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Diffstat (limited to 'tools/power/cpupower/bench/system.c')
| -rw-r--r-- | tools/power/cpupower/bench/system.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/tools/power/cpupower/bench/system.c b/tools/power/cpupower/bench/system.c new file mode 100644 index 00000000000..3e3a82e8bdd --- /dev/null +++ b/tools/power/cpupower/bench/system.c @@ -0,0 +1,188 @@ +/* cpufreq-bench CPUFreq microbenchmark + * + * Copyright (C) 2008 Christian Kornacker <ckornacker@suse.de> + * + * 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 will 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <stdio.h> +#include <time.h> +#include <sys/time.h> +#include <sys/types.h> +#include <unistd.h> + +#include <sched.h> + +#include <cpufreq.h> + +#include "config.h" +#include "system.h" + +/** + * returns time since epoch in µs + * + * @retval time + **/ + +long long int get_time() +{ + struct timeval now; + + gettimeofday(&now, NULL); + + return (long long int)(now.tv_sec * 1000000LL + now.tv_usec); +} + +/** + * sets the cpufreq governor + * + * @param governor cpufreq governor name + * @param cpu cpu for which the governor should be set + * + * @retval 0 on success + * @retval -1 when failed + **/ + +int set_cpufreq_governor(char *governor, unsigned int cpu) +{ + + dprintf("set %s as cpufreq governor\n", governor); + + if (cpufreq_cpu_exists(cpu) != 0) { + perror("cpufreq_cpu_exists"); + fprintf(stderr, "error: cpu %u does not exist\n", cpu); + return -1; + } + + if (cpufreq_modify_policy_governor(cpu, governor) != 0) { + perror("cpufreq_modify_policy_governor"); + fprintf(stderr, "error: unable to set %s governor\n", governor); + return -1; + } + + return 0; +} + +/** + * sets cpu affinity for the process + * + * @param cpu cpu# to which the affinity should be set + * + * @retval 0 on success + * @retval -1 when setting the affinity failed + **/ + +int set_cpu_affinity(unsigned int cpu) +{ + cpu_set_t cpuset; + + CPU_ZERO(&cpuset); + CPU_SET(cpu, &cpuset); + + dprintf("set affinity to cpu #%u\n", cpu); + + if (sched_setaffinity(getpid(), sizeof(cpu_set_t), &cpuset) < 0) { + perror("sched_setaffinity"); + fprintf(stderr, "warning: unable to set cpu affinity\n"); + return -1; + } + + return 0; +} + +/** + * sets the process priority parameter + * + * @param priority priority value + * + * @retval 0 on success + * @retval -1 when setting the priority failed + **/ + +int set_process_priority(int priority) +{ + struct sched_param param; + + dprintf("set scheduler priority to %i\n", priority); + + param.sched_priority = priority; + + if (sched_setscheduler(0, SCHEDULER, ¶m) < 0) { + perror("sched_setscheduler"); + fprintf(stderr, "warning: unable to set scheduler priority\n"); + return -1; + } + + return 0; +} + +/** + * notifys the user that the benchmark may run some time + * + * @param config benchmark config values + * + **/ + +void prepare_user(const struct config *config) +{ + unsigned long sleep_time = 0; + unsigned long load_time = 0; + unsigned int round; + + for (round = 0; round < config->rounds; round++) { + sleep_time += 2 * config->cycles * (config->sleep + config->sleep_step * round); + load_time += 2 * config->cycles * (config->load + config->load_step * round) + (config->load + config->load_step * round * 4); + } + + if (config->verbose || config->output != stdout) + printf("approx. test duration: %im\n", + (int)((sleep_time + load_time) / 60000000)); +} + +/** + * sets up the cpu affinity and scheduler priority + * + * @param config benchmark config values + * + **/ + +void prepare_system(const struct config *config) +{ + if (config->verbose) + printf("set cpu affinity to cpu #%u\n", config->cpu); + + set_cpu_affinity(config->cpu); + + switch (config->prio) { + case SCHED_HIGH: + if (config->verbose) + printf("high priority condition requested\n"); + + set_process_priority(PRIORITY_HIGH); + break; + case SCHED_LOW: + if (config->verbose) + printf("low priority condition requested\n"); + + set_process_priority(PRIORITY_LOW); + break; + default: + if (config->verbose) + printf("default priority condition requested\n"); + + set_process_priority(PRIORITY_DEFAULT); + } +} + |