From: Rafael J. Wysocki <[email protected]> To separate the CPU online interface from the CPU device removal one, split cpufreq_online() out of cpufreq_add_dev() and make cpufreq_cpu_callback() call the former, while the latter will only be used as the CPU device removal subsystem interface callback.
While at it, notice that the return value of sif->add_dev() is ignored in bus_probe_device(), so (the new) cpufreq_add_dev() doesn't need to bother with returning anything different from 0 and cpufreq_online() may be a void function. Moreover, since the return value of cpufreq_add_policy_cpu() is going to be ignored now too, make a void function of it as well. Signed-off-by: Rafael J. Wysocki <[email protected]> Suggested-by: Russell King <[email protected]> --- drivers/cpufreq/cpufreq.c | 125 ++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 64 deletions(-) Index: linux-pm/drivers/cpufreq/cpufreq.c =================================================================== --- linux-pm.orig/drivers/cpufreq/cpufreq.c +++ linux-pm/drivers/cpufreq/cpufreq.c @@ -1056,19 +1056,17 @@ static int cpufreq_init_policy(struct cp return cpufreq_set_policy(policy, &new_policy); } -static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) +static void cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) { - int ret = 0; - /* Has this CPU been taken care of already? */ if (cpumask_test_cpu(cpu, policy->cpus)) - return 0; + return; if (has_target()) { - ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); + int ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); if (ret) { pr_err("%s: Failed to stop governor\n", __func__); - return ret; + return; } } @@ -1077,17 +1075,13 @@ static int cpufreq_add_policy_cpu(struct up_write(&policy->rwsem); if (has_target()) { - ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); + int ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); if (!ret) ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); - if (ret) { + if (ret) pr_err("%s: Failed to start governor\n", __func__); - return ret; - } } - - return 0; } static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) @@ -1191,44 +1185,24 @@ static void cpufreq_policy_free(struct c kfree(policy); } -/** - * cpufreq_add_dev - add a CPU device - * - * Adds the cpufreq interface for a CPU device. - * - * The Oracle says: try running cpufreq registration/unregistration concurrently - * with with cpu hotplugging and all hell will break loose. Tried to clean this - * mess up, but more thorough testing is needed. - Mathieu - */ -static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) +static void cpufreq_online(unsigned int cpu) { - unsigned int j, cpu = dev->id; - int ret = -ENOMEM; struct cpufreq_policy *policy; - unsigned long flags; bool recover_policy; + unsigned long flags; + unsigned int j; + int ret; - pr_debug("adding CPU %u\n", cpu); - - if (cpu_is_offline(cpu)) { - /* - * Only possible if we are here from the subsys_interface add - * callback. A hotplug notifier will follow and we will handle - * it as CPU online then. For now, just create the sysfs link, - * unless there is no policy or the link is already present. - */ - policy = per_cpu(cpufreq_cpu_data, cpu); - return policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) - ? add_cpu_dev_symlink(policy, cpu) : 0; - } + pr_debug("%s: bringing CPU%u online\n", __func__, cpu); /* Check if this CPU already has a policy to manage it */ policy = per_cpu(cpufreq_cpu_data, cpu); if (policy) { WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); - if (!policy_is_inactive(policy)) - return cpufreq_add_policy_cpu(policy, cpu); - + if (!policy_is_inactive(policy)) { + cpufreq_add_policy_cpu(policy, cpu); + return; + } /* This is the only online CPU for the policy. Start over. */ recover_policy = true; down_write(&policy->rwsem); @@ -1239,7 +1213,7 @@ static int cpufreq_add_dev(struct device recover_policy = false; policy = cpufreq_policy_alloc(cpu); if (!policy) - return -ENOMEM; + return; } cpumask_copy(policy->cpus, cpumask_of(cpu)); @@ -1362,7 +1336,7 @@ static int cpufreq_add_dev(struct device pr_debug("initialization complete\n"); - return 0; + return; out_remove_policy_notify: /* cpufreq_policy_free() will notify based on this */ @@ -1374,7 +1348,34 @@ out_exit_policy: cpufreq_driver->exit(policy); out_free_policy: cpufreq_policy_free(policy, recover_policy); - return ret; +} + +/** + * cpufreq_add_dev - the cpufreq interface for a CPU device. + * @dev: CPU device. + * @sif: Subsystem interface structure pointer (not used) + */ +static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) +{ + unsigned cpu = dev->id; + + dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); + + if (cpu_online(cpu)) { + cpufreq_online(cpu); + } else { + /* + * A hotplug notifier will follow and we will handle it as CPU + * online then. For now, just create the sysfs link, unless + * there is no policy or the link is already present. + */ + struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); + + if (policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus)) + WARN_ON(add_cpu_dev_symlink(policy, cpu)); + } + + return 0; } static void cpufreq_offline_prepare(unsigned int cpu) @@ -2340,27 +2341,23 @@ static int cpufreq_cpu_callback(struct n unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; - struct device *dev; - dev = get_cpu_device(cpu); - if (dev) { - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_ONLINE: - cpufreq_add_dev(dev, NULL); - break; - - case CPU_DOWN_PREPARE: - cpufreq_offline_prepare(cpu); - break; - - case CPU_POST_DEAD: - cpufreq_offline_finish(cpu); - break; - - case CPU_DOWN_FAILED: - cpufreq_add_dev(dev, NULL); - break; - } + switch (action & ~CPU_TASKS_FROZEN) { + case CPU_ONLINE: + cpufreq_online(cpu); + break; + + case CPU_DOWN_PREPARE: + cpufreq_offline_prepare(cpu); + break; + + case CPU_POST_DEAD: + cpufreq_offline_finish(cpu); + break; + + case CPU_DOWN_FAILED: + cpufreq_online(cpu); + break; } return NOTIFY_OK; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
