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-rw-r--r--sys-utils/chcpu.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/sys-utils/chcpu.c b/sys-utils/chcpu.c
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index 0000000..36c47af
--- /dev/null
+++ b/sys-utils/chcpu.c
@@ -0,0 +1,389 @@
+/*
+ * chcpu - CPU configuration tool
+ *
+ * Copyright IBM Corp. 2011
+ * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <ctype.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/utsname.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "cpuset.h"
+#include "nls.h"
+#include "xalloc.h"
+#include "c.h"
+#include "strutils.h"
+#include "bitops.h"
+#include "path.h"
+#include "closestream.h"
+#include "optutils.h"
+
+#define EXCL_ERROR "--{configure,deconfigure,disable,dispatch,enable}"
+
+/* partial success, otherwise we return regular EXIT_{SUCCESS,FAILURE} */
+#define CHCPU_EXIT_SOMEOK 64
+
+#define _PATH_SYS_CPU "/sys/devices/system/cpu"
+
+static cpu_set_t *onlinecpus;
+static int maxcpus;
+
+#define is_cpu_online(cpu) (CPU_ISSET_S((cpu), CPU_ALLOC_SIZE(maxcpus), onlinecpus))
+#define num_online_cpus() (CPU_COUNT_S(CPU_ALLOC_SIZE(maxcpus), onlinecpus))
+
+enum {
+ CMD_CPU_ENABLE = 0,
+ CMD_CPU_DISABLE,
+ CMD_CPU_CONFIGURE,
+ CMD_CPU_DECONFIGURE,
+ CMD_CPU_RESCAN,
+ CMD_CPU_DISPATCH_HORIZONTAL,
+ CMD_CPU_DISPATCH_VERTICAL,
+};
+
+/* returns: 0 = success
+ * < 0 = failure
+ * > 0 = partial success
+ */
+static int cpu_enable(struct path_cxt *sys, cpu_set_t *cpu_set, size_t setsize, int enable)
+{
+ int cpu;
+ int online, rc;
+ int configured = -1;
+ int fails = 0;
+
+ for (cpu = 0; cpu < maxcpus; cpu++) {
+ if (!CPU_ISSET_S(cpu, setsize, cpu_set))
+ continue;
+ if (ul_path_accessf(sys, F_OK, "cpu%d", cpu) != 0) {
+ warnx(_("CPU %u does not exist"), cpu);
+ fails++;
+ continue;
+ }
+ if (ul_path_accessf(sys, F_OK, "cpu%d/online", cpu) != 0) {
+ warnx(_("CPU %u is not hot pluggable"), cpu);
+ fails++;
+ continue;
+ }
+ if (ul_path_readf_s32(sys, &online, "cpu%d/online", cpu) == 0
+ && online == 1
+ && enable == 1) {
+ printf(_("CPU %u is already enabled\n"), cpu);
+ continue;
+ }
+ if (online == 0 && enable == 0) {
+ printf(_("CPU %u is already disabled\n"), cpu);
+ continue;
+ }
+ if (ul_path_accessf(sys, F_OK, "cpu%d/configure", cpu) == 0)
+ ul_path_readf_s32(sys, &configured, "cpu%d/configure", cpu);
+ if (enable) {
+ rc = ul_path_writef_string(sys, "1", "cpu%d/online", cpu);
+ if (rc != 0 && configured == 0) {
+ warn(_("CPU %u enable failed (CPU is deconfigured)"), cpu);
+ fails++;
+ } else if (rc != 0) {
+ warn(_("CPU %u enable failed"), cpu);
+ fails++;
+ } else
+ printf(_("CPU %u enabled\n"), cpu);
+ } else {
+ if (onlinecpus && num_online_cpus() == 1) {
+ warnx(_("CPU %u disable failed (last enabled CPU)"), cpu);
+ fails++;
+ continue;
+ }
+ rc = ul_path_writef_string(sys, "0", "cpu%d/online", cpu);
+ if (rc != 0) {
+ warn(_("CPU %u disable failed"), cpu);
+ fails++;
+ } else {
+ printf(_("CPU %u disabled\n"), cpu);
+ if (onlinecpus)
+ CPU_CLR_S(cpu, setsize, onlinecpus);
+ }
+ }
+ }
+
+ return fails == 0 ? 0 : fails == maxcpus ? -1 : 1;
+}
+
+static int cpu_rescan(struct path_cxt *sys)
+{
+ if (ul_path_access(sys, F_OK, "rescan") != 0)
+ errx(EXIT_FAILURE, _("This system does not support rescanning of CPUs"));
+
+ if (ul_path_write_string(sys, "1", "rescan") != 0)
+ err(EXIT_FAILURE, _("Failed to trigger rescan of CPUs"));
+
+ printf(_("Triggered rescan of CPUs\n"));
+ return 0;
+}
+
+static int cpu_set_dispatch(struct path_cxt *sys, int mode)
+{
+ if (ul_path_access(sys, F_OK, "dispatching") != 0)
+ errx(EXIT_FAILURE, _("This system does not support setting "
+ "the dispatching mode of CPUs"));
+ if (mode == 0) {
+ if (ul_path_write_string(sys, "0", "dispatching") != 0)
+ err(EXIT_FAILURE, _("Failed to set horizontal dispatch mode"));
+
+ printf(_("Successfully set horizontal dispatching mode\n"));
+ } else {
+ if (ul_path_write_string(sys, "1", "dispatching") != 0)
+ err(EXIT_FAILURE, _("Failed to set vertical dispatch mode"));
+
+ printf(_("Successfully set vertical dispatching mode\n"));
+ }
+ return 0;
+}
+
+/* returns: 0 = success
+ * < 0 = failure
+ * > 0 = partial success
+ */
+static int cpu_configure(struct path_cxt *sys, cpu_set_t *cpu_set, size_t setsize, int configure)
+{
+ int cpu;
+ int rc, current;
+ int fails = 0;
+
+ for (cpu = 0; cpu < maxcpus; cpu++) {
+ if (!CPU_ISSET_S(cpu, setsize, cpu_set))
+ continue;
+ if (ul_path_accessf(sys, F_OK, "cpu%d", cpu) != 0) {
+ warnx(_("CPU %u does not exist"), cpu);
+ fails++;
+ continue;
+ }
+ if (ul_path_accessf(sys, F_OK, "cpu%d/configure", cpu) != 0) {
+ warnx(_("CPU %u is not configurable"), cpu);
+ fails++;
+ continue;
+ }
+ ul_path_readf_s32(sys, &current, "cpu%d/configure", cpu);
+ if (current == 1 && configure == 1) {
+ printf(_("CPU %u is already configured\n"), cpu);
+ continue;
+ }
+ if (current == 0 && configure == 0) {
+ printf(_("CPU %u is already deconfigured\n"), cpu);
+ continue;
+ }
+ if (current == 1 && configure == 0 && onlinecpus &&
+ is_cpu_online(cpu)) {
+ warnx(_("CPU %u deconfigure failed (CPU is enabled)"), cpu);
+ fails++;
+ continue;
+ }
+ if (configure) {
+ rc = ul_path_writef_string(sys, "1", "cpu%d/configure", cpu);
+ if (rc != 0) {
+ warn(_("CPU %u configure failed"), cpu);
+ fails++;
+ } else
+ printf(_("CPU %u configured\n"), cpu);
+ } else {
+ rc = ul_path_writef_string(sys, "0", "cpu%d/configure", cpu);
+ if (rc != 0) {
+ warn(_("CPU %u deconfigure failed"), cpu);
+ fails++;
+ } else
+ printf(_("CPU %u deconfigured\n"), cpu);
+ }
+ }
+
+ return fails == 0 ? 0 : fails == maxcpus ? -1 : 1;
+}
+
+static void cpu_parse(char *cpu_string, cpu_set_t *cpu_set, size_t setsize)
+{
+ int rc;
+
+ rc = cpulist_parse(cpu_string, cpu_set, setsize, 1);
+ if (rc == 0)
+ return;
+ if (rc == 2)
+ errx(EXIT_FAILURE, _("invalid CPU number in CPU list: %s"), cpu_string);
+ errx(EXIT_FAILURE, _("failed to parse CPU list: %s"), cpu_string);
+}
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ fprintf(out, _(
+ "\nUsage:\n"
+ " %s [options]\n"), program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("Configure CPUs in a multi-processor system.\n"), out);
+
+ fputs(USAGE_OPTIONS, stdout);
+ fputs(_(
+ " -e, --enable <cpu-list> enable cpus\n"
+ " -d, --disable <cpu-list> disable cpus\n"
+ " -c, --configure <cpu-list> configure cpus\n"
+ " -g, --deconfigure <cpu-list> deconfigure cpus\n"
+ " -p, --dispatch <mode> set dispatching mode\n"
+ " -r, --rescan trigger rescan of cpus\n"
+ ), stdout);
+ printf(USAGE_HELP_OPTIONS(31));
+
+ printf(USAGE_MAN_TAIL("chcpu(8)"));
+ exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char *argv[])
+{
+ struct path_cxt *sys = NULL; /* _PATH_SYS_CPU handler */
+ cpu_set_t *cpu_set;
+ size_t setsize;
+ int cmd = -1;
+ int c, rc;
+
+ static const struct option longopts[] = {
+ { "configure", required_argument, NULL, 'c' },
+ { "deconfigure",required_argument, NULL, 'g' },
+ { "disable", required_argument, NULL, 'd' },
+ { "dispatch", required_argument, NULL, 'p' },
+ { "enable", required_argument, NULL, 'e' },
+ { "help", no_argument, NULL, 'h' },
+ { "rescan", no_argument, NULL, 'r' },
+ { "version", no_argument, NULL, 'V' },
+ { NULL, 0, NULL, 0 }
+ };
+
+ static const ul_excl_t excl[] = { /* rows and cols in ASCII order */
+ { 'c','d','e','g','p' },
+ { 0 }
+ };
+ int excl_st[ARRAY_SIZE(excl)] = UL_EXCL_STATUS_INIT;
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ ul_path_init_debug();
+ sys = ul_new_path(_PATH_SYS_CPU);
+ if (!sys)
+ err(EXIT_FAILURE, _("failed to initialize sysfs handler"));
+
+ maxcpus = get_max_number_of_cpus();
+ if (maxcpus < 1)
+ errx(EXIT_FAILURE, _("cannot determine NR_CPUS; aborting"));
+
+ if (ul_path_access(sys, F_OK, "online") == 0)
+ ul_path_readf_cpulist(sys, &cpu_set, maxcpus, "online");
+
+ setsize = CPU_ALLOC_SIZE(maxcpus);
+ cpu_set = CPU_ALLOC(maxcpus);
+ if (!cpu_set)
+ err(EXIT_FAILURE, _("cpuset_alloc failed"));
+
+ while ((c = getopt_long(argc, argv, "c:d:e:g:hp:rV", longopts, NULL)) != -1) {
+
+ err_exclusive_options(c, longopts, excl, excl_st);
+
+ switch (c) {
+ case 'c':
+ cmd = CMD_CPU_CONFIGURE;
+ cpu_parse(argv[optind - 1], cpu_set, setsize);
+ break;
+ case 'd':
+ cmd = CMD_CPU_DISABLE;
+ cpu_parse(argv[optind - 1], cpu_set, setsize);
+ break;
+ case 'e':
+ cmd = CMD_CPU_ENABLE;
+ cpu_parse(argv[optind - 1], cpu_set, setsize);
+ break;
+ case 'g':
+ cmd = CMD_CPU_DECONFIGURE;
+ cpu_parse(argv[optind - 1], cpu_set, setsize);
+ break;
+ case 'h':
+ usage();
+ case 'p':
+ if (strcmp("horizontal", argv[optind - 1]) == 0)
+ cmd = CMD_CPU_DISPATCH_HORIZONTAL;
+ else if (strcmp("vertical", argv[optind - 1]) == 0)
+ cmd = CMD_CPU_DISPATCH_VERTICAL;
+ else
+ errx(EXIT_FAILURE, _("unsupported argument: %s"),
+ argv[optind -1 ]);
+ break;
+ case 'r':
+ cmd = CMD_CPU_RESCAN;
+ break;
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ return EXIT_SUCCESS;
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ if ((argc == 1) || (argc != optind)) {
+ warnx(_("bad usage"));
+ errtryhelp(EXIT_FAILURE);
+ }
+
+ switch (cmd) {
+ case CMD_CPU_ENABLE:
+ rc = cpu_enable(sys, cpu_set, maxcpus, 1);
+ break;
+ case CMD_CPU_DISABLE:
+ rc = cpu_enable(sys, cpu_set, maxcpus, 0);
+ break;
+ case CMD_CPU_CONFIGURE:
+ rc = cpu_configure(sys, cpu_set, maxcpus, 1);
+ break;
+ case CMD_CPU_DECONFIGURE:
+ rc = cpu_configure(sys, cpu_set, maxcpus, 0);
+ break;
+ case CMD_CPU_RESCAN:
+ rc = cpu_rescan(sys);
+ break;
+ case CMD_CPU_DISPATCH_HORIZONTAL:
+ rc = cpu_set_dispatch(sys, 0);
+ break;
+ case CMD_CPU_DISPATCH_VERTICAL:
+ rc = cpu_set_dispatch(sys, 1);
+ break;
+ default:
+ rc = -EINVAL;
+ break;
+ }
+
+ ul_unref_path(sys);
+
+ return rc == 0 ? EXIT_SUCCESS :
+ rc < 0 ? EXIT_FAILURE : CHCPU_EXIT_SOMEOK;
+}
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