Linux-libre 4.7.1-gnupck-4.7.1-gnu

1 files changed, 192 insertions, 0 deletions

diff --git a/tools/power/cpupower/lib/cpupower.c b/tools/power/cpupower/lib/cpupower.c
new file mode 100644
index 000000000..9c395ec92
--- /dev/null
+++ b/tools/power/cpupower/lib/cpupower.c
@@ -0,0 +1,192 @@
+/*
+ *  (C) 2004-2009  Dominik Brodowski <linux@dominikbrodowski.de>
+ *
+ *  Licensed under the terms of the GNU GPL License version 2.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "cpupower.h"
+#include "cpupower_intern.h"
+
+unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen)
+{
+	int fd;
+	ssize_t numread;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return 0;
+
+	numread = read(fd, buf, buflen - 1);
+	if (numread < 1) {
+		close(fd);
+		return 0;
+	}
+
+	buf[numread] = '\0';
+	close(fd);
+
+	return (unsigned int) numread;
+}
+
+/*
+ * Detect whether a CPU is online
+ *
+ * Returns:
+ *     1 -> if CPU is online
+ *     0 -> if CPU is offline
+ *     negative errno values in error case
+ */
+int cpupower_is_cpu_online(unsigned int cpu)
+{
+	char path[SYSFS_PATH_MAX];
+	int fd;
+	ssize_t numread;
+	unsigned long long value;
+	char linebuf[MAX_LINE_LEN];
+	char *endp;
+	struct stat statbuf;
+
+	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u", cpu);
+
+	if (stat(path, &statbuf) != 0)
+		return 0;
+
+	/*
+	 * kernel without CONFIG_HOTPLUG_CPU
+	 * -> cpuX directory exists, but not cpuX/online file
+	 */
+	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/online", cpu);
+	if (stat(path, &statbuf) != 0)
+		return 1;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -errno;
+
+	numread = read(fd, linebuf, MAX_LINE_LEN - 1);
+	if (numread < 1) {
+		close(fd);
+		return -EIO;
+	}
+	linebuf[numread] = '\0';
+	close(fd);
+
+	value = strtoull(linebuf, &endp, 0);
+	if (value > 1)
+		return -EINVAL;
+
+	return value;
+}
+
+/* returns -1 on failure, 0 on success */
+static int sysfs_topology_read_file(unsigned int cpu, const char *fname, int *result)
+{
+	char linebuf[MAX_LINE_LEN];
+	char *endp;
+	char path[SYSFS_PATH_MAX];
+
+	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/topology/%s",
+			 cpu, fname);
+	if (sysfs_read_file(path, linebuf, MAX_LINE_LEN) == 0)
+		return -1;
+	*result = strtol(linebuf, &endp, 0);
+	if (endp == linebuf || errno == ERANGE)
+		return -1;
+	return 0;
+}
+
+static int __compare(const void *t1, const void *t2)
+{
+	struct cpuid_core_info *top1 = (struct cpuid_core_info *)t1;
+	struct cpuid_core_info *top2 = (struct cpuid_core_info *)t2;
+	if (top1->pkg < top2->pkg)
+		return -1;
+	else if (top1->pkg > top2->pkg)
+		return 1;
+	else if (top1->core < top2->core)
+		return -1;
+	else if (top1->core > top2->core)
+		return 1;
+	else if (top1->cpu < top2->cpu)
+		return -1;
+	else if (top1->cpu > top2->cpu)
+		return 1;
+	else
+		return 0;
+}
+
+/*
+ * Returns amount of cpus, negative on error, cpu_top must be
+ * passed to cpu_topology_release to free resources
+ *
+ * Array is sorted after ->pkg, ->core, then ->cpu
+ */
+int get_cpu_topology(struct cpupower_topology *cpu_top)
+{
+	int cpu, last_pkg, cpus = sysconf(_SC_NPROCESSORS_CONF);
+
+	cpu_top->core_info = malloc(sizeof(struct cpuid_core_info) * cpus);
+	if (cpu_top->core_info == NULL)
+		return -ENOMEM;
+	cpu_top->pkgs = cpu_top->cores = 0;
+	for (cpu = 0; cpu < cpus; cpu++) {
+		cpu_top->core_info[cpu].cpu = cpu;
+		cpu_top->core_info[cpu].is_online = cpupower_is_cpu_online(cpu);
+		if(sysfs_topology_read_file(
+			cpu,
+			"physical_package_id",
+			&(cpu_top->core_info[cpu].pkg)) < 0) {
+			cpu_top->core_info[cpu].pkg = -1;
+			cpu_top->core_info[cpu].core = -1;
+			continue;
+		}
+		if(sysfs_topology_read_file(
+			cpu,
+			"core_id",
+			&(cpu_top->core_info[cpu].core)) < 0) {
+			cpu_top->core_info[cpu].pkg = -1;
+			cpu_top->core_info[cpu].core = -1;
+			continue;
+		}
+	}
+
+	qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info),
+	      __compare);
+
+	/* Count the number of distinct pkgs values. This works
+	   because the primary sort of the core_info struct was just
+	   done by pkg value. */
+	last_pkg = cpu_top->core_info[0].pkg;
+	for(cpu = 1; cpu < cpus; cpu++) {
+		if (cpu_top->core_info[cpu].pkg != last_pkg &&
+				cpu_top->core_info[cpu].pkg != -1) {
+
+			last_pkg = cpu_top->core_info[cpu].pkg;
+			cpu_top->pkgs++;
+		}
+	}
+	if (!(cpu_top->core_info[0].pkg == -1))
+		cpu_top->pkgs++;
+
+	/* Intel's cores count is not consecutively numbered, there may
+	 * be a core_id of 3, but none of 2. Assume there always is 0
+	 * Get amount of cores by counting duplicates in a package
+	for (cpu = 0; cpu_top->core_info[cpu].pkg = 0 && cpu < cpus; cpu++) {
+		if (cpu_top->core_info[cpu].core == 0)
+	cpu_top->cores++;
+	*/
+	return cpus;
+}
+
+void cpu_topology_release(struct cpupower_topology cpu_top)
+{
+	free(cpu_top.core_info);
+}