linux/tools/perf/util/cpumap.c
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   1#include "util.h"
   2#include "../perf.h"
   3#include "cpumap.h"
   4#include <assert.h>
   5#include <stdio.h>
   6
   7static struct cpu_map *cpu_map__default_new(void)
   8{
   9        struct cpu_map *cpus;
  10        int nr_cpus;
  11
  12        nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
  13        if (nr_cpus < 0)
  14                return NULL;
  15
  16        cpus = malloc(sizeof(*cpus) + nr_cpus * sizeof(int));
  17        if (cpus != NULL) {
  18                int i;
  19                for (i = 0; i < nr_cpus; ++i)
  20                        cpus->map[i] = i;
  21
  22                cpus->nr = nr_cpus;
  23        }
  24
  25        return cpus;
  26}
  27
  28static struct cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
  29{
  30        size_t payload_size = nr_cpus * sizeof(int);
  31        struct cpu_map *cpus = malloc(sizeof(*cpus) + payload_size);
  32
  33        if (cpus != NULL) {
  34                cpus->nr = nr_cpus;
  35                memcpy(cpus->map, tmp_cpus, payload_size);
  36        }
  37
  38        return cpus;
  39}
  40
  41static struct cpu_map *cpu_map__read_all_cpu_map(void)
  42{
  43        struct cpu_map *cpus = NULL;
  44        FILE *onlnf;
  45        int nr_cpus = 0;
  46        int *tmp_cpus = NULL, *tmp;
  47        int max_entries = 0;
  48        int n, cpu, prev;
  49        char sep;
  50
  51        onlnf = fopen("/sys/devices/system/cpu/online", "r");
  52        if (!onlnf)
  53                return cpu_map__default_new();
  54
  55        sep = 0;
  56        prev = -1;
  57        for (;;) {
  58                n = fscanf(onlnf, "%u%c", &cpu, &sep);
  59                if (n <= 0)
  60                        break;
  61                if (prev >= 0) {
  62                        int new_max = nr_cpus + cpu - prev - 1;
  63
  64                        if (new_max >= max_entries) {
  65                                max_entries = new_max + MAX_NR_CPUS / 2;
  66                                tmp = realloc(tmp_cpus, max_entries * sizeof(int));
  67                                if (tmp == NULL)
  68                                        goto out_free_tmp;
  69                                tmp_cpus = tmp;
  70                        }
  71
  72                        while (++prev < cpu)
  73                                tmp_cpus[nr_cpus++] = prev;
  74                }
  75                if (nr_cpus == max_entries) {
  76                        max_entries += MAX_NR_CPUS;
  77                        tmp = realloc(tmp_cpus, max_entries * sizeof(int));
  78                        if (tmp == NULL)
  79                                goto out_free_tmp;
  80                        tmp_cpus = tmp;
  81                }
  82
  83                tmp_cpus[nr_cpus++] = cpu;
  84                if (n == 2 && sep == '-')
  85                        prev = cpu;
  86                else
  87                        prev = -1;
  88                if (n == 1 || sep == '\n')
  89                        break;
  90        }
  91
  92        if (nr_cpus > 0)
  93                cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
  94        else
  95                cpus = cpu_map__default_new();
  96out_free_tmp:
  97        free(tmp_cpus);
  98        fclose(onlnf);
  99        return cpus;
 100}
 101
 102struct cpu_map *cpu_map__new(const char *cpu_list)
 103{
 104        struct cpu_map *cpus = NULL;
 105        unsigned long start_cpu, end_cpu = 0;
 106        char *p = NULL;
 107        int i, nr_cpus = 0;
 108        int *tmp_cpus = NULL, *tmp;
 109        int max_entries = 0;
 110
 111        if (!cpu_list)
 112                return cpu_map__read_all_cpu_map();
 113
 114        if (!isdigit(*cpu_list))
 115                goto out;
 116
 117        while (isdigit(*cpu_list)) {
 118                p = NULL;
 119                start_cpu = strtoul(cpu_list, &p, 0);
 120                if (start_cpu >= INT_MAX
 121                    || (*p != '\0' && *p != ',' && *p != '-'))
 122                        goto invalid;
 123
 124                if (*p == '-') {
 125                        cpu_list = ++p;
 126                        p = NULL;
 127                        end_cpu = strtoul(cpu_list, &p, 0);
 128
 129                        if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
 130                                goto invalid;
 131
 132                        if (end_cpu < start_cpu)
 133                                goto invalid;
 134                } else {
 135                        end_cpu = start_cpu;
 136                }
 137
 138                for (; start_cpu <= end_cpu; start_cpu++) {
 139                        /* check for duplicates */
 140                        for (i = 0; i < nr_cpus; i++)
 141                                if (tmp_cpus[i] == (int)start_cpu)
 142                                        goto invalid;
 143
 144                        if (nr_cpus == max_entries) {
 145                                max_entries += MAX_NR_CPUS;
 146                                tmp = realloc(tmp_cpus, max_entries * sizeof(int));
 147                                if (tmp == NULL)
 148                                        goto invalid;
 149                                tmp_cpus = tmp;
 150                        }
 151                        tmp_cpus[nr_cpus++] = (int)start_cpu;
 152                }
 153                if (*p)
 154                        ++p;
 155
 156                cpu_list = p;
 157        }
 158
 159        if (nr_cpus > 0)
 160                cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
 161        else
 162                cpus = cpu_map__default_new();
 163invalid:
 164        free(tmp_cpus);
 165out:
 166        return cpus;
 167}
 168
 169struct cpu_map *cpu_map__dummy_new(void)
 170{
 171        struct cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(int));
 172
 173        if (cpus != NULL) {
 174                cpus->nr = 1;
 175                cpus->map[0] = -1;
 176        }
 177
 178        return cpus;
 179}
 180
 181void cpu_map__delete(struct cpu_map *map)
 182{
 183        free(map);
 184}
 185