[Qemu-devel] [PATCH RFC 08/16] hw/core/machine: set cpu global nr_cores, nr_threads in pre_init

[Andrew Jones <drjones@redhat.com>]

CPUState nr_cores and nr_threads are properties so we can set
them using the GlobalProperty API. Doing this in machine pre_init
allows us to easily propagate the values from the machine properties
to all cpus. An excellent bonus of this is that we can now remove
the references to the cpu topology globals smp_cores,smp_threads
from cpus.c.

Signed-off-by: Andrew Jones <drjones@redhat.com>
---
 cpus.c            |  2 --
 hw/core/machine.c | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/cpus.c b/cpus.c
index 326742f445eef..36d8faa0091c8 100644
--- a/cpus.c
+++ b/cpus.c
@@ -1427,8 +1427,6 @@ static void qemu_dummy_start_vcpu(CPUState *cpu)
 
 void qemu_init_vcpu(CPUState *cpu)
 {
-    cpu->nr_cores = smp_cores;
-    cpu->nr_threads = smp_threads;
     cpu->stopped = true;
 
     if (!cpu->as) {
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 75c5a1fdd7de1..5427924d4c911 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -511,9 +511,22 @@ static void machine_set_smp_parameters(MachineState *ms)
     ms->cpus    = cpus;
 }
 
+#define NR_CPUS_STRLEN sizeof(stringify(MAX_CPUMASK_BITS))
+
 static void machine_pre_init(MachineState *ms)
 {
     MachineClass *mc = MACHINE_CLASS(object_get_class(OBJECT(ms)));
+    static char nr_cores[NR_CPUS_STRLEN], nr_threads[NR_CPUS_STRLEN];
+    static GlobalProperty cpu_nr_cores = {
+        .driver   = "cpu",
+        .property = "nr-cores",
+        .value    = nr_cores,
+    };
+    static GlobalProperty cpu_nr_threads = {
+        .driver   = "cpu",
+        .property = "nr-threads",
+        .value    = nr_threads,
+    };
 
     machine_set_smp_parameters(ms);
     smp_cores   = ms->cores;
@@ -529,6 +542,11 @@ static void machine_pre_init(MachineState *ms)
         exit(1);
     }
 
+    snprintf(nr_cores, NR_CPUS_STRLEN, "%d", ms->cores);
+    snprintf(nr_threads, NR_CPUS_STRLEN, "%d", ms->threads);
+    qdev_prop_register_global(&cpu_nr_cores);
+    qdev_prop_register_global(&cpu_nr_threads);
+
     if (ms->cpus > 1) {
         Error *blocker = NULL;
         error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED, "smp");
-- 
2.4.11