Normalize physical core ID when showCPUSMTLabels is set

linux/LinuxMachine.c

@@ -731,6 +731,26 @@ static void LinuxMachine_computeThreadIndices(LinuxMachine* this) {
       }
       cpus[i].threadIndex = threadIndex;
    }
+
+   /* Now compute a normalized physical core index for each CPU.
+      On many systems, this index will match the following:
+        physicalID*(maxPhysicalID+1)+coreID
+      But there are some systems where this is not true, either
+      because CoreIDs are not contiguous or because cpus are
+      enumerated in an alternative order, or both. */
+   for (size_t i = 1; i <= super->existingCPUs; i++) {
+      cpus[i].coreIndex = 0;
+      for (size_t j = i - 1; j >= 1; j--) {
+         if (cpus[i].threadIndex == cpus[j].threadIndex) {
+            cpus[i].coreIndex = cpus[j].coreIndex + 1;
+            break;
+         }
+      }
+   }
+
+   /* Set core & thread indices to zero for cpu0 (average) */
+   cpus[0].coreIndex = 0;
+   cpus[0].threadIndex = 0;
 }
 
 static void LinuxMachine_scanCPUFrequency(LinuxMachine* this) {
@@ -850,9 +870,7 @@ int Machine_getCPUPhysicalCoreID(const Machine* super, unsigned int id) {
    const LinuxMachine* this = (const LinuxMachine*) super;
 
    assert(id < super->existingCPUs);
-
-   const CPUData* cpu = &this->cpuData[id + 1];
-   return cpu->physicalID * (this->maxCoreID + 1) + cpu->coreID;
+   return this->cpuData[id + 1].coreIndex;
 }
 
 int Machine_getCPUThreadIndex(const Machine* super, unsigned int id) {

linux/LinuxMachine.h

@@ -54,6 +54,7 @@ typedef struct CPUData_ {
    int physicalID;      /* different for each CPU socket */
    int coreID;          /* same for hyperthreading */
    int ccdID;           /* same for each AMD chiplet */
+   int coreIndex;       /* Normalized physical core ID */
    int threadIndex;     /* SMT thread index: 0 for first thread, 1 for second, etc. */
 
    bool online;