Add suspend-related notifications for CPU hotplug

Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 19 insertions, 0 deletions

diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index 067a9e8bc37..8d8cdfec652 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -126,10 +126,13 @@ static int __cpuinit topology_cpu_callback(struct notifier_block *nfb,
 
 	switch (action) {
 	case CPU_UP_PREPARE:
+	case CPU_UP_PREPARE_FROZEN:
 		rc = topology_add_dev(cpu);
 		break;
 	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
 	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
 		topology_remove_dev(cpu);
 		break;
 	}
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 893dbaf386f..eb37fba9b7e 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1685,9 +1685,11 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb,
 	if (sys_dev) {
 		switch (action) {
 		case CPU_ONLINE:
+		case CPU_ONLINE_FROZEN:
 			cpufreq_add_dev(sys_dev);
 			break;
 		case CPU_DOWN_PREPARE:
+		case CPU_DOWN_PREPARE_FROZEN:
 			if (unlikely(lock_policy_rwsem_write(cpu)))
 				BUG();
 
@@ -1699,6 +1701,7 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb,
 			__cpufreq_remove_dev(sys_dev);
 			break;
 		case CPU_DOWN_FAILED:
+		case CPU_DOWN_FAILED_FROZEN:
 			cpufreq_add_dev(sys_dev);
 			break;
 		}
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index d1c7cac9316..d2f0cbd8b8f 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -313,9 +313,11 @@ static int cpufreq_stat_cpu_callback(struct notifier_block *nfb,
 
 	switch (action) {
 	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
 		cpufreq_update_policy(cpu);
 		break;
 	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
 		cpufreq_stats_free_table(cpu);
 		break;
 	}
diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index 03b1f650d1c..75e3911810a 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -309,9 +309,11 @@ static int coretemp_cpu_callback(struct notifier_block *nfb,
 
 	switch (action) {
 	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
 		coretemp_device_add(cpu);
 		break;
 	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
 		coretemp_device_remove(cpu);
 		break;
 	}
diff --git a/drivers/infiniband/hw/ehca/ehca_irq.c b/drivers/infiniband/hw/ehca/ehca_irq.c
index f284be1c916..82dda2faf4d 100644
--- a/drivers/infiniband/hw/ehca/ehca_irq.c
+++ b/drivers/infiniband/hw/ehca/ehca_irq.c
@@ -745,6 +745,7 @@ static int comp_pool_callback(struct notifier_block *nfb,
 
 	switch (action) {
 	case CPU_UP_PREPARE:
+	case CPU_UP_PREPARE_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_PREPARE)", cpu);
 		if(!create_comp_task(pool, cpu)) {
 			ehca_gen_err("Can't create comp_task for cpu: %x", cpu);
@@ -752,24 +753,29 @@ static int comp_pool_callback(struct notifier_block *nfb,
 		}
 		break;
 	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_CANCELED)", cpu);
 		cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 		kthread_bind(cct->task, any_online_cpu(cpu_online_map));
 		destroy_comp_task(pool, cpu);
 		break;
 	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_ONLINE)", cpu);
 		cct = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
 		kthread_bind(cct->task, cpu);
 		wake_up_process(cct->task);
 		break;
 	case CPU_DOWN_PREPARE:
+	case CPU_DOWN_PREPARE_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_DOWN_PREPARE)", cpu);
 		break;
 	case CPU_DOWN_FAILED:
+	case CPU_DOWN_FAILED_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_DOWN_FAILED)", cpu);
 		break;
 	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
 		ehca_gen_dbg("CPU: %x (CPU_DEAD)", cpu);
 		destroy_comp_task(pool, cpu);
 		take_over_work(pool, cpu);
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index c8b8cfa332b..0d892600ff0 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -2889,7 +2889,9 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
 
 	switch (val) {
 	case CPU_DOWN_PREPARE:
+	case CPU_DOWN_PREPARE_FROZEN:
 	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
 		printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
 		       cpu);
 		decache_vcpus_on_cpu(cpu);
@@ -2897,6 +2899,7 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
 					 NULL, 0, 1);
 		break;
 	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
 		printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
 		       cpu);
 		smp_call_function_single(cpu, kvm_arch_ops->hardware_enable,