padata: Use a timer to handle remaining objects in the reorder queues

[safe/jmp/linux-2.6] / kernel / cpu.c

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 79e40f0..25bba73 100644 (file)
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -14,6 +14,7 @@
 #include <linux/kthread.h>
 #include <linux/stop_machine.h>
 #include <linux/mutex.h>
+#include <linux/gfp.h>
 
 #ifdef CONFIG_SMP
 /* Serializes the updates to cpu_online_mask, cpu_present_mask */
@@ -34,14 +35,11 @@ static struct {
         * an ongoing cpu hotplug operation.
         */
        int refcount;
-} cpu_hotplug;
-
-void __init cpu_hotplug_init(void)
-{
-       cpu_hotplug.active_writer = NULL;
-       mutex_init(&cpu_hotplug.lock);
-       cpu_hotplug.refcount = 0;
-}
+} cpu_hotplug = {
+       .active_writer = NULL,
+       .lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
+       .refcount = 0,
+};
 
 #ifdef CONFIG_HOTPLUG_CPU
 
@@ -154,13 +152,13 @@ static inline void check_for_tasks(int cpu)
 
        write_lock_irq(&tasklist_lock);
        for_each_process(p) {
-               if (task_cpu(p) == cpu &&
+               if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
                    (!cputime_eq(p->utime, cputime_zero) ||
                     !cputime_eq(p->stime, cputime_zero)))
-                       printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d\
-                               (state = %ld, flags = %x) \n",
-                                p->comm, task_pid_nr(p), cpu,
-                                p->state, p->flags);
+                       printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d "
+                               "(state = %ld, flags = %x)\n",
+                               p->comm, task_pid_nr(p), cpu,
+                               p->state, p->flags);
        }
        write_unlock_irq(&tasklist_lock);
 }
@@ -212,9 +210,12 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
                return -ENOMEM;
 
        cpu_hotplug_begin();
+       set_cpu_active(cpu, false);
        err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
                                        hcpu, -1, &nr_calls);
        if (err == NOTIFY_BAD) {
+               set_cpu_active(cpu, true);
+
                nr_calls--;
                __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
                                          hcpu, nr_calls, NULL);
@@ -226,11 +227,11 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
 
        /* Ensure that we are not runnable on dying cpu */
        cpumask_copy(old_allowed, &current->cpus_allowed);
-       set_cpus_allowed_ptr(current,
-                            cpumask_of(cpumask_any_but(cpu_online_mask, cpu)));
+       set_cpus_allowed_ptr(current, cpu_active_mask);
 
        err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
        if (err) {
+               set_cpu_active(cpu, true);
                /* CPU didn't die: tell everyone.  Can't complain. */
                if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
                                            hcpu) == NOTIFY_BAD)
@@ -281,23 +282,8 @@ int __ref cpu_down(unsigned int cpu)
                goto out;
        }
 
-       cpu_clear(cpu, cpu_active_map);
-
-       /*
-        * Make sure the all cpus did the reschedule and are not
-        * using stale version of the cpu_active_mask.
-        * This is not strictly necessary becuase stop_machine()
-        * that we run down the line already provides the required
-        * synchronization. But it's really a side effect and we do not
-        * want to depend on the innards of the stop_machine here.
-        */
-       synchronize_sched();
-
        err = _cpu_down(cpu, 0);
 
-       if (cpu_online(cpu))
-               cpu_set(cpu, cpu_active_map);
-
 out:
        cpu_maps_update_done();
        stop_machine_destroy();
@@ -333,7 +319,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
                goto out_notify;
        BUG_ON(!cpu_online(cpu));
 
-       cpu_set(cpu, cpu_active_map);
+       set_cpu_active(cpu, true);
 
        /* Now call notifier in preparation. */
        raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
@@ -353,7 +339,7 @@ int __cpuinit cpu_up(unsigned int cpu)
        if (!cpu_possible(cpu)) {
                printk(KERN_ERR "can't online cpu %d because it is not "
                        "configured as may-hotadd at boot time\n", cpu);
-#if defined(CONFIG_IA64) || defined(CONFIG_X86_64)
+#if defined(CONFIG_IA64)
                printk(KERN_ERR "please check additional_cpus= boot "
                                "parameter\n");
 #endif
@@ -386,24 +372,26 @@ int disable_nonboot_cpus(void)
                return error;
        cpu_maps_update_begin();
        first_cpu = cpumask_first(cpu_online_mask);
-       /* We take down all of the non-boot CPUs in one shot to avoid races
+       /*
+        * We take down all of the non-boot CPUs in one shot to avoid races
         * with the userspace trying to use the CPU hotplug at the same time
         */
        cpumask_clear(frozen_cpus);
+
        printk("Disabling non-boot CPUs ...\n");
        for_each_online_cpu(cpu) {
                if (cpu == first_cpu)
                        continue;
                error = _cpu_down(cpu, 1);
-               if (!error) {
+               if (!error)
                        cpumask_set_cpu(cpu, frozen_cpus);
-                       printk("CPU%d is down\n", cpu);
-               } else {
+               else {
                        printk(KERN_ERR "Error taking CPU%d down: %d\n",
                                cpu, error);
                        break;
                }
        }
+
        if (!error) {
                BUG_ON(num_online_cpus() > 1);
                /* Make sure the CPUs won't be enabled by someone else */
@@ -416,6 +404,14 @@ int disable_nonboot_cpus(void)
        return error;
 }
 
+void __weak arch_enable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_enable_nonboot_cpus_end(void)
+{
+}
+
 void __ref enable_nonboot_cpus(void)
 {
        int cpu, error;
@@ -427,6 +423,9 @@ void __ref enable_nonboot_cpus(void)
                goto out;
 
        printk("Enabling non-boot CPUs ...\n");
+
+       arch_enable_nonboot_cpus_begin();
+
        for_each_cpu(cpu, frozen_cpus) {
                error = _cpu_up(cpu, 1);
                if (!error) {
@@ -435,6 +434,9 @@ void __ref enable_nonboot_cpus(void)
                }
                printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
        }
+
+       arch_enable_nonboot_cpus_end();
+
        cpumask_clear(frozen_cpus);
 out:
        cpu_maps_update_done();