1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
#include <stdio.h>
#include <stdlib.h>
#include <perf/cpumap.h>
#include <util/cpumap.h>
#include <internal/cpumap.h>
#include <api/fs/fs.h>
#include <errno.h>
#include "debug.h"
#include "header.h"
#define MIDR "/regs/identification/midr_el1"
#define MIDR_SIZE 19
#define MIDR_REVISION_MASK 0xf
#define MIDR_VARIANT_SHIFT 20
#define MIDR_VARIANT_MASK (0xf << MIDR_VARIANT_SHIFT)
static int _get_cpuid(char *buf, size_t sz, struct perf_cpu_map *cpus)
{
const char *sysfs = sysfs__mountpoint();
u64 midr = 0;
int cpu;
if (!sysfs || sz < MIDR_SIZE)
return EINVAL;
cpus = perf_cpu_map__get(cpus);
for (cpu = 0; cpu < perf_cpu_map__nr(cpus); cpu++) {
char path[PATH_MAX];
FILE *file;
scnprintf(path, PATH_MAX, "%s/devices/system/cpu/cpu%d"MIDR,
sysfs, cpus->map[cpu]);
file = fopen(path, "r");
if (!file) {
pr_debug("fopen failed for file %s\n", path);
continue;
}
if (!fgets(buf, MIDR_SIZE, file)) {
fclose(file);
continue;
}
fclose(file);
/* Ignore/clear Variant[23:20] and
* Revision[3:0] of MIDR
*/
midr = strtoul(buf, NULL, 16);
midr &= (~(MIDR_VARIANT_MASK | MIDR_REVISION_MASK));
scnprintf(buf, MIDR_SIZE, "0x%016lx", midr);
/* got midr break loop */
break;
}
perf_cpu_map__put(cpus);
if (!midr)
return EINVAL;
return 0;
}
int get_cpuid(char *buf, size_t sz)
{
struct perf_cpu_map *cpus = perf_cpu_map__new(NULL);
int ret;
if (!cpus)
return EINVAL;
ret = _get_cpuid(buf, sz, cpus);
perf_cpu_map__put(cpus);
return ret;
}
char *get_cpuid_str(struct perf_pmu *pmu)
{
char *buf = NULL;
int res;
if (!pmu || !pmu->cpus)
return NULL;
buf = malloc(MIDR_SIZE);
if (!buf)
return NULL;
/* read midr from list of cpus mapped to this pmu */
res = _get_cpuid(buf, MIDR_SIZE, pmu->cpus);
if (res) {
pr_err("failed to get cpuid string for PMU %s\n", pmu->name);
free(buf);
buf = NULL;
}
return buf;
}
|
