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Diffstat (limited to 'kernel/cpu.c')
-rw-r--r--kernel/cpu.c100
1 files changed, 83 insertions, 17 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 3e3f6e49eabb..341bf80f80bd 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -517,6 +517,13 @@ static int cpuhp_invoke_ap_callback(int cpu, enum cpuhp_state state,
if (!cpu_online(cpu))
return 0;
+ /*
+ * If we are up and running, use the hotplug thread. For early calls
+ * we invoke the thread function directly.
+ */
+ if (!st->thread)
+ return cpuhp_invoke_callback(cpu, state, cb);
+
st->cb_state = state;
st->cb = cb;
/*
@@ -703,21 +710,6 @@ static int takedown_cpu(unsigned int cpu)
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
int err;
- /*
- * By now we've cleared cpu_active_mask, wait for all preempt-disabled
- * and RCU users of this state to go away such that all new such users
- * will observe it.
- *
- * For CONFIG_PREEMPT we have preemptible RCU and its sync_rcu() might
- * not imply sync_sched(), so wait for both.
- *
- * Do sync before park smpboot threads to take care the rcu boost case.
- */
- if (IS_ENABLED(CONFIG_PREEMPT))
- synchronize_rcu_mult(call_rcu, call_rcu_sched);
- else
- synchronize_rcu();
-
/* Park the smpboot threads */
kthread_park(per_cpu_ptr(&cpuhp_state, cpu)->thread);
smpboot_park_threads(cpu);
@@ -923,8 +915,6 @@ void cpuhp_online_idle(enum cpuhp_state state)
st->state = CPUHP_AP_ONLINE_IDLE;
- /* The cpu is marked online, set it active now */
- set_cpu_active(cpu, true);
/* Unpark the stopper thread and the hotplug thread of this cpu */
stop_machine_unpark(cpu);
kthread_unpark(st->thread);
@@ -1190,6 +1180,31 @@ static struct cpuhp_step cpuhp_bp_states[] = {
.teardown = NULL,
.cant_stop = true,
},
+ [CPUHP_PERF_PREPARE] = {
+ .name = "perf prepare",
+ .startup = perf_event_init_cpu,
+ .teardown = perf_event_exit_cpu,
+ },
+ [CPUHP_WORKQUEUE_PREP] = {
+ .name = "workqueue prepare",
+ .startup = workqueue_prepare_cpu,
+ .teardown = NULL,
+ },
+ [CPUHP_HRTIMERS_PREPARE] = {
+ .name = "hrtimers prepare",
+ .startup = hrtimers_prepare_cpu,
+ .teardown = hrtimers_dead_cpu,
+ },
+ [CPUHP_SMPCFD_PREPARE] = {
+ .name = "SMPCFD prepare",
+ .startup = smpcfd_prepare_cpu,
+ .teardown = smpcfd_dead_cpu,
+ },
+ [CPUHP_RCUTREE_PREP] = {
+ .name = "RCU-tree prepare",
+ .startup = rcutree_prepare_cpu,
+ .teardown = rcutree_dead_cpu,
+ },
/*
* Preparatory and dead notifiers. Will be replaced once the notifiers
* are converted to states.
@@ -1201,6 +1216,16 @@ static struct cpuhp_step cpuhp_bp_states[] = {
.skip_onerr = true,
.cant_stop = true,
},
+ /*
+ * On the tear-down path, timers_dead_cpu() must be invoked
+ * before blk_mq_queue_reinit_notify() from notify_dead(),
+ * otherwise a RCU stall occurs.
+ */
+ [CPUHP_TIMERS_DEAD] = {
+ .name = "timers dead",
+ .startup = NULL,
+ .teardown = timers_dead_cpu,
+ },
/* Kicks the plugged cpu into life */
[CPUHP_BRINGUP_CPU] = {
.name = "cpu:bringup",
@@ -1208,6 +1233,10 @@ static struct cpuhp_step cpuhp_bp_states[] = {
.teardown = NULL,
.cant_stop = true,
},
+ [CPUHP_AP_SMPCFD_DYING] = {
+ .startup = NULL,
+ .teardown = smpcfd_dying_cpu,
+ },
/*
* Handled on controll processor until the plugged processor manages
* this itself.
@@ -1218,6 +1247,8 @@ static struct cpuhp_step cpuhp_bp_states[] = {
.teardown = takedown_cpu,
.cant_stop = true,
},
+#else
+ [CPUHP_BRINGUP_CPU] = { },
#endif
};
@@ -1236,6 +1267,16 @@ static struct cpuhp_step cpuhp_ap_states[] = {
.name = "ap:offline",
.cant_stop = true,
},
+ /* First state is scheduler control. Interrupts are disabled */
+ [CPUHP_AP_SCHED_STARTING] = {
+ .name = "sched:starting",
+ .startup = sched_cpu_starting,
+ .teardown = sched_cpu_dying,
+ },
+ [CPUHP_AP_RCUTREE_DYING] = {
+ .startup = NULL,
+ .teardown = rcutree_dying_cpu,
+ },
/*
* Low level startup/teardown notifiers. Run with interrupts
* disabled. Will be removed once the notifiers are converted to
@@ -1259,6 +1300,22 @@ static struct cpuhp_step cpuhp_ap_states[] = {
.startup = smpboot_unpark_threads,
.teardown = NULL,
},
+ [CPUHP_AP_PERF_ONLINE] = {
+ .name = "perf online",
+ .startup = perf_event_init_cpu,
+ .teardown = perf_event_exit_cpu,
+ },
+ [CPUHP_AP_WORKQUEUE_ONLINE] = {
+ .name = "workqueue online",
+ .startup = workqueue_online_cpu,
+ .teardown = workqueue_offline_cpu,
+ },
+ [CPUHP_AP_RCUTREE_ONLINE] = {
+ .name = "RCU-tree online",
+ .startup = rcutree_online_cpu,
+ .teardown = rcutree_offline_cpu,
+ },
+
/*
* Online/down_prepare notifiers. Will be removed once the notifiers
* are converted to states.
@@ -1274,6 +1331,15 @@ static struct cpuhp_step cpuhp_ap_states[] = {
* The dynamically registered state space is here
*/
+#ifdef CONFIG_SMP
+ /* Last state is scheduler control setting the cpu active */
+ [CPUHP_AP_ACTIVE] = {
+ .name = "sched:active",
+ .startup = sched_cpu_activate,
+ .teardown = sched_cpu_deactivate,
+ },
+#endif
+
/* CPU is fully up and running. */
[CPUHP_ONLINE] = {
.name = "online",