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>

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 000000000000..3e3a82e8bdd9
--- /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, &param) < 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);
+	}
+}
+