linux-stable/arch/x86/kernel/cpu/proc.c
Linus Torvalds ea0ee33988 Revert "x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"
This reverts commit 941f5f0f6e.

Sadly, it turns out that we really can't just do the cross-CPU IPI to
all CPU's to get their proper frequencies, because it's much too
expensive on systems with lots of cores.

So we'll have to revert this for now, and revisit it using a smarter
model (probably doing one system-wide IPI at open time, and doing all
the frequency calculations in parallel).

Reported-by: WANG Chao <chao.wang@ucloud.cn>
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Rafael J Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-10 11:19:11 -08:00

163 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/smp.h>
#include <linux/timex.h>
#include <linux/string.h>
#include <linux/seq_file.h>
#include <linux/cpufreq.h>
/*
* Get CPU information for use by the procfs.
*/
static void show_cpuinfo_core(struct seq_file *m, struct cpuinfo_x86 *c,
unsigned int cpu)
{
#ifdef CONFIG_SMP
seq_printf(m, "physical id\t: %d\n", c->phys_proc_id);
seq_printf(m, "siblings\t: %d\n",
cpumask_weight(topology_core_cpumask(cpu)));
seq_printf(m, "core id\t\t: %d\n", c->cpu_core_id);
seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
seq_printf(m, "apicid\t\t: %d\n", c->apicid);
seq_printf(m, "initial apicid\t: %d\n", c->initial_apicid);
#endif
}
#ifdef CONFIG_X86_32
static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
{
seq_printf(m,
"fdiv_bug\t: %s\n"
"f00f_bug\t: %s\n"
"coma_bug\t: %s\n"
"fpu\t\t: %s\n"
"fpu_exception\t: %s\n"
"cpuid level\t: %d\n"
"wp\t\t: yes\n",
static_cpu_has_bug(X86_BUG_FDIV) ? "yes" : "no",
static_cpu_has_bug(X86_BUG_F00F) ? "yes" : "no",
static_cpu_has_bug(X86_BUG_COMA) ? "yes" : "no",
static_cpu_has(X86_FEATURE_FPU) ? "yes" : "no",
static_cpu_has(X86_FEATURE_FPU) ? "yes" : "no",
c->cpuid_level);
}
#else
static void show_cpuinfo_misc(struct seq_file *m, struct cpuinfo_x86 *c)
{
seq_printf(m,
"fpu\t\t: yes\n"
"fpu_exception\t: yes\n"
"cpuid level\t: %d\n"
"wp\t\t: yes\n",
c->cpuid_level);
}
#endif
static int show_cpuinfo(struct seq_file *m, void *v)
{
struct cpuinfo_x86 *c = v;
unsigned int cpu;
int i;
cpu = c->cpu_index;
seq_printf(m, "processor\t: %u\n"
"vendor_id\t: %s\n"
"cpu family\t: %d\n"
"model\t\t: %u\n"
"model name\t: %s\n",
cpu,
c->x86_vendor_id[0] ? c->x86_vendor_id : "unknown",
c->x86,
c->x86_model,
c->x86_model_id[0] ? c->x86_model_id : "unknown");
if (c->x86_mask || c->cpuid_level >= 0)
seq_printf(m, "stepping\t: %d\n", c->x86_mask);
else
seq_puts(m, "stepping\t: unknown\n");
if (c->microcode)
seq_printf(m, "microcode\t: 0x%x\n", c->microcode);
if (cpu_has(c, X86_FEATURE_TSC)) {
unsigned int freq = cpufreq_quick_get(cpu);
if (!freq)
freq = cpu_khz;
seq_printf(m, "cpu MHz\t\t: %u.%03u\n",
freq / 1000, (freq % 1000));
}
/* Cache size */
if (c->x86_cache_size >= 0)
seq_printf(m, "cache size\t: %d KB\n", c->x86_cache_size);
show_cpuinfo_core(m, c, cpu);
show_cpuinfo_misc(m, c);
seq_puts(m, "flags\t\t:");
for (i = 0; i < 32*NCAPINTS; i++)
if (cpu_has(c, i) && x86_cap_flags[i] != NULL)
seq_printf(m, " %s", x86_cap_flags[i]);
seq_puts(m, "\nbugs\t\t:");
for (i = 0; i < 32*NBUGINTS; i++) {
unsigned int bug_bit = 32*NCAPINTS + i;
if (cpu_has_bug(c, bug_bit) && x86_bug_flags[i])
seq_printf(m, " %s", x86_bug_flags[i]);
}
seq_printf(m, "\nbogomips\t: %lu.%02lu\n",
c->loops_per_jiffy/(500000/HZ),
(c->loops_per_jiffy/(5000/HZ)) % 100);
#ifdef CONFIG_X86_64
if (c->x86_tlbsize > 0)
seq_printf(m, "TLB size\t: %d 4K pages\n", c->x86_tlbsize);
#endif
seq_printf(m, "clflush size\t: %u\n", c->x86_clflush_size);
seq_printf(m, "cache_alignment\t: %d\n", c->x86_cache_alignment);
seq_printf(m, "address sizes\t: %u bits physical, %u bits virtual\n",
c->x86_phys_bits, c->x86_virt_bits);
seq_puts(m, "power management:");
for (i = 0; i < 32; i++) {
if (c->x86_power & (1 << i)) {
if (i < ARRAY_SIZE(x86_power_flags) &&
x86_power_flags[i])
seq_printf(m, "%s%s",
x86_power_flags[i][0] ? " " : "",
x86_power_flags[i]);
else
seq_printf(m, " [%d]", i);
}
}
seq_puts(m, "\n\n");
return 0;
}
static void *c_start(struct seq_file *m, loff_t *pos)
{
*pos = cpumask_next(*pos - 1, cpu_online_mask);
if ((*pos) < nr_cpu_ids)
return &cpu_data(*pos);
return NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
(*pos)++;
return c_start(m, pos);
}
static void c_stop(struct seq_file *m, void *v)
{
}
const struct seq_operations cpuinfo_op = {
.start = c_start,
.next = c_next,
.stop = c_stop,
.show = show_cpuinfo,
};