linux-stable/include/linux/arch_topology.h
Ionela Voinescu 9924fbb51e arch_topology: obtain cpu capacity using information from CPPC
Define topology_init_cpu_capacity_cppc() to use highest performance
values from _CPC objects to obtain and set maximum capacity information
for each CPU. acpi_cppc_processor_probe() is a good point at which to
trigger the initialization of CPU (u-arch) capacity values, as at this
point the highest performance values can be obtained from each CPU's
_CPC objects. Architectures can therefore use this functionality
through arch_init_invariance_cppc().

The performance scale used by CPPC is a unified scale for all CPUs in
the system. Therefore, by obtaining the raw highest performance values
from the _CPC objects, and normalizing them on the [0, 1024] capacity
scale, used by the task scheduler, we obtain the CPU capacity of each
CPU.

While an ACPI Notify(0x85) could alert about a change in the highest
performance value, which should in turn retrigger the CPU capacity
computations, this notification is not currently handled by the ACPI
processor driver. When supported, a call to arch_init_invariance_cppc()
would perform the update.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-10 20:21:58 +01:00

98 lines
2.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* include/linux/arch_topology.h - arch specific cpu topology information
*/
#ifndef _LINUX_ARCH_TOPOLOGY_H_
#define _LINUX_ARCH_TOPOLOGY_H_
#include <linux/types.h>
#include <linux/percpu.h>
void topology_normalize_cpu_scale(void);
int topology_update_cpu_topology(void);
#ifdef CONFIG_ACPI_CPPC_LIB
void topology_init_cpu_capacity_cppc(void);
#endif
struct device_node;
bool topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu);
DECLARE_PER_CPU(unsigned long, cpu_scale);
static inline unsigned long topology_get_cpu_scale(int cpu)
{
return per_cpu(cpu_scale, cpu);
}
void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity);
DECLARE_PER_CPU(unsigned long, arch_freq_scale);
static inline unsigned long topology_get_freq_scale(int cpu)
{
return per_cpu(arch_freq_scale, cpu);
}
void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq,
unsigned long max_freq);
bool topology_scale_freq_invariant(void);
enum scale_freq_source {
SCALE_FREQ_SOURCE_CPUFREQ = 0,
SCALE_FREQ_SOURCE_ARCH,
SCALE_FREQ_SOURCE_CPPC,
};
struct scale_freq_data {
enum scale_freq_source source;
void (*set_freq_scale)(void);
};
void topology_scale_freq_tick(void);
void topology_set_scale_freq_source(struct scale_freq_data *data, const struct cpumask *cpus);
void topology_clear_scale_freq_source(enum scale_freq_source source, const struct cpumask *cpus);
DECLARE_PER_CPU(unsigned long, thermal_pressure);
static inline unsigned long topology_get_thermal_pressure(int cpu)
{
return per_cpu(thermal_pressure, cpu);
}
void topology_update_thermal_pressure(const struct cpumask *cpus,
unsigned long capped_freq);
struct cpu_topology {
int thread_id;
int core_id;
int cluster_id;
int package_id;
int llc_id;
cpumask_t thread_sibling;
cpumask_t core_sibling;
cpumask_t cluster_sibling;
cpumask_t llc_sibling;
};
#ifdef CONFIG_GENERIC_ARCH_TOPOLOGY
extern struct cpu_topology cpu_topology[NR_CPUS];
#define topology_physical_package_id(cpu) (cpu_topology[cpu].package_id)
#define topology_cluster_id(cpu) (cpu_topology[cpu].cluster_id)
#define topology_core_id(cpu) (cpu_topology[cpu].core_id)
#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling)
#define topology_sibling_cpumask(cpu) (&cpu_topology[cpu].thread_sibling)
#define topology_cluster_cpumask(cpu) (&cpu_topology[cpu].cluster_sibling)
#define topology_llc_cpumask(cpu) (&cpu_topology[cpu].llc_sibling)
void init_cpu_topology(void);
void store_cpu_topology(unsigned int cpuid);
const struct cpumask *cpu_coregroup_mask(int cpu);
const struct cpumask *cpu_clustergroup_mask(int cpu);
void update_siblings_masks(unsigned int cpu);
void remove_cpu_topology(unsigned int cpuid);
void reset_cpu_topology(void);
int parse_acpi_topology(void);
#endif
#endif /* _LINUX_ARCH_TOPOLOGY_H_ */