Introduce UnplugCpus() which maps each APIC ID being unplugged onto the hardware ID of the processor and informs PiSmmCpuDxeSmm of removal by calling EFI_SMM_CPU_SERVICE_PROTOCOL.RemoveProcessor().
With this change we handle the first phase of unplug where we collect the CPUs that need to be unplugged and mark them for removal in SMM data structures. Cc: Laszlo Ersek <ler...@redhat.com> Cc: Jordan Justen <jordan.l.jus...@intel.com> Cc: Ard Biesheuvel <ard.biesheu...@arm.com> Cc: Igor Mammedov <imamm...@redhat.com> Cc: Boris Ostrovsky <boris.ostrov...@oracle.com> Cc: Aaron Young <aaron.yo...@oracle.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3132 Signed-off-by: Ankur Arora <ankur.a.ar...@oracle.com> --- OvmfPkg/CpuHotplugSmm/CpuHotplug.c | 84 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) diff --git a/OvmfPkg/CpuHotplugSmm/CpuHotplug.c b/OvmfPkg/CpuHotplugSmm/CpuHotplug.c index 05b1f8cb63a6..70d69f6ed65b 100644 --- a/OvmfPkg/CpuHotplugSmm/CpuHotplug.c +++ b/OvmfPkg/CpuHotplugSmm/CpuHotplug.c @@ -188,6 +188,88 @@ RevokeNewSlot: } /** + Process to be hot-unplugged CPUs, per QemuCpuhpCollectApicIds(). + + For each such CPU, report the CPU to PiSmmCpuDxeSmm via + EFI_SMM_CPU_SERVICE_PROTOCOL. If the to be hot-unplugged CPU is + unknown, skip it silently. + + @param[in] ToUnplugApicIds The APIC IDs of the CPUs that are about to be + hot-unplugged. + + @param[in] ToUnplugCount The number of filled-in APIC IDs in + ToUnplugApicIds. + + @retval EFI_SUCCESS Known APIC IDs have been removed from SMM data + structures. + + @return Error codes propagated from + mMmCpuService->RemoveProcessor(). + +**/ +STATIC +EFI_STATUS +UnplugCpus ( + IN APIC_ID *ToUnplugApicIds, + IN UINT32 ToUnplugCount + ) +{ + EFI_STATUS Status; + UINT32 ToUnplugIdx; + UINTN ProcessorNum; + + ToUnplugIdx = 0; + while (ToUnplugIdx < ToUnplugCount) { + APIC_ID RemoveApicId; + + RemoveApicId = ToUnplugApicIds[ToUnplugIdx]; + + // + // mCpuHotPlugData->ApicId maps ProcessorNum -> ApicId. Use it to find + // the ProcessorNum for the APIC ID to be removed. + // + for (ProcessorNum = 0; + ProcessorNum < mCpuHotPlugData->ArrayLength; + ProcessorNum++) { + if (mCpuHotPlugData->ApicId[ProcessorNum] == RemoveApicId) { + break; + } + } + + // + // Ignore the unplug if APIC ID not found + // + if (ProcessorNum == mCpuHotPlugData->ArrayLength) { + DEBUG ((DEBUG_INFO, "%a: did not find APIC ID " FMT_APIC_ID + " to unplug\n", __FUNCTION__, RemoveApicId)); + ToUnplugIdx++; + continue; + } + + // + // Mark ProcessorNum for removal from SMM data structures + // + Status = mMmCpuService->RemoveProcessor (mMmCpuService, ProcessorNum); + + if (EFI_ERROR (Status)) { + DEBUG ((DEBUG_ERROR, "%a: RemoveProcessor(" FMT_APIC_ID "): %r\n", + __FUNCTION__, RemoveApicId, Status)); + goto Fatal; + } + + ToUnplugIdx++; + } + + // + // We've removed this set of APIC IDs from SMM data structures. + // + return EFI_SUCCESS; + +Fatal: + return Status; +} + +/** CPU Hotplug MMI handler function. This is a root MMI handler. @@ -303,6 +385,8 @@ CpuHotplugMmi ( if (PluggedCount > 0) { Status = ProcessHotAddedCpus (mPluggedApicIds, PluggedCount); + } else if (ToUnplugCount > 0) { + Status = UnplugCpus (mToUnplugApicIds, ToUnplugCount); } if (EFI_ERROR(Status)) { -- 2.9.3 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#70877): https://edk2.groups.io/g/devel/message/70877 Mute This Topic: https://groups.io/mt/80199964/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
