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/*
* (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 */
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 = sysfs_is_cpu_online(cpu);
if(sysfs_topology_read_file(
cpu,
"physical_package_id",
&(cpu_top->core_info[cpu].pkg)) < 0)
return -1;
if(sysfs_topology_read_file(
cpu,
"core_id",
&(cpu_top->core_info[cpu].core)) < 0)
return -1;
}
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) {
last_pkg = cpu_top->core_info[cpu].pkg;
cpu_top->pkgs++;
}
}
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);
}
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