[RFC,V2,08/37] arm/virt: Init PMU at host for all possible vcpus

Commit Message

Salil Mehta Sept. 26, 2023, 10:04 a.m. UTC

PMU for all possible vCPUs must be initialized at the VM initialization time.
Refactor existing code to accomodate possible vCPUs. This also assumes that all
processor being used are identical.

Past discussion for reference:
Link: https://lists.gnu.org/archive/html/qemu-devel/2020-06/msg00131.html

Co-developed-by: Salil Mehta <[e-mail]>
Signed-off-by: Salil Mehta <[e-mail]>
Co-developed-by: Keqian Zhu <[e-mail]>
Signed-off-by: Keqian Zhu <[e-mail]>
Signed-off-by: Salil Mehta <[e-mail]>
---
 hw/arm/virt.c         | 12 ++++++++----
 include/hw/arm/virt.h |  1 +
 2 files changed, 9 insertions(+), 4 deletions(-)

Patch

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index a208b4e517..070c36054e 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1960,12 +1960,14 @@  static void finalize_gic_version(VirtMachineState *vms)
  */
 static void virt_cpu_post_init(VirtMachineState *vms, MemoryRegion *sysmem)
 {
+    CPUArchIdList *possible_cpus = vms->parent.possible_cpus;
     int max_cpus = MACHINE(vms)->smp.max_cpus;
-    bool aarch64, pmu, steal_time;
+    bool aarch64, steal_time;
     CPUState *cpu;
+    int n;
 
     aarch64 = object_property_get_bool(OBJECT(first_cpu), "aarch64", NULL);
-    pmu = object_property_get_bool(OBJECT(first_cpu), "pmu", NULL);
+    vms->pmu = object_property_get_bool(OBJECT(first_cpu), "pmu", NULL);
     steal_time = object_property_get_bool(OBJECT(first_cpu),
                                           "kvm-steal-time", NULL);
 
@@ -1992,8 +1994,10 @@  static void virt_cpu_post_init(VirtMachineState *vms, MemoryRegion *sysmem)
             memory_region_add_subregion(sysmem, pvtime_reg_base, pvtime);
         }
 
-        CPU_FOREACH(cpu) {
-            if (pmu) {
+        for (n = 0; n < possible_cpus->len; n++) {
+            cpu = qemu_get_possible_cpu(n);
+
+            if (vms->pmu) {
                 assert(arm_feature(&ARM_CPU(cpu)->env, ARM_FEATURE_PMU));
                 if (kvm_irqchip_in_kernel()) {
                     kvm_arm_pmu_set_irq(cpu, PPI(VIRTUAL_PMU_IRQ));
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 098c7917a4..fc0469c33f 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -164,6 +164,7 @@  struct VirtMachineState {
     bool ras;
     bool mte;
     bool dtb_randomness;
+    bool pmu;
     OnOffAuto acpi;
     VirtGICType gic_version;
     VirtIOMMUType iommu;