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Subject: Re: [PATCH 4/8] cppc_cpufreq: replace per-cpu structures with lists
To:     Ionela Voinescu <ionela.voinescu@arm.com>, rjw@rjwysocki.net,
        viresh.kumar@linaro.org, lenb@kernel.org, sudeep.holla@arm.com
Cc:     morten.rasmussen@arm.com, linux-pm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20201105125524.4409-1-ionela.voinescu@arm.com>
 <20201105125524.4409-5-ionela.voinescu@arm.com>
From:   Jeremy Linton <jeremy.linton@arm.com>
Message-ID: <e568847d-b15c-970c-6ad5-b431c81c811c@arm.com>
Date:   Thu, 5 Nov 2020 09:50:30 -0600
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Hi,

On 11/5/20 6:55 AM, Ionela Voinescu wrote:
> The cppc_cpudata per-cpu storage was inefficient (1) additional to causing
> functional issues (2) when CPUs are hotplugged out, due to per-cpu data
> being improperly initialised.
> 
> (1) The amount of information needed for CPPC performance control in its
>      cpufreq driver depends on the domain (PSD) coordination type:
> 
>      ANY:    One set of CPPC control and capability data (e.g desired
>              performance, highest/lowest performance, etc) applies to all
>              CPUs in the domain.
> 
>      ALL:    Same as ANY. To be noted that this type is not currently
>              supported. When supported, information about which CPUs
>              belong to a domain is needed in order for frequency change
>              requests to be sent to each of them.
> 
>      HW:     It's necessary to store CPPC control and capability
>              information for all the CPUs. HW will then coordinate the
>              performance state based on their limitations and requests.
> 
>      NONE:   Same as HW. No HW coordination is expected.
> 
>      Despite this, the previous initialisation code would indiscriminately
>      allocate memory for all CPUs (all_cpu_data) and unnecessarily
>      duplicate performance capabilities and the domain sharing mask and type
>      for each possible CPU.

I should have mentioned this on the last set.

If the common case on arm/acpi machines is a single core per _PSD (which 
I believe it is), then you are actually increasing the overhead doing this.

> 
> (2) With the current per-cpu structure, when having ANY coordination,
>      the cppc_cpudata cpu information is not initialised (will remain 0)
>      for all CPUs in a policy, other than policy->cpu. When policy->cpu is
>      hotplugged out, the driver will incorrectly use the uninitialised (0)
>      value of the other CPUs when making frequency changes. Additionally,
>      the previous values stored in the perf_ctrls.desired_perf will be
>      lost when policy->cpu changes.
> 
> Due to the current storage of driver data not being fit for purpose,
> replace the per-cpu CPPC/PSD data with a list of domains which in turn
> will point to a list of CPUs with their controls and capabilities,
> belonging to the domain.
> 
> This new structure has the following benefits:
>   - Clearly separates PSD (domain) data from CPPC (performance monitoring
>     and control) data and stores one mask of CPUs belonging to a domain
>     and its type in a single structure, for each domain.
> 
>   - For ANY domain coordination, a single cppc_cpudata set of capabilities
>     and controls are stored, for policy->cpu, and used for describing
>     performance controls and capabilities even when policy->cpu changes as
>     a result of hotplug. All the CPUs in the domain will belong to the
>     same policy.
> 
>   - For HW or lack of coordination, a full map of domains and CPUs is
>     obtained. Each CPU will have its own policy, but for HW, as a result
>     of PSD information, a shared_cpu_map mask could be used to identify
>     the domain CPU content.
> 
> Additional changes:
> 
>   - A pointer to the policy's cppc_cpudata is stored in policy->driver_data
> 
>   - All data allocation is done from the driver's init function. At that
>     point the domain is either created or retrieved. For this purpose
>     acpi_get_psd_map() was changed to create a map of the domain of a
>     single CPU, rather than the full system domain map.
> 
>   - When CPU's are hotplugged out and in, old information can be retrieved.
> 
> Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
> Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
> Cc: Len Brown <lenb@kernel.org>
> Cc: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>   drivers/acpi/cppc_acpi.c       | 126 +++++++------------
>   drivers/cpufreq/cppc_cpufreq.c | 217 ++++++++++++++++++++-------------
>   include/acpi/cppc_acpi.h       |  14 ++-
>   3 files changed, 190 insertions(+), 167 deletions(-)
> 
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 7a99b19bb893..75e36b909ae6 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -414,108 +414,72 @@ static int acpi_get_psd(struct cpc_desc *cpc_ptr, acpi_handle handle)
>   }
>   
>   /**
> - * acpi_get_psd_map - Map the CPUs in a common freq domain.
> - * @all_cpu_data: Ptrs to CPU specific CPPC data including PSD info.
> + * acpi_get_psd_map - Map the CPUs in the freq domain of a given cpu
> + * @cpu: Find all CPUs that share a domain with cpu.
> + * @domain: Pointer to given domain data storage
>    *
>    *	Return: 0 for success or negative value for err.
>    */
> -int acpi_get_psd_map(struct cppc_cpudata **all_cpu_data)
> +int acpi_get_psd_map(unsigned int cpu, struct psd_data *domain)
>   {
> -	int count_target;
> -	int retval = 0;
> -	unsigned int i, j;
> -	cpumask_var_t covered_cpus;
> -	struct cppc_cpudata *pr, *match_pr;
> -	struct acpi_psd_package *pdomain;
> -	struct acpi_psd_package *match_pdomain;
>   	struct cpc_desc *cpc_ptr, *match_cpc_ptr;
> -
> -	if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
> -		return -ENOMEM;
> +	struct acpi_psd_package *match_pdomain;
> +	struct acpi_psd_package *pdomain;
> +	int count_target, i;
>   
>   	/*
>   	 * Now that we have _PSD data from all CPUs, let's setup P-state
>   	 * domain info.
>   	 */
> -	for_each_possible_cpu(i) {
> -		if (cpumask_test_cpu(i, covered_cpus))
> -			continue;
> +	cpc_ptr = per_cpu(cpc_desc_ptr, cpu);
> +	if (!cpc_ptr)
> +		return -EFAULT;
>   
> -		pr = all_cpu_data[i];
> -		cpc_ptr = per_cpu(cpc_desc_ptr, i);
> -		if (!cpc_ptr) {
> -			retval = -EFAULT;
> -			goto err_ret;
> -		}
> +	pdomain = &(cpc_ptr->domain_info);
> +	cpumask_set_cpu(cpu, domain->shared_cpu_map);
> +	if (pdomain->num_processors <= 1)
> +		return 0;
>   
> -		pdomain = &(cpc_ptr->domain_info);
> -		cpumask_set_cpu(i, pr->shared_cpu_map);
> -		cpumask_set_cpu(i, covered_cpus);
> -		if (pdomain->num_processors <= 1)
> -			continue;
> +	/* Validate the Domain info */
> +	count_target = pdomain->num_processors;
> +	if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
> +		domain->shared_type = CPUFREQ_SHARED_TYPE_ALL;
> +	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
> +		domain->shared_type = CPUFREQ_SHARED_TYPE_HW;
> +	else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
> +		domain->shared_type = CPUFREQ_SHARED_TYPE_ANY;
>   
> -		/* Validate the Domain info */
> -		count_target = pdomain->num_processors;
> -		if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
> -			pr->shared_type = CPUFREQ_SHARED_TYPE_ALL;
> -		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
> -			pr->shared_type = CPUFREQ_SHARED_TYPE_HW;
> -		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
> -			pr->shared_type = CPUFREQ_SHARED_TYPE_ANY;
> -
> -		for_each_possible_cpu(j) {
> -			if (i == j)
> -				continue;
> -
> -			match_cpc_ptr = per_cpu(cpc_desc_ptr, j);
> -			if (!match_cpc_ptr) {
> -				retval = -EFAULT;
> -				goto err_ret;
> -			}
> -
> -			match_pdomain = &(match_cpc_ptr->domain_info);
> -			if (match_pdomain->domain != pdomain->domain)
> -				continue;
> +	for_each_possible_cpu(i) {
> +		if (i == cpu)
> +			continue;
>   
> -			/* Here i and j are in the same domain */
> -			if (match_pdomain->num_processors != count_target) {
> -				retval = -EFAULT;
> -				goto err_ret;
> -			}
> +		match_cpc_ptr = per_cpu(cpc_desc_ptr, i);
> +		if (!match_cpc_ptr)
> +			goto err_fault;
>   
> -			if (pdomain->coord_type != match_pdomain->coord_type) {
> -				retval = -EFAULT;
> -				goto err_ret;
> -			}
> +		match_pdomain = &(match_cpc_ptr->domain_info);
> +		if (match_pdomain->domain != pdomain->domain)
> +			continue;
>   
> -			cpumask_set_cpu(j, covered_cpus);
> -			cpumask_set_cpu(j, pr->shared_cpu_map);
> -		}
> +		/* Here i and cpu are in the same domain */
> +		if (match_pdomain->num_processors != count_target)
> +			goto err_fault;
>   
> -		for_each_cpu(j, pr->shared_cpu_map) {
> -			if (i == j)
> -				continue;
> +		if (pdomain->coord_type != match_pdomain->coord_type)
> +			goto err_fault;
>   
> -			match_pr = all_cpu_data[j];
> -			match_pr->shared_type = pr->shared_type;
> -			cpumask_copy(match_pr->shared_cpu_map,
> -				     pr->shared_cpu_map);
> -		}
> +		cpumask_set_cpu(i, domain->shared_cpu_map);
>   	}
> -	goto out;
>   
> -err_ret:
> -	for_each_possible_cpu(i) {
> -		pr = all_cpu_data[i];
> +	return 0;
>   
> -		/* Assume no coordination on any error parsing domain info */
> -		cpumask_clear(pr->shared_cpu_map);
> -		cpumask_set_cpu(i, pr->shared_cpu_map);
> -		pr->shared_type = CPUFREQ_SHARED_TYPE_ALL;
> -	}
> -out:
> -	free_cpumask_var(covered_cpus);
> -	return retval;
> +err_fault:
> +	/* Assume no coordination on any error parsing domain info */
> +	cpumask_clear(domain->shared_cpu_map);
> +	cpumask_set_cpu(cpu, domain->shared_cpu_map);
> +	domain->shared_type = CPUFREQ_SHARED_TYPE_ALL;
> +
> +	return -EFAULT;
>   }
>   EXPORT_SYMBOL_GPL(acpi_get_psd_map);
>   
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 7cc9bd8568de..ac95b4424a2e 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -30,13 +30,12 @@
>   #define DMI_PROCESSOR_MAX_SPEED		0x14
>   
>   /*
> - * These structs contain information parsed from per CPU
> - * ACPI _CPC structures.
> - * e.g. For each CPU the highest, lowest supported
> - * performance capabilities, desired performance level
> - * requested etc.
> + * This list contains information parsed from per CPU ACPI _CPC and _PSD
> + * structures: this is a list of domain data which in turn contains a list
> + * of cpus with their controls and capabilities, belonging to the domain.
>    */
> -static struct cppc_cpudata **all_cpu_data;
> +static LIST_HEAD(domain_list);
> +
>   static bool boost_supported;
>   
>   struct cppc_workaround_oem_info {
> @@ -148,8 +147,9 @@ static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data,
>   static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
>   				   unsigned int target_freq,
>   				   unsigned int relation)
> +
>   {
> -	struct cppc_cpudata *cpu_data = all_cpu_data[policy->cpu];
> +	struct cppc_cpudata *cpu_data = policy->driver_data;
>   	struct cpufreq_freqs freqs;
>   	u32 desired_perf;
>   	int ret = 0;
> @@ -182,7 +182,7 @@ static int cppc_verify_policy(struct cpufreq_policy_data *policy)
>   
>   static void cppc_cpufreq_stop_cpu(struct cpufreq_policy *policy)
>   {
> -	struct cppc_cpudata *cpu_data = all_cpu_data[policy->cpu];
> +	struct cppc_cpudata *cpu_data = policy->driver_data;
>   	struct cppc_perf_caps *caps = &cpu_data->perf_caps;
>   	unsigned int cpu = policy->cpu;
>   	int ret;
> @@ -238,25 +238,107 @@ static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
>   }
>   #endif
>   
> -static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> +static struct psd_data *cppc_cpufreq_get_domain(unsigned int cpu)
>   {
> -	struct cppc_cpudata *cpu_data = all_cpu_data[policy->cpu];
> -	struct cppc_perf_caps *caps = &cpu_data->perf_caps;
> -	unsigned int cpu = policy->cpu;
> -	int ret = 0;
> +	struct psd_data *domain;
> +	int ret;
>   
> -	cpu_data->cpu = cpu;
> -	ret = cppc_get_perf_caps(cpu, caps);
> +	list_for_each_entry(domain, &domain_list, node) {
> +		if (cpumask_test_cpu(cpu, domain->shared_cpu_map))
> +			return domain;
> +	}
>   
> +	domain = kzalloc(sizeof(struct psd_data), GFP_KERNEL);
> +	if (!domain)
> +		return NULL;
> +	if (!zalloc_cpumask_var(&domain->shared_cpu_map, GFP_KERNEL))
> +		goto free_domain;
> +	INIT_LIST_HEAD(&domain->cpu_list);
> +
> +	ret = acpi_get_psd_map(cpu, domain);
>   	if (ret) {
> -		pr_debug("Err reading CPU%d perf capabilities. ret:%d\n",
> -			 cpu, ret);
> -		return ret;
> +		pr_err("Error parsing PSD data for CPU%d.\n", cpu);
> +		goto free_mask;
> +	}
> +
> +	list_add(&domain->node, &domain_list);
> +
> +	return domain;
> +
> +free_mask:
> +	free_cpumask_var(domain->shared_cpu_map);
> +free_domain:
> +	kfree(domain);
> +
> +	return NULL;
> +}
> +
> +static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
> +{
> +	struct cppc_cpudata *cpu_data;
> +	struct psd_data *domain;
> +	int ret;
> +
> +	domain = cppc_cpufreq_get_domain(cpu);
> +	if (!domain) {
> +		pr_err("Error acquiring domain for CPU.\n");
> +		return NULL;
>   	}
>   
> +	list_for_each_entry(cpu_data, &domain->cpu_list, node) {
> +		if (cpu_data->cpu == cpu)
> +			return cpu_data;
> +	}
> +
> +	if ((domain->shared_type == CPUFREQ_SHARED_TYPE_ANY) &&
> +	    !list_empty(&domain->cpu_list))
> +		return list_first_entry(&domain->cpu_list,
> +					struct cppc_cpudata,
> +					node);
> +
> +	cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);
> +	if (!cpu_data)
> +		return NULL;
> +
> +	cpu_data->cpu = cpu;
> +	cpu_data->domain = domain;
> +
> +	ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps);
> +	if (ret) {
> +		pr_err("Err reading CPU%d perf capabilities. ret:%d\n",
> +			cpu, ret);
> +		goto free;
> +	}
>   	/* Convert the lowest and nominal freq from MHz to KHz */
> -	caps->lowest_freq *= 1000;
> -	caps->nominal_freq *= 1000;
> +	cpu_data->perf_caps.lowest_freq *= 1000;
> +	cpu_data->perf_caps.nominal_freq *= 1000;
> +
> +	list_add(&cpu_data->node, &domain->cpu_list);
> +
> +	return cpu_data;
> +free:
> +	kfree(cpu_data);
> +
> +	return NULL;
> +}
> +
> +static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
> +{
> +	struct cppc_cpudata *cpu_data = NULL;
> +	struct psd_data *domain = NULL;
> +	unsigned int cpu = policy->cpu;
> +	struct cppc_perf_caps *caps;
> +	int ret = 0;
> +
> +	cpu_data = cppc_cpufreq_get_cpu_data(cpu);
> +	if (!cpu_data) {
> +		pr_err("Error in acquiring _CPC/_PSD data for CPU.\n");
> +		return -ENODEV;
> +	}
> +
> +	domain = cpu_data->domain;
> +	caps = &cpu_data->perf_caps;
> +	policy->driver_data = cpu_data;
>   
>   	/*
>   	 * Set min to lowest nonlinear perf to avoid any efficiency penalty (see
> @@ -278,20 +360,10 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
>   							    caps->nominal_perf);
>   
>   	policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu);
> -	policy->shared_type = cpu_data->shared_type;
> +	policy->shared_type = domain->shared_type;
>   
>   	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
> -		int i;
> -
> -		cpumask_copy(policy->cpus, cpu_data->shared_cpu_map);
> -
> -		for_each_cpu(i, policy->cpus) {
> -			if (unlikely(i == cpu))
> -				continue;
> -
> -			memcpy(&all_cpu_data[i]->perf_caps, caps,
> -			       sizeof(cpu_data->perf_caps));
> -		}
> +		cpumask_copy(policy->cpus, domain->shared_cpu_map);
>   	} else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
>   		/* Support only SW_ANY for now. */
>   		pr_debug("Unsupported CPU co-ord type\n");
> @@ -354,9 +426,12 @@ static int cppc_get_rate_from_fbctrs(struct cppc_cpudata *cpu_data,
>   static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
>   {
>   	struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0};
> -	struct cppc_cpudata *cpu_data = all_cpu_data[cpu];
> +	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> +	struct cppc_cpudata *cpu_data = policy->driver_data;
>   	int ret;
>   
> +	cpufreq_cpu_put(policy);
> +
>   	ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0);
>   	if (ret)
>   		return ret;
> @@ -372,7 +447,7 @@ static unsigned int cppc_cpufreq_get_rate(unsigned int cpu)
>   
>   static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
>   {
> -	struct cppc_cpudata *cpu_data = all_cpu_data[policy->cpu];
> +	struct cppc_cpudata *cpu_data = policy->driver_data;
>   	struct cppc_perf_caps *caps = &cpu_data->perf_caps;
>   	int ret;
>   
> @@ -415,10 +490,13 @@ static struct cpufreq_driver cppc_cpufreq_driver = {
>    */
>   static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu)
>   {
> -	struct cppc_cpudata *cpu_data = all_cpu_data[cpu];
> +	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> +	struct cppc_cpudata *cpu_data = policy->driver_data;
>   	u64 desired_perf;
>   	int ret;
>   
> +	cpufreq_cpu_put(policy);
> +
>   	ret = cppc_get_desired_perf(cpu, &desired_perf);
>   	if (ret < 0)
>   		return -EIO;
> @@ -451,68 +529,41 @@ static void cppc_check_hisi_workaround(void)
>   
>   static int __init cppc_cpufreq_init(void)
>   {
> -	struct cppc_cpudata *cpu_data;
> -	int i, ret = 0;
> -
>   	if (acpi_disabled)
>   		return -ENODEV;
>   
> -	all_cpu_data = kcalloc(num_possible_cpus(), sizeof(void *),
> -			       GFP_KERNEL);
> -	if (!all_cpu_data)
> -		return -ENOMEM;
> -
> -	for_each_possible_cpu(i) {
> -		all_cpu_data[i] = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL);
> -		if (!all_cpu_data[i])
> -			goto out;
> -
> -		cpu_data = all_cpu_data[i];
> -		if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL))
> -			goto out;
> -	}
> -
> -	ret = acpi_get_psd_map(all_cpu_data);
> -	if (ret) {
> -		pr_debug("Error parsing PSD data. Aborting cpufreq registration.\n");
> -		goto out;
> -	}
> -
>   	cppc_check_hisi_workaround();
>   
> -	ret = cpufreq_register_driver(&cppc_cpufreq_driver);
> -	if (ret)
> -		goto out;
> +	return cpufreq_register_driver(&cppc_cpufreq_driver);
> +}
>   
> -	return ret;
> +static inline void free_cpu_data(struct psd_data *domain)
> +{
> +	struct cppc_cpudata *iter, *tmp;
>   
> -out:
> -	for_each_possible_cpu(i) {
> -		cpu_data = all_cpu_data[i];
> -		if (!cpu_data)
> -			break;
> -		free_cpumask_var(cpu_data->shared_cpu_map);
> -		kfree(cpu_data);
> +	list_for_each_entry_safe(iter, tmp, &domain->cpu_list, node) {
> +		list_del(&iter->node);
> +		kfree(iter);
>   	}
> -
> -	kfree(all_cpu_data);
> -	return -ENODEV;
>   }
>   
> +static inline void free_domain_data(void)
> +{
> +	struct psd_data *iter, *tmp;
> +
> +	list_for_each_entry_safe(iter, tmp, &domain_list, node) {
> +		list_del(&iter->node);
> +		if (!list_empty(&iter->cpu_list))
> +			free_cpu_data(iter);
> +		free_cpumask_var(iter->shared_cpu_map);
> +		kfree(iter);
> +	}
> +}
>   static void __exit cppc_cpufreq_exit(void)
>   {
> -	struct cppc_cpudata *cpu_data;
> -	int i;
> -
>   	cpufreq_unregister_driver(&cppc_cpufreq_driver);
>   
> -	for_each_possible_cpu(i) {
> -		cpu_data = all_cpu_data[i];
> -		free_cpumask_var(cpu_data->shared_cpu_map);
> -		kfree(cpu_data);
> -	}
> -
> -	kfree(all_cpu_data);
> +	free_domain_data();
>   }
>   
>   module_exit(cppc_cpufreq_exit);
> diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
> index a6a9373ab863..c0081fb6032e 100644
> --- a/include/acpi/cppc_acpi.h
> +++ b/include/acpi/cppc_acpi.h
> @@ -122,22 +122,30 @@ struct cppc_perf_fb_ctrs {
>   	u64 wraparound_time;
>   };
>   
> +/* Container of performance state domain data */
> +struct psd_data {
> +	struct list_head node;
> +	unsigned int shared_type;
> +	struct list_head cpu_list;
> +	cpumask_var_t shared_cpu_map;
> +};
> +
>   /* Per CPU container for runtime CPPC management. */
>   struct cppc_cpudata {
>   	int cpu;
> +	struct list_head node;
> +	struct psd_data *domain;
>   	struct cppc_perf_caps perf_caps;
>   	struct cppc_perf_ctrls perf_ctrls;
>   	struct cppc_perf_fb_ctrs perf_fb_ctrs;
>   	struct cpufreq_policy *cur_policy;
> -	unsigned int shared_type;
> -	cpumask_var_t shared_cpu_map;
>   };
>   
>   extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf);
>   extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs);
>   extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls);
>   extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps);
> -extern int acpi_get_psd_map(struct cppc_cpudata **);
> +extern int acpi_get_psd_map(unsigned int cpu, struct psd_data *domain);
>   extern unsigned int cppc_get_transition_latency(int cpu);
>   extern bool cpc_ffh_supported(void);
>   extern int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val);
>