linuxdebug/arch/parisc/kernel/topology.c

88 lines
2.2 KiB
C

/*
* arch/parisc/kernel/topology.c
*
* Copyright (C) 2017 Helge Deller <deller@gmx.de>
*
* based on arch/arm/kernel/topology.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/percpu.h>
#include <linux/sched.h>
#include <linux/sched/topology.h>
#include <linux/cpu.h>
#include <asm/topology.h>
#include <asm/sections.h>
static DEFINE_PER_CPU(struct cpu, cpu_devices);
/*
* store_cpu_topology is called at boot when only one cpu is running
* and with the mutex cpu_hotplug.lock locked, when several cpus have booted,
* which prevents simultaneous write access to cpu_topology array
*/
void store_cpu_topology(unsigned int cpuid)
{
struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
struct cpuinfo_parisc *p;
int max_socket = -1;
unsigned long cpu;
/* If the cpu topology has been already set, just return */
if (cpuid_topo->core_id != -1)
return;
#ifdef CONFIG_HOTPLUG_CPU
per_cpu(cpu_devices, cpuid).hotpluggable = 1;
#endif
if (register_cpu(&per_cpu(cpu_devices, cpuid), cpuid))
pr_warn("Failed to register CPU%d device", cpuid);
/* create cpu topology mapping */
cpuid_topo->thread_id = -1;
cpuid_topo->core_id = 0;
p = &per_cpu(cpu_data, cpuid);
for_each_online_cpu(cpu) {
const struct cpuinfo_parisc *cpuinfo = &per_cpu(cpu_data, cpu);
if (cpu == cpuid) /* ignore current cpu */
continue;
if (cpuinfo->cpu_loc == p->cpu_loc) {
cpuid_topo->core_id = cpu_topology[cpu].core_id;
if (p->cpu_loc) {
cpuid_topo->core_id++;
cpuid_topo->package_id = cpu_topology[cpu].package_id;
continue;
}
}
if (cpuid_topo->package_id == -1)
max_socket = max(max_socket, cpu_topology[cpu].package_id);
}
if (cpuid_topo->package_id == -1)
cpuid_topo->package_id = max_socket + 1;
update_siblings_masks(cpuid);
pr_info("CPU%u: cpu core %d of socket %d\n",
cpuid,
cpu_topology[cpuid].core_id,
cpu_topology[cpuid].package_id);
}
/*
* init_cpu_topology is called at boot when only one cpu is running
* which prevent simultaneous write access to cpu_topology array
*/
void __init init_cpu_topology(void)
{
reset_cpu_topology();
}