cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t

Impact: Reduce memory usage, use new API.

This is part of an effort to reduce structure sizes for machines
configured with large NR_CPUS.  cpumask_t gets replaced by
cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or
struct cpumask * (large NR_CPUS).

(Changes to powernow-k* by <travis>.)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c

@@ -517,6 +517,17 @@ acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 	}
 }
 
+static void free_acpi_perf_data(void)
+{
+	unsigned int i;
+
+	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
+	for_each_possible_cpu(i)
+		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
+				 ->shared_cpu_map);
+	free_percpu(acpi_perf_data);
+}
+
 /*
  * acpi_cpufreq_early_init - initialize ACPI P-States library
  *
@@ -527,6 +538,7 @@ acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
  */
 static int __init acpi_cpufreq_early_init(void)
 {
+	unsigned int i;
 	dprintk("acpi_cpufreq_early_init\n");
 
 	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
@@ -534,6 +546,15 @@ static int __init acpi_cpufreq_early_init(void)
 		dprintk("Memory allocation error for acpi_perf_data.\n");
 		return -ENOMEM;
 	}
+	for_each_possible_cpu(i) {
+		if (!alloc_cpumask_var(&per_cpu_ptr(acpi_perf_data, i)
+				       ->shared_cpu_map, GFP_KERNEL)) {
+
+			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
+			free_acpi_perf_data();
+			return -ENOMEM;
+		}
+	}
 
 	/* Do initialization in ACPI core */
 	acpi_processor_preregister_performance(acpi_perf_data);
@@ -604,9 +625,9 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 	 */
 	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
-		policy->cpus = perf->shared_cpu_map;
+		cpumask_copy(&policy->cpus, perf->shared_cpu_map);
 	}
-	policy->related_cpus = perf->shared_cpu_map;
+	cpumask_copy(&policy->related_cpus, perf->shared_cpu_map);
 
 #ifdef CONFIG_SMP
 	dmi_check_system(sw_any_bug_dmi_table);
@@ -795,7 +816,7 @@ static int __init acpi_cpufreq_init(void)
 
 	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 	if (ret)
-		free_percpu(acpi_perf_data);
+		free_acpi_perf_data();
 
 	return ret;
 }

arch/x86/kernel/cpu/cpufreq/powernow-k7.c

@@ -310,6 +310,12 @@ static int powernow_acpi_init(void)
 		goto err0;
 	}
 
+	if (!alloc_cpumask_var(&acpi_processor_perf->shared_cpu_map,
+								GFP_KERNEL)) {
+		retval = -ENOMEM;
+		goto err05;
+	}
+
 	if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
 		retval = -EIO;
 		goto err1;
@@ -412,6 +418,8 @@ static int powernow_acpi_init(void)
 err2:
 	acpi_processor_unregister_performance(acpi_processor_perf, 0);
 err1:
+	free_cpumask_var(acpi_processor_perf->shared_cpu_map);
+err05:
 	kfree(acpi_processor_perf);
 err0:
 	printk(KERN_WARNING PFX "ACPI perflib can not be used in this platform\n");
@@ -652,6 +660,7 @@ static int powernow_cpu_exit (struct cpufreq_policy *policy) {
 #ifdef CONFIG_X86_POWERNOW_K7_ACPI
 	if (acpi_processor_perf) {
 		acpi_processor_unregister_performance(acpi_processor_perf, 0);
+		free_cpumask_var(acpi_processor_perf->shared_cpu_map);
 		kfree(acpi_processor_perf);
 	}
 #endif

arch/x86/kernel/cpu/cpufreq/powernow-k8.c

@@ -766,7 +766,7 @@ static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned
 static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 {
 	struct cpufreq_frequency_table *powernow_table;
-	int ret_val;
+	int ret_val = -ENODEV;
 
 	if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
 		dprintk("register performance failed: bad ACPI data\n");
@@ -815,6 +815,13 @@ static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
 	/* notify BIOS that we exist */
 	acpi_processor_notify_smm(THIS_MODULE);
 
+	if (!alloc_cpumask_var(&data->acpi_data.shared_cpu_map, GFP_KERNEL)) {
+		printk(KERN_ERR PFX
+				"unable to alloc powernow_k8_data cpumask\n");
+		ret_val = -ENOMEM;
+		goto err_out_mem;
+	}
+
 	return 0;
 
 err_out_mem:
@@ -826,7 +833,7 @@ err_out:
 	/* data->acpi_data.state_count informs us at ->exit() whether ACPI was used */
 	data->acpi_data.state_count = 0;
 
-	return -ENODEV;
+	return ret_val;
 }
 
 static int fill_powernow_table_pstate(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table)
@@ -929,6 +936,7 @@ static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
 {
 	if (data->acpi_data.state_count)
 		acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
+	free_cpumask_var(data->acpi_data.shared_cpu_map);
 }
 
 #else
@@ -1134,7 +1142,8 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
 	data->cpu = pol->cpu;
 	data->currpstate = HW_PSTATE_INVALID;
 
-	if (powernow_k8_cpu_init_acpi(data)) {
+	rc = powernow_k8_cpu_init_acpi(data);
+	if (rc) {
 		/*
 		 * Use the PSB BIOS structure. This is only availabe on
 		 * an UP version, and is deprecated by AMD.
@@ -1152,20 +1161,17 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
 			       "ACPI maintainers and complain to your BIOS "
 			       "vendor.\n");
 #endif
-			kfree(data);
-			return -ENODEV;
+			goto err_out;
 		}
 		if (pol->cpu != 0) {
 			printk(KERN_ERR FW_BUG PFX "No ACPI _PSS objects for "
 			       "CPU other than CPU0. Complain to your BIOS "
 			       "vendor.\n");
-			kfree(data);
-			return -ENODEV;
+			goto err_out;
 		}
 		rc = find_psb_table(data);
 		if (rc) {
-			kfree(data);
-			return -ENODEV;
+			goto err_out;
 		}
 	}
 

drivers/acpi/processor_core.c

@@ -826,6 +826,11 @@ static int acpi_processor_add(struct acpi_device *device)
 	if (!pr)
 		return -ENOMEM;
 
+	if (!alloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
+		kfree(pr);
+		return -ENOMEM;
+	}
+
 	pr->handle = device->handle;
 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
@@ -845,10 +850,8 @@ static int acpi_processor_remove(struct acpi_device *device, int type)
 
 	pr = acpi_driver_data(device);
 
-	if (pr->id >= nr_cpu_ids) {
-		kfree(pr);
-		return 0;
-	}
+	if (pr->id >= nr_cpu_ids)
+		goto free;
 
 	if (type == ACPI_BUS_REMOVAL_EJECT) {
 		if (acpi_processor_handle_eject(pr))
@@ -873,6 +876,9 @@ static int acpi_processor_remove(struct acpi_device *device, int type)
 
 	per_cpu(processors, pr->id) = NULL;
 	per_cpu(processor_device_array, pr->id) = NULL;
+
+free:
+	free_cpumask_var(pr->throttling.shared_cpu_map);
 	kfree(pr);
 
 	return 0;

drivers/acpi/processor_perflib.c

@@ -588,12 +588,15 @@ int acpi_processor_preregister_performance(
 	int count, count_target;
 	int retval = 0;
 	unsigned int i, j;
-	cpumask_t covered_cpus;
+	cpumask_var_t covered_cpus;
 	struct acpi_processor *pr;
 	struct acpi_psd_package *pdomain;
 	struct acpi_processor *match_pr;
 	struct acpi_psd_package *match_pdomain;
 
+	if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
+		return -ENOMEM;
+
 	mutex_lock(&performance_mutex);
 
 	retval = 0;
@@ -617,7 +620,7 @@ int acpi_processor_preregister_performance(
 		}
 
 		pr->performance = percpu_ptr(performance, i);
-		cpu_set(i, pr->performance->shared_cpu_map);
+		cpumask_set_cpu(i, pr->performance->shared_cpu_map);
 		if (acpi_processor_get_psd(pr)) {
 			retval = -EINVAL;
 			continue;
@@ -650,18 +653,18 @@ int acpi_processor_preregister_performance(
 		}
 	}
 
-	cpus_clear(covered_cpus);
+	cpumask_clear(covered_cpus);
 	for_each_possible_cpu(i) {
 		pr = per_cpu(processors, i);
 		if (!pr)
 			continue;
 
-		if (cpu_isset(i, covered_cpus))
+		if (cpumask_test_cpu(i, covered_cpus))
 			continue;
 
 		pdomain = &(pr->performance->domain_info);
-		cpu_set(i, pr->performance->shared_cpu_map);
-		cpu_set(i, covered_cpus);
+		cpumask_set_cpu(i, pr->performance->shared_cpu_map);
+		cpumask_set_cpu(i, covered_cpus);
 		if (pdomain->num_processors <= 1)
 			continue;
 
@@ -699,8 +702,8 @@ int acpi_processor_preregister_performance(
 				goto err_ret;
 			}
 
-			cpu_set(j, covered_cpus);
-			cpu_set(j, pr->performance->shared_cpu_map);
+			cpumask_set_cpu(j, covered_cpus);
+			cpumask_set_cpu(j, pr->performance->shared_cpu_map);
 			count++;
 		}
 
@@ -718,8 +721,8 @@ int acpi_processor_preregister_performance(
 
 			match_pr->performance->shared_type = 
 					pr->performance->shared_type;
-			match_pr->performance->shared_cpu_map =
-				pr->performance->shared_cpu_map;
+			cpumask_copy(match_pr->performance->shared_cpu_map,
+				     pr->performance->shared_cpu_map);
 		}
 	}
 
@@ -731,14 +734,15 @@ err_ret:
 
 		/* Assume no coordination on any error parsing domain info */
 		if (retval) {
-			cpus_clear(pr->performance->shared_cpu_map);
-			cpu_set(i, pr->performance->shared_cpu_map);
+			cpumask_clear(pr->performance->shared_cpu_map);
+			cpumask_set_cpu(i, pr->performance->shared_cpu_map);
 			pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 		}
 		pr->performance = NULL; /* Will be set for real in register */
 	}
 
 	mutex_unlock(&performance_mutex);
+	free_cpumask_var(covered_cpus);
 	return retval;
 }
 EXPORT_SYMBOL(acpi_processor_preregister_performance);

drivers/acpi/processor_throttling.c

@@ -61,11 +61,14 @@ static int acpi_processor_update_tsd_coord(void)
 	int count, count_target;
 	int retval = 0;
 	unsigned int i, j;
-	cpumask_t covered_cpus;
+	cpumask_var_t covered_cpus;
 	struct acpi_processor *pr, *match_pr;
 	struct acpi_tsd_package *pdomain, *match_pdomain;
 	struct acpi_processor_throttling *pthrottling, *match_pthrottling;
 
+	if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
+		return -ENOMEM;
+
 	/*
 	 * Now that we have _TSD data from all CPUs, lets setup T-state
 	 * coordination between all CPUs.
@@ -91,19 +94,19 @@ static int acpi_processor_update_tsd_coord(void)
 	if (retval)
 		goto err_ret;
 
-	cpus_clear(covered_cpus);
+	cpumask_clear(covered_cpus);
 	for_each_possible_cpu(i) {
 		pr = per_cpu(processors, i);
 		if (!pr)
 			continue;
 
-		if (cpu_isset(i, covered_cpus))
+		if (cpumask_test_cpu(i, covered_cpus))
 			continue;
 		pthrottling = &pr->throttling;
 
 		pdomain = &(pthrottling->domain_info);
-		cpu_set(i, pthrottling->shared_cpu_map);
-		cpu_set(i, covered_cpus);
+		cpumask_set_cpu(i, pthrottling->shared_cpu_map);
+		cpumask_set_cpu(i, covered_cpus);
 		/*
 		 * If the number of processor in the TSD domain is 1, it is
 		 * unnecessary to parse the coordination for this CPU.
@@ -144,8 +147,8 @@ static int acpi_processor_update_tsd_coord(void)
 				goto err_ret;
 			}
 
-			cpu_set(j, covered_cpus);
-			cpu_set(j, pthrottling->shared_cpu_map);
+			cpumask_set_cpu(j, covered_cpus);
+			cpumask_set_cpu(j, pthrottling->shared_cpu_map);
 			count++;
 		}
 		for_each_possible_cpu(j) {
@@ -165,12 +168,14 @@ static int acpi_processor_update_tsd_coord(void)
 			 * If some CPUS have the same domain, they
 			 * will have the same shared_cpu_map.
 			 */
-			match_pthrottling->shared_cpu_map =
-				pthrottling->shared_cpu_map;
+			cpumask_copy(match_pthrottling->shared_cpu_map,
+				     pthrottling->shared_cpu_map);
 		}
 	}
 
 err_ret:
+	free_cpumask_var(covered_cpus);
+
 	for_each_possible_cpu(i) {
 		pr = per_cpu(processors, i);
 		if (!pr)
@@ -182,8 +187,8 @@ err_ret:
 		 */
 		if (retval) {
 			pthrottling = &(pr->throttling);
-			cpus_clear(pthrottling->shared_cpu_map);
-			cpu_set(i, pthrottling->shared_cpu_map);
+			cpumask_clear(pthrottling->shared_cpu_map);
+			cpumask_set_cpu(i, pthrottling->shared_cpu_map);
 			pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
 		}
 	}
@@ -567,7 +572,7 @@ static int acpi_processor_get_tsd(struct acpi_processor *pr)
 	pthrottling = &pr->throttling;
 	pthrottling->tsd_valid_flag = 1;
 	pthrottling->shared_type = pdomain->coord_type;
-	cpu_set(pr->id, pthrottling->shared_cpu_map);
+	cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
 	/*
 	 * If the coordination type is not defined in ACPI spec,
 	 * the tsd_valid_flag will be clear and coordination type
@@ -826,7 +831,7 @@ static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
 
 static int acpi_processor_get_throttling(struct acpi_processor *pr)
 {
-	cpumask_t saved_mask;
+	cpumask_var_t saved_mask;
 	int ret;
 
 	if (!pr)
@@ -834,14 +839,20 @@ static int acpi_processor_get_throttling(struct acpi_processor *pr)
 
 	if (!pr->flags.throttling)
 		return -ENODEV;
+
+	if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
+		return -ENOMEM;
+
 	/*
 	 * Migrate task to the cpu pointed by pr.
 	 */
-	saved_mask = current->cpus_allowed;
-	set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
+	cpumask_copy(saved_mask, &current->cpus_allowed);
+	/* FIXME: use work_on_cpu() */
+	set_cpus_allowed_ptr(current, cpumask_of(pr->id));
 	ret = pr->throttling.acpi_processor_get_throttling(pr);
 	/* restore the previous state */
-	set_cpus_allowed_ptr(current, &saved_mask);
+	set_cpus_allowed_ptr(current, saved_mask);
+	free_cpumask_var(saved_mask);
 
 	return ret;
 }
@@ -986,13 +997,13 @@ static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
 
 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 {
-	cpumask_t saved_mask;
+	cpumask_var_t saved_mask;
 	int ret = 0;
 	unsigned int i;
 	struct acpi_processor *match_pr;
 	struct acpi_processor_throttling *p_throttling;
 	struct throttling_tstate t_state;
-	cpumask_t online_throttling_cpus;
+	cpumask_var_t online_throttling_cpus;
 
 	if (!pr)
 		return -EINVAL;
@@ -1003,17 +1014,25 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 	if ((state < 0) || (state > (pr->throttling.state_count - 1)))
 		return -EINVAL;
 
-	saved_mask = current->cpus_allowed;
+	if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
+		free_cpumask_var(saved_mask);
+		return -ENOMEM;
+	}
+
+	cpumask_copy(saved_mask, &current->cpus_allowed);
 	t_state.target_state = state;
 	p_throttling = &(pr->throttling);
-	cpus_and(online_throttling_cpus, cpu_online_map,
-			p_throttling->shared_cpu_map);
+	cpumask_and(online_throttling_cpus, cpu_online_mask,
+		    p_throttling->shared_cpu_map);
 	/*
 	 * The throttling notifier will be called for every
 	 * affected cpu in order to get one proper T-state.
 	 * The notifier event is THROTTLING_PRECHANGE.
 	 */
-	for_each_cpu_mask_nr(i, online_throttling_cpus) {
+	for_each_cpu(i, online_throttling_cpus) {
 		t_state.cpu = i;
 		acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
 							&t_state);
@@ -1025,7 +1044,8 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 	 * it can be called only for the cpu pointed by pr.
 	 */
 	if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
-		set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
+		/* FIXME: use work_on_cpu() */
+		set_cpus_allowed_ptr(current, cpumask_of(pr->id));
 		ret = p_throttling->acpi_processor_set_throttling(pr,
 						t_state.target_state);
 	} else {
@@ -1034,7 +1054,7 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 		 * it is necessary to set T-state for every affected
 		 * cpus.
 		 */
-		for_each_cpu_mask_nr(i, online_throttling_cpus) {
+		for_each_cpu(i, online_throttling_cpus) {
 			match_pr = per_cpu(processors, i);
 			/*
 			 * If the pointer is invalid, we will report the
@@ -1056,7 +1076,8 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 				continue;
 			}
 			t_state.cpu = i;
-			set_cpus_allowed_ptr(current, &cpumask_of_cpu(i));
+			/* FIXME: use work_on_cpu() */
+			set_cpus_allowed_ptr(current, cpumask_of(i));
 			ret = match_pr->throttling.
 				acpi_processor_set_throttling(
 				match_pr, t_state.target_state);
@@ -1068,13 +1089,16 @@ int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
 	 * affected cpu to update the T-states.
 	 * The notifier event is THROTTLING_POSTCHANGE
 	 */
-	for_each_cpu_mask_nr(i, online_throttling_cpus) {
+	for_each_cpu(i, online_throttling_cpus) {
 		t_state.cpu = i;
 		acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
 							&t_state);
 	}
 	/* restore the previous state */
-	set_cpus_allowed_ptr(current, &saved_mask);
+	/* FIXME: use work_on_cpu() */
+	set_cpus_allowed_ptr(current, saved_mask);
+	free_cpumask_var(online_throttling_cpus);
+	free_cpumask_var(saved_mask);
 	return ret;
 }
 
@@ -1120,7 +1144,7 @@ int acpi_processor_get_throttling_info(struct acpi_processor *pr)
 	if (acpi_processor_get_tsd(pr)) {
 		pthrottling = &pr->throttling;
 		pthrottling->tsd_valid_flag = 0;
-		cpu_set(pr->id, pthrottling->shared_cpu_map);
+		cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
 		pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
 	}
 

include/acpi/processor.h

@@ -127,7 +127,7 @@ struct acpi_processor_performance {
 	unsigned int state_count;
 	struct acpi_processor_px *states;
 	struct acpi_psd_package domain_info;
-	cpumask_t shared_cpu_map;
+	cpumask_var_t shared_cpu_map;
 	unsigned int shared_type;
 };
 
@@ -172,7 +172,7 @@ struct acpi_processor_throttling {
 	unsigned int state_count;
 	struct acpi_processor_tx_tss *states_tss;
 	struct acpi_tsd_package domain_info;
-	cpumask_t shared_cpu_map;
+	cpumask_var_t shared_cpu_map;
 	int (*acpi_processor_get_throttling) (struct acpi_processor * pr);
 	int (*acpi_processor_set_throttling) (struct acpi_processor * pr,
 					      int state);