2 * (C) 2010,2011 Thomas Renninger <trenn@suse.de>, Novell Inc.
4 * Licensed under the terms of the GNU GPL License version 2.
6 * ToDo: Needs to be done more properly for AMD/Intel specifics
9 /* Helper struct for qsort, must be in sync with cpupower_topology.cpu_info */
10 /* Be careful: Need to pass unsigned to the sort, so that offlined cores are
11 in the end, but double check for -1 for offlined cpus at other places */
19 #include <helpers/helpers.h>
20 #include <helpers/sysfs.h>
22 /* returns -1 on failure, 0 on success */
23 static int sysfs_topology_read_file(unsigned int cpu, const char *fname, int *result)
25 char linebuf[MAX_LINE_LEN];
27 char path[SYSFS_PATH_MAX];
29 snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/topology/%s",
31 if (sysfs_read_file(path, linebuf, MAX_LINE_LEN) == 0)
33 *result = strtol(linebuf, &endp, 0);
34 if (endp == linebuf || errno == ERANGE)
39 static int __compare(const void *t1, const void *t2)
41 struct cpuid_core_info *top1 = (struct cpuid_core_info *)t1;
42 struct cpuid_core_info *top2 = (struct cpuid_core_info *)t2;
43 if (top1->pkg < top2->pkg)
45 else if (top1->pkg > top2->pkg)
47 else if (top1->core < top2->core)
49 else if (top1->core > top2->core)
51 else if (top1->cpu < top2->cpu)
53 else if (top1->cpu > top2->cpu)
60 * Returns amount of cpus, negative on error, cpu_top must be
61 * passed to cpu_topology_release to free resources
63 * Array is sorted after ->pkg, ->core, then ->cpu
65 int get_cpu_topology(struct cpupower_topology *cpu_top)
67 int cpu, last_pkg, cpus = sysconf(_SC_NPROCESSORS_CONF);
69 cpu_top->core_info = malloc(sizeof(struct cpuid_core_info) * cpus);
70 if (cpu_top->core_info == NULL)
72 cpu_top->pkgs = cpu_top->cores = 0;
73 for (cpu = 0; cpu < cpus; cpu++) {
74 cpu_top->core_info[cpu].cpu = cpu;
75 cpu_top->core_info[cpu].is_online = sysfs_is_cpu_online(cpu);
76 if(sysfs_topology_read_file(
78 "physical_package_id",
79 &(cpu_top->core_info[cpu].pkg)) < 0) {
80 cpu_top->core_info[cpu].pkg = -1;
81 cpu_top->core_info[cpu].core = -1;
84 if(sysfs_topology_read_file(
87 &(cpu_top->core_info[cpu].core)) < 0) {
88 cpu_top->core_info[cpu].pkg = -1;
89 cpu_top->core_info[cpu].core = -1;
94 qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info),
97 /* Count the number of distinct pkgs values. This works
98 because the primary sort of the core_info struct was just
100 last_pkg = cpu_top->core_info[0].pkg;
101 for(cpu = 1; cpu < cpus; cpu++) {
102 if (cpu_top->core_info[cpu].pkg != last_pkg &&
103 cpu_top->core_info[cpu].pkg != -1) {
105 last_pkg = cpu_top->core_info[cpu].pkg;
109 if (!cpu_top->core_info[0].pkg == -1)
112 /* Intel's cores count is not consecutively numbered, there may
113 * be a core_id of 3, but none of 2. Assume there always is 0
114 * Get amount of cores by counting duplicates in a package
115 for (cpu = 0; cpu_top->core_info[cpu].pkg = 0 && cpu < cpus; cpu++) {
116 if (cpu_top->core_info[cpu].core == 0)
122 void cpu_topology_release(struct cpupower_topology cpu_top)
124 free(cpu_top.core_info);