diff options
Diffstat (limited to 'tools/power/cpupower/utils/helpers/topology.c')
| -rw-r--r-- | tools/power/cpupower/utils/helpers/topology.c | 111 |
1 files changed, 111 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 00000000..4eae2c47 --- /dev/null +++ b/tools/power/cpupower/utils/helpers/topology.c @@ -0,0 +1,111 @@ +/* + * (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; + /* flags */ + unsigned int is_online:1; +}; + +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].cpu = cpu; + cpu_top->core_info[cpu].is_online = sysfs_is_cpu_online(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->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); +} |