system_cmds/cpuctl.tproj/cpuctl.c

   1 //
   2 //  cpuctl.c
   3 //  system_cmds
   4 //
   5 //  Copyright (c) 2019 Apple Inc. All rights reserved.
   6 //
   7
   8 #include <err.h>
   9 #include <getopt.h>
  10 #include <limits.h>
  11 #include <stdbool.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15 #include <sysexits.h>
  16 #include <unistd.h>
  17 #include <mach/mach.h>
  18
  19 static void usage()
  20 {
  21     printf("usage: cpuctl [ list ]\n");
  22     printf("       cpuctl { offline | online } <cpu> [ <cpu>... ]\n");
  23     exit(EX_USAGE);
  24 }
  25
  26 static void fetch_cpu_info(host_t *priv_port,
  27                            processor_port_array_t proc_ports,
  28                            mach_msg_type_number_t proc_count,
  29                            processor_basic_info_data_t *cpus)
  30 {
  31     for (int i = 0; i < proc_count; i++) {
  32         mach_msg_type_number_t info_count = PROCESSOR_BASIC_INFO_COUNT;
  33
  34         if (processor_info(proc_ports[i], PROCESSOR_BASIC_INFO, priv_port,
  35                            (processor_info_t)&cpus[i], &info_count) != KERN_SUCCESS) {
  36             errx(EX_OSERR, "processor_info(%d) failed", i);
  37         }
  38     }
  39 }
  40
  41 static int do_cmd_list(mach_msg_type_number_t proc_count, processor_basic_info_data_t *cpus)
  42 {
  43     int prev_lowest = -1;
  44     for (int i = 0; i < proc_count; i++) {
  45         int lowest_slot = INT_MAX;
  46         int lowest_idx = -1;
  47         for (int j = 0; j < proc_count; j++) {
  48             int slot = cpus[j].slot_num;
  49             if (slot > prev_lowest && slot < lowest_slot) {
  50                 lowest_slot = slot;
  51                 lowest_idx = j;
  52             }
  53         }
  54         if (lowest_idx == -1)
  55             errx(EX_OSERR, "slot numbers are out of range");
  56
  57         processor_basic_info_data_t *cpu = &cpus[lowest_idx];
  58         printf("CPU%d: %-7s type=%x,%x master=%d\n",
  59                cpu->slot_num,
  60                cpu->running ? "online" : "offline",
  61                cpu->cpu_type,
  62                cpu->cpu_subtype,
  63                cpu->is_master);
  64
  65         prev_lowest = lowest_slot;
  66     }
  67     return 0;
  68 }
  69
  70 static int find_cpu_by_slot(mach_msg_type_number_t proc_count,
  71                             processor_basic_info_data_t *cpus,
  72                             int slot)
  73 {
  74     for (int i = 0; i < proc_count; i++) {
  75         if (cpus[i].slot_num == slot)
  76             return i;
  77     }
  78     return -1;
  79 }
  80
  81 int main(int argc, char **argv)
  82 {
  83     int opt;
  84
  85     while ((opt = getopt(argc, argv, "h")) != -1) {
  86         switch (opt) {
  87             case 'h':
  88                 usage();
  89         }
  90     }
  91
  92     host_t priv_port;
  93     if (host_get_host_priv_port(mach_host_self(), &priv_port) != KERN_SUCCESS)
  94         errx(EX_OSERR, "host_get_host_priv_port() failed");
  95
  96     processor_port_array_t proc_ports;
  97     mach_msg_type_number_t proc_count;
  98     if (host_processors(priv_port, &proc_ports, &proc_count) != KERN_SUCCESS)
  99         errx(EX_OSERR, "host_processors() failed");
 100
 101     processor_basic_info_data_t *cpus = calloc(proc_count, sizeof(*cpus));
 102     if (!cpus)
 103         errx(EX_OSERR, "calloc() failed");
 104     fetch_cpu_info(&priv_port, proc_ports, proc_count, cpus);
 105
 106     if (optind == argc)
 107         return do_cmd_list(proc_count, cpus);
 108
 109     const char *cmd = argv[optind];
 110     optind++;
 111
 112     if (!strcmp(cmd, "list"))
 113         return do_cmd_list(proc_count, cpus);
 114
 115     bool up = true;
 116     if (!strncmp(cmd, "off", 3))
 117         up = false;
 118     else if (strncmp(cmd, "on", 2))
 119         usage();
 120
 121     if (optind == argc)
 122         usage();
 123
 124     int ret = 0;
 125     for (; optind < argc; optind++) {
 126         char *endp = NULL;
 127         int slot = (int)strtoul(argv[optind], &endp, 0);
 128         if (*endp != 0)
 129             usage();
 130
 131         int cpu = find_cpu_by_slot(proc_count, cpus, slot);
 132         if (cpu == -1)
 133             errx(EX_USAGE, "Invalid CPU ID %d", slot);
 134
 135         if (up) {
 136             if (processor_start(proc_ports[cpu]) != KERN_SUCCESS)
 137                 errx(EX_OSERR, "processor_start(%u) failed", cpu);
 138         } else {
 139             if (processor_exit(proc_ports[cpu]) != KERN_SUCCESS)
 140                 errx(EX_OSERR, "processor_exit(%u) failed", cpu);
 141         }
 142     }
 143
 144     return ret;
 145 }