tools/perf/util/cpumap.c

   1 #include "util.h"
   2 #include "../perf.h"
   3 #include "cpumap.h"
   4 #include <assert.h>
   5 #include <stdio.h>
   6
   7 static 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
  28 static 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
  41 static 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();
  96 out_free_tmp:
  97         free(tmp_cpus);
  98         fclose(onlnf);
  99         return cpus;
 100 }
 101
 102 struct 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();
 163 invalid:
 164         free(tmp_cpus);
 165 out:
 166         return cpus;
 167 }
 168
 169 struct 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
 181 void cpu_map__delete(struct cpu_map *map)
 182 {
 183         free(map);
 184 }