On Fri, Feb 26, 2016 at 02:03:57PM +0100, Thomas Huth wrote:
> On 25.02.2016 17:22, Bharata B Rao wrote:
> > Set up device tree entries for the hotplugged CPU core and use the
> > exising EPOW event infrastructure to send CPU hotplug notification to
> > the guest.
> >
> > Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com>
> > ---
> > hw/ppc/spapr.c | 136
> > ++++++++++++++++++++++++++++++++++++++++++++++++-
> > hw/ppc/spapr_events.c | 3 ++
> > hw/ppc/spapr_rtas.c | 24 +++++++++
> > include/hw/ppc/spapr.h | 1 +
> > 4 files changed, 163 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index 1f0d232..780cd00 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -603,6 +603,18 @@ static void spapr_populate_cpu_dt(CPUState *cs, void
> > *fdt, int offset,
> > size_t page_sizes_prop_size;
> > uint32_t vcpus_per_socket = smp_threads * smp_cores;
> > uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)};
> > + sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(qdev_get_machine());
> > + sPAPRDRConnector *drc;
> > + sPAPRDRConnectorClass *drck;
> > + int drc_index;
> > +
> > + if (smc->dr_cpu_enabled) {
> > + drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, index);
> > + g_assert(drc);
> > + drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc);
> > + drc_index = drck->get_index(drc);
> > + _FDT((fdt_setprop_cell(fdt, offset, "ibm,my-drc-index",
> > drc_index)));
> > + }
> >
> > /* Note: we keep CI large pages off for now because a 64K capable guest
> > * provisioned with large pages might otherwise try to map a qemu
> > @@ -987,6 +999,16 @@ static void spapr_finalize_fdt(sPAPRMachineState
> > *spapr,
> > _FDT(spapr_drc_populate_dt(fdt, 0, NULL,
> > SPAPR_DR_CONNECTOR_TYPE_LMB));
> > }
> >
> > + if (smc->dr_cpu_enabled) {
> > + int offset = fdt_path_offset(fdt, "/cpus");
> > + ret = spapr_drc_populate_dt(fdt, offset, NULL,
> > + SPAPR_DR_CONNECTOR_TYPE_CPU);
> > + if (ret < 0) {
> > + fprintf(stderr, "Couldn't set up CPU DR device tree
> > properties\n");
>
> I think it's better to use error_report() nowadays instead.
Yeah, have been carrying this old hunk, will fix.
>
> > + exit(1);
> > + }
> > + }
> > +
> > _FDT((fdt_pack(fdt)));
> >
> > if (fdt_totalsize(fdt) > FDT_MAX_SIZE) {
> > @@ -1759,6 +1781,7 @@ static void ppc_spapr_init(MachineState *machine)
> > char *filename;
> > int spapr_cores = smp_cpus / smp_threads;
> > int spapr_max_cores = max_cpus / smp_threads;
> > + int smt = kvmppc_smt_threads();
> >
> > msi_supported = true;
> >
> > @@ -1813,6 +1836,15 @@ static void ppc_spapr_init(MachineState *machine)
> > spapr_validate_node_memory(machine, &error_fatal);
> > }
> >
> > + if (smc->dr_cpu_enabled) {
> > + for (i = 0; i < spapr_max_cores; i++) {
> > + sPAPRDRConnector *drc =
> > + spapr_dr_connector_new(OBJECT(spapr),
> > + SPAPR_DR_CONNECTOR_TYPE_CPU, i *
> > smt);
> > + qemu_register_reset(spapr_drc_reset, drc);
> > + }
> > + }
> > +
> > /* init CPUs */
> > if (machine->cpu_model == NULL) {
> > machine->cpu_model = kvm_enabled() ? "host" : "POWER7";
> > @@ -2247,6 +2279,88 @@ out:
> > error_propagate(errp, local_err);
> > }
> >
> > +static void *spapr_populate_hotplug_cpu_dt(DeviceState *dev, CPUState *cs,
> > + int *fdt_offset,
> > + sPAPRMachineState *spapr)
> > +{
> > + PowerPCCPU *cpu = POWERPC_CPU(cs);
> > + DeviceClass *dc = DEVICE_GET_CLASS(cs);
> > + int id = ppc_get_vcpu_dt_id(cpu);
> > + void *fdt;
> > + int offset, fdt_size;
> > + char *nodename;
> > +
> > + fdt = create_device_tree(&fdt_size);
> > + nodename = g_strdup_printf("%s@%x", dc->fw_name, id);
> > + offset = fdt_add_subnode(fdt, 0, nodename);
> > +
> > + spapr_populate_cpu_dt(cs, fdt, offset, spapr);
> > + g_free(nodename);
> > +
> > + *fdt_offset = offset;
> > + return fdt;
> > +}
> > +
> > +static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
> > + Error **errp)
> > +{
> > + sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(qdev_get_machine());
> > + sPAPRMachineState *ms = SPAPR_MACHINE(qdev_get_machine());
> > + sPAPRCPUCore *core = SPAPR_CPU_CORE(OBJECT(dev));
> > + PowerPCCPU *cpu = &core->threads[0];
> > + CPUState *cs = CPU(cpu);
> > + int id = ppc_get_vcpu_dt_id(cpu);
> > + sPAPRDRConnector *drc =
> > + spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, id);
> > + sPAPRDRConnectorClass *drck;
> > + Error *local_err = NULL;
> > + void *fdt = NULL;
> > + int fdt_offset = 0;
> > +
> > + if (!smc->dr_cpu_enabled) {
> > + /*
> > + * This is a cold plugged CPU core but the machine doesn't support
> > + * DR. So skip the hotplug path ensuring that the core is brought
> > + * up online with out an associated DR connector.
> > + */
> > + return;
> > + }
> > +
> > + g_assert(drc);
> > +
> > + /*
> > + * Setup CPU DT entries only for hotplugged CPUs. For boot time or
> > + * coldplugged CPUs DT entries are setup in spapr_finalize_fdt().
> > + */
> > + if (dev->hotplugged) {
> > + fdt = spapr_populate_hotplug_cpu_dt(dev, cs, &fdt_offset, ms);
> > + dev->hotplugged = true;
>
> That looks strange ... why "dev->hotplugged = true" after you've already
> checked that with the above if-statement?
Yeah this is a remnant of the implmentation that was based on David's proposal
where all the devices were pre-created and I had to set dev->hotplugged
manually here. Will remove as it is not needed here in this device_add
based implementation.
Regards,
Bharata.
