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Diffstat (limited to 'kernel/time/timer.c')
-rw-r--r--kernel/time/timer.c149
1 files changed, 67 insertions, 82 deletions
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 2d3f5c504939..2ece3aa5069c 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -90,8 +90,18 @@ struct tvec_base {
struct tvec tv5;
} ____cacheline_aligned;
+/*
+ * __TIMER_INITIALIZER() needs to set ->base to a valid pointer (because we've
+ * made NULL special, hint: lock_timer_base()) and we cannot get a compile time
+ * pointer to per-cpu entries because we don't know where we'll map the section,
+ * even for the boot cpu.
+ *
+ * And so we use boot_tvec_bases for boot CPU and per-cpu __tvec_bases for the
+ * rest of them.
+ */
struct tvec_base boot_tvec_bases;
EXPORT_SYMBOL(boot_tvec_bases);
+
static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases;
/* Functions below help us manage 'deferrable' flag */
@@ -1027,6 +1037,8 @@ int try_to_del_timer_sync(struct timer_list *timer)
EXPORT_SYMBOL(try_to_del_timer_sync);
#ifdef CONFIG_SMP
+static DEFINE_PER_CPU(struct tvec_base, __tvec_bases);
+
/**
* del_timer_sync - deactivate a timer and wait for the handler to finish.
* @timer: the timer to be deactivated
@@ -1532,64 +1544,6 @@ signed long __sched schedule_timeout_uninterruptible(signed long timeout)
}
EXPORT_SYMBOL(schedule_timeout_uninterruptible);
-static int init_timers_cpu(int cpu)
-{
- int j;
- struct tvec_base *base;
- static char tvec_base_done[NR_CPUS];
-
- if (!tvec_base_done[cpu]) {
- static char boot_done;
-
- if (boot_done) {
- /*
- * The APs use this path later in boot
- */
- base = kzalloc_node(sizeof(*base), GFP_KERNEL,
- cpu_to_node(cpu));
- if (!base)
- return -ENOMEM;
-
- /* Make sure tvec_base has TIMER_FLAG_MASK bits free */
- if (WARN_ON(base != tbase_get_base(base))) {
- kfree(base);
- return -ENOMEM;
- }
- per_cpu(tvec_bases, cpu) = base;
- } else {
- /*
- * This is for the boot CPU - we use compile-time
- * static initialisation because per-cpu memory isn't
- * ready yet and because the memory allocators are not
- * initialised either.
- */
- boot_done = 1;
- base = &boot_tvec_bases;
- }
- spin_lock_init(&base->lock);
- tvec_base_done[cpu] = 1;
- base->cpu = cpu;
- } else {
- base = per_cpu(tvec_bases, cpu);
- }
-
-
- for (j = 0; j < TVN_SIZE; j++) {
- INIT_LIST_HEAD(base->tv5.vec + j);
- INIT_LIST_HEAD(base->tv4.vec + j);
- INIT_LIST_HEAD(base->tv3.vec + j);
- INIT_LIST_HEAD(base->tv2.vec + j);
- }
- for (j = 0; j < TVR_SIZE; j++)
- INIT_LIST_HEAD(base->tv1.vec + j);
-
- base->timer_jiffies = jiffies;
- base->next_timer = base->timer_jiffies;
- base->active_timers = 0;
- base->all_timers = 0;
- return 0;
-}
-
#ifdef CONFIG_HOTPLUG_CPU
static void migrate_timer_list(struct tvec_base *new_base, struct list_head *head)
{
@@ -1631,55 +1585,86 @@ static void migrate_timers(int cpu)
migrate_timer_list(new_base, old_base->tv5.vec + i);
}
+ old_base->active_timers = 0;
+ old_base->all_timers = 0;
+
spin_unlock(&old_base->lock);
spin_unlock_irq(&new_base->lock);
put_cpu_var(tvec_bases);
}
-#endif /* CONFIG_HOTPLUG_CPU */
static int timer_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
- long cpu = (long)hcpu;
- int err;
-
- switch(action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- err = init_timers_cpu(cpu);
- if (err < 0)
- return notifier_from_errno(err);
- break;
-#ifdef CONFIG_HOTPLUG_CPU
+ switch (action) {
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- migrate_timers(cpu);
+ migrate_timers((long)hcpu);
break;
-#endif
default:
break;
}
+
return NOTIFY_OK;
}
-static struct notifier_block timers_nb = {
- .notifier_call = timer_cpu_notify,
-};
+static inline void timer_register_cpu_notifier(void)
+{
+ cpu_notifier(timer_cpu_notify, 0);
+}
+#else
+static inline void timer_register_cpu_notifier(void) { }
+#endif /* CONFIG_HOTPLUG_CPU */
+static void __init init_timer_cpu(struct tvec_base *base, int cpu)
+{
+ int j;
-void __init init_timers(void)
+ BUG_ON(base != tbase_get_base(base));
+
+ base->cpu = cpu;
+ per_cpu(tvec_bases, cpu) = base;
+ spin_lock_init(&base->lock);
+
+ for (j = 0; j < TVN_SIZE; j++) {
+ INIT_LIST_HEAD(base->tv5.vec + j);
+ INIT_LIST_HEAD(base->tv4.vec + j);
+ INIT_LIST_HEAD(base->tv3.vec + j);
+ INIT_LIST_HEAD(base->tv2.vec + j);
+ }
+ for (j = 0; j < TVR_SIZE; j++)
+ INIT_LIST_HEAD(base->tv1.vec + j);
+
+ base->timer_jiffies = jiffies;
+ base->next_timer = base->timer_jiffies;
+}
+
+static void __init init_timer_cpus(void)
{
- int err;
+ struct tvec_base *base;
+ int local_cpu = smp_processor_id();
+ int cpu;
+ for_each_possible_cpu(cpu) {
+ if (cpu == local_cpu)
+ base = &boot_tvec_bases;
+#ifdef CONFIG_SMP
+ else
+ base = per_cpu_ptr(&__tvec_bases, cpu);
+#endif
+
+ init_timer_cpu(base, cpu);
+ }
+}
+
+void __init init_timers(void)
+{
/* ensure there are enough low bits for flags in timer->base pointer */
BUILD_BUG_ON(__alignof__(struct tvec_base) & TIMER_FLAG_MASK);
- err = timer_cpu_notify(&timers_nb, (unsigned long)CPU_UP_PREPARE,
- (void *)(long)smp_processor_id());
- BUG_ON(err != NOTIFY_OK);
-
+ init_timer_cpus();
init_timer_stats();
- register_cpu_notifier(&timers_nb);
+ timer_register_cpu_notifier();
open_softirq(TIMER_SOFTIRQ, run_timer_softirq);
}