qemu/arm-virt-Init-PMU-at-host-for-all-possible-vcpus.patch

From c375e6fdc49f7d3d0232786e4cfd8b792379107c Mon Sep 17 00:00:00 2001
From: Salil Mehta <salil.mehta@huawei.com>
Date: Wed, 6 May 2020 14:12:34 +0100
Subject: [PATCH] arm/virt: Init PMU at host for all possible vcpus

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 <salil.mehta@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Co-developed-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 hw/arm/virt.c         | 12 ++++++++----
 include/hw/arm/virt.h |  1 +
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 08ba255317..78ed3c4ba8 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -2055,12 +2055,14 @@ 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);
 
@@ -2087,8 +2089,10 @@ 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, VIRTUAL_PMU_IRQ);
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index a6977bade5..c2fde0522c 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -155,6 +155,7 @@ struct VirtMachineState {
     bool ras;
     bool mte;
     bool dtb_randomness;
+    bool pmu;
     OnOffAuto acpi;
     VirtGICType gic_version;
     VirtIOMMUType iommu;
-- 
2.27.0