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authorDominik Brodowski <linux@dominikbrodowski.net>2011-03-30 18:30:11 +0400
committerDominik Brodowski <linux@dominikbrodowski.net>2011-07-29 20:35:36 +0400
commit7fe2f6399a84760a9af8896ac152728250f82adb (patch)
treefa4bf236359b8d6d9f8d6ff823ddd3e839da5768 /tools/power/cpupower/utils/cpufreq-set.c
parent02f8c6aee8df3cdc935e9bdd4f2d020306035dbe (diff)
downloadlinux-7fe2f6399a84760a9af8896ac152728250f82adb.tar.xz
cpupowerutils - cpufrequtils extended with quite some features
CPU power consumption vs performance tuning is no longer limited to CPU frequency switching anymore: deep sleep states, traditional dynamic frequency scaling and hidden turbo/boost frequencies are tied close together and depend on each other. The first two exist on different architectures like PPC, Itanium and ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will only run most efficiently if CPU and GPU has proper power management in place. Users and Developers want to have *one* tool to get an overview what their system supports and to monitor and debug CPU power management in detail. The tool should compile and work on as many architectures as possible. Once this tool stabilizes a bit, it is intended to replace the Intel-specific tools in tools/power/x86 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Diffstat (limited to 'tools/power/cpupower/utils/cpufreq-set.c')
-rw-r--r--tools/power/cpupower/utils/cpufreq-set.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/tools/power/cpupower/utils/cpufreq-set.c b/tools/power/cpupower/utils/cpufreq-set.c
new file mode 100644
index 000000000000..d415b6b52a09
--- /dev/null
+++ b/tools/power/cpupower/utils/cpufreq-set.c
@@ -0,0 +1,357 @@
+/*
+ * (C) 2004-2009 Dominik Brodowski <linux@dominikbrodowski.de>
+ *
+ * Licensed under the terms of the GNU GPL License version 2.
+ */
+
+
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <string.h>
+#include <ctype.h>
+
+#include <getopt.h>
+
+#include "cpufreq.h"
+#include "helpers/helpers.h"
+
+#define NORM_FREQ_LEN 32
+
+void freq_set_help(void)
+{
+ printf(_("Usage: cpupower frequency-set [options]\n"));
+ printf(_("Options:\n"));
+ printf(_(" -d FREQ, --min FREQ new minimum CPU frequency the governor may select\n"));
+ printf(_(" -u FREQ, --max FREQ new maximum CPU frequency the governor may select\n"));
+ printf(_(" -g GOV, --governor GOV new cpufreq governor\n"));
+ printf(_(" -f FREQ, --freq FREQ specific frequency to be set. Requires userspace\n"
+ " governor to be available and loaded\n"));
+ printf(_(" -r, --related Switches all hardware-related CPUs\n"));
+ printf(_(" -h, --help Prints out this screen\n"));
+ printf("\n");
+ printf(_("Notes:\n"
+ "1. Omitting the -c or --cpu argument is equivalent to setting it to \"all\"\n"));
+ printf(_("2. The -f FREQ, --freq FREQ parameter cannot be combined with any other parameter\n"
+ " except the -c CPU, --cpu CPU parameter\n"
+ "3. FREQuencies can be passed in Hz, kHz (default), MHz, GHz, or THz\n"
+ " by postfixing the value with the wanted unit name, without any space\n"
+ " (FREQuency in kHz =^ Hz * 0.001 =^ MHz * 1000 =^ GHz * 1000000).\n"));
+
+}
+
+static struct option set_opts[] = {
+ { .name="min", .has_arg=required_argument, .flag=NULL, .val='d'},
+ { .name="max", .has_arg=required_argument, .flag=NULL, .val='u'},
+ { .name="governor", .has_arg=required_argument, .flag=NULL, .val='g'},
+ { .name="freq", .has_arg=required_argument, .flag=NULL, .val='f'},
+ { .name="help", .has_arg=no_argument, .flag=NULL, .val='h'},
+ { .name="related", .has_arg=no_argument, .flag=NULL, .val='r'},
+ { },
+};
+
+static void print_error(void)
+{
+ printf(_("Error setting new values. Common errors:\n"
+ "- Do you have proper administration rights? (super-user?)\n"
+ "- Is the governor you requested available and modprobed?\n"
+ "- Trying to set an invalid policy?\n"
+ "- Trying to set a specific frequency, but userspace governor is not available,\n"
+ " for example because of hardware which cannot be set to a specific frequency\n"
+ " or because the userspace governor isn't loaded?\n"));
+};
+
+struct freq_units {
+ char* str_unit;
+ int power_of_ten;
+};
+
+const struct freq_units def_units[] = {
+ {"hz", -3},
+ {"khz", 0}, /* default */
+ {"mhz", 3},
+ {"ghz", 6},
+ {"thz", 9},
+ {NULL, 0}
+};
+
+static void print_unknown_arg(void)
+{
+ printf(_("invalid or unknown argument\n"));
+ freq_set_help();
+}
+
+static unsigned long string_to_frequency(const char *str)
+{
+ char normalized[NORM_FREQ_LEN];
+ const struct freq_units *unit;
+ const char *scan;
+ char *end;
+ unsigned long freq;
+ int power = 0, match_count = 0, i, cp, pad;
+
+ while (*str == '0')
+ str++;
+
+ for (scan = str; isdigit(*scan) || *scan == '.'; scan++) {
+ if (*scan == '.' && match_count == 0)
+ match_count = 1;
+ else if (*scan == '.' && match_count == 1)
+ return 0;
+ }
+
+ if (*scan) {
+ match_count = 0;
+ for (unit = def_units; unit->str_unit; unit++) {
+ for (i = 0;
+ scan[i] && tolower(scan[i]) == unit->str_unit[i];
+ ++i)
+ continue;
+ if (scan[i])
+ continue;
+ match_count++;
+ power = unit->power_of_ten;
+ }
+ if (match_count != 1)
+ return 0;
+ }
+
+ /* count the number of digits to be copied */
+ for (cp = 0; isdigit(str[cp]); cp++)
+ continue;
+
+ if (str[cp] == '.') {
+ while (power > -1 && isdigit(str[cp+1]))
+ cp++, power--;
+ }
+ if (power >= -1) /* not enough => pad */
+ pad = power + 1;
+ else /* to much => strip */
+ pad = 0, cp += power + 1;
+ /* check bounds */
+ if (cp <= 0 || cp + pad > NORM_FREQ_LEN - 1)
+ return 0;
+
+ /* copy digits */
+ for (i = 0; i < cp; i++, str++) {
+ if (*str == '.')
+ str++;
+ normalized[i] = *str;
+ }
+ /* and pad */
+ for (; i < cp + pad; i++)
+ normalized[i] = '0';
+
+ /* round up, down ? */
+ match_count = (normalized[i-1] >= '5');
+ /* and drop the decimal part */
+ normalized[i-1] = 0; /* cp > 0 && pad >= 0 ==> i > 0 */
+
+ /* final conversion (and applying rounding) */
+ errno = 0;
+ freq = strtoul(normalized, &end, 10);
+ if (errno)
+ return 0;
+ else {
+ if (match_count && freq != ULONG_MAX)
+ freq++;
+ return freq;
+ }
+}
+
+static int do_new_policy(unsigned int cpu, struct cpufreq_policy *new_pol)
+{
+ struct cpufreq_policy *cur_pol = cpufreq_get_policy(cpu);
+ int ret;
+
+ if (!cur_pol) {
+ printf(_("wrong, unknown or unhandled CPU?\n"));
+ return -EINVAL;
+ }
+
+ if (!new_pol->min)
+ new_pol->min = cur_pol->min;
+
+ if (!new_pol->max)
+ new_pol->max = cur_pol->max;
+
+ if (!new_pol->governor)
+ new_pol->governor = cur_pol->governor;
+
+ ret = cpufreq_set_policy(cpu, new_pol);
+
+ cpufreq_put_policy(cur_pol);
+
+ return ret;
+}
+
+
+static int do_one_cpu(unsigned int cpu, struct cpufreq_policy *new_pol,
+ unsigned long freq, unsigned int pc)
+{
+ switch (pc) {
+ case 0:
+ return cpufreq_set_frequency(cpu, freq);
+
+ case 1:
+ /* if only one value of a policy is to be changed, we can
+ * use a "fast path".
+ */
+ if (new_pol->min)
+ return cpufreq_modify_policy_min(cpu, new_pol->min);
+ else if (new_pol->max)
+ return cpufreq_modify_policy_max(cpu, new_pol->max);
+ else if (new_pol->governor)
+ return cpufreq_modify_policy_governor(cpu, new_pol->governor);
+
+ default:
+ /* slow path */
+ return do_new_policy(cpu, new_pol);
+ }
+}
+
+int cmd_freq_set(int argc, char **argv)
+{
+ extern char *optarg;
+ extern int optind, opterr, optopt;
+ int ret = 0, cont = 1;
+ int double_parm = 0, related = 0, policychange = 0;
+ unsigned long freq = 0;
+ char gov[20];
+ unsigned int cpu;
+
+ struct cpufreq_policy new_pol = {
+ .min = 0,
+ .max = 0,
+ .governor = NULL,
+ };
+
+ /* parameter parsing */
+ do {
+ ret = getopt_long(argc, argv, "d:u:g:f:hr", set_opts, NULL);
+ switch (ret) {
+ case '?':
+ print_unknown_arg();
+ return -EINVAL;
+ case 'h':
+ freq_set_help();
+ return 0;
+ case -1:
+ cont = 0;
+ break;
+ case 'r':
+ if (related)
+ double_parm++;
+ related++;
+ break;
+ case 'd':
+ if (new_pol.min)
+ double_parm++;
+ policychange++;
+ new_pol.min = string_to_frequency(optarg);
+ if (new_pol.min == 0) {
+ print_unknown_arg();
+ return -EINVAL;
+ }
+ break;
+ case 'u':
+ if (new_pol.max)
+ double_parm++;
+ policychange++;
+ new_pol.max = string_to_frequency(optarg);
+ if (new_pol.max == 0) {
+ print_unknown_arg();
+ return -EINVAL;
+ }
+ break;
+ case 'f':
+ if (freq)
+ double_parm++;
+ freq = string_to_frequency(optarg);
+ if (freq == 0) {
+ print_unknown_arg();
+ return -EINVAL;
+ }
+ break;
+ case 'g':
+ if (new_pol.governor)
+ double_parm++;
+ policychange++;
+ if ((strlen(optarg) < 3) || (strlen(optarg) > 18)) {
+ print_unknown_arg();
+ return -EINVAL;
+ }
+ if ((sscanf(optarg, "%s", gov)) != 1) {
+ print_unknown_arg();
+ return -EINVAL;
+ }
+ new_pol.governor = gov;
+ break;
+ }
+ } while(cont);
+
+ /* parameter checking */
+ if (double_parm) {
+ printf("the same parameter was passed more than once\n");
+ return -EINVAL;
+ }
+
+ if (freq && policychange) {
+ printf(_("the -f/--freq parameter cannot be combined with -d/--min, -u/--max or\n"
+ "-g/--governor parameters\n"));
+ return -EINVAL;
+ }
+
+ if (!freq && !policychange) {
+ printf(_("At least one parameter out of -f/--freq, -d/--min, -u/--max, and\n"
+ "-g/--governor must be passed\n"));
+ return -EINVAL;
+ }
+
+ /* Default is: set all CPUs */
+ if (bitmask_isallclear(cpus_chosen))
+ bitmask_setall(cpus_chosen);
+
+ /* Also set frequency settings for related CPUs if -r is passed */
+ if (related) {
+ for (cpu = bitmask_first(cpus_chosen);
+ cpu <= bitmask_last(cpus_chosen); cpu++) {
+ struct cpufreq_affected_cpus *cpus;
+
+ if (!bitmask_isbitset(cpus_chosen, cpu) ||
+ cpufreq_cpu_exists(cpu))
+ continue;
+
+ cpus = cpufreq_get_related_cpus(cpu);
+ if (!cpus)
+ break;
+ while (cpus->next) {
+ bitmask_setbit(cpus_chosen, cpus->cpu);
+ cpus = cpus->next;
+ }
+ cpufreq_put_related_cpus(cpus);
+ }
+ }
+
+
+ /* loop over CPUs */
+ for (cpu = bitmask_first(cpus_chosen);
+ cpu <= bitmask_last(cpus_chosen); cpu++) {
+
+ if (!bitmask_isbitset(cpus_chosen, cpu) ||
+ cpufreq_cpu_exists(cpu))
+ continue;
+
+ printf(_("Setting cpu: %d\n"), cpu);
+ ret = do_one_cpu(cpu, &new_pol, freq, policychange);
+ if (ret)
+ break;
+ }
+
+ if (ret)
+ print_error();
+
+ return ret;
+}