in src/x86/mach/init.c [20:356]
void cpuinfo_x86_mach_init(void) {
struct cpuinfo_processor* processors = NULL;
struct cpuinfo_core* cores = NULL;
struct cpuinfo_cluster* clusters = NULL;
struct cpuinfo_package* packages = NULL;
struct cpuinfo_cache* l1i = NULL;
struct cpuinfo_cache* l1d = NULL;
struct cpuinfo_cache* l2 = NULL;
struct cpuinfo_cache* l3 = NULL;
struct cpuinfo_cache* l4 = NULL;
struct cpuinfo_mach_topology mach_topology = cpuinfo_mach_detect_topology();
processors = calloc(mach_topology.threads, sizeof(struct cpuinfo_processor));
if (processors == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" logical processors",
mach_topology.threads * sizeof(struct cpuinfo_processor), mach_topology.threads);
goto cleanup;
}
cores = calloc(mach_topology.cores, sizeof(struct cpuinfo_core));
if (cores == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" cores",
mach_topology.cores * sizeof(struct cpuinfo_core), mach_topology.cores);
goto cleanup;
}
/* On x86 cluster of cores is a physical package */
clusters = calloc(mach_topology.packages, sizeof(struct cpuinfo_cluster));
if (clusters == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" core clusters",
mach_topology.packages * sizeof(struct cpuinfo_cluster), mach_topology.packages);
goto cleanup;
}
packages = calloc(mach_topology.packages, sizeof(struct cpuinfo_package));
if (packages == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" physical packages",
mach_topology.packages * sizeof(struct cpuinfo_package), mach_topology.packages);
goto cleanup;
}
struct cpuinfo_x86_processor x86_processor;
memset(&x86_processor, 0, sizeof(x86_processor));
cpuinfo_x86_init_processor(&x86_processor);
char brand_string[48];
cpuinfo_x86_normalize_brand_string(x86_processor.brand_string, brand_string);
const uint32_t threads_per_core = mach_topology.threads / mach_topology.cores;
const uint32_t threads_per_package = mach_topology.threads / mach_topology.packages;
const uint32_t cores_per_package = mach_topology.cores / mach_topology.packages;
for (uint32_t i = 0; i < mach_topology.packages; i++) {
clusters[i] = (struct cpuinfo_cluster) {
.processor_start = i * threads_per_package,
.processor_count = threads_per_package,
.core_start = i * cores_per_package,
.core_count = cores_per_package,
.cluster_id = 0,
.package = packages + i,
.vendor = x86_processor.vendor,
.uarch = x86_processor.uarch,
.cpuid = x86_processor.cpuid,
};
packages[i].processor_start = i * threads_per_package;
packages[i].processor_count = threads_per_package;
packages[i].core_start = i * cores_per_package;
packages[i].core_count = cores_per_package;
packages[i].cluster_start = i;
packages[i].cluster_count = 1;
cpuinfo_x86_format_package_name(x86_processor.vendor, brand_string, packages[i].name);
}
for (uint32_t i = 0; i < mach_topology.cores; i++) {
cores[i] = (struct cpuinfo_core) {
.processor_start = i * threads_per_core,
.processor_count = threads_per_core,
.core_id = i % cores_per_package,
.cluster = clusters + i / cores_per_package,
.package = packages + i / cores_per_package,
.vendor = x86_processor.vendor,
.uarch = x86_processor.uarch,
.cpuid = x86_processor.cpuid,
};
}
for (uint32_t i = 0; i < mach_topology.threads; i++) {
const uint32_t smt_id = i % threads_per_core;
const uint32_t core_id = i / threads_per_core;
const uint32_t package_id = i / threads_per_package;
/* Reconstruct APIC IDs from topology components */
const uint32_t thread_bits_mask = bit_mask(x86_processor.topology.thread_bits_length);
const uint32_t core_bits_mask = bit_mask(x86_processor.topology.core_bits_length);
const uint32_t package_bits_offset = max(
x86_processor.topology.thread_bits_offset + x86_processor.topology.thread_bits_length,
x86_processor.topology.core_bits_offset + x86_processor.topology.core_bits_length);
const uint32_t apic_id =
((smt_id & thread_bits_mask) << x86_processor.topology.thread_bits_offset) |
((core_id & core_bits_mask) << x86_processor.topology.core_bits_offset) |
(package_id << package_bits_offset);
cpuinfo_log_debug("reconstructed APIC ID 0x%08"PRIx32" for thread %"PRIu32, apic_id, i);
processors[i].smt_id = smt_id;
processors[i].core = cores + i / threads_per_core;
processors[i].cluster = clusters + i / threads_per_package;
processors[i].package = packages + i / threads_per_package;
processors[i].apic_id = apic_id;
}
uint32_t threads_per_l1 = 0, l1_count = 0;
if (x86_processor.cache.l1i.size != 0 || x86_processor.cache.l1d.size != 0) {
threads_per_l1 = mach_topology.threads_per_cache[1];
if (threads_per_l1 == 0) {
/* Assume that threads on the same core share L1 */
threads_per_l1 = mach_topology.threads / mach_topology.cores;
cpuinfo_log_warning("Mach kernel did not report number of threads sharing L1 cache; assume %"PRIu32,
threads_per_l1);
}
l1_count = mach_topology.threads / threads_per_l1;
cpuinfo_log_debug("detected %"PRIu32" L1 caches", l1_count);
}
uint32_t threads_per_l2 = 0, l2_count = 0;
if (x86_processor.cache.l2.size != 0) {
threads_per_l2 = mach_topology.threads_per_cache[2];
if (threads_per_l2 == 0) {
if (x86_processor.cache.l3.size != 0) {
/* This is not a last-level cache; assume that threads on the same core share L2 */
threads_per_l2 = mach_topology.threads / mach_topology.cores;
} else {
/* This is a last-level cache; assume that threads on the same package share L2 */
threads_per_l2 = mach_topology.threads / mach_topology.packages;
}
cpuinfo_log_warning("Mach kernel did not report number of threads sharing L2 cache; assume %"PRIu32,
threads_per_l2);
}
l2_count = mach_topology.threads / threads_per_l2;
cpuinfo_log_debug("detected %"PRIu32" L2 caches", l2_count);
}
uint32_t threads_per_l3 = 0, l3_count = 0;
if (x86_processor.cache.l3.size != 0) {
threads_per_l3 = mach_topology.threads_per_cache[3];
if (threads_per_l3 == 0) {
/*
* Assume that threads on the same package share L3.
* However, is it not necessarily the last-level cache (there may be L4 cache as well)
*/
threads_per_l3 = mach_topology.threads / mach_topology.packages;
cpuinfo_log_warning("Mach kernel did not report number of threads sharing L3 cache; assume %"PRIu32,
threads_per_l3);
}
l3_count = mach_topology.threads / threads_per_l3;
cpuinfo_log_debug("detected %"PRIu32" L3 caches", l3_count);
}
uint32_t threads_per_l4 = 0, l4_count = 0;
if (x86_processor.cache.l4.size != 0) {
threads_per_l4 = mach_topology.threads_per_cache[4];
if (threads_per_l4 == 0) {
/*
* Assume that all threads share this L4.
* As of now, L4 cache exists only on notebook x86 CPUs, which are single-package,
* but multi-socket systems could have shared L4 (like on IBM POWER8).
*/
threads_per_l4 = mach_topology.threads;
cpuinfo_log_warning("Mach kernel did not report number of threads sharing L4 cache; assume %"PRIu32,
threads_per_l4);
}
l4_count = mach_topology.threads / threads_per_l4;
cpuinfo_log_debug("detected %"PRIu32" L4 caches", l4_count);
}
if (x86_processor.cache.l1i.size != 0) {
l1i = calloc(l1_count, sizeof(struct cpuinfo_cache));
if (l1i == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" L1I caches",
l1_count * sizeof(struct cpuinfo_cache), l1_count);
return;
}
for (uint32_t c = 0; c < l1_count; c++) {
l1i[c] = (struct cpuinfo_cache) {
.size = x86_processor.cache.l1i.size,
.associativity = x86_processor.cache.l1i.associativity,
.sets = x86_processor.cache.l1i.sets,
.partitions = x86_processor.cache.l1i.partitions,
.line_size = x86_processor.cache.l1i.line_size,
.flags = x86_processor.cache.l1i.flags,
.processor_start = c * threads_per_l1,
.processor_count = threads_per_l1,
};
}
for (uint32_t t = 0; t < mach_topology.threads; t++) {
processors[t].cache.l1i = &l1i[t / threads_per_l1];
}
}
if (x86_processor.cache.l1d.size != 0) {
l1d = calloc(l1_count, sizeof(struct cpuinfo_cache));
if (l1d == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" L1D caches",
l1_count * sizeof(struct cpuinfo_cache), l1_count);
return;
}
for (uint32_t c = 0; c < l1_count; c++) {
l1d[c] = (struct cpuinfo_cache) {
.size = x86_processor.cache.l1d.size,
.associativity = x86_processor.cache.l1d.associativity,
.sets = x86_processor.cache.l1d.sets,
.partitions = x86_processor.cache.l1d.partitions,
.line_size = x86_processor.cache.l1d.line_size,
.flags = x86_processor.cache.l1d.flags,
.processor_start = c * threads_per_l1,
.processor_count = threads_per_l1,
};
}
for (uint32_t t = 0; t < mach_topology.threads; t++) {
processors[t].cache.l1d = &l1d[t / threads_per_l1];
}
}
if (l2_count != 0) {
l2 = calloc(l2_count, sizeof(struct cpuinfo_cache));
if (l2 == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" L2 caches",
l2_count * sizeof(struct cpuinfo_cache), l2_count);
return;
}
for (uint32_t c = 0; c < l2_count; c++) {
l2[c] = (struct cpuinfo_cache) {
.size = x86_processor.cache.l2.size,
.associativity = x86_processor.cache.l2.associativity,
.sets = x86_processor.cache.l2.sets,
.partitions = x86_processor.cache.l2.partitions,
.line_size = x86_processor.cache.l2.line_size,
.flags = x86_processor.cache.l2.flags,
.processor_start = c * threads_per_l2,
.processor_count = threads_per_l2,
};
}
for (uint32_t t = 0; t < mach_topology.threads; t++) {
processors[t].cache.l2 = &l2[t / threads_per_l2];
}
}
if (l3_count != 0) {
l3 = calloc(l3_count, sizeof(struct cpuinfo_cache));
if (l3 == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" L3 caches",
l3_count * sizeof(struct cpuinfo_cache), l3_count);
return;
}
for (uint32_t c = 0; c < l3_count; c++) {
l3[c] = (struct cpuinfo_cache) {
.size = x86_processor.cache.l3.size,
.associativity = x86_processor.cache.l3.associativity,
.sets = x86_processor.cache.l3.sets,
.partitions = x86_processor.cache.l3.partitions,
.line_size = x86_processor.cache.l3.line_size,
.flags = x86_processor.cache.l3.flags,
.processor_start = c * threads_per_l3,
.processor_count = threads_per_l3,
};
}
for (uint32_t t = 0; t < mach_topology.threads; t++) {
processors[t].cache.l3 = &l3[t / threads_per_l3];
}
}
if (l4_count != 0) {
l4 = calloc(l4_count, sizeof(struct cpuinfo_cache));
if (l4 == NULL) {
cpuinfo_log_error("failed to allocate %zu bytes for descriptions of %"PRIu32" L4 caches",
l4_count * sizeof(struct cpuinfo_cache), l4_count);
return;
}
for (uint32_t c = 0; c < l4_count; c++) {
l4[c] = (struct cpuinfo_cache) {
.size = x86_processor.cache.l4.size,
.associativity = x86_processor.cache.l4.associativity,
.sets = x86_processor.cache.l4.sets,
.partitions = x86_processor.cache.l4.partitions,
.line_size = x86_processor.cache.l4.line_size,
.flags = x86_processor.cache.l4.flags,
.processor_start = c * threads_per_l4,
.processor_count = threads_per_l4,
};
}
for (uint32_t t = 0; t < mach_topology.threads; t++) {
processors[t].cache.l4 = &l4[t / threads_per_l4];
}
}
/* Commit changes */
cpuinfo_processors = processors;
cpuinfo_cores = cores;
cpuinfo_clusters = clusters;
cpuinfo_packages = packages;
cpuinfo_cache[cpuinfo_cache_level_1i] = l1i;
cpuinfo_cache[cpuinfo_cache_level_1d] = l1d;
cpuinfo_cache[cpuinfo_cache_level_2] = l2;
cpuinfo_cache[cpuinfo_cache_level_3] = l3;
cpuinfo_cache[cpuinfo_cache_level_4] = l4;
cpuinfo_processors_count = mach_topology.threads;
cpuinfo_cores_count = mach_topology.cores;
cpuinfo_clusters_count = mach_topology.packages;
cpuinfo_packages_count = mach_topology.packages;
cpuinfo_cache_count[cpuinfo_cache_level_1i] = l1_count;
cpuinfo_cache_count[cpuinfo_cache_level_1d] = l1_count;
cpuinfo_cache_count[cpuinfo_cache_level_2] = l2_count;
cpuinfo_cache_count[cpuinfo_cache_level_3] = l3_count;
cpuinfo_cache_count[cpuinfo_cache_level_4] = l4_count;
cpuinfo_max_cache_size = cpuinfo_compute_max_cache_size(&processors[0]);
cpuinfo_global_uarch = (struct cpuinfo_uarch_info) {
.uarch = x86_processor.uarch,
.cpuid = x86_processor.cpuid,
.processor_count = mach_topology.threads,
.core_count = mach_topology.cores,
};
__sync_synchronize();
cpuinfo_is_initialized = true;
processors = NULL;
cores = NULL;
clusters = NULL;
packages = NULL;
l1i = l1d = l2 = l3 = l4 = NULL;
cleanup:
free(processors);
free(cores);
free(clusters);
free(packages);
free(l1i);
free(l1d);
free(l2);
free(l3);
free(l4);
}