On Tue, Feb 12, 2019 at 10:48:24PM +0100, Laurent Vivier wrote: > spapr_possible_cpu_arch_ids() counts only cores, and so > the number of available CPUs is the number of vCPU divided > by smp_threads. > > ... -smp 4,maxcpus=8,cores=2,threads=2,sockets=2 -numa node,cpus=0,cpus=1 \ > -numa node,cpus=3,cpus=4 \ > -numa node -numa node > > This generates (info hotpluggable-cpus) > > node-id: 0 core-id: 0 thread-id: 0 [thread-id: 1] > node-id: 0 core-id: 6 thread-id: 0 [thread-id: 1] > node-id: 1 core-id: 2 thread-id: 0 [thread-id: 1] > node-id: 1 core-id: 4 thread-id: 0 [thread-id: 1] > > And this command line generates the following error: > > CPU(s) not present in any NUMA nodes: CPU 3 [core-id: 6] > > That is wrong because CPU 3 [core-id: 6] is assigned to node-id 0 > Moreover "cpus=4" is not valid, because it means core-id 8 but > maxcpus is 8. > > With this patch we have now: > > node-id: 0 core-id: 0 thread-id: 0 > node-id: 0 core-id: 0 thread-id: 1 > node-id: 0 core-id: 1 thread-id: 0 > node-id: 1 core-id: 1 thread-id: 1 > node-id: 0 core-id: 2 thread-id: 1 > node-id: 1 core-id: 2 thread-id: 0 > node-id: 0 core-id: 3 thread-id: 1 > node-id: 0 core-id: 3 thread-id: 0 I'm afraid this is not the right solution. The point of the hotpluggable cpus table is that it has exactly one entry for each hotpluggable unit. For PAPR that's a core, not a thread. So, the problem is with how the NUMA configuration code is interpreting possible-cpus, not how the machine is building the table. > CPUs 0 (core-id: 0 thread-id: 0) and 1 (core-id: 0 thread-id: 1) are > correctly assigned to node-id 0, CPUs 3 (core-id: 1 thread-id: 1) and > 4 (core-id: 2 thread-id: 0) are correctly assigned to node-id 1. > All other CPUs are assigned to node-id 0 by default. > > And the error message is also correct: > > CPU(s) not present in any NUMA nodes: CPU 2 [core-id: 1, thread-id: 0], \ > CPU 5 [core-id: 2, thread-id: 1], \ > CPU 6 [core-id: 3, thread-id: 0], \ > CPU 7 [core-id: 3, thread-id: 1] > > Fixes: ec78f8114bc4 ("numa: use possible_cpus for not mapped CPUs check") > Cc: imammedo@redhat.com > > Before commit ec78f8114bc4, output was correct: > > CPU(s) not present in any NUMA nodes: 2 5 6 7 > > Signed-off-by: Laurent Vivier > --- > hw/ppc/spapr.c | 33 +++++++++++++-------------------- > 1 file changed, 13 insertions(+), 20 deletions(-) > > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 332cba89d425..7196ba09da34 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -2404,15 +2404,13 @@ static void spapr_validate_node_memory(MachineState *machine, Error **errp) > /* find cpu slot in machine->possible_cpus by core_id */ > static CPUArchId *spapr_find_cpu_slot(MachineState *ms, uint32_t id, int *idx) > { > - int index = id / smp_threads; > - > - if (index >= ms->possible_cpus->len) { > + if (id >= ms->possible_cpus->len) { > return NULL; > } > if (idx) { > - *idx = index; > + *idx = id; > } > - return &ms->possible_cpus->cpus[index]; > + return &ms->possible_cpus->cpus[id]; > } > > static void spapr_set_vsmt_mode(sPAPRMachineState *spapr, Error **errp) > @@ -2514,7 +2512,7 @@ static void spapr_init_cpus(sPAPRMachineState *spapr) > error_report("This machine version does not support CPU hotplug"); > exit(1); > } > - boot_cores_nr = possible_cpus->len; > + boot_cores_nr = possible_cpus->len / smp_threads; > } > > if (smc->pre_2_10_has_unused_icps) { > @@ -2528,7 +2526,7 @@ static void spapr_init_cpus(sPAPRMachineState *spapr) > } > } > > - for (i = 0; i < possible_cpus->len; i++) { > + for (i = 0; i < possible_cpus->len / smp_threads; i++) { > int core_id = i * smp_threads; > > if (mc->has_hotpluggable_cpus) { > @@ -3795,21 +3793,16 @@ spapr_cpu_index_to_props(MachineState *machine, unsigned cpu_index) > > static int64_t spapr_get_default_cpu_node_id(const MachineState *ms, int idx) > { > - return idx / smp_cores % nb_numa_nodes; > + return idx / (smp_cores * smp_threads) % nb_numa_nodes; > } > > static const CPUArchIdList *spapr_possible_cpu_arch_ids(MachineState *machine) > { > int i; > const char *core_type; > - int spapr_max_cores = max_cpus / smp_threads; > - MachineClass *mc = MACHINE_GET_CLASS(machine); > > - if (!mc->has_hotpluggable_cpus) { > - spapr_max_cores = QEMU_ALIGN_UP(smp_cpus, smp_threads) / smp_threads; > - } > if (machine->possible_cpus) { > - assert(machine->possible_cpus->len == spapr_max_cores); > + assert(machine->possible_cpus->len == max_cpus); > return machine->possible_cpus; > } > > @@ -3820,16 +3813,16 @@ static const CPUArchIdList *spapr_possible_cpu_arch_ids(MachineState *machine) > } > > machine->possible_cpus = g_malloc0(sizeof(CPUArchIdList) + > - sizeof(CPUArchId) * spapr_max_cores); > - machine->possible_cpus->len = spapr_max_cores; > + sizeof(CPUArchId) * max_cpus); > + machine->possible_cpus->len = max_cpus; > for (i = 0; i < machine->possible_cpus->len; i++) { > - int core_id = i * smp_threads; > - > machine->possible_cpus->cpus[i].type = core_type; > machine->possible_cpus->cpus[i].vcpus_count = smp_threads; > - machine->possible_cpus->cpus[i].arch_id = core_id; > + machine->possible_cpus->cpus[i].arch_id = i; > machine->possible_cpus->cpus[i].props.has_core_id = true; > - machine->possible_cpus->cpus[i].props.core_id = core_id; > + machine->possible_cpus->cpus[i].props.core_id = i / smp_threads; > + machine->possible_cpus->cpus[i].props.has_thread_id = true; > + machine->possible_cpus->cpus[i].props.thread_id = i % smp_threads; > } > return machine->possible_cpus; > } -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson