OSCL-LXR linux-6.0.1/​drivers/​base/​arch_topology.c	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Arch specific cpu topology information
  *
  * Copyright (C) 2016, ARM Ltd.
  * Written by: Juri Lelli, ARM Ltd.
  */
 
 #include <linux/acpi.h>
 #include <linux/cacheinfo.h>
 #include <linux/cpu.h>
 #include <linux/cpufreq.h>
 #include <linux/device.h>
 #include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/sched/topology.h>
 #include <linux/cpuset.h>
 #include <linux/cpumask.h>
 #include <linux/init.h>
 #include <linux/rcupdate.h>
 #include <linux/sched.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/thermal_pressure.h>
 
 static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data);
 static struct cpumask scale_freq_counters_mask;
 static bool scale_freq_invariant;
 static DEFINE_PER_CPU(u32, freq_factor) = 1;
 
 static bool supports_scale_freq_counters(const struct cpumask *cpus)
 {
     return cpumask_subset(cpus, &scale_freq_counters_mask);
 }
 
 bool topology_scale_freq_invariant(void)
 {
     return cpufreq_supports_freq_invariance() ||
            supports_scale_freq_counters(cpu_online_mask);
 }
 
 static void update_scale_freq_invariant(bool status)
 {
     if (scale_freq_invariant == status)
         return;
 
     /*
      * Task scheduler behavior depends on frequency invariance support,
      * either cpufreq or counter driven. If the support status changes as
      * a result of counter initialisation and use, retrigger the build of
      * scheduling domains to ensure the information is propagated properly.
      */
     if (topology_scale_freq_invariant() == status) {
         scale_freq_invariant = status;
         rebuild_sched_domains_energy();
     }
 }
 
 void topology_set_scale_freq_source(struct scale_freq_data *data,
                     const struct cpumask *cpus)
 {
     struct scale_freq_data *sfd;
     int cpu;
 
     /*
      * Avoid calling rebuild_sched_domains() unnecessarily if FIE is
      * supported by cpufreq.
      */
     if (cpumask_empty(&scale_freq_counters_mask))
         scale_freq_invariant = topology_scale_freq_invariant();
 
     rcu_read_lock();
 
     for_each_cpu(cpu, cpus) {
         sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
 
         /* Use ARCH provided counters whenever possible */
         if (!sfd || sfd->source != SCALE_FREQ_SOURCE_ARCH) {
             rcu_assign_pointer(per_cpu(sft_data, cpu), data);
             cpumask_set_cpu(cpu, &scale_freq_counters_mask);
         }
     }
 
     rcu_read_unlock();
 
     update_scale_freq_invariant(true);
 }
 EXPORT_SYMBOL_GPL(topology_set_scale_freq_source);
 
 void topology_clear_scale_freq_source(enum scale_freq_source source,
                       const struct cpumask *cpus)
 {
     struct scale_freq_data *sfd;
     int cpu;
 
     rcu_read_lock();
 
     for_each_cpu(cpu, cpus) {
         sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
 
         if (sfd && sfd->source == source) {
             rcu_assign_pointer(per_cpu(sft_data, cpu), NULL);
             cpumask_clear_cpu(cpu, &scale_freq_counters_mask);
         }
     }
 
     rcu_read_unlock();
 
     /*
      * Make sure all references to previous sft_data are dropped to avoid
      * use-after-free races.
      */
     synchronize_rcu();
 
     update_scale_freq_invariant(false);
 }
 EXPORT_SYMBOL_GPL(topology_clear_scale_freq_source);
 
 void topology_scale_freq_tick(void)
 {
     struct scale_freq_data *sfd = rcu_dereference_sched(*this_cpu_ptr(&sft_data));
 
     if (sfd)
         sfd->set_freq_scale();
 }
 
 DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE;
 EXPORT_PER_CPU_SYMBOL_GPL(arch_freq_scale);
 
 void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq,
                  unsigned long max_freq)
 {
     unsigned long scale;
     int i;
 
     if (WARN_ON_ONCE(!cur_freq || !max_freq))
         return;
 
     /*
      * If the use of counters for FIE is enabled, just return as we don't
      * want to update the scale factor with information from CPUFREQ.
      * Instead the scale factor will be updated from arch_scale_freq_tick.
      */
     if (supports_scale_freq_counters(cpus))
         return;
 
     scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq;
 
     for_each_cpu(i, cpus)
         per_cpu(arch_freq_scale, i) = scale;
 }
 
 DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
 EXPORT_PER_CPU_SYMBOL_GPL(cpu_scale);
 
 void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
 {
     per_cpu(cpu_scale, cpu) = capacity;
 }
 
 DEFINE_PER_CPU(unsigned long, thermal_pressure);
 
 /**
  * topology_update_thermal_pressure() - Update thermal pressure for CPUs
  * @cpus        : The related CPUs for which capacity has been reduced
  * @capped_freq : The maximum allowed frequency that CPUs can run at
  *
  * Update the value of thermal pressure for all @cpus in the mask. The
  * cpumask should include all (online+offline) affected CPUs, to avoid
  * operating on stale data when hot-plug is used for some CPUs. The
  * @capped_freq reflects the currently allowed max CPUs frequency due to
  * thermal capping. It might be also a boost frequency value, which is bigger
  * than the internal 'freq_factor' max frequency. In such case the pressure
  * value should simply be removed, since this is an indication that there is
  * no thermal throttling. The @capped_freq must be provided in kHz.
  */
 void topology_update_thermal_pressure(const struct cpumask *cpus,
                       unsigned long capped_freq)
 {
     unsigned long max_capacity, capacity, th_pressure;
     u32 max_freq;
     int cpu;
 
     cpu = cpumask_first(cpus);
     max_capacity = arch_scale_cpu_capacity(cpu);
     max_freq = per_cpu(freq_factor, cpu);
 
     /* Convert to MHz scale which is used in 'freq_factor' */
     capped_freq /= 1000;
 
     /*
      * Handle properly the boost frequencies, which should simply clean
      * the thermal pressure value.
      */
     if (max_freq <= capped_freq)
         capacity = max_capacity;
     else
         capacity = mult_frac(max_capacity, capped_freq, max_freq);
 
     th_pressure = max_capacity - capacity;
 
     trace_thermal_pressure_update(cpu, th_pressure);
 
     for_each_cpu(cpu, cpus)
         WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
 }
 EXPORT_SYMBOL_GPL(topology_update_thermal_pressure);
 
 static ssize_t cpu_capacity_show(struct device *dev,
                  struct device_attribute *attr,
                  char *buf)
 {
     struct cpu *cpu = container_of(dev, struct cpu, dev);
 
     return sysfs_emit(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
 }
 
 static void update_topology_flags_workfn(struct work_struct *work);
 static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);
 
 static DEVICE_ATTR_RO(cpu_capacity);
 
 static int register_cpu_capacity_sysctl(void)
 {
     int i;
     struct device *cpu;
 
     for_each_possible_cpu(i) {
         cpu = get_cpu_device(i);
         if (!cpu) {
             pr_err("%s: too early to get CPU%d device!\n",
                    __func__, i);
             continue;
         }
         device_create_file(cpu, &dev_attr_cpu_capacity);
     }
 
     return 0;
 }
 subsys_initcall(register_cpu_capacity_sysctl);
 
 static int update_topology;
 
 int topology_update_cpu_topology(void)
 {
     return update_topology;
 }
 
 /*
  * Updating the sched_domains can't be done directly from cpufreq callbacks
  * due to locking, so queue the work for later.
  */
 static void update_topology_flags_workfn(struct work_struct *work)
 {
     update_topology = 1;
     rebuild_sched_domains();
     pr_debug("sched_domain hierarchy rebuilt, flags updated\n");
     update_topology = 0;
 }
 
 static u32 *raw_capacity;
 
 static int free_raw_capacity(void)
 {
     kfree(raw_capacity);
     raw_capacity = NULL;
 
     return 0;
 }
 
 void topology_normalize_cpu_scale(void)
 {
     u64 capacity;
     u64 capacity_scale;
     int cpu;
 
     if (!raw_capacity)
         return;
 
     capacity_scale = 1;
     for_each_possible_cpu(cpu) {
         capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
         capacity_scale = max(capacity, capacity_scale);
     }
 
     pr_debug("cpu_capacity: capacity_scale=%llu\n", capacity_scale);
     for_each_possible_cpu(cpu) {
         capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
         capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
             capacity_scale);
         topology_set_cpu_scale(cpu, capacity);
         pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
             cpu, topology_get_cpu_scale(cpu));
     }
 }
 
 bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
 {
     struct clk *cpu_clk;
     static bool cap_parsing_failed;
     int ret;
     u32 cpu_capacity;
 
     if (cap_parsing_failed)
         return false;
 
     ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
                    &cpu_capacity);
     if (!ret) {
         if (!raw_capacity) {
             raw_capacity = kcalloc(num_possible_cpus(),
                            sizeof(*raw_capacity),
                            GFP_KERNEL);
             if (!raw_capacity) {
                 cap_parsing_failed = true;
                 return false;
             }
         }
         raw_capacity[cpu] = cpu_capacity;
         pr_debug("cpu_capacity: %pOF cpu_capacity=%u (raw)\n",
             cpu_node, raw_capacity[cpu]);
 
         /*
          * Update freq_factor for calculating early boot cpu capacities.
          * For non-clk CPU DVFS mechanism, there's no way to get the
          * frequency value now, assuming they are running at the same
          * frequency (by keeping the initial freq_factor value).
          */
         cpu_clk = of_clk_get(cpu_node, 0);
         if (!PTR_ERR_OR_ZERO(cpu_clk)) {
             per_cpu(freq_factor, cpu) =
                 clk_get_rate(cpu_clk) / 1000;
             clk_put(cpu_clk);
         }
     } else {
         if (raw_capacity) {
             pr_err("cpu_capacity: missing %pOF raw capacity\n",
                 cpu_node);
             pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
         }
         cap_parsing_failed = true;
         free_raw_capacity();
     }
 
     return !ret;
 }
 
 #ifdef CONFIG_ACPI_CPPC_LIB
 #include <acpi/cppc_acpi.h>
 
 void topology_init_cpu_capacity_cppc(void)
 {
     struct cppc_perf_caps perf_caps;
     int cpu;
 
     if (likely(acpi_disabled || !acpi_cpc_valid()))
         return;
 
     raw_capacity = kcalloc(num_possible_cpus(), sizeof(*raw_capacity),
                    GFP_KERNEL);
     if (!raw_capacity)
         return;
 
     for_each_possible_cpu(cpu) {
         if (!cppc_get_perf_caps(cpu, &perf_caps) &&
             (perf_caps.highest_perf >= perf_caps.nominal_perf) &&
             (perf_caps.highest_perf >= perf_caps.lowest_perf)) {
             raw_capacity[cpu] = perf_caps.highest_perf;
             pr_debug("cpu_capacity: CPU%d cpu_capacity=%u (raw).\n",
                  cpu, raw_capacity[cpu]);
             continue;
         }
 
         pr_err("cpu_capacity: CPU%d missing/invalid highest performance.\n", cpu);
         pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
         goto exit;
     }
 
     topology_normalize_cpu_scale();
     schedule_work(&update_topology_flags_work);
     pr_debug("cpu_capacity: cpu_capacity initialization done\n");
 
 exit:
     free_raw_capacity();
 }
 #endif
 
 #ifdef CONFIG_CPU_FREQ
 static cpumask_var_t cpus_to_visit;
 static void parsing_done_workfn(struct work_struct *work);
 static DECLARE_WORK(parsing_done_work, parsing_done_workfn);
 
 static int
 init_cpu_capacity_callback(struct notifier_block *nb,
                unsigned long val,
                void *data)
 {
     struct cpufreq_policy *policy = data;
     int cpu;
 
     if (!raw_capacity)
         return 0;
 
     if (val != CPUFREQ_CREATE_POLICY)
         return 0;
 
     pr_debug("cpu_capacity: init cpu capacity for CPUs [%*pbl] (to_visit=%*pbl)\n",
          cpumask_pr_args(policy->related_cpus),
          cpumask_pr_args(cpus_to_visit));
 
     cpumask_andnot(cpus_to_visit, cpus_to_visit, policy->related_cpus);
 
     for_each_cpu(cpu, policy->related_cpus)
         per_cpu(freq_factor, cpu) = policy->cpuinfo.max_freq / 1000;
 
     if (cpumask_empty(cpus_to_visit)) {
         topology_normalize_cpu_scale();
         schedule_work(&update_topology_flags_work);
         free_raw_capacity();
         pr_debug("cpu_capacity: parsing done\n");
         schedule_work(&parsing_done_work);
     }
 
     return 0;
 }
 
 static struct notifier_block init_cpu_capacity_notifier = {
     .notifier_call = init_cpu_capacity_callback,
 };
 
 static int __init register_cpufreq_notifier(void)
 {
     int ret;
 
     /*
      * On ACPI-based systems skip registering cpufreq notifier as cpufreq
      * information is not needed for cpu capacity initialization.
      */
     if (!acpi_disabled || !raw_capacity)
         return -EINVAL;
 
     if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))
         return -ENOMEM;
 
     cpumask_copy(cpus_to_visit, cpu_possible_mask);
 
     ret = cpufreq_register_notifier(&init_cpu_capacity_notifier,
                     CPUFREQ_POLICY_NOTIFIER);
 
     if (ret)
         free_cpumask_var(cpus_to_visit);
 
     return ret;
 }
 core_initcall(register_cpufreq_notifier);
 
 static void parsing_done_workfn(struct work_struct *work)
 {
     cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
                      CPUFREQ_POLICY_NOTIFIER);
     free_cpumask_var(cpus_to_visit);
 }
 
 #else
 core_initcall(free_raw_capacity);
 #endif
 
 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 /*
  * This function returns the logic cpu number of the node.
  * There are basically three kinds of return values:
  * (1) logic cpu number which is > 0.
  * (2) -ENODEV when the device tree(DT) node is valid and found in the DT but
  * there is no possible logical CPU in the kernel to match. This happens
  * when CONFIG_NR_CPUS is configure to be smaller than the number of
  * CPU nodes in DT. We need to just ignore this case.
  * (3) -1 if the node does not exist in the device tree
  */
 static int __init get_cpu_for_node(struct device_node *node)
 {
     struct device_node *cpu_node;
     int cpu;
 
     cpu_node = of_parse_phandle(node, "cpu", 0);
     if (!cpu_node)
         return -1;
 
     cpu = of_cpu_node_to_id(cpu_node);
     if (cpu >= 0)
         topology_parse_cpu_capacity(cpu_node, cpu);
     else
         pr_info("CPU node for %pOF exist but the possible cpu range is :%*pbl\n",
             cpu_node, cpumask_pr_args(cpu_possible_mask));
 
     of_node_put(cpu_node);
     return cpu;
 }
 
 static int __init parse_core(struct device_node *core, int package_id,
                  int cluster_id, int core_id)
 {
     char name[20];
     bool leaf = true;
     int i = 0;
     int cpu;
     struct device_node *t;
 
     do {
         snprintf(name, sizeof(name), "thread%d", i);
         t = of_get_child_by_name(core, name);
         if (t) {
             leaf = false;
             cpu = get_cpu_for_node(t);
             if (cpu >= 0) {
                 cpu_topology[cpu].package_id = package_id;
                 cpu_topology[cpu].cluster_id = cluster_id;
                 cpu_topology[cpu].core_id = core_id;
                 cpu_topology[cpu].thread_id = i;
             } else if (cpu != -ENODEV) {
                 pr_err("%pOF: Can't get CPU for thread\n", t);
                 of_node_put(t);
                 return -EINVAL;
             }
             of_node_put(t);
         }
         i++;
     } while (t);
 
     cpu = get_cpu_for_node(core);
     if (cpu >= 0) {
         if (!leaf) {
             pr_err("%pOF: Core has both threads and CPU\n",
                    core);
             return -EINVAL;
         }
 
         cpu_topology[cpu].package_id = package_id;
         cpu_topology[cpu].cluster_id = cluster_id;
         cpu_topology[cpu].core_id = core_id;
     } else if (leaf && cpu != -ENODEV) {
         pr_err("%pOF: Can't get CPU for leaf core\n", core);
         return -EINVAL;
     }
 
     return 0;
 }
 
 static int __init parse_cluster(struct device_node *cluster, int package_id,
                 int cluster_id, int depth)
 {
     char name[20];
     bool leaf = true;
     bool has_cores = false;
     struct device_node *c;
     int core_id = 0;
     int i, ret;
 
     /*
      * First check for child clusters; we currently ignore any
      * information about the nesting of clusters and present the
      * scheduler with a flat list of them.
      */
     i = 0;
     do {
         snprintf(name, sizeof(name), "cluster%d", i);
         c = of_get_child_by_name(cluster, name);
         if (c) {
             leaf = false;
             ret = parse_cluster(c, package_id, i, depth + 1);
             if (depth > 0)
                 pr_warn("Topology for clusters of clusters not yet supported\n");
             of_node_put(c);
             if (ret != 0)
                 return ret;
         }
         i++;
     } while (c);
 
     /* Now check for cores */
     i = 0;
     do {
         snprintf(name, sizeof(name), "core%d", i);
         c = of_get_child_by_name(cluster, name);
         if (c) {
             has_cores = true;
 
             if (depth == 0) {
                 pr_err("%pOF: cpu-map children should be clusters\n",
                        c);
                 of_node_put(c);
                 return -EINVAL;
             }
 
             if (leaf) {
                 ret = parse_core(c, package_id, cluster_id,
                          core_id++);
             } else {
                 pr_err("%pOF: Non-leaf cluster with core %s\n",
                        cluster, name);
                 ret = -EINVAL;
             }
 
             of_node_put(c);
             if (ret != 0)
                 return ret;
         }
         i++;
     } while (c);
 
     if (leaf && !has_cores)
         pr_warn("%pOF: empty cluster\n", cluster);
 
     return 0;
 }
 
 static int __init parse_socket(struct device_node *socket)
 {
     char name[20];
     struct device_node *c;
     bool has_socket = false;
     int package_id = 0, ret;
 
     do {
         snprintf(name, sizeof(name), "socket%d", package_id);
         c = of_get_child_by_name(socket, name);
         if (c) {
             has_socket = true;
             ret = parse_cluster(c, package_id, -1, 0);
             of_node_put(c);
             if (ret != 0)
                 return ret;
         }
         package_id++;
     } while (c);
 
     if (!has_socket)
         ret = parse_cluster(socket, 0, -1, 0);
 
     return ret;
 }
 
 static int __init parse_dt_topology(void)
 {
     struct device_node *cn, *map;
     int ret = 0;
     int cpu;
 
     cn = of_find_node_by_path("/cpus");
     if (!cn) {
         pr_err("No CPU information found in DT\n");
         return 0;
     }
 
     /*
      * When topology is provided cpu-map is essentially a root
      * cluster with restricted subnodes.
      */
     map = of_get_child_by_name(cn, "cpu-map");
     if (!map)
         goto out;
 
     ret = parse_socket(map);
     if (ret != 0)
         goto out_map;
 
     topology_normalize_cpu_scale();
 
     /*
      * Check that all cores are in the topology; the SMP code will
      * only mark cores described in the DT as possible.
      */
     for_each_possible_cpu(cpu)
         if (cpu_topology[cpu].package_id < 0) {
             ret = -EINVAL;
             break;
         }
 
 out_map:
     of_node_put(map);
 out:
     of_node_put(cn);
     return ret;
 }
 #endif
 
 /*
  * cpu topology table
  */
 struct cpu_topology cpu_topology[NR_CPUS];
 EXPORT_SYMBOL_GPL(cpu_topology);
 
 const struct cpumask *cpu_coregroup_mask(int cpu)
 {
     const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));
 
     /* Find the smaller of NUMA, core or LLC siblings */
     if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
         /* not numa in package, lets use the package siblings */
         core_mask = &cpu_topology[cpu].core_sibling;
     }
 
     if (last_level_cache_is_valid(cpu)) {
         if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
             core_mask = &cpu_topology[cpu].llc_sibling;
     }
 
     /*
      * For systems with no shared cpu-side LLC but with clusters defined,
      * extend core_mask to cluster_siblings. The sched domain builder will
      * then remove MC as redundant with CLS if SCHED_CLUSTER is enabled.
      */
     if (IS_ENABLED(CONFIG_SCHED_CLUSTER) &&
         cpumask_subset(core_mask, &cpu_topology[cpu].cluster_sibling))
         core_mask = &cpu_topology[cpu].cluster_sibling;
 
     return core_mask;
 }
 
 const struct cpumask *cpu_clustergroup_mask(int cpu)
 {
     /*
      * Forbid cpu_clustergroup_mask() to span more or the same CPUs as
      * cpu_coregroup_mask().
      */
     if (cpumask_subset(cpu_coregroup_mask(cpu),
                &cpu_topology[cpu].cluster_sibling))
         return topology_sibling_cpumask(cpu);
 
     return &cpu_topology[cpu].cluster_sibling;
 }
 
 void update_siblings_masks(unsigned int cpuid)
 {
     struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
     int cpu, ret;
 
     ret = detect_cache_attributes(cpuid);
     if (ret && ret != -ENOENT)
         pr_info("Early cacheinfo failed, ret = %d\n", ret);
 
     /* update core and thread sibling masks */
     for_each_online_cpu(cpu) {
         cpu_topo = &cpu_topology[cpu];
 
         if (last_level_cache_is_shared(cpu, cpuid)) {
             cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
             cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
         }
 
         if (cpuid_topo->package_id != cpu_topo->package_id)
             continue;
 
         cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
         cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
 
         if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
             continue;
 
         if (cpuid_topo->cluster_id >= 0) {
             cpumask_set_cpu(cpu, &cpuid_topo->cluster_sibling);
             cpumask_set_cpu(cpuid, &cpu_topo->cluster_sibling);
         }
 
         if (cpuid_topo->core_id != cpu_topo->core_id)
             continue;
 
         cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
         cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
     }
 }
 
 static void clear_cpu_topology(int cpu)
 {
     struct cpu_topology *cpu_topo = &cpu_topology[cpu];
 
     cpumask_clear(&cpu_topo->llc_sibling);
     cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);
 
     cpumask_clear(&cpu_topo->cluster_sibling);
     cpumask_set_cpu(cpu, &cpu_topo->cluster_sibling);
 
     cpumask_clear(&cpu_topo->core_sibling);
     cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
     cpumask_clear(&cpu_topo->thread_sibling);
     cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
 }
 
 void __init reset_cpu_topology(void)
 {
     unsigned int cpu;
 
     for_each_possible_cpu(cpu) {
         struct cpu_topology *cpu_topo = &cpu_topology[cpu];
 
         cpu_topo->thread_id = -1;
         cpu_topo->core_id = -1;
         cpu_topo->cluster_id = -1;
         cpu_topo->package_id = -1;
 
         clear_cpu_topology(cpu);
     }
 }
 
 void remove_cpu_topology(unsigned int cpu)
 {
     int sibling;
 
     for_each_cpu(sibling, topology_core_cpumask(cpu))
         cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
     for_each_cpu(sibling, topology_sibling_cpumask(cpu))
         cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
     for_each_cpu(sibling, topology_cluster_cpumask(cpu))
         cpumask_clear_cpu(cpu, topology_cluster_cpumask(sibling));
     for_each_cpu(sibling, topology_llc_cpumask(cpu))
         cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
 
     clear_cpu_topology(cpu);
 }
 
 __weak int __init parse_acpi_topology(void)
 {
     return 0;
 }
 
 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 void __init init_cpu_topology(void)
 {
     int ret;
 
     reset_cpu_topology();
     ret = parse_acpi_topology();
     if (!ret)
         ret = of_have_populated_dt() && parse_dt_topology();
 
     if (ret) {
         /*
          * Discard anything that was parsed if we hit an error so we
          * don't use partial information.
          */
         reset_cpu_topology();
         return;
     }
 }
 #endif

This page was automatically generated by the 2.1.0 LXR engine. The LXR team