core: release core reminders

We now release using unPin the VdsCpuUnit we need. This is good for
`dedicated` policy. When we are handling `isolate-threads` policy we
need to release the whole core. Otherwise the engine thinks it's taken.

Change-Id: I0b028e0dc5db72f5ef3099059f355d975a81fc90
Bug-Url: https://bugzilla.redhat.com/2103620
Signed-off-by: Liran Rotenberg <lrotenbe@redhat.com>

backend/manager/modules/bll/src/main/java/org/ovirt/engine/core/bll/scheduling/utils/VdsCpuUnitPinningHelper.java

@@ -194,10 +194,18 @@ private List<VdsCpuUnit> allocateDedicatedCpus(List<VdsCpuUnit> cpuTopology, VM
             }
             socketsLeft -= coreCount / vm.getCpuPerSocket();
             int coresReminder = coreCount % vm.getCpuPerSocket();
-            for (int i = 0; i < coresReminder * vm.getThreadsPerCpu(); i++) {
+            int numOfCpusToRemove = vm.getCpuPinningPolicy() == CpuPinningPolicy.DEDICATED ?
+                    coresReminder * vm.getThreadsPerCpu() : coresReminder;
+            for (int i = 0; i < numOfCpusToRemove; i++) {
                 if (!cpusToBeAllocated.isEmpty()) {
-                    VdsCpuUnit releasedCpu = cpusToBeAllocated.remove(cpusToBeAllocated.size() - 1);
-                    releasedCpu.unPinVm(vm.getId());
+                    switch(vm.getCpuPinningPolicy()) {
+                        case DEDICATED:
+                            releaseDedicatedCpu(vm.getId(), cpusToBeAllocated);
+                            break;
+                        case ISOLATE_THREADS:
+                            releaseIsolateThreadsCpu(vm.getId(), cpusToBeAllocated);
+                            numOfAllocatedCPUs--;
+                    }
                 }
             }
 
@@ -210,6 +218,22 @@ private List<VdsCpuUnit> allocateDedicatedCpus(List<VdsCpuUnit> cpuTopology, VM
         return cpusToBeAllocated;
     }
 
+    private void releaseDedicatedCpu(Guid vmId, List<VdsCpuUnit> cpusToBeAllocated) {
+        VdsCpuUnit releasedCpu = cpusToBeAllocated.remove(cpusToBeAllocated.size() - 1);
+        releasedCpu.unPinVm(vmId);
+    }
+
+    private void releaseIsolateThreadsCpu(Guid vmId, List<VdsCpuUnit> cpusToBeAllocated) {
+        VdsCpuUnit cpuUnit = cpusToBeAllocated.get(cpusToBeAllocated.size() - 1);
+        int coreId  = cpuUnit.getCore();
+        int socketId = cpuUnit.getSocket();
+        List<VdsCpuUnit> cpusToRemove = getCpusInCore(getCoresInSocket(cpusToBeAllocated, socketId), coreId);
+        cpusToRemove.forEach(vdsCpuUnit -> {
+            vdsCpuUnit.unPinVm(vmId);
+            cpusToBeAllocated.remove(vdsCpuUnit);
+        });
+    }
+
     private int countTakenCores(List<VdsCpuUnit> cpuTopology) {
         if (cpuTopology.isEmpty()) {
             return 0;