Merge branch 'from-linus' into upstream
[powerpc.git] / drivers / cpufreq / cpufreq.c
index cb7d6e0..29b2fa5 100644 (file)
@@ -6,6 +6,8 @@
  *
  *  Oct 2005 - Ashok Raj <ashok.raj@intel.com>
  *     Added handling for CPU hotplug
+ *  Feb 2006 - Jacob Shin <jacob.shin@amd.com>
+ *     Fix handling for CPU hotplug -- affected CPUs
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -50,9 +52,8 @@ static void handle_update(void *data);
  * changes to devices when the CPU clock speed changes.
  * The mutex locks both lists.
  */
-static struct notifier_block *cpufreq_policy_notifier_list;
-static struct notifier_block *cpufreq_transition_notifier_list;
-static DECLARE_RWSEM (cpufreq_notifier_rwsem);
+static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
+static BLOCKING_NOTIFIER_HEAD(cpufreq_transition_notifier_list);
 
 
 static LIST_HEAD(cpufreq_governor_list);
@@ -245,8 +246,6 @@ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
        dprintk("notification %u of frequency transition to %u kHz\n",
                state, freqs->new);
 
-       down_read(&cpufreq_notifier_rwsem);
-
        policy = cpufreq_cpu_data[freqs->cpu];
        switch (state) {
 
@@ -264,20 +263,19 @@ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
                                freqs->old = policy->cur;
                        }
                }
-               notifier_call_chain(&cpufreq_transition_notifier_list,
-                                       CPUFREQ_PRECHANGE, freqs);
+               blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
+                               CPUFREQ_PRECHANGE, freqs);
                adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
                break;
 
        case CPUFREQ_POSTCHANGE:
                adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
-               notifier_call_chain(&cpufreq_transition_notifier_list,
-                                       CPUFREQ_POSTCHANGE, freqs);
+               blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
+                               CPUFREQ_POSTCHANGE, freqs);
                if (likely(policy) && likely(policy->cpu == freqs->cpu))
                        policy->cur = freqs->new;
                break;
        }
-       up_read(&cpufreq_notifier_rwsem);
 }
 EXPORT_SYMBOL_GPL(cpufreq_notify_transition);
 
@@ -321,7 +319,6 @@ out:
        }
        return -EINVAL;
 }
-EXPORT_SYMBOL_GPL(cpufreq_parse_governor);
 
 
 /* drivers/base/cpu.c */
@@ -348,6 +345,8 @@ show_one(scaling_min_freq, min);
 show_one(scaling_max_freq, max);
 show_one(scaling_cur_freq, cur);
 
+static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_policy *policy);
+
 /**
  * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
  */
@@ -366,7 +365,10 @@ static ssize_t store_##file_name                                   \
        if (ret != 1)                                                   \
                return -EINVAL;                                         \
                                                                        \
-       ret = cpufreq_set_policy(&new_policy);                          \
+       mutex_lock(&policy->lock);                                      \
+       ret = __cpufreq_set_policy(policy, &new_policy);                \
+       policy->user_policy.object = policy->object;                    \
+       mutex_unlock(&policy->lock);                                    \
                                                                        \
        return ret ? ret : count;                                       \
 }
@@ -422,7 +424,15 @@ static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
        if (cpufreq_parse_governor(str_governor, &new_policy.policy, &new_policy.governor))
                return -EINVAL;
 
-       ret = cpufreq_set_policy(&new_policy);
+       /* Do not use cpufreq_set_policy here or the user_policy.max
+          will be wrongly overridden */
+       mutex_lock(&policy->lock);
+       ret = __cpufreq_set_policy(policy, &new_policy);
+
+       policy->user_policy.policy = policy->policy;
+       policy->user_policy.governor = policy->governor;
+       mutex_unlock(&policy->lock);
+
        return ret ? ret : count;
 }
 
@@ -573,8 +583,12 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
        struct cpufreq_policy new_policy;
        struct cpufreq_policy *policy;
        struct freq_attr **drv_attr;
+       struct sys_device *cpu_sys_dev;
        unsigned long flags;
        unsigned int j;
+#ifdef CONFIG_SMP
+       struct cpufreq_policy *managed_policy;
+#endif
 
        if (cpu_is_offline(cpu))
                return 0;
@@ -587,8 +601,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
         * CPU because it is in the same boat. */
        policy = cpufreq_cpu_get(cpu);
        if (unlikely(policy)) {
-               dprintk("CPU already managed, adding link\n");
-               sysfs_create_link(&sys_dev->kobj, &policy->kobj, "cpufreq");
+               cpufreq_cpu_put(policy);
                cpufreq_debug_enable_ratelimit();
                return 0;
        }
@@ -623,6 +636,32 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
                goto err_out;
        }
 
+#ifdef CONFIG_SMP
+       for_each_cpu_mask(j, policy->cpus) {
+               if (cpu == j)
+                       continue;
+
+               /* check for existing affected CPUs.  They may not be aware
+                * of it due to CPU Hotplug.
+                */
+               managed_policy = cpufreq_cpu_get(j);
+               if (unlikely(managed_policy)) {
+                       spin_lock_irqsave(&cpufreq_driver_lock, flags);
+                       managed_policy->cpus = policy->cpus;
+                       cpufreq_cpu_data[cpu] = managed_policy;
+                       spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+                       dprintk("CPU already managed, adding link\n");
+                       sysfs_create_link(&sys_dev->kobj,
+                                         &managed_policy->kobj, "cpufreq");
+
+                       cpufreq_debug_enable_ratelimit();
+                       mutex_unlock(&policy->lock);
+                       ret = 0;
+                       goto err_out_driver_exit; /* call driver->exit() */
+               }
+       }
+#endif
        memcpy(&new_policy, policy, sizeof(struct cpufreq_policy));
 
        /* prepare interface data */
@@ -650,12 +689,26 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
        for_each_cpu_mask(j, policy->cpus)
                cpufreq_cpu_data[j] = policy;
        spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+       /* symlink affected CPUs */
+       for_each_cpu_mask(j, policy->cpus) {
+               if (j == cpu)
+                       continue;
+               if (!cpu_online(j))
+                       continue;
+
+               dprintk("CPU %u already managed, adding link\n", j);
+               cpufreq_cpu_get(cpu);
+               cpu_sys_dev = get_cpu_sysdev(j);
+               sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
+                                 "cpufreq");
+       }
+
        policy->governor = NULL; /* to assure that the starting sequence is
                                  * run in cpufreq_set_policy */
        mutex_unlock(&policy->lock);
-       
+
        /* set default policy */
-       
        ret = cpufreq_set_policy(&new_policy);
        if (ret) {
                dprintk("setting policy failed\n");
@@ -665,7 +718,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
        module_put(cpufreq_driver->owner);
        dprintk("initialization complete\n");
        cpufreq_debug_enable_ratelimit();
-       
+
        return 0;
 
 
@@ -728,6 +781,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
         */
        if (unlikely(cpu != data->cpu)) {
                dprintk("removing link\n");
+               cpu_clear(cpu, data->cpus);
                spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
                sysfs_remove_link(&sys_dev->kobj, "cpufreq");
                cpufreq_cpu_put(data);
@@ -960,7 +1014,7 @@ static int cpufreq_suspend(struct sys_device * sysdev, pm_message_t pmsg)
                freqs.old = cpu_policy->cur;
                freqs.new = cur_freq;
 
-               notifier_call_chain(&cpufreq_transition_notifier_list,
+               blocking_notifier_call_chain(&cpufreq_transition_notifier_list,
                                    CPUFREQ_SUSPENDCHANGE, &freqs);
                adjust_jiffies(CPUFREQ_SUSPENDCHANGE, &freqs);
 
@@ -1041,7 +1095,8 @@ static int cpufreq_resume(struct sys_device * sysdev)
                        freqs.old = cpu_policy->cur;
                        freqs.new = cur_freq;
 
-                       notifier_call_chain(&cpufreq_transition_notifier_list,
+                       blocking_notifier_call_chain(
+                                       &cpufreq_transition_notifier_list,
                                        CPUFREQ_RESUMECHANGE, &freqs);
                        adjust_jiffies(CPUFREQ_RESUMECHANGE, &freqs);
 
@@ -1078,24 +1133,24 @@ static struct sysdev_driver cpufreq_sysdev_driver = {
  *      changes in cpufreq policy.
  *
  *     This function may sleep, and has the same return conditions as
- *     notifier_chain_register.
+ *     blocking_notifier_chain_register.
  */
 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
 {
        int ret;
 
-       down_write(&cpufreq_notifier_rwsem);
        switch (list) {
        case CPUFREQ_TRANSITION_NOTIFIER:
-               ret = notifier_chain_register(&cpufreq_transition_notifier_list, nb);
+               ret = blocking_notifier_chain_register(
+                               &cpufreq_transition_notifier_list, nb);
                break;
        case CPUFREQ_POLICY_NOTIFIER:
-               ret = notifier_chain_register(&cpufreq_policy_notifier_list, nb);
+               ret = blocking_notifier_chain_register(
+                               &cpufreq_policy_notifier_list, nb);
                break;
        default:
                ret = -EINVAL;
        }
-       up_write(&cpufreq_notifier_rwsem);
 
        return ret;
 }
@@ -1110,24 +1165,24 @@ EXPORT_SYMBOL(cpufreq_register_notifier);
  *     Remove a driver from the CPU frequency notifier list.
  *
  *     This function may sleep, and has the same return conditions as
- *     notifier_chain_unregister.
+ *     blocking_notifier_chain_unregister.
  */
 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
 {
        int ret;
 
-       down_write(&cpufreq_notifier_rwsem);
        switch (list) {
        case CPUFREQ_TRANSITION_NOTIFIER:
-               ret = notifier_chain_unregister(&cpufreq_transition_notifier_list, nb);
+               ret = blocking_notifier_chain_unregister(
+                               &cpufreq_transition_notifier_list, nb);
                break;
        case CPUFREQ_POLICY_NOTIFIER:
-               ret = notifier_chain_unregister(&cpufreq_policy_notifier_list, nb);
+               ret = blocking_notifier_chain_unregister(
+                               &cpufreq_policy_notifier_list, nb);
                break;
        default:
                ret = -EINVAL;
        }
-       up_write(&cpufreq_notifier_rwsem);
 
        return ret;
 }
@@ -1299,29 +1354,23 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data, struct cpufreq_poli
        if (ret)
                goto error_out;
 
-       down_read(&cpufreq_notifier_rwsem);
-
        /* adjust if necessary - all reasons */
-       notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_ADJUST,
-                           policy);
+       blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                       CPUFREQ_ADJUST, policy);
 
        /* adjust if necessary - hardware incompatibility*/
-       notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_INCOMPATIBLE,
-                           policy);
+       blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                       CPUFREQ_INCOMPATIBLE, policy);
 
        /* verify the cpu speed can be set within this limit,
           which might be different to the first one */
        ret = cpufreq_driver->verify(policy);
-       if (ret) {
-               up_read(&cpufreq_notifier_rwsem);
+       if (ret)
                goto error_out;
-       }
 
        /* notification of the new policy */
-       notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_NOTIFY,
-                           policy);
-
-       up_read(&cpufreq_notifier_rwsem);
+       blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+                       CPUFREQ_NOTIFY, policy);
 
        data->min = policy->min;
        data->max = policy->max;
@@ -1448,7 +1497,7 @@ int cpufreq_update_policy(unsigned int cpu)
 }
 EXPORT_SYMBOL(cpufreq_update_policy);
 
-static int __cpuinit cpufreq_cpu_callback(struct notifier_block *nfb,
+static int cpufreq_cpu_callback(struct notifier_block *nfb,
                                        unsigned long action, void *hcpu)
 {
        unsigned int cpu = (unsigned long)hcpu;