Ignore disabled hyperthreads (#291)
Only consider processors with an APIC_ID as valid.
For processors with Hyperthreads but disabled SMT the APIC_ID will never be set and stays zero for the "disabled" threads.
Among other inconsistencies this causes the first active thread/processor to be considered "the same" as all the disabled ones as they share `APIC_ID=0`
It also doesn't make sense to make and decisions based on the APIC_ID if we don't have any information on it.
diff --git a/src/x86/linux/init.c b/src/x86/linux/init.c
index d2b2d47..86e7e67 100644
--- a/src/x86/linux/init.c
+++ b/src/x86/linux/init.c
@@ -47,7 +47,6 @@
uint32_t linux_processors_count,
const struct cpuinfo_x86_linux_processor linux_processors[restrict static linux_processors_count],
const struct cpuinfo_x86_processor processor[restrict static 1],
- uint32_t valid_processor_mask,
uint32_t llc_apic_bits,
uint32_t cores_count_ptr[restrict static 1],
uint32_t clusters_count_ptr[restrict static 1],
@@ -70,7 +69,7 @@
uint32_t last_l1i_id = UINT32_MAX, last_l1d_id = UINT32_MAX;
uint32_t last_l2_id = UINT32_MAX, last_l3_id = UINT32_MAX, last_l4_id = UINT32_MAX;
for (uint32_t i = 0; i < linux_processors_count; i++) {
- if (bitmask_all(linux_processors[i].flags, valid_processor_mask)) {
+ if (bitmask_all(linux_processors[i].flags, CPUINFO_LINUX_FLAG_VALID)) {
const uint32_t apic_id = linux_processors[i].apic_id;
cpuinfo_log_debug(
"APID ID %" PRIu32 ": system processor %" PRIu32,
@@ -167,13 +166,13 @@
const uint32_t max_present_processors_count = 1 + cpuinfo_linux_get_max_present_processor(max_processors_count);
cpuinfo_log_debug("maximum present processors count: %" PRIu32, max_present_processors_count);
- uint32_t valid_processor_mask = 0;
+ uint32_t valid_processor_mask = CPUINFO_LINUX_FLAG_APIC_ID;
uint32_t x86_linux_processors_count = max_processors_count;
if (max_present_processors_count != 0) {
x86_linux_processors_count = min(x86_linux_processors_count, max_present_processors_count);
- valid_processor_mask = CPUINFO_LINUX_FLAG_PRESENT;
+ valid_processor_mask |= CPUINFO_LINUX_FLAG_PRESENT;
} else {
- valid_processor_mask = CPUINFO_LINUX_FLAG_PROC_CPUINFO;
+ valid_processor_mask |= CPUINFO_LINUX_FLAG_PROC_CPUINFO;
}
if (max_possible_processors_count != 0) {
x86_linux_processors_count = min(x86_linux_processors_count, max_possible_processors_count);
@@ -260,7 +259,6 @@
x86_linux_processors_count,
x86_linux_processors,
&x86_processor,
- valid_processor_mask,
llc_apic_bits,
&cores_count,
&clusters_count,
