3.0.89.xz http://www.kernel.org/pub/linux/kernel/projects/rt/3.0/patch-3.0.89-rt118.patch.xz You can also build from 3.0.89-rt117 by applying the incremental patch: http://www.kernel.org/pub/linux/kernel/projects/rt/3.0/incr/patch-3.0.89-rt117-rt118.patch.xz Enjoy, -- Steve Changes from v3.0.89-rt117: --- Ivo Sieben (1): genirq: Set irq thread to RT priority on creation Mike Galbraith (1): x86/mce: fix mce timer interval Paul Gortmaker (1): list_bl.h: make list head locking RT safe Sebastian Andrzej Siewior (4): kernel/cpu: fix cpu down problem if kthread's cpu is going down kernel/hotplug: restore original cpu mask oncpu/down drm/i915: drop trace_i915_gem_ring_dispatch on rt genirq: do not invoke the affinity callback via a workqueue Steven Rostedt (5): sched/workqueue: Only wake up idle workers if not blocked on sleeping spin lock rt,ntp: Move call to schedule_delayed_work() to helper thread hwlat-detector: Update hwlat_detector to add outer loop detection hwlat-detector: Use trace_clock_local if available hwlat-detector: Use thread instead of stop machine Steven Rostedt (Red Hat) (2): hwlat-detect/trace: Export trace_clock_local for hwlat-detector Linux 3.0.89-rt118 Uwe Kleine-König (1): list_bl.h: fix it for for !SMP && !DEBUG_SPINLOCK Zhao Hongjiang (1): timers: prepare for full preemption improve ---- arch/x86/kernel/cpu/mcheck/mce.c | 4 +- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 2 + drivers/misc/hwlat_detector.c | 117 +++++++++++++++++----------- include/linux/interrupt.h | 1 + include/linux/list_bl.h | 28 ++++++- kernel/cpu.c | 29 ++++++- kernel/irq/manage.c | 89 +++++++++++++++++++-- kernel/sched.c | 4 +- kernel/time/ntp.c | 42 ++++++++++ kernel/timer.c | 8 +- kernel/trace/trace_clock.c | 1 + localversion-rt | 2 +- 12 files changed, 264 insertions(+), 63 deletions(-) --------------------------- diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c index c859bb4..e51191f 100644 --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1171,7 +1171,7 @@ static enum hrtimer_restart mce_start_timer(struct hrtimer *timer) *n = min(*n*2, round_jiffies_relative(check_interval*HZ)); hrtimer_forward(timer, timer->base->get_time(), - ns_to_ktime(jiffies_to_usecs(*n) * 1000)); + ns_to_ktime(jiffies_to_usecs(*n) * 1000ULL)); return HRTIMER_RESTART; } @@ -1452,7 +1452,7 @@ static void __mcheck_cpu_init_timer(void) if (!*n) return; - hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(*n) * 1000), + hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(*n) * 1000ULL), 0 , HRTIMER_MODE_REL_PINNED); } diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 1ca53ff..4d04a9f 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -1189,7 +1189,9 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data, } } +#ifndef CONFIG_PREEMPT_RT_BASE trace_i915_gem_ring_dispatch(ring, seqno); +#endif exec_start = batch_obj->gtt_offset + args->batch_start_offset; exec_len = args->batch_len; diff --git a/drivers/misc/hwlat_detector.c b/drivers/misc/hwlat_detector.c index b7b7c90..6f61d5f 100644 --- a/drivers/misc/hwlat_detector.c +++ b/drivers/misc/hwlat_detector.c @@ -41,7 +41,6 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/ring_buffer.h> -#include <linux/stop_machine.h> #include <linux/time.h> #include <linux/hrtimer.h> #include <linux/kthread.h> @@ -51,6 +50,7 @@ #include <linux/version.h> #include <linux/delay.h> #include <linux/slab.h> +#include <linux/trace_clock.h> #define BUF_SIZE_DEFAULT 262144UL /* 8K*(sizeof(entry)) */ #define BUF_FLAGS (RB_FL_OVERWRITE) /* no block on full */ @@ -106,7 +106,6 @@ struct data; /* Global state */ /* Sampling functions */ static int __buffer_add_sample(struct sample *sample); static struct sample *buffer_get_sample(struct sample *sample); -static int get_sample(void *unused); /* Threading and state */ static int kthread_fn(void *unused); @@ -143,11 +142,12 @@ static void detector_exit(void); struct sample { u64 seqnum; /* unique sequence */ u64 duration; /* ktime delta */ + u64 outer_duration; /* ktime delta (outer loop) */ struct timespec timestamp; /* wall time */ unsigned long lost; }; -/* keep the global state somewhere. Mostly used under stop_machine. */ +/* keep the global state somewhere. */ static struct data { struct mutex lock; /* protect changes */ @@ -170,7 +170,7 @@ static struct data { * @sample: The new latency sample value * * This receives a new latency sample and records it in a global ring buffer. - * No additional locking is used in this case - suited for stop_machine use. + * No additional locking is used in this case. */ static int __buffer_add_sample(struct sample *sample) { @@ -210,29 +210,60 @@ static struct sample *buffer_get_sample(struct sample *sample) return sample; } +#ifndef CONFIG_TRACING +#define time_type ktime_t +#define time_get() ktime_get() +#define time_to_us(x) ktime_to_us(x) +#define time_sub(a, b) ktime_sub(a, b) +#define init_time(a, b) (a).tv64 = b +#define time_u64(a) (a).tv64 +#else +#define time_type u64 +#define time_get() trace_clock_local() +#define time_to_us(x) div_u64(x, 1000) +#define time_sub(a, b) ((a) - (b)) +#define init_time(a, b) a = b +#define time_u64(a) a +#endif /** * get_sample - sample the CPU TSC and look for likely hardware latencies - * @unused: This is not used but is a part of the stop_machine API * * Used to repeatedly capture the CPU TSC (or similar), looking for potential - * hardware-induced latency. Called under stop_machine, with data.lock held. + * hardware-induced latency. Called with interrupts disabled and with data.lock held. */ -static int get_sample(void *unused) +static int get_sample(void) { - ktime_t start, t1, t2; + time_type start, t1, t2, last_t2; s64 diff, total = 0; u64 sample = 0; - int ret = 1; + u64 outer_sample = 0; + int ret = -1; - start = ktime_get(); /* start timestamp */ + init_time(last_t2, 0); + start = time_get(); /* start timestamp */ do { - t1 = ktime_get(); /* we'll look for a discontinuity */ - t2 = ktime_get(); + t1 = time_get(); /* we'll look for a discontinuity */ + t2 = time_get(); + + if (time_u64(last_t2)) { + /* Check the delta from the outer loop (t2 to next t1) */ + diff = time_to_us(time_sub(t1, last_t2)); + /* This shouldn't happen */ + if (diff < 0) { + printk(KERN_ERR BANNER "time running backwards\n"); + goto out; + } + if (diff > outer_sample) + outer_sample = diff; + } + last_t2 = t2; + + total = time_to_us(time_sub(t2, start)); /* sample width */ - total = ktime_to_us(ktime_sub(t2, start)); /* sample width */ - diff = ktime_to_us(ktime_sub(t2, t1)); /* current diff */ + /* This checks the inner loop (t1 to t2) */ + diff = time_to_us(time_sub(t2, t1)); /* current diff */ /* This shouldn't happen */ if (diff < 0) { @@ -245,13 +276,18 @@ static int get_sample(void *unused) } while (total <= data.sample_width); + ret = 0; + /* If we exceed the threshold value, we have found a hardware latency */ - if (sample > data.threshold) { + if (sample > data.threshold || outer_sample > data.threshold) { struct sample s; + ret = 1; + data.count++; s.seqnum = data.count; s.duration = sample; + s.outer_duration = outer_sample; s.timestamp = CURRENT_TIME; __buffer_add_sample(&s); @@ -260,7 +296,6 @@ static int get_sample(void *unused) data.max_sample = sample; } - ret = 0; out: return ret; } @@ -270,32 +305,30 @@ out: * @unused: A required part of the kthread API. * * Used to periodically sample the CPU TSC via a call to get_sample. We - * use stop_machine, whith does (intentionally) introduce latency since we + * disable interrupts, which does (intentionally) introduce latency since we * need to ensure nothing else might be running (and thus pre-empting). * Obviously this should never be used in production environments. * - * stop_machine will schedule us typically only on CPU0 which is fine for - * almost every real-world hardware latency situation - but we might later - * generalize this if we find there are any actualy systems with alternate - * SMI delivery or other non CPU0 hardware latencies. + * Currently this runs on which ever CPU it was scheduled on, but most + * real-worald hardware latency situations occur across several CPUs, + * but we might later generalize this if we find there are any actualy + * systems with alternate SMI delivery or other hardware latencies. */ static int kthread_fn(void *unused) { - int err = 0; - u64 interval = 0; + int ret; + u64 interval; while (!kthread_should_stop()) { mutex_lock(&data.lock); - err = stop_machine(get_sample, unused, 0); - if (err) { - /* Houston, we have a problem */ - mutex_unlock(&data.lock); - goto err_out; - } + local_irq_disable(); + ret = get_sample(); + local_irq_enable(); - wake_up(&data.wq); /* wake up reader(s) */ + if (ret > 0) + wake_up(&data.wq); /* wake up reader(s) */ interval = data.sample_window - data.sample_width; do_div(interval, USEC_PER_MSEC); /* modifies interval value */ @@ -303,15 +336,10 @@ static int kthread_fn(void *unused) mutex_unlock(&data.lock); if (msleep_interruptible(interval)) - goto out; + break; } - goto out; -err_out: - printk(KERN_ERR BANNER "could not call stop_machine, disabling\n"); - enabled = 0; -out: - return err; + return 0; } /** @@ -407,8 +435,7 @@ out: * This function provides a generic read implementation for the global state * "data" structure debugfs filesystem entries. It would be nice to use * simple_attr_read directly, but we need to make sure that the data.lock - * spinlock is held during the actual read (even though we likely won't ever - * actually race here as the updater runs under a stop_machine context). + * is held during the actual read. */ static ssize_t simple_data_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos, const u64 *entry) @@ -443,8 +470,7 @@ static ssize_t simple_data_read(struct file *filp, char __user *ubuf, * This function provides a generic write implementation for the global state * "data" structure debugfs filesystem entries. It would be nice to use * simple_attr_write directly, but we need to make sure that the data.lock - * spinlock is held during the actual write (even though we likely won't ever - * actually race here as the updater runs under a stop_machine context). + * is held during the actual write. */ static ssize_t simple_data_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos, u64 *entry) @@ -738,10 +764,11 @@ static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf, } } - len = snprintf(buf, sizeof(buf), "%010lu.%010lu\t%llu\n", - sample->timestamp.tv_sec, - sample->timestamp.tv_nsec, - sample->duration); + len = snprintf(buf, sizeof(buf), "%010lu.%010lu\t%llu\t%llu\n", + sample->timestamp.tv_sec, + sample->timestamp.tv_nsec, + sample->duration, + sample->outer_duration); /* handling partial reads is more trouble than it's worth */ diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 71c2c0b..9f67f91 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -255,6 +255,7 @@ struct irq_affinity_notify { unsigned int irq; struct kref kref; struct work_struct work; + struct list_head list; void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); void (*release)(struct kref *ref); }; diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h index 31f9d75..becd7a6 100644 --- a/include/linux/list_bl.h +++ b/include/linux/list_bl.h @@ -2,6 +2,7 @@ #define _LINUX_LIST_BL_H #include <linux/list.h> +#include <linux/spinlock.h> #include <linux/bit_spinlock.h> /* @@ -32,13 +33,22 @@ struct hlist_bl_head { struct hlist_bl_node *first; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spinlock_t lock; +#endif }; struct hlist_bl_node { struct hlist_bl_node *next, **pprev; }; -#define INIT_HLIST_BL_HEAD(ptr) \ - ((ptr)->first = NULL) + +static inline void INIT_HLIST_BL_HEAD(struct hlist_bl_head *h) +{ + h->first = NULL; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spin_lock_init(&h->lock); +#endif +} static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h) { @@ -117,12 +127,26 @@ static inline void hlist_bl_del_init(struct hlist_bl_node *n) static inline void hlist_bl_lock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(0, (unsigned long *)b); +#else + raw_spin_lock(&b->lock); +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __set_bit(0, (unsigned long *)b); +#endif +#endif } static inline void hlist_bl_unlock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE __bit_spin_unlock(0, (unsigned long *)b); +#else +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __clear_bit(0, (unsigned long *)b); +#endif + raw_spin_unlock(&b->lock); +#endif } /** diff --git a/kernel/cpu.c b/kernel/cpu.c index 3bcbf99..4abfd5d 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -78,6 +78,7 @@ struct hotplug_pcp { int refcount; int grab_lock; struct completion synced; + struct completion unplug_wait; #ifdef CONFIG_PREEMPT_RT_FULL spinlock_t lock; #else @@ -175,6 +176,7 @@ static int sync_unplug_thread(void *data) { struct hotplug_pcp *hp = data; + wait_for_completion(&hp->unplug_wait); preempt_disable(); hp->unplug = current; wait_for_pinned_cpus(hp); @@ -240,6 +242,14 @@ static void __cpu_unplug_sync(struct hotplug_pcp *hp) wait_for_completion(&hp->synced); } +static void __cpu_unplug_wait(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + complete(&hp->unplug_wait); + wait_for_completion(&hp->synced); +} + /* * Start the sync_unplug_thread on the target cpu and wait for it to * complete. @@ -263,6 +273,7 @@ static int cpu_unplug_begin(unsigned int cpu) tell_sched_cpu_down_begin(cpu); init_completion(&hp->synced); + init_completion(&hp->unplug_wait); hp->sync_tsk = kthread_create(sync_unplug_thread, hp, "sync_unplug/%d", cpu); if (IS_ERR(hp->sync_tsk)) { @@ -278,8 +289,7 @@ static int cpu_unplug_begin(unsigned int cpu) * wait for tasks that are going to enter these sections and * we must not have them block. */ - __cpu_unplug_sync(hp); - + wake_up_process(hp->sync_tsk); return 0; } @@ -487,6 +497,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) .hcpu = hcpu, }; cpumask_var_t cpumask; + cpumask_var_t cpumask_org; if (num_online_cpus() == 1) return -EBUSY; @@ -497,6 +508,12 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) /* Move the downtaker off the unplug cpu */ if (!alloc_cpumask_var(&cpumask, GFP_KERNEL)) return -ENOMEM; + if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL)) { + free_cpumask_var(cpumask); + return -ENOMEM; + } + + cpumask_copy(cpumask_org, tsk_cpus_allowed(current)); cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu)); set_cpus_allowed_ptr(current, cpumask); free_cpumask_var(cpumask); @@ -505,7 +522,8 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) if (mycpu == cpu) { printk(KERN_ERR "Yuck! Still on unplug CPU\n!"); migrate_enable(); - return -EBUSY; + err = -EBUSY; + goto restore_cpus; } cpu_hotplug_begin(); @@ -524,6 +542,8 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) goto out_release; } + __cpu_unplug_wait(cpu); + /* Notifiers are done. Don't let any more tasks pin this CPU. */ cpu_unplug_sync(cpu); @@ -561,6 +581,9 @@ out_cancel: cpu_hotplug_done(); if (!err) cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu); +restore_cpus: + set_cpus_allowed_ptr(current, cpumask_org); + free_cpumask_var(cpumask_org); return err; } diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index d750268..3d7d5f6 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -141,6 +141,62 @@ static inline void irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { } #endif +#ifdef CONFIG_PREEMPT_RT_FULL +static void _irq_affinity_notify(struct irq_affinity_notify *notify); +static struct task_struct *set_affinity_helper; +static LIST_HEAD(affinity_list); +static DEFINE_RAW_SPINLOCK(affinity_list_lock); + +static int set_affinity_thread(void *unused) +{ + while (1) { + struct irq_affinity_notify *notify; + int empty; + + set_current_state(TASK_INTERRUPTIBLE); + + raw_spin_lock_irq(&affinity_list_lock); + empty = list_empty(&affinity_list); + raw_spin_unlock_irq(&affinity_list_lock); + + if (empty) + schedule(); + if (kthread_should_stop()) + break; + set_current_state(TASK_RUNNING); +try_next: + notify = NULL; + + raw_spin_lock_irq(&affinity_list_lock); + if (!list_empty(&affinity_list)) { + notify = list_first_entry(&affinity_list, + struct irq_affinity_notify, list); + list_del_init(¬ify->list); + } + raw_spin_unlock_irq(&affinity_list_lock); + + if (!notify) + continue; + _irq_affinity_notify(notify); + goto try_next; + } + return 0; +} + +static void init_helper_thread(void) +{ + if (set_affinity_helper) + return; + set_affinity_helper = kthread_run(set_affinity_thread, NULL, + "affinity-cb"); + WARN_ON(IS_ERR(set_affinity_helper)); +} +#else + +static inline void init_helper_thread(void) { } + +#endif + int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) { struct irq_chip *chip = irq_data_get_irq_chip(data); @@ -166,7 +222,17 @@ int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask) if (desc->affinity_notify) { kref_get(&desc->affinity_notify->kref); + +#ifdef CONFIG_PREEMPT_RT_FULL + raw_spin_lock(&affinity_list_lock); + if (list_empty(&desc->affinity_notify->list)) + list_add_tail(&affinity_list, + &desc->affinity_notify->list); + raw_spin_unlock(&affinity_list_lock); + wake_up_process(set_affinity_helper); +#else schedule_work(&desc->affinity_notify->work); +#endif } irqd_set(data, IRQD_AFFINITY_SET); @@ -207,10 +273,8 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) } EXPORT_SYMBOL_GPL(irq_set_affinity_hint); -static void irq_affinity_notify(struct work_struct *work) +static void _irq_affinity_notify(struct irq_affinity_notify *notify) { - struct irq_affinity_notify *notify = - container_of(work, struct irq_affinity_notify, work); struct irq_desc *desc = irq_to_desc(notify->irq); cpumask_var_t cpumask; unsigned long flags; @@ -232,6 +296,13 @@ out: kref_put(¬ify->kref, notify->release); } +static void irq_affinity_notify(struct work_struct *work) +{ + struct irq_affinity_notify *notify = + container_of(work, struct irq_affinity_notify, work); + _irq_affinity_notify(notify); +} + /** * irq_set_affinity_notifier - control notification of IRQ affinity changes * @irq: Interrupt for which to enable/disable notification @@ -261,6 +332,8 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) notify->irq = irq; kref_init(¬ify->kref); INIT_WORK(¬ify->work, irq_affinity_notify); + INIT_LIST_HEAD(¬ify->list); + init_helper_thread(); } raw_spin_lock_irqsave(&desc->lock, flags); @@ -780,9 +853,6 @@ static irqreturn_t irq_thread_fn(struct irq_desc *desc, */ static int irq_thread(void *data) { - static const struct sched_param param = { - .sched_priority = MAX_USER_RT_PRIO/2, - }; struct irqaction *action = data; struct irq_desc *desc = irq_to_desc(action->irq); irqreturn_t (*handler_fn)(struct irq_desc *desc, @@ -795,7 +865,6 @@ static int irq_thread(void *data) else handler_fn = irq_thread_fn; - sched_setscheduler(current, SCHED_FIFO, ¶m); current->irqaction = action; while (!irq_wait_for_interrupt(action)) { @@ -932,11 +1001,17 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ if (new->thread_fn && !nested) { struct task_struct *t; + static const struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; t = kthread_create(irq_thread, new, "irq/%d-%s", irq, new->name); if (IS_ERR(t)) return PTR_ERR(t); + + sched_setscheduler(t, SCHED_FIFO, ¶m); + /* * We keep the reference to the task struct even if * the thread dies to avoid that the interrupt code diff --git a/kernel/sched.c b/kernel/sched.c index 96dd9c2..59bb8bc 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -4436,8 +4436,10 @@ static inline void sched_submit_work(struct task_struct *tsk) /* * If a worker went to sleep, notify and ask workqueue whether * it wants to wake up a task to maintain concurrency. + * Only call wake up if prev isn't blocked on a sleeping + * spin lock. */ - if (tsk->flags & PF_WQ_WORKER) + if (tsk->flags & PF_WQ_WORKER && !tsk->saved_state) wq_worker_sleeping(tsk); /* diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 8b3a185..fa0c206 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -10,6 +10,7 @@ #include <linux/workqueue.h> #include <linux/hrtimer.h> #include <linux/jiffies.h> +#include <linux/kthread.h> #include <linux/math64.h> #include <linux/timex.h> #include <linux/time.h> @@ -494,11 +495,52 @@ static void sync_cmos_clock(struct work_struct *work) schedule_delayed_work(&sync_cmos_work, timespec_to_jiffies(&next)); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * RT can not call schedule_delayed_work from real interrupt context. + * Need to make a thread to do the real work. + */ +static struct task_struct *cmos_delay_thread; +static bool do_cmos_delay; + +static int run_cmos_delay(void *ignore) +{ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (do_cmos_delay) { + do_cmos_delay = false; + schedule_delayed_work(&sync_cmos_work, 0); + } + schedule(); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +static void notify_cmos_timer(void) +{ + if (!no_sync_cmos_clock) { + do_cmos_delay = true; + /* Make visible before waking up process */ + smp_wmb(); + wake_up_process(cmos_delay_thread); + } +} + +static __init int create_cmos_delay_thread(void) +{ + cmos_delay_thread = kthread_run(run_cmos_delay, NULL, "kcmosdelayd"); + BUG_ON(!cmos_delay_thread); + return 0; +} +early_initcall(create_cmos_delay_thread); +#else static void notify_cmos_timer(void) { if (!no_sync_cmos_clock) schedule_delayed_work(&sync_cmos_work, 0); } +#endif /* CONFIG_PREEMPT_RT_FULL */ #else static inline void notify_cmos_timer(void) { } diff --git a/kernel/timer.c b/kernel/timer.c index 2e21a6c..07070cb 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -76,7 +76,9 @@ struct tvec_root { struct tvec_base { spinlock_t lock; struct timer_list *running_timer; +#ifdef CONFIG_PREEMPT_RT_FULL wait_queue_head_t wait_for_running_timer; +#endif unsigned long timer_jiffies; unsigned long next_timer; struct tvec_root tv1; @@ -930,7 +932,7 @@ static void wait_for_running_timer(struct timer_list *timer) base->running_timer != timer); } -# define wakeup_timer_waiters(b) wake_up(&(b)->wait_for_tunning_timer) +# define wakeup_timer_waiters(b) wake_up(&(b)->wait_for_running_timer) #else static inline void wait_for_running_timer(struct timer_list *timer) { @@ -1183,7 +1185,7 @@ static inline void __run_timers(struct tvec_base *base) spin_lock_irq(&base->lock); } } - wake_up(&base->wait_for_running_timer); + wakeup_timer_waiters(base); spin_unlock_irq(&base->lock); } @@ -1706,7 +1708,9 @@ static int __cpuinit init_timers_cpu(int cpu) base = &boot_tvec_bases; } spin_lock_init(&base->lock); +#ifdef CONFIG_PREEMPT_RT_FULL init_waitqueue_head(&base->wait_for_running_timer); +#endif tvec_base_done[cpu] = 1; } else { base = per_cpu(tvec_bases, cpu); diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c index 6302747..e5163ab 100644 --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -44,6 +44,7 @@ u64 notrace trace_clock_local(void) return clock; } +EXPORT_SYMBOL_GPL(trace_clock_local); /* * trace_clock(): 'between' trace clock. Not completely serialized, diff --git a/localversion-rt b/localversion-rt index 9788245..4e32122 100644 --- a/localversion-rt +++ b/localversion-rt @@ -1 +1 @@ --rt117 +-rt118 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
