*/
static DEFINE_PER_CPU(struct task_struct *, rcu_cpu_kthread_task);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_status);
-DEFINE_PER_CPU(int, rcu_cpu_kthread_cpu);
DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops);
DEFINE_PER_CPU(char, rcu_cpu_has_work);
#endif /* #ifdef CONFIG_RCU_BOOST */
-static void rcu_node_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu);
+static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu);
static void invoke_rcu_core(void);
static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp);
DEFINE_PER_CPU(struct rcu_dynticks, rcu_dynticks) = {
.dynticks_nesting = DYNTICK_TASK_EXIT_IDLE,
.dynticks = ATOMIC_INIT(1),
+#if defined(CONFIG_RCU_USER_QS) && !defined(CONFIG_RCU_USER_QS_FORCE)
+ .ignore_user_qs = true,
+#endif
};
static int blimit = 10; /* Maximum callbacks per rcu_do_batch. */
}
/*
- * If the specified CPU is offline, tell the caller that it is in
- * a quiescent state. Otherwise, whack it with a reschedule IPI.
- * Grace periods can end up waiting on an offline CPU when that
- * CPU is in the process of coming online -- it will be added to the
- * rcu_node bitmasks before it actually makes it online. The same thing
- * can happen while a CPU is in the process of coming online. Because this
- * race is quite rare, we check for it after detecting that the grace
- * period has been delayed rather than checking each and every CPU
- * each and every time we start a new grace period.
- */
-static int rcu_implicit_offline_qs(struct rcu_data *rdp)
-{
- /*
- * If the CPU is offline for more than a jiffy, it is in a quiescent
- * state. We can trust its state not to change because interrupts
- * are disabled. The reason for the jiffy's worth of slack is to
- * handle CPUs initializing on the way up and finding their way
- * to the idle loop on the way down.
- */
- if (cpu_is_offline(rdp->cpu) &&
- ULONG_CMP_LT(rdp->rsp->gp_start + 2, jiffies)) {
- trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, "ofl");
- rdp->offline_fqs++;
- return 1;
- }
- return 0;
-}
-
-/*
- * rcu_idle_enter_common - inform RCU that current CPU is moving towards idle
+ * rcu_eqs_enter_common - current CPU is moving towards extended quiescent state
*
* If the new value of the ->dynticks_nesting counter now is zero,
* we really have entered idle, and must do the appropriate accounting.
* The caller must have disabled interrupts.
*/
-static void rcu_idle_enter_common(struct rcu_dynticks *rdtp, long long oldval)
+static void rcu_eqs_enter_common(struct rcu_dynticks *rdtp, long long oldval,
+ bool user)
{
trace_rcu_dyntick("Start", oldval, 0);
- if (!is_idle_task(current)) {
+ if (!user && !is_idle_task(current)) {
struct task_struct *idle = idle_task(smp_processor_id());
trace_rcu_dyntick("Error on entry: not idle task", oldval, 0);
WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1);
/*
- * The idle task is not permitted to enter the idle loop while
+ * It is illegal to enter an extended quiescent state while
* in an RCU read-side critical section.
*/
rcu_lockdep_assert(!lock_is_held(&rcu_lock_map),
"Illegal idle entry in RCU-sched read-side critical section.");
}
+/*
+ * Enter an RCU extended quiescent state, which can be either the
+ * idle loop or adaptive-tickless usermode execution.
+ */
+static void rcu_eqs_enter(bool user)
+{
+ long long oldval;
+ struct rcu_dynticks *rdtp;
+
+ rdtp = &__get_cpu_var(rcu_dynticks);
+ oldval = rdtp->dynticks_nesting;
+ WARN_ON_ONCE((oldval & DYNTICK_TASK_NEST_MASK) == 0);
+ if ((oldval & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE)
+ rdtp->dynticks_nesting = 0;
+ else
+ rdtp->dynticks_nesting -= DYNTICK_TASK_NEST_VALUE;
+ rcu_eqs_enter_common(rdtp, oldval, user);
+}
+
/**
* rcu_idle_enter - inform RCU that current CPU is entering idle
*
void rcu_idle_enter(void)
{
unsigned long flags;
- long long oldval;
+
+ local_irq_save(flags);
+ rcu_eqs_enter(false);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(rcu_idle_enter);
+
+#ifdef CONFIG_RCU_USER_QS
+/**
+ * rcu_user_enter - inform RCU that we are resuming userspace.
+ *
+ * Enter RCU idle mode right before resuming userspace. No use of RCU
+ * is permitted between this call and rcu_user_exit(). This way the
+ * CPU doesn't need to maintain the tick for RCU maintenance purposes
+ * when the CPU runs in userspace.
+ */
+void rcu_user_enter(void)
+{
+ unsigned long flags;
struct rcu_dynticks *rdtp;
+ /*
+ * Some contexts may involve an exception occuring in an irq,
+ * leading to that nesting:
+ * rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
+ * This would mess up the dyntick_nesting count though. And rcu_irq_*()
+ * helpers are enough to protect RCU uses inside the exception. So
+ * just return immediately if we detect we are in an IRQ.
+ */
+ if (in_interrupt())
+ return;
+
+ WARN_ON_ONCE(!current->mm);
+
local_irq_save(flags);
rdtp = &__get_cpu_var(rcu_dynticks);
- oldval = rdtp->dynticks_nesting;
- WARN_ON_ONCE((oldval & DYNTICK_TASK_NEST_MASK) == 0);
- if ((oldval & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE)
- rdtp->dynticks_nesting = 0;
- else
- rdtp->dynticks_nesting -= DYNTICK_TASK_NEST_VALUE;
- rcu_idle_enter_common(rdtp, oldval);
+ if (!rdtp->ignore_user_qs && !rdtp->in_user) {
+ rdtp->in_user = true;
+ rcu_eqs_enter(true);
+ }
local_irq_restore(flags);
}
-EXPORT_SYMBOL_GPL(rcu_idle_enter);
+
+/**
+ * rcu_user_enter_after_irq - inform RCU that we are going to resume userspace
+ * after the current irq returns.
+ *
+ * This is similar to rcu_user_enter() but in the context of a non-nesting
+ * irq. After this call, RCU enters into idle mode when the interrupt
+ * returns.
+ */
+void rcu_user_enter_after_irq(void)
+{
+ unsigned long flags;
+ struct rcu_dynticks *rdtp;
+
+ local_irq_save(flags);
+ rdtp = &__get_cpu_var(rcu_dynticks);
+ /* Ensure this irq is interrupting a non-idle RCU state. */
+ WARN_ON_ONCE(!(rdtp->dynticks_nesting & DYNTICK_TASK_MASK));
+ rdtp->dynticks_nesting = 1;
+ local_irq_restore(flags);
+}
+#endif /* CONFIG_RCU_USER_QS */
/**
* rcu_irq_exit - inform RCU that current CPU is exiting irq towards idle
if (rdtp->dynticks_nesting)
trace_rcu_dyntick("--=", oldval, rdtp->dynticks_nesting);
else
- rcu_idle_enter_common(rdtp, oldval);
+ rcu_eqs_enter_common(rdtp, oldval, true);
local_irq_restore(flags);
}
/*
- * rcu_idle_exit_common - inform RCU that current CPU is moving away from idle
+ * rcu_eqs_exit_common - current CPU moving away from extended quiescent state
*
* If the new value of the ->dynticks_nesting counter was previously zero,
* we really have exited idle, and must do the appropriate accounting.
* The caller must have disabled interrupts.
*/
-static void rcu_idle_exit_common(struct rcu_dynticks *rdtp, long long oldval)
+static void rcu_eqs_exit_common(struct rcu_dynticks *rdtp, long long oldval,
+ int user)
{
smp_mb__before_atomic_inc(); /* Force ordering w/previous sojourn. */
atomic_inc(&rdtp->dynticks);
WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1));
rcu_cleanup_after_idle(smp_processor_id());
trace_rcu_dyntick("End", oldval, rdtp->dynticks_nesting);
- if (!is_idle_task(current)) {
+ if (!user && !is_idle_task(current)) {
struct task_struct *idle = idle_task(smp_processor_id());
trace_rcu_dyntick("Error on exit: not idle task",
}
}
+/*
+ * Exit an RCU extended quiescent state, which can be either the
+ * idle loop or adaptive-tickless usermode execution.
+ */
+static void rcu_eqs_exit(bool user)
+{
+ struct rcu_dynticks *rdtp;
+ long long oldval;
+
+ rdtp = &__get_cpu_var(rcu_dynticks);
+ oldval = rdtp->dynticks_nesting;
+ WARN_ON_ONCE(oldval < 0);
+ if (oldval & DYNTICK_TASK_NEST_MASK)
+ rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE;
+ else
+ rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
+ rcu_eqs_exit_common(rdtp, oldval, user);
+}
+
/**
* rcu_idle_exit - inform RCU that current CPU is leaving idle
*
* now starting.
*/
void rcu_idle_exit(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ rcu_eqs_exit(false);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(rcu_idle_exit);
+
+#ifdef CONFIG_RCU_USER_QS
+/**
+ * rcu_user_exit - inform RCU that we are exiting userspace.
+ *
+ * Exit RCU idle mode while entering the kernel because it can
+ * run a RCU read side critical section anytime.
+ */
+void rcu_user_exit(void)
{
unsigned long flags;
struct rcu_dynticks *rdtp;
- long long oldval;
+
+ /*
+ * Some contexts may involve an exception occuring in an irq,
+ * leading to that nesting:
+ * rcu_irq_enter() rcu_user_exit() rcu_user_exit() rcu_irq_exit()
+ * This would mess up the dyntick_nesting count though. And rcu_irq_*()
+ * helpers are enough to protect RCU uses inside the exception. So
+ * just return immediately if we detect we are in an IRQ.
+ */
+ if (in_interrupt())
+ return;
local_irq_save(flags);
rdtp = &__get_cpu_var(rcu_dynticks);
- oldval = rdtp->dynticks_nesting;
- WARN_ON_ONCE(oldval < 0);
- if (oldval & DYNTICK_TASK_NEST_MASK)
- rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE;
- else
- rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
- rcu_idle_exit_common(rdtp, oldval);
+ if (rdtp->in_user) {
+ rdtp->in_user = false;
+ rcu_eqs_exit(true);
+ }
local_irq_restore(flags);
}
-EXPORT_SYMBOL_GPL(rcu_idle_exit);
+
+/**
+ * rcu_user_exit_after_irq - inform RCU that we won't resume to userspace
+ * idle mode after the current non-nesting irq returns.
+ *
+ * This is similar to rcu_user_exit() but in the context of an irq.
+ * This is called when the irq has interrupted a userspace RCU idle mode
+ * context. When the current non-nesting interrupt returns after this call,
+ * the CPU won't restore the RCU idle mode.
+ */
+void rcu_user_exit_after_irq(void)
+{
+ unsigned long flags;
+ struct rcu_dynticks *rdtp;
+
+ local_irq_save(flags);
+ rdtp = &__get_cpu_var(rcu_dynticks);
+ /* Ensure we are interrupting an RCU idle mode. */
+ WARN_ON_ONCE(rdtp->dynticks_nesting & DYNTICK_TASK_NEST_MASK);
+ rdtp->dynticks_nesting += DYNTICK_TASK_EXIT_IDLE;
+ local_irq_restore(flags);
+}
+#endif /* CONFIG_RCU_USER_QS */
/**
* rcu_irq_enter - inform RCU that current CPU is entering irq away from idle
if (oldval)
trace_rcu_dyntick("++=", oldval, rdtp->dynticks_nesting);
else
- rcu_idle_exit_common(rdtp, oldval);
+ rcu_eqs_exit_common(rdtp, oldval, true);
local_irq_restore(flags);
}
}
EXPORT_SYMBOL(rcu_is_cpu_idle);
+#ifdef CONFIG_RCU_USER_QS
+void rcu_user_hooks_switch(struct task_struct *prev,
+ struct task_struct *next)
+{
+ struct rcu_dynticks *rdtp;
+
+ /* Interrupts are disabled in context switch */
+ rdtp = &__get_cpu_var(rcu_dynticks);
+ if (!rdtp->ignore_user_qs) {
+ clear_tsk_thread_flag(prev, TIF_NOHZ);
+ set_tsk_thread_flag(next, TIF_NOHZ);
+ }
+}
+#endif /* #ifdef CONFIG_RCU_USER_QS */
+
#if defined(CONFIG_PROVE_RCU) && defined(CONFIG_HOTPLUG_CPU)
/*
* Return true if the specified CPU has passed through a quiescent
* state by virtue of being in or having passed through an dynticks
* idle state since the last call to dyntick_save_progress_counter()
- * for this same CPU.
+ * for this same CPU, or by virtue of having been offline.
*/
static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
{
return 1;
}
- /* Go check for the CPU being offline. */
- return rcu_implicit_offline_qs(rdp);
+ /*
+ * Check for the CPU being offline, but only if the grace period
+ * is old enough. We don't need to worry about the CPU changing
+ * state: If we see it offline even once, it has been through a
+ * quiescent state.
+ *
+ * The reason for insisting that the grace period be at least
+ * one jiffy old is that CPUs that are not quite online and that
+ * have just gone offline can still execute RCU read-side critical
+ * sections.
+ */
+ if (ULONG_CMP_GE(rdp->rsp->gp_start + 2, jiffies))
+ return 0; /* Grace period is not old enough. */
+ barrier();
+ if (cpu_is_offline(rdp->cpu)) {
+ trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, "ofl");
+ rdp->offline_fqs++;
+ return 1;
+ }
+ return 0;
}
static int jiffies_till_stall_check(void)
rcu_for_each_leaf_node(rsp, rnp) {
raw_spin_lock_irqsave(&rnp->lock, flags);
ndetected += rcu_print_task_stall(rnp);
+ if (rnp->qsmask != 0) {
+ for (cpu = 0; cpu <= rnp->grphi - rnp->grplo; cpu++)
+ if (rnp->qsmask & (1UL << cpu)) {
+ print_cpu_stall_info(rsp,
+ rnp->grplo + cpu);
+ ndetected++;
+ }
+ }
raw_spin_unlock_irqrestore(&rnp->lock, flags);
- if (rnp->qsmask == 0)
- continue;
- for (cpu = 0; cpu <= rnp->grphi - rnp->grplo; cpu++)
- if (rnp->qsmask & (1UL << cpu)) {
- print_cpu_stall_info(rsp, rnp->grplo + cpu);
- ndetected++;
- }
}
/*
j = ACCESS_ONCE(jiffies);
js = ACCESS_ONCE(rsp->jiffies_stall);
rnp = rdp->mynode;
- if ((ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && ULONG_CMP_GE(j, js)) {
+ if (rcu_gp_in_progress(rsp) &&
+ (ACCESS_ONCE(rnp->qsmask) & rdp->grpmask) && ULONG_CMP_GE(j, js)) {
/* We haven't checked in, so go dump stack. */
print_cpu_stall(rsp);
int i;
struct rcu_data *rdp = __this_cpu_ptr(rsp->rda);
- /*
- * If there is an rcu_barrier() operation in progress, then
- * only the task doing that operation is permitted to adopt
- * callbacks. To do otherwise breaks rcu_barrier() and friends
- * by causing them to fail to wait for the callbacks in the
- * orphanage.
- */
- if (rsp->rcu_barrier_in_progress &&
- rsp->rcu_barrier_in_progress != current)
- return;
-
/* Do the accounting first. */
rdp->qlen_lazy += rsp->qlen_lazy;
rdp->qlen += rsp->qlen;
* The CPU has been completely removed, and some other CPU is reporting
* this fact from process context. Do the remainder of the cleanup,
* including orphaning the outgoing CPU's RCU callbacks, and also
- * adopting them, if there is no _rcu_barrier() instance running.
- * There can only be one CPU hotplug operation at a time, so no other
- * CPU can be attempting to update rcu_cpu_kthread_task.
+ * adopting them. There can only be one CPU hotplug operation at a time,
+ * so no other CPU can be attempting to update rcu_cpu_kthread_task.
*/
static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp)
{
struct rcu_node *rnp = rdp->mynode; /* Outgoing CPU's rdp & rnp. */
/* Adjust any no-longer-needed kthreads. */
- rcu_stop_cpu_kthread(cpu);
- rcu_node_kthread_setaffinity(rnp, -1);
+ rcu_boost_kthread_setaffinity(rnp, -1);
/* Remove the dead CPU from the bitmasks in the rcu_node hierarchy. */
WARN_ONCE(rdp->qlen != 0 || rdp->nxtlist != NULL,
"rcu_cleanup_dead_cpu: Callbacks on offline CPU %d: qlen=%lu, nxtlist=%p\n",
cpu, rdp->qlen, rdp->nxtlist);
+ init_callback_list(rdp);
+ /* Disallow further callbacks on this CPU. */
+ rdp->nxttail[RCU_NEXT_TAIL] = NULL;
}
#else /* #ifdef CONFIG_HOTPLUG_CPU */
-static void rcu_adopt_orphan_cbs(struct rcu_state *rsp)
-{
-}
-
static void rcu_cleanup_dying_cpu(struct rcu_state *rsp)
{
}
head->func = func;
head->next = NULL;
- smp_mb(); /* Ensure RCU update seen before callback registry. */
-
/*
* Opportunistically note grace-period endings and beginnings.
* Note that we might see a beginning right after we see an
rdp = this_cpu_ptr(rsp->rda);
/* Add the callback to our list. */
+ if (unlikely(rdp->nxttail[RCU_NEXT_TAIL] == NULL)) {
+ /* _call_rcu() is illegal on offline CPU; leak the callback. */
+ WARN_ON_ONCE(1);
+ local_irq_restore(flags);
+ return;
+ }
ACCESS_ONCE(rdp->qlen)++;
if (lazy)
rdp->qlen_lazy++;
static void _rcu_barrier(struct rcu_state *rsp)
{
int cpu;
- unsigned long flags;
struct rcu_data *rdp;
- struct rcu_data rd;
unsigned long snap = ACCESS_ONCE(rsp->n_barrier_done);
unsigned long snap_done;
- init_rcu_head_on_stack(&rd.barrier_head);
_rcu_barrier_trace(rsp, "Begin", -1, snap);
/* Take mutex to serialize concurrent rcu_barrier() requests. */
/*
* Initialize the count to one rather than to zero in order to
* avoid a too-soon return to zero in case of a short grace period
- * (or preemption of this task). Also flag this task as doing
- * an rcu_barrier(). This will prevent anyone else from adopting
- * orphaned callbacks, which could cause otherwise failure if a
- * CPU went offline and quickly came back online. To see this,
- * consider the following sequence of events:
- *
- * 1. We cause CPU 0 to post an rcu_barrier_callback() callback.
- * 2. CPU 1 goes offline, orphaning its callbacks.
- * 3. CPU 0 adopts CPU 1's orphaned callbacks.
- * 4. CPU 1 comes back online.
- * 5. We cause CPU 1 to post an rcu_barrier_callback() callback.
- * 6. Both rcu_barrier_callback() callbacks are invoked, awakening
- * us -- but before CPU 1's orphaned callbacks are invoked!!!
+ * (or preemption of this task). Exclude CPU-hotplug operations
+ * to ensure that no offline CPU has callbacks queued.
*/
init_completion(&rsp->barrier_completion);
atomic_set(&rsp->barrier_cpu_count, 1);
- raw_spin_lock_irqsave(&rsp->onofflock, flags);
- rsp->rcu_barrier_in_progress = current;
- raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
+ get_online_cpus();
/*
- * Force every CPU with callbacks to register a new callback
- * that will tell us when all the preceding callbacks have
- * been invoked. If an offline CPU has callbacks, wait for
- * it to either come back online or to finish orphaning those
- * callbacks.
+ * Force each CPU with callbacks to register a new callback.
+ * When that callback is invoked, we will know that all of the
+ * corresponding CPU's preceding callbacks have been invoked.
*/
- for_each_possible_cpu(cpu) {
- preempt_disable();
+ for_each_online_cpu(cpu) {
rdp = per_cpu_ptr(rsp->rda, cpu);
- if (cpu_is_offline(cpu)) {
- _rcu_barrier_trace(rsp, "Offline", cpu,
- rsp->n_barrier_done);
- preempt_enable();
- while (cpu_is_offline(cpu) && ACCESS_ONCE(rdp->qlen))
- schedule_timeout_interruptible(1);
- } else if (ACCESS_ONCE(rdp->qlen)) {
+ if (ACCESS_ONCE(rdp->qlen)) {
_rcu_barrier_trace(rsp, "OnlineQ", cpu,
rsp->n_barrier_done);
smp_call_function_single(cpu, rcu_barrier_func, rsp, 1);
- preempt_enable();
} else {
_rcu_barrier_trace(rsp, "OnlineNQ", cpu,
rsp->n_barrier_done);
- preempt_enable();
}
}
-
- /*
- * Now that all online CPUs have rcu_barrier_callback() callbacks
- * posted, we can adopt all of the orphaned callbacks and place
- * an rcu_barrier_callback() callback after them. When that is done,
- * we are guaranteed to have an rcu_barrier_callback() callback
- * following every callback that could possibly have been
- * registered before _rcu_barrier() was called.
- */
- raw_spin_lock_irqsave(&rsp->onofflock, flags);
- rcu_adopt_orphan_cbs(rsp);
- rsp->rcu_barrier_in_progress = NULL;
- raw_spin_unlock_irqrestore(&rsp->onofflock, flags);
- atomic_inc(&rsp->barrier_cpu_count);
- smp_mb__after_atomic_inc(); /* Ensure atomic_inc() before callback. */
- rd.rsp = rsp;
- rsp->call(&rd.barrier_head, rcu_barrier_callback);
+ put_online_cpus();
/*
* Now that we have an rcu_barrier_callback() callback on each
/* Other rcu_barrier() invocations can now safely proceed. */
mutex_unlock(&rsp->barrier_mutex);
-
- destroy_rcu_head_on_stack(&rd.barrier_head);
}
/**
rdp->dynticks = &per_cpu(rcu_dynticks, cpu);
WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != DYNTICK_TASK_EXIT_IDLE);
WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1);
+#ifdef CONFIG_RCU_USER_QS
+ WARN_ON_ONCE(rdp->dynticks->in_user);
+#endif
rdp->cpu = cpu;
rdp->rsp = rsp;
raw_spin_unlock_irqrestore(&rnp->lock, flags);
rdp->qlen_last_fqs_check = 0;
rdp->n_force_qs_snap = rsp->n_force_qs;
rdp->blimit = blimit;
+ init_callback_list(rdp); /* Re-enable callbacks on this CPU. */
rdp->dynticks->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE;
atomic_set(&rdp->dynticks->dynticks,
(atomic_read(&rdp->dynticks->dynticks) & ~0x1) + 1);
break;
case CPU_ONLINE:
case CPU_DOWN_FAILED:
- rcu_node_kthread_setaffinity(rnp, -1);
- rcu_cpu_kthread_setrt(cpu, 1);
+ rcu_boost_kthread_setaffinity(rnp, -1);
break;
case CPU_DOWN_PREPARE:
- rcu_node_kthread_setaffinity(rnp, cpu);
- rcu_cpu_kthread_setrt(cpu, 0);
+ rcu_boost_kthread_setaffinity(rnp, cpu);
break;
case CPU_DYING:
case CPU_DYING_FROZEN:
int cprv;
int i;
- cprv = NR_CPUS;
+ cprv = nr_cpu_ids;
for (i = rcu_num_lvls - 1; i >= 0; i--) {
ccur = rsp->levelcnt[i];
rsp->levelspread[i] = (cprv + ccur - 1) / ccur;
int rcu_capacity[MAX_RCU_LVLS + 1];
/* If the compile-time values are accurate, just leave. */
- if (rcu_fanout_leaf == CONFIG_RCU_FANOUT_LEAF)
+ if (rcu_fanout_leaf == CONFIG_RCU_FANOUT_LEAF &&
+ nr_cpu_ids == NR_CPUS)
return;
/*
projects / firefly-linux-kernel-4.4.55.git / blobdiff