#include <linux/cpu.h>
#include <linux/random.h>
#include <linux/delay.h>
-#include <linux/byteorder/swabb.h>
#include <linux/cpumask.h>
#include <linux/rcupreempt_trace.h>
-
-/*
- * Macro that prevents the compiler from reordering accesses, but does
- * absolutely -nothing- to prevent CPUs from reordering. This is used
- * only to mediate communication between mainline code and hardware
- * interrupt and NMI handlers.
- */
-#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
+#include <asm/byteorder.h>
/*
* PREEMPT_RCU data structures.
wait_queue_head_t sched_wq; /* Place for rcu_sched to sleep. */
};
+struct rcu_dyntick_sched {
+ int dynticks;
+ int dynticks_snap;
+ int sched_qs;
+ int sched_qs_snap;
+ int sched_dynticks_snap;
+};
+
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct rcu_dyntick_sched, rcu_dyntick_sched) = {
+ .dynticks = 1,
+};
+
+void rcu_qsctr_inc(int cpu)
+{
+ struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
+
+ rdssp->sched_qs++;
+}
+
+#ifdef CONFIG_NO_HZ
+
+void rcu_enter_nohz(void)
+{
+ static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
+
+ smp_mb(); /* CPUs seeing ++ must see prior RCU read-side crit sects */
+ __get_cpu_var(rcu_dyntick_sched).dynticks++;
+ WARN_ON_RATELIMIT(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1, &rs);
+}
+
+void rcu_exit_nohz(void)
+{
+ static DEFINE_RATELIMIT_STATE(rs, 10 * HZ, 1);
+
+ __get_cpu_var(rcu_dyntick_sched).dynticks++;
+ smp_mb(); /* CPUs seeing ++ must see later RCU read-side crit sects */
+ WARN_ON_RATELIMIT(!(__get_cpu_var(rcu_dyntick_sched).dynticks & 0x1),
+ &rs);
+}
+
+#endif /* CONFIG_NO_HZ */
+
+
static DEFINE_PER_CPU(struct rcu_data, rcu_data);
+
static struct rcu_ctrlblk rcu_ctrlblk = {
.fliplock = __SPIN_LOCK_UNLOCKED(rcu_ctrlblk.fliplock),
.completed = 0,
{ "idle", "waitack", "waitzero", "waitmb" };
#endif /* #ifdef CONFIG_RCU_TRACE */
-static cpumask_t rcu_cpu_online_map __read_mostly = CPU_MASK_NONE;
+static DECLARE_BITMAP(rcu_cpu_online_map, NR_CPUS) __read_mostly
+ = CPU_BITS_NONE;
/*
* Enum and per-CPU flag to determine when each CPU has seen
}
}
-DEFINE_PER_CPU_SHARED_ALIGNED(struct rcu_dyntick_sched, rcu_dyntick_sched) = {
- .dynticks = 1,
-};
-
#ifdef CONFIG_NO_HZ
static DEFINE_PER_CPU(int, rcu_update_flag);
}
}
+void rcu_nmi_enter(void)
+{
+ rcu_irq_enter();
+}
+
+void rcu_nmi_exit(void)
+{
+ rcu_irq_exit();
+}
+
static void dyntick_save_progress_counter(int cpu)
{
struct rcu_dyntick_sched *rdssp = &per_cpu(rcu_dyntick_sched, cpu);
/* Now ask each CPU for acknowledgement of the flip. */
- for_each_cpu_mask(cpu, rcu_cpu_online_map) {
+ for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map)) {
per_cpu(rcu_flip_flag, cpu) = rcu_flipped;
dyntick_save_progress_counter(cpu);
}
int cpu;
RCU_TRACE_ME(rcupreempt_trace_try_flip_a1);
- for_each_cpu_mask(cpu, rcu_cpu_online_map)
+ for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
if (rcu_try_flip_waitack_needed(cpu) &&
per_cpu(rcu_flip_flag, cpu) != rcu_flip_seen) {
RCU_TRACE_ME(rcupreempt_trace_try_flip_ae1);
/* Check to see if the sum of the "last" counters is zero. */
RCU_TRACE_ME(rcupreempt_trace_try_flip_z1);
- for_each_cpu_mask(cpu, rcu_cpu_online_map)
+ for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
sum += RCU_DATA_CPU(cpu)->rcu_flipctr[lastidx];
if (sum != 0) {
RCU_TRACE_ME(rcupreempt_trace_try_flip_ze1);
smp_mb(); /* ^^^^^^^^^^^^ */
/* Call for a memory barrier from each CPU. */
- for_each_cpu_mask(cpu, rcu_cpu_online_map) {
+ for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map)) {
per_cpu(rcu_mb_flag, cpu) = rcu_mb_needed;
dyntick_save_progress_counter(cpu);
}
int cpu;
RCU_TRACE_ME(rcupreempt_trace_try_flip_m1);
- for_each_cpu_mask(cpu, rcu_cpu_online_map)
+ for_each_cpu(cpu, to_cpumask(rcu_cpu_online_map))
if (rcu_try_flip_waitmb_needed(cpu) &&
per_cpu(rcu_mb_flag, cpu) != rcu_mb_done) {
RCU_TRACE_ME(rcupreempt_trace_try_flip_me1);
RCU_DATA_CPU(cpu)->rcu_flipctr[0] = 0;
RCU_DATA_CPU(cpu)->rcu_flipctr[1] = 0;
- cpu_clear(cpu, rcu_cpu_online_map);
+ cpumask_clear_cpu(cpu, to_cpumask(rcu_cpu_online_map));
spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
struct rcu_data *rdp;
spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags);
- cpu_set(cpu, rcu_cpu_online_map);
+ cpumask_set_cpu(cpu, to_cpumask(rcu_cpu_online_map));
spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
/*
* in -rt this does -not- necessarily result in all currently executing
* interrupt -handlers- having completed.
*/
-synchronize_rcu_xxx(__synchronize_sched, call_rcu_sched)
+void __synchronize_sched(void)
+{
+ struct rcu_synchronize rcu;
+
+ if (num_online_cpus() == 1)
+ return; /* blocking is gp if only one CPU! */
+
+ init_completion(&rcu.completion);
+ /* Will wake me after RCU finished. */
+ call_rcu_sched(&rcu.head, wakeme_after_rcu);
+ /* Wait for it. */
+ wait_for_completion(&rcu.completion);
+}
EXPORT_SYMBOL_GPL(__synchronize_sched);
/*
rcu_ctrlblk.sched_sleep = rcu_sched_sleeping;
spin_unlock_irqrestore(&rcu_ctrlblk.schedlock, flags);
- ret = 0;
+ ret = 0; /* unused */
__wait_event_interruptible(rcu_ctrlblk.sched_wq,
rcu_ctrlblk.sched_sleep != rcu_sched_sleeping,
ret);
- /*
- * Signals would prevent us from sleeping, and we cannot
- * do much with them in any case. So flush them.
- */
- if (ret)
- flush_signals(current);
couldsleepnext = 0;
} while (!kthread_should_stop());
* We don't need protection against CPU-Hotplug here
* since
* a) If a CPU comes online while we are iterating over the
- * cpu_online_map below, we would only end up making a
+ * cpu_online_mask below, we would only end up making a
* duplicate call to rcu_online_cpu() which sets the corresponding
* CPU's mask in the rcu_cpu_online_map.
*
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff