1 /* 2 * (C) 2010,2011 Thomas Renninger <trenn@suse.de>, Novell Inc. 3 * 4 * Licensed under the terms of the GNU GPL License version 2. 5 * 6 * ToDo: Needs to be done more properly for AMD/Intel specifics 7 */ 8 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 */ 12 13 #include <stdlib.h> 14 #include <stdio.h> 15 #include <unistd.h> 16 #include <errno.h> 17 #include <fcntl.h> 18 19 #include <helpers/helpers.h> 20 #include <helpers/sysfs.h> 21 22 /* returns -1 on failure, 0 on success */ 23 static int sysfs_topology_read_file(unsigned int cpu, const char *fname, int *result) 24 { 25 char linebuf[MAX_LINE_LEN]; 26 char *endp; 27 char path[SYSFS_PATH_MAX]; 28 29 snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/topology/%s", 30 cpu, fname); 31 if (sysfs_read_file(path, linebuf, MAX_LINE_LEN) == 0) 32 return -1; 33 *result = strtol(linebuf, &endp, 0); 34 if (endp == linebuf || errno == ERANGE) 35 return -1; 36 return 0; 37 } 38 39 static int __compare(const void *t1, const void *t2) 40 { 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) 44 return -1; 45 else if (top1->pkg > top2->pkg) 46 return 1; 47 else if (top1->core < top2->core) 48 return -1; 49 else if (top1->core > top2->core) 50 return 1; 51 else if (top1->cpu < top2->cpu) 52 return -1; 53 else if (top1->cpu > top2->cpu) 54 return 1; 55 else 56 return 0; 57 } 58 59 /* 60 * Returns amount of cpus, negative on error, cpu_top must be 61 * passed to cpu_topology_release to free resources 62 * 63 * Array is sorted after ->pkg, ->core, then ->cpu 64 */ 65 int get_cpu_topology(struct cpupower_topology *cpu_top) 66 { 67 int cpu, last_pkg, cpus = sysconf(_SC_NPROCESSORS_CONF); 68 69 cpu_top->core_info = malloc(sizeof(struct cpuid_core_info) * cpus); 70 if (cpu_top->core_info == NULL) 71 return -ENOMEM; 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( 77 cpu, 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; 82 continue; 83 } 84 if(sysfs_topology_read_file( 85 cpu, 86 "core_id", 87 &(cpu_top->core_info[cpu].core)) < 0) { 88 cpu_top->core_info[cpu].pkg = -1; 89 cpu_top->core_info[cpu].core = -1; 90 continue; 91 } 92 } 93 94 qsort(cpu_top->core_info, cpus, sizeof(struct cpuid_core_info), 95 __compare); 96 97 /* Count the number of distinct pkgs values. This works 98 because the primary sort of the core_info struct was just 99 done by pkg value. */ 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) { 104 105 last_pkg = cpu_top->core_info[cpu].pkg; 106 cpu_top->pkgs++; 107 } 108 } 109 if (!cpu_top->core_info[0].pkg == -1) 110 cpu_top->pkgs++; 111 112 /* 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) 117 cpu_top->cores++; 118 */ 119 return cpus; 120 } 121 122 void cpu_topology_release(struct cpupower_topology cpu_top) 123 { 124 free(cpu_top.core_info); 125 } 126