1 files changed, 108 insertions, 0 deletions

diff --git a/tools/power/cpupower/utils/helpers/topology.c b/tools/power/cpupower/utils/helpers/topology.c
new file mode 100644
index 000000000000..385ee5c7570c
--- /dev/null
+++ b/tools/power/cpupower/utils/helpers/topology.c
@@ -0,0 +1,108 @@
+/*
+ *  (C) 2010,2011       Thomas Renninger <trenn@suse.de>, Novell Inc.
+ *
+ *  Licensed under the terms of the GNU GPL License version 2.
+ *
+ * ToDo: Needs to be done more properly for AMD/Intel specifics
+ */
+
+/* Helper struct for qsort, must be in sync with cpupower_topology.cpu_info */
+/* Be careful: Need to pass unsigned to the sort, so that offlined cores are
+   in the end, but double check for -1 for offlined cpus at other places */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#include <helpers/helpers.h>
+#include <helpers/sysfs.h>
+
+/* returns -1 on failure, 0 on success */
+int sysfs_topology_read_file(unsigned int cpu, const char *fname)
+{
+        unsigned long value;
+        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;
+        value = strtoul(linebuf, &endp, 0);
+        if (endp == linebuf || errno == ERANGE)
+                return -1;
+        return value;
+}
+
+struct cpuid_core_info {
+        unsigned int pkg;
+        unsigned int thread;
+        unsigned int cpu;
+};
+
+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->thread < top2->thread)
+                return -1;
+        else if (top1->thread > top2->thread)
+                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, cpus = sysconf(_SC_NPROCESSORS_CONF);
+
+        cpu_top->core_info = malloc(sizeof(struct cpupower_topology) * 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].pkg =
+                        sysfs_topology_read_file(cpu, "physical_package_id");
+                if ((int)cpu_top->core_info[cpu].pkg != -1 &&
+                    cpu_top->core_info[cpu].pkg > cpu_top->pkgs)
+                        cpu_top->pkgs = cpu_top->core_info[cpu].pkg;
+                cpu_top->core_info[cpu].core =
+                        sysfs_topology_read_file(cpu, "core_id");
+                cpu_top->core_info[cpu].cpu = cpu;
+        }
+        cpu_top->pkgs++;
+
+        qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info),
+              __compare);
+
+        /* 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);
+}