Commit 3abc1a2b authored by Keqian Zhu's avatar Keqian Zhu Committed by zhuyanting
Browse files

arm/virt: Support CPU cold plug 



This adds CPU cold plug support to arm virt machine board.
CPU cold plug means adding CPU by using "-device xx-arm-cpu"
when we bring up Qemu.

Signed-off-by: default avatarKeqian Zhu <zhukeqian1@huawei.com>
parent a43d51d1

hw/arm/virt.c

+19 −17
Original line number Diff line number Diff line
@@ -2093,25 +2093,12 @@ static void virt_cpu_pre_plug(HotplugHandler *hotplug_dev, 
    int smp_cores = ms->smp.cores;

    int smp_threads = ms->smp.threads;



    /* Some hotplug capability checks */



    if (!object_dynamic_cast(OBJECT(cpu), ms->cpu_type)) {

        error_setg(errp, "Invalid CPU type, expected cpu type: '%s'",

                   ms->cpu_type);

        return;

    }



    if (dev->hotplugged && !vms->acpi_dev) {

        error_setg(errp, "CPU hotplug is disabled: missing acpi device.");

        return;

    }



    if (dev->hotplugged && !vms->cpu_hotplug_enabled) {

        error_setg(errp, "CPU hotplug is disabled: "

                         "should use AArch64 CPU and GICv3.");

        return;

    }



    /* if cpu idx is not set, set it based on socket/core/thread properties */

    if (cs->cpu_index == UNASSIGNED_CPU_INDEX) {

        int max_socket = ms->smp.max_cpus / smp_threads / smp_cores;
@@ -2137,6 +2124,20 @@ static void virt_cpu_pre_plug(HotplugHandler *hotplug_dev, 
        cs->cpu_index = idx_from_topo_ids(smp_cores, smp_threads, &topo);

    }



    /* Some hotplug capability checks */

    if (cs->cpu_index >= ms->smp.cpus) {

        if (!vms->acpi_dev) {

            error_setg(errp, "CPU cold/hot plug is disabled: "

                             "missing acpi device.");

            return;

        }

        if (!vms->cpu_hotplug_enabled) {

            error_setg(errp, "CPU cold/hot plug is disabled: "

                             "should use AArch64 CPU and GICv3.");

            return;

        }

    }



    /* if 'address' properties socket-id/core-id/thread-id are not set, set them

     * so that machine_query_hotpluggable_cpus would show correct values

     */
@@ -2237,7 +2238,8 @@ static void virt_cpu_plug(HotplugHandler *hotplug_dev, 
    ARMGICv3CommonClass *agcc;

    Error *local_err = NULL;



    if (dev->hotplugged) {

    /* For CPU that is cold/hot plugged */

    if (ncpu >= ms->smp.cpus) {

        /* Realize GIC related parts of CPU */

        assert(vms->gic_version == 3);

        gicv3 = ARM_GICV3_COMMON(vms->gic);
@@ -2250,11 +2252,11 @@ static void virt_cpu_plug(HotplugHandler *hotplug_dev, 
        cpu_hotplug_register_reset(ncpu);

        cpu_hotplug_reset_manually(ncpu);

        cpu_synchronize_post_reset(cs);

    }



        if (kvm_enabled()) {

    if (dev->hotplugged && kvm_enabled()) {

        resume_all_vcpus();

    }

    }



    if (vms->acpi_dev) {

        hotplug_handler_plug(HOTPLUG_HANDLER(vms->acpi_dev), dev, &local_err);