sys-utils/chcpu.c

   1 /*
   2  * chcpu - CPU configuration tool
   3  *
   4  * Copyright IBM Corp. 2011
   5  * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it would be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software Foundation,
  19  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <ctype.h>
  23 #include <dirent.h>
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <getopt.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <sys/utsname.h>
  31 #include <unistd.h>
  32 #include <stdarg.h>
  33 #include <sys/types.h>
  34 #include <sys/stat.h>
  35
  36 #include "cpuset.h"
  37 #include "nls.h"
  38 #include "xalloc.h"
  39 #include "c.h"
  40 #include "strutils.h"
  41 #include "bitops.h"
  42 #include "path.h"
  43
  44 #define _PATH_SYS_CPU           "/sys/devices/system/cpu"
  45 #define _PATH_SYS_CPU_ONLINE    _PATH_SYS_CPU "/online"
  46 #define _PATH_SYS_CPU_RESCAN    _PATH_SYS_CPU "/rescan"
  47 #define _PATH_SYS_CPU_DISPATCH  _PATH_SYS_CPU "/dispatching"
  48
  49 static cpu_set_t *onlinecpus;
  50 static size_t maxcpus;
  51
  52 #define is_cpu_online(cpu) (CPU_ISSET_S((cpu), CPU_ALLOC_SIZE(maxcpus), onlinecpus))
  53 #define num_online_cpus()  (CPU_COUNT_S(CPU_ALLOC_SIZE(maxcpus), onlinecpus))
  54
  55 enum {
  56         CMD_CPU_ENABLE  = 0,
  57         CMD_CPU_DISABLE,
  58         CMD_CPU_CONFIGURE,
  59         CMD_CPU_DECONFIGURE,
  60         CMD_CPU_RESCAN,
  61         CMD_CPU_DISPATCH_HORIZONTAL,
  62         CMD_CPU_DISPATCH_VERTICAL,
  63 };
  64
  65 static int cpu_enable(cpu_set_t *cpu_set, size_t setsize, int enable)
  66 {
  67         unsigned int cpu;
  68         int online, rc;
  69         int configured = -1;
  70
  71         for (cpu = 0; cpu < setsize; cpu++) {
  72                 if (!CPU_ISSET(cpu, cpu_set))
  73                         continue;
  74                 if (!path_exist(_PATH_SYS_CPU "/cpu%d", cpu)) {
  75                         printf(_("CPU %d does not exist\n"), cpu);
  76                         continue;
  77                 }
  78                 if (!path_exist(_PATH_SYS_CPU "/cpu%d/online", cpu)) {
  79                         printf(_("CPU %d is not hot pluggable\n"), cpu);
  80                         continue;
  81                 }
  82                 online = path_getnum(_PATH_SYS_CPU "/cpu%d/online", cpu);
  83                 if ((online == 1) && (enable == 1)) {
  84                         printf(_("CPU %d is already enabled\n"), cpu);
  85                         continue;
  86                 }
  87                 if ((online == 0) && (enable == 0)) {
  88                         printf(_("CPU %d is already disabled\n"), cpu);
  89                         continue;
  90                 }
  91                 if (path_exist(_PATH_SYS_CPU "/cpu%d/configure", cpu))
  92                         configured = path_getnum(_PATH_SYS_CPU "/cpu%d/configure", cpu);
  93                 if (enable) {
  94                         rc = path_writestr("1", _PATH_SYS_CPU "/cpu%d/online", cpu);
  95                         if ((rc == -1) && (configured == 0))
  96                                 printf(_("CPU %d enable failed "
  97                                          "(CPU is deconfigured)\n"), cpu);
  98                         else if (rc == -1)
  99                                 printf(_("CPU %d enable failed (%m)\n"), cpu);
 100                         else
 101                                 printf(_("CPU %d enabled\n"), cpu);
 102                 } else {
 103                         if (onlinecpus && num_online_cpus() == 1) {
 104                                 printf(_("CPU %d disable failed "
 105                                          "(last enabled CPU)\n"), cpu);
 106                                 continue;
 107                         }
 108                         rc = path_writestr("0", _PATH_SYS_CPU "/cpu%d/online", cpu);
 109                         if (rc == -1)
 110                                 printf(_("CPU %d disable failed (%m)\n"), cpu);
 111                         else {
 112                                 printf(_("CPU %d disabled\n"), cpu);
 113                                 if (onlinecpus)
 114                                         CPU_CLR(cpu, onlinecpus);
 115                         }
 116                 }
 117         }
 118         return EXIT_SUCCESS;
 119 }
 120
 121 static int cpu_rescan(void)
 122 {
 123         if (!path_exist(_PATH_SYS_CPU_RESCAN))
 124                 errx(EXIT_FAILURE, _("This system does not support rescanning of CPUs"));
 125         if (path_writestr("1", _PATH_SYS_CPU_RESCAN) == -1)
 126                 err(EXIT_FAILURE, _("Failed to trigger rescan of CPUs"));
 127         printf(_("Triggered rescan of CPUs\n"));
 128         return EXIT_SUCCESS;
 129 }
 130
 131 static int cpu_set_dispatch(int mode)
 132 {
 133         if (!path_exist(_PATH_SYS_CPU_DISPATCH))
 134                 errx(EXIT_FAILURE, _("This system does not support setting "
 135                                      "the dispatching mode of CPUs"));
 136         if (mode == 0) {
 137                 if (path_writestr("0", _PATH_SYS_CPU_DISPATCH) == -1)
 138                         err(EXIT_FAILURE, _("Failed to set horizontal dispatch mode"));
 139                 printf(_("Succesfully set horizontal dispatching mode\n"));
 140         } else {
 141                 if (path_writestr("1", _PATH_SYS_CPU_DISPATCH) == -1)
 142                         err(EXIT_FAILURE, _("Failed to set vertical dispatch mode"));
 143                 printf(_("Succesfully set vertical dispatching mode\n"));
 144         }
 145         return EXIT_SUCCESS;
 146 }
 147
 148 static int cpu_configure(cpu_set_t *cpu_set, size_t setsize, int configure)
 149 {
 150         unsigned int cpu;
 151         int rc, current;
 152
 153         for (cpu = 0; cpu < setsize; cpu++) {
 154                 if (!CPU_ISSET(cpu, cpu_set))
 155                         continue;
 156                 if (!path_exist(_PATH_SYS_CPU "/cpu%d", cpu)) {
 157                         printf(_("CPU %d does not exist\n"), cpu);
 158                         continue;
 159                 }
 160                 if (!path_exist(_PATH_SYS_CPU "/cpu%d/configure", cpu)) {
 161                         printf(_("CPU %d is not configurable\n"), cpu);
 162                         continue;
 163                 }
 164                 current = path_getnum(_PATH_SYS_CPU "/cpu%d/configure", cpu);
 165                 if ((current == 1) && (configure == 1)) {
 166                         printf(_("CPU %d is already configured\n"), cpu);
 167                         continue;
 168                 }
 169                 if ((current == 0) && (configure == 0)) {
 170                         printf(_("CPU %d is already deconfigured\n"), cpu);
 171                         continue;
 172                 }
 173                 if ((current == 1) && (configure == 0) && onlinecpus &&
 174                     is_cpu_online(cpu)) {
 175                         printf(_("CPU %d deconfigure failed "
 176                                  "(CPU is enabled)\n"), cpu);
 177                         continue;
 178                 }
 179                 if (configure) {
 180                         rc = path_writestr("1", _PATH_SYS_CPU "/cpu%d/configure", cpu);
 181                         if (rc == -1)
 182                                 printf(_("CPU %d configure failed (%m)\n"), cpu);
 183                         else
 184                                 printf(_("CPU %d configured\n"), cpu);
 185                 } else {
 186                         rc = path_writestr("0", _PATH_SYS_CPU "/cpu%d/configure", cpu);
 187                         if (rc == -1)
 188                                 printf(_("CPU %d deconfigure failed (%m)\n"), cpu);
 189                         else
 190                                 printf(_("CPU %d deconfigured\n"), cpu);
 191                 }
 192         }
 193         return EXIT_SUCCESS;
 194 }
 195
 196 static void cpu_parse(char *cpu_string, cpu_set_t *cpu_set, size_t setsize)
 197 {
 198         int rc;
 199
 200         rc = cpulist_parse(cpu_string, cpu_set, setsize, 1);
 201         if (rc == 0)
 202                 return;
 203         if (rc == 2)
 204                 errx(EXIT_FAILURE, _("invalid CPU number in CPU list: %s"), cpu_string);
 205         errx(EXIT_FAILURE, _("failed to parse CPU list: %s"), cpu_string);
 206 }
 207
 208 static void __attribute__((__noreturn__)) usage(FILE *out)
 209 {
 210         fprintf(out, _(
 211                 "\nUsage:\n"
 212                 " %s [options]\n"), program_invocation_short_name);
 213
 214         puts(_( "\nOptions:\n"
 215                 "  -h, --help                    print this help\n"
 216                 "  -e, --enable <cpu-list>       enable cpus\n"
 217                 "  -d, --disable <cpu-list>      disable cpus\n"
 218                 "  -c, --configure <cpu-list>    configure cpus\n"
 219                 "  -g, --deconfigure <cpu-list>  deconfigure cpus\n"
 220                 "  -p, --dispatch <mode>         set dispatching mode\n"
 221                 "  -r, --rescan                  trigger rescan of cpus\n"
 222                 "  -V, --version                 output version information and exit\n"));
 223
 224         exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
 225 }
 226
 227 int main(int argc, char *argv[])
 228 {
 229         cpu_set_t *cpu_set;
 230         size_t setsize;
 231         int cmd = -1;
 232         int c;
 233
 234         static const struct option longopts[] = {
 235                 { "configure",  required_argument, 0, 'c' },
 236                 { "deconfigure",required_argument, 0, 'g' },
 237                 { "disable",    required_argument, 0, 'd' },
 238                 { "dispatch",   required_argument, 0, 'p' },
 239                 { "enable",     required_argument, 0, 'e' },
 240                 { "help",       no_argument,       0, 'h' },
 241                 { "rescan",     no_argument,       0, 'r' },
 242                 { "version",    no_argument,       0, 'V' },
 243                 { NULL,         0, 0, 0 }
 244         };
 245
 246         setlocale(LC_ALL, "");
 247         bindtextdomain(PACKAGE, LOCALEDIR);
 248         textdomain(PACKAGE);
 249
 250         maxcpus = get_max_number_of_cpus();
 251         if (maxcpus <= 0)
 252                 errx(EXIT_FAILURE, _("cannot determine NR_CPUS; aborting"));
 253         if (path_exist(_PATH_SYS_CPU_ONLINE))
 254                 onlinecpus = path_cpulist(maxcpus, _PATH_SYS_CPU_ONLINE);
 255         setsize = CPU_ALLOC_SIZE(maxcpus);
 256         cpu_set = CPU_ALLOC(maxcpus);
 257         if (!cpu_set)
 258                 err(EXIT_FAILURE, _("cpuset_alloc failed"));
 259
 260         while ((c = getopt_long(argc, argv, "c:d:e:g:hp:rV", longopts, NULL)) != -1) {
 261                 if (cmd != -1 && strchr("cdegpr", c))
 262                         errx(EXIT_FAILURE,
 263                              _("configure, deconfigure, disable, dispatch, enable "
 264                                "and rescan are mutually exclusive"));
 265                 switch (c) {
 266                 case 'c':
 267                         cmd = CMD_CPU_CONFIGURE;
 268                         cpu_parse(argv[optind - 1], cpu_set, setsize);
 269                         break;
 270                 case 'd':
 271                         cmd = CMD_CPU_DISABLE;
 272                         cpu_parse(argv[optind - 1], cpu_set, setsize);
 273                         break;
 274                 case 'e':
 275                         cmd = CMD_CPU_ENABLE;
 276                         cpu_parse(argv[optind - 1], cpu_set, setsize);
 277                         break;
 278                 case 'g':
 279                         cmd = CMD_CPU_DECONFIGURE;
 280                         cpu_parse(argv[optind - 1], cpu_set, setsize);
 281                         break;
 282                 case 'h':
 283                         usage(stdout);
 284                 case 'p':
 285                         if (strcmp("horizontal", argv[optind - 1]) == 0)
 286                                 cmd = CMD_CPU_DISPATCH_HORIZONTAL;
 287                         else if (strcmp("vertical", argv[optind - 1]) == 0)
 288                                 cmd = CMD_CPU_DISPATCH_VERTICAL;
 289                         else
 290                                 errx(EXIT_FAILURE, _("unsupported argument: %s"),
 291                                      argv[optind -1 ]);
 292                         break;
 293                 case 'r':
 294                         cmd = CMD_CPU_RESCAN;
 295                         break;
 296                 case 'V':
 297                         printf(_("%s from %s\n"), program_invocation_short_name,
 298                                PACKAGE_STRING);
 299                         return EXIT_SUCCESS;
 300                 default:
 301                         usage(stderr);
 302                 }
 303         }
 304
 305         if ((argc == 1) || (argc != optind))
 306                 usage(stderr);
 307
 308         switch (cmd) {
 309         case CMD_CPU_ENABLE:
 310                 return cpu_enable(cpu_set, maxcpus, 1);
 311         case CMD_CPU_DISABLE:
 312                 return cpu_enable(cpu_set, maxcpus, 0);
 313         case CMD_CPU_CONFIGURE:
 314                 return cpu_configure(cpu_set, maxcpus, 1);
 315         case CMD_CPU_DECONFIGURE:
 316                 return cpu_configure(cpu_set, maxcpus, 0);
 317         case CMD_CPU_RESCAN:
 318                 return cpu_rescan();
 319         case CMD_CPU_DISPATCH_HORIZONTAL:
 320                 return cpu_set_dispatch(0);
 321         case CMD_CPU_DISPATCH_VERTICAL:
 322                 return cpu_set_dispatch(1);
 323         }
 324         return EXIT_SUCCESS;
 325 }