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>
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 28cb6c7..369d2892 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -120,12 +120,13 @@
}
/* Requires cpu_add_remove_lock to be held */
-static int _cpu_down(unsigned int cpu)
+static int _cpu_down(unsigned int cpu, int tasks_frozen)
{
int err, nr_calls = 0;
struct task_struct *p;
cpumask_t old_allowed, tmp;
void *hcpu = (void *)(long)cpu;
+ unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
if (num_online_cpus() == 1)
return -EBUSY;
@@ -134,11 +135,11 @@
return -EINVAL;
raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE, hcpu);
- err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE,
+ err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
hcpu, -1, &nr_calls);
if (err == NOTIFY_BAD) {
- __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED, hcpu,
- nr_calls, NULL);
+ __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
+ hcpu, nr_calls, NULL);
printk("%s: attempt to take down CPU %u failed\n",
__FUNCTION__, cpu);
err = -EINVAL;
@@ -157,7 +158,7 @@
if (IS_ERR(p) || cpu_online(cpu)) {
/* CPU didn't die: tell everyone. Can't complain. */
- if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED,
+ if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
hcpu) == NOTIFY_BAD)
BUG();
@@ -176,7 +177,8 @@
__cpu_die(cpu);
/* CPU is completely dead: tell everyone. Too late to complain. */
- if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD, hcpu) == NOTIFY_BAD)
+ if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD | mod,
+ hcpu) == NOTIFY_BAD)
BUG();
check_for_tasks(cpu);
@@ -186,8 +188,7 @@
out_allowed:
set_cpus_allowed(current, old_allowed);
out_release:
- raw_notifier_call_chain(&cpu_chain, CPU_LOCK_RELEASE,
- (void *)(long)cpu);
+ raw_notifier_call_chain(&cpu_chain, CPU_LOCK_RELEASE, hcpu);
return err;
}
@@ -199,7 +200,7 @@
if (cpu_hotplug_disabled)
err = -EBUSY;
else
- err = _cpu_down(cpu);
+ err = _cpu_down(cpu, 0);
mutex_unlock(&cpu_add_remove_lock);
return err;
@@ -207,16 +208,17 @@
#endif /*CONFIG_HOTPLUG_CPU*/
/* Requires cpu_add_remove_lock to be held */
-static int __cpuinit _cpu_up(unsigned int cpu)
+static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
{
int ret, nr_calls = 0;
void *hcpu = (void *)(long)cpu;
+ unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
if (cpu_online(cpu) || !cpu_present(cpu))
return -EINVAL;
raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE, hcpu);
- ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE, hcpu,
+ ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu,
-1, &nr_calls);
if (ret == NOTIFY_BAD) {
printk("%s: attempt to bring up CPU %u failed\n",
@@ -234,12 +236,12 @@
BUG_ON(!cpu_online(cpu));
/* Now call notifier in preparation. */
- raw_notifier_call_chain(&cpu_chain, CPU_ONLINE, hcpu);
+ raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
out_notify:
if (ret != 0)
__raw_notifier_call_chain(&cpu_chain,
- CPU_UP_CANCELED, hcpu, nr_calls, NULL);
+ CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
raw_notifier_call_chain(&cpu_chain, CPU_LOCK_RELEASE, hcpu);
return ret;
@@ -253,7 +255,7 @@
if (cpu_hotplug_disabled)
err = -EBUSY;
else
- err = _cpu_up(cpu);
+ err = _cpu_up(cpu, 0);
mutex_unlock(&cpu_add_remove_lock);
return err;
@@ -283,7 +285,7 @@
for_each_online_cpu(cpu) {
if (cpu == first_cpu)
continue;
- error = _cpu_down(cpu);
+ error = _cpu_down(cpu, 1);
if (!error) {
cpu_set(cpu, frozen_cpus);
printk("CPU%d is down\n", cpu);
@@ -318,7 +320,7 @@
suspend_cpu_hotplug = 1;
printk("Enabling non-boot CPUs ...\n");
for_each_cpu_mask(cpu, frozen_cpus) {
- error = _cpu_up(cpu);
+ error = _cpu_up(cpu, 1);
if (!error) {
printk("CPU%d is up\n", cpu);
continue;