linux/tools/perf/util/cpumap.c

115 lines
2.0 KiB
C

#include "util.h"
#include "../perf.h"
#include "cpumap.h"
#include <assert.h>
#include <stdio.h>
int cpumap[MAX_NR_CPUS];
static int default_cpu_map(void)
{
int nr_cpus, i;
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
assert((int)nr_cpus >= 0);
for (i = 0; i < nr_cpus; ++i)
cpumap[i] = i;
return nr_cpus;
}
static int read_all_cpu_map(void)
{
FILE *onlnf;
int nr_cpus = 0;
int n, cpu, prev;
char sep;
onlnf = fopen("/sys/devices/system/cpu/online", "r");
if (!onlnf)
return default_cpu_map();
sep = 0;
prev = -1;
for (;;) {
n = fscanf(onlnf, "%u%c", &cpu, &sep);
if (n <= 0)
break;
if (prev >= 0) {
assert(nr_cpus + cpu - prev - 1 < MAX_NR_CPUS);
while (++prev < cpu)
cpumap[nr_cpus++] = prev;
}
assert (nr_cpus < MAX_NR_CPUS);
cpumap[nr_cpus++] = cpu;
if (n == 2 && sep == '-')
prev = cpu;
else
prev = -1;
if (n == 1 || sep == '\n')
break;
}
fclose(onlnf);
if (nr_cpus > 0)
return nr_cpus;
return default_cpu_map();
}
int read_cpu_map(const char *cpu_list)
{
unsigned long start_cpu, end_cpu = 0;
char *p = NULL;
int i, nr_cpus = 0;
if (!cpu_list)
return read_all_cpu_map();
if (!isdigit(*cpu_list))
goto invalid;
while (isdigit(*cpu_list)) {
p = NULL;
start_cpu = strtoul(cpu_list, &p, 0);
if (start_cpu >= INT_MAX
|| (*p != '\0' && *p != ',' && *p != '-'))
goto invalid;
if (*p == '-') {
cpu_list = ++p;
p = NULL;
end_cpu = strtoul(cpu_list, &p, 0);
if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
goto invalid;
if (end_cpu < start_cpu)
goto invalid;
} else {
end_cpu = start_cpu;
}
for (; start_cpu <= end_cpu; start_cpu++) {
/* check for duplicates */
for (i = 0; i < nr_cpus; i++)
if (cpumap[i] == (int)start_cpu)
goto invalid;
assert(nr_cpus < MAX_NR_CPUS);
cpumap[nr_cpus++] = (int)start_cpu;
}
if (*p)
++p;
cpu_list = p;
}
if (nr_cpus > 0)
return nr_cpus;
return default_cpu_map();
invalid:
return -1;
}