This keeps compatibility on machine-types pc-1.1 and lower, and prints a
warning in case the requested configuration won't get the correct
topology.
Changes v1 -> v2:
- Move code to cpu.c
- keep using cpu_index on *-user
- Use SMP.contiguous_apic_ids global property
- Prints warning in case the compatibility mode will expose incorrect
topology
Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
---
hw/pc_piix.c | 4 ++++
target-i386/cpu.c | 34 ++++++++++++++++++++++++++++++----
2 files changed, 34 insertions(+), 4 deletions(-)
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index 0c0096f..f073916 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -375,6 +375,10 @@ static QEMUMachine pc_machine_v1_2 = {
.driver = "qxl",\
.property = "vgamem_mb",\
.value = stringify(8),\
+ },{\
+ .driver = "SMP",\
+ .property = "contiguous_apic_ids",\
+ .value = "true",\
}
static QEMUMachine pc_machine_v1_1 = {
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 1703373..ea6c7a7 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -23,9 +23,11 @@
#include "cpu.h"
#include "kvm.h"
+#include "topology.h"
#ifndef CONFIG_USER_ONLY
-#include "sysemu.h"
+#include "hw/qdev.h"
+#include "cpus.h"
#endif
#include "qemu-option.h"
@@ -492,13 +494,37 @@ static x86_def_t builtin_x86_defs[] = {
},
};
+#ifdef CONFIG_USER_ONLY
unsigned int apic_id_for_cpu(int cpu_index)
{
- /* right now APIC ID == CPU index. this will eventually change to use
- * the CPU topology configuration properly
- */
+ /* *-user doesn't have any CPU topology settings, just use the CPU index */
return cpu_index;
}
+#else
+unsigned int apic_id_for_cpu(int cpu_index)
+{
+ const char *contig;
+ bool is_contiguous;
+ unsigned int correct_id;
+ static bool warned = false;
+
+ /* Global property SMP.contiguous_apic_ids=true will keep compatibility
+ * with the old (broken) behavior when calculating APIC IDs
+ */
+ contig = qemu_global_get("SMP", "contiguous_apic_ids");
+ is_contiguous = contig && !strcmp(contig, "true");
+ correct_id = topo_apicid_for_cpu(smp_cores, smp_threads, cpu_index);
+ if (is_contiguous) {
+ if (cpu_index != correct_id && !warned) {
+ fprintf(stderr, "warning: CPU topology in compatibility mode, it
will not match the requested topology\n");
+ warned = true;
+ }
+ return cpu_index;
+ } else {
+ return correct_id;
+ }
+}
+#endif
static int cpu_x86_fill_model_id(char *str)
{
--
1.7.11.2
