[PATCH] hw/arm/virt: Move common vCPU properties in a function

Salil Mehta via posted 1 patch 2 weeks, 6 days ago
hw/arm/virt.c         | 238 +++++++++++++++++++++++++-----------------
include/hw/arm/virt.h |   4 +
2 files changed, 147 insertions(+), 95 deletions(-)
[PATCH] hw/arm/virt: Move common vCPU properties in a function
Posted by Salil Mehta via 2 weeks, 6 days ago
Refactor vCPU properties code from the `machvirt_init()` main loop with
the following goals:

1. Enable code reuse in future patch sets.
2. Improve code readability.
3. Separate out the one-time initialization of (secure-)Tagged memory,
   handling potential failures early.

Note: This is a cosmetic change only; *no* functional changes are
      intended here.

Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
---
 hw/arm/virt.c         | 238 +++++++++++++++++++++++++-----------------
 include/hw/arm/virt.h |   4 +
 2 files changed, 147 insertions(+), 95 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 1a381e9a2b..a0d3bef875 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -2091,16 +2091,126 @@ static void virt_cpu_post_init(VirtMachineState *vms, MemoryRegion *sysmem)
     }
 }
 
+static void virt_cpu_set_properties(Object *cpuobj, Error **errp)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    MachineClass *mc = MACHINE_GET_CLASS(ms);
+    VirtMachineState *vms = VIRT_MACHINE(ms);
+    const CPUArchIdList *possible_cpus;
+    Error *local_err = NULL;
+    VirtMachineClass *vmc;
+
+    vmc = VIRT_MACHINE_GET_CLASS(ms);
+
+    possible_cpus = mc->possible_cpu_arch_ids(ms);
+    object_property_set_int(cpuobj, "mp-affinity",
+                            possible_cpus->cpus[CPU(cpuobj)->cpu_index].arch_id,
+                            NULL);
+
+    numa_cpu_pre_plug(&possible_cpus->cpus[CPU(cpuobj)->cpu_index],
+                      DEVICE(cpuobj), &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    if (!vms->secure) {
+        object_property_set_bool(cpuobj, "has_el3", false, NULL);
+    }
+
+    if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
+        object_property_set_bool(cpuobj, "has_el2", false, NULL);
+    }
+
+    if (vmc->kvm_no_adjvtime &&
+        object_property_find(cpuobj, "kvm-no-adjvtime")) {
+        object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL);
+    }
+
+    if (vmc->no_kvm_steal_time &&
+        object_property_find(cpuobj, "kvm-steal-time")) {
+        object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
+    }
+
+    if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
+        object_property_set_bool(cpuobj, "pmu", false, NULL);
+    }
+
+    if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
+        object_property_set_bool(cpuobj, "lpa2", false, NULL);
+    }
+
+    if (object_property_find(cpuobj, "reset-cbar")) {
+        object_property_set_int(cpuobj, "reset-cbar",
+                                vms->memmap[VIRT_CPUPERIPHS].base,
+                                &local_err);
+        if (local_err) {
+            goto out;
+        }
+    }
+
+    object_property_set_link(cpuobj, "memory", OBJECT(vms->sysmem), &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    if (vms->secure) {
+        object_property_set_link(cpuobj, "secure-memory",
+                                 OBJECT(vms->secure_sysmem), &local_err);
+        if (local_err) {
+            goto out;
+        }
+    }
+
+    if (vms->mte) {
+        if (tcg_enabled()) {
+            /*
+             * The property exists only if MemTag is supported.
+             * If it is, we must allocate the ram to back that up.
+             */
+            if (!object_property_find(cpuobj, "tag-memory")) {
+                error_report("MTE requested, but not supported "
+                             "by the guest CPU");
+                exit(1);
+            }
+
+            object_property_set_link(cpuobj, "tag-memory",
+                                     OBJECT(vms->tag_sysmem), &local_err);
+            if (local_err) {
+                goto out;
+            }
+
+            if (vms->secure) {
+                object_property_set_link(cpuobj, "secure-tag-memory",
+                                         OBJECT(vms->secure_tag_sysmem),
+                                         &local_err);
+                if (local_err) {
+                    goto out;
+                }
+            }
+        } else if (kvm_enabled()) {
+            kvm_arm_enable_mte(cpuobj, &local_err);
+            if (local_err) {
+                goto out;
+            }
+        }
+    }
+
+out:
+    if (local_err) {
+        error_propagate(errp, local_err);
+    }
+}
+
 static void machvirt_init(MachineState *machine)
 {
     VirtMachineState *vms = VIRT_MACHINE(machine);
     VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(machine);
     MachineClass *mc = MACHINE_GET_CLASS(machine);
     const CPUArchIdList *possible_cpus;
-    MemoryRegion *sysmem = get_system_memory();
+    MemoryRegion *secure_tag_sysmem = NULL;
     MemoryRegion *secure_sysmem = NULL;
     MemoryRegion *tag_sysmem = NULL;
-    MemoryRegion *secure_tag_sysmem = NULL;
+    MemoryRegion *sysmem;
     int n, virt_max_cpus;
     bool firmware_loaded;
     bool aarch64 = true;
@@ -2140,6 +2250,8 @@ static void machvirt_init(MachineState *machine)
      */
     finalize_gic_version(vms);
 
+    sysmem = vms->sysmem = get_system_memory();
+
     if (vms->secure) {
         /*
          * The Secure view of the world is the same as the NonSecure,
@@ -2147,7 +2259,7 @@ static void machvirt_init(MachineState *machine)
          * containing the system memory at low priority; any secure-only
          * devices go in at higher priority and take precedence.
          */
-        secure_sysmem = g_new(MemoryRegion, 1);
+        secure_sysmem = vms->secure_sysmem = g_new(MemoryRegion, 1);
         memory_region_init(secure_sysmem, OBJECT(machine), "secure-memory",
                            UINT64_MAX);
         memory_region_add_subregion_overlap(secure_sysmem, 0, sysmem, -1);
@@ -2220,6 +2332,33 @@ static void machvirt_init(MachineState *machine)
         exit(1);
     }
 
+    if (vms->mte && !kvm_enabled() && !tcg_enabled()) {
+        error_report("MTE requested, but not supported ");
+        exit(1);
+    }
+
+    if (vms->mte && kvm_enabled() && !kvm_arm_mte_supported()) {
+        error_report("MTE requested, but not supported by KVM");
+        exit(1);
+    }
+
+    if (vms->mte && tcg_enabled()) {
+        /* Create the memory region only once, but link to all cpus later */
+        tag_sysmem = vms->tag_sysmem = g_new(MemoryRegion, 1);
+        memory_region_init(tag_sysmem, OBJECT(machine),
+                           "tag-memory", UINT64_MAX / 32);
+
+        if (vms->secure) {
+            secure_tag_sysmem = vms->secure_tag_sysmem = g_new(MemoryRegion, 1);
+            memory_region_init(secure_tag_sysmem, OBJECT(machine),
+                               "secure-tag-memory", UINT64_MAX / 32);
+
+            /* As with ram, secure-tag takes precedence over tag.  */
+            memory_region_add_subregion_overlap(secure_tag_sysmem, 0,
+                                                tag_sysmem, -1);
+        }
+    }
+
     create_fdt(vms);
 
     assert(possible_cpus->len == max_cpus);
@@ -2232,104 +2371,13 @@ static void machvirt_init(MachineState *machine)
         }
 
         cpuobj = object_new(possible_cpus->cpus[n].type);
-        object_property_set_int(cpuobj, "mp-affinity",
-                                possible_cpus->cpus[n].arch_id, NULL);
 
         cs = CPU(cpuobj);
         cs->cpu_index = n;
 
-        numa_cpu_pre_plug(&possible_cpus->cpus[cs->cpu_index], DEVICE(cpuobj),
-                          &error_fatal);
-
         aarch64 &= object_property_get_bool(cpuobj, "aarch64", NULL);
 
-        if (!vms->secure) {
-            object_property_set_bool(cpuobj, "has_el3", false, NULL);
-        }
-
-        if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
-            object_property_set_bool(cpuobj, "has_el2", false, NULL);
-        }
-
-        if (vmc->kvm_no_adjvtime &&
-            object_property_find(cpuobj, "kvm-no-adjvtime")) {
-            object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL);
-        }
-
-        if (vmc->no_kvm_steal_time &&
-            object_property_find(cpuobj, "kvm-steal-time")) {
-            object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
-        }
-
-        if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
-            object_property_set_bool(cpuobj, "pmu", false, NULL);
-        }
-
-        if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
-            object_property_set_bool(cpuobj, "lpa2", false, NULL);
-        }
-
-        if (object_property_find(cpuobj, "reset-cbar")) {
-            object_property_set_int(cpuobj, "reset-cbar",
-                                    vms->memmap[VIRT_CPUPERIPHS].base,
-                                    &error_abort);
-        }
-
-        object_property_set_link(cpuobj, "memory", OBJECT(sysmem),
-                                 &error_abort);
-        if (vms->secure) {
-            object_property_set_link(cpuobj, "secure-memory",
-                                     OBJECT(secure_sysmem), &error_abort);
-        }
-
-        if (vms->mte) {
-            if (tcg_enabled()) {
-                /* Create the memory region only once, but link to all cpus. */
-                if (!tag_sysmem) {
-                    /*
-                     * The property exists only if MemTag is supported.
-                     * If it is, we must allocate the ram to back that up.
-                     */
-                    if (!object_property_find(cpuobj, "tag-memory")) {
-                        error_report("MTE requested, but not supported "
-                                     "by the guest CPU");
-                        exit(1);
-                    }
-
-                    tag_sysmem = g_new(MemoryRegion, 1);
-                    memory_region_init(tag_sysmem, OBJECT(machine),
-                                       "tag-memory", UINT64_MAX / 32);
-
-                    if (vms->secure) {
-                        secure_tag_sysmem = g_new(MemoryRegion, 1);
-                        memory_region_init(secure_tag_sysmem, OBJECT(machine),
-                                           "secure-tag-memory",
-                                           UINT64_MAX / 32);
-
-                        /* As with ram, secure-tag takes precedence over tag. */
-                        memory_region_add_subregion_overlap(secure_tag_sysmem,
-                                                            0, tag_sysmem, -1);
-                    }
-                }
-
-                object_property_set_link(cpuobj, "tag-memory",
-                                         OBJECT(tag_sysmem), &error_abort);
-                if (vms->secure) {
-                    object_property_set_link(cpuobj, "secure-tag-memory",
-                                             OBJECT(secure_tag_sysmem),
-                                             &error_abort);
-                }
-            } else if (kvm_enabled()) {
-                if (!kvm_arm_mte_supported()) {
-                    error_report("MTE requested, but not supported by KVM");
-                    exit(1);
-                }
-                kvm_arm_enable_mte(cpuobj, &error_abort);
-            } else {
-                    error_report("MTE requested, but not supported ");
-                    exit(1);
-            }
-        }
+        virt_cpu_set_properties(cpuobj, &error_abort);
 
         qdev_realize(DEVICE(cpuobj), NULL, &error_fatal);
         object_unref(cpuobj);
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index aca4f8061b..239f3678af 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -143,6 +143,10 @@ struct VirtMachineState {
     DeviceState *platform_bus_dev;
     FWCfgState *fw_cfg;
     PFlashCFI01 *flash[2];
+    MemoryRegion *sysmem;
+    MemoryRegion *secure_sysmem;
+    MemoryRegion *tag_sysmem;
+    MemoryRegion *secure_tag_sysmem;
     bool secure;
     bool highmem;
     bool highmem_compact;
-- 
2.34.1
Re: [PATCH] hw/arm/virt: Move common vCPU properties in a function
Posted by Gavin Shan 2 weeks, 4 days ago
On 11/4/24 1:22 AM, Salil Mehta wrote:
> Refactor vCPU properties code from the `machvirt_init()` main loop with
> the following goals:
> 
> 1. Enable code reuse in future patch sets.
> 2. Improve code readability.
> 3. Separate out the one-time initialization of (secure-)Tagged memory,
>     handling potential failures early.
> 
> Note: This is a cosmetic change only; *no* functional changes are
>        intended here.
> 
> Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
> ---
>   hw/arm/virt.c         | 238 +++++++++++++++++++++++++-----------------
>   include/hw/arm/virt.h |   4 +
>   2 files changed, 147 insertions(+), 95 deletions(-)
> 

With the following nitpicks addressed:

Reviewed-by: Gavin Shan <gshan@redhat.com>

> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 1a381e9a2b..a0d3bef875 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -2091,16 +2091,126 @@ static void virt_cpu_post_init(VirtMachineState *vms, MemoryRegion *sysmem)
>       }
>   }
>   
> +static void virt_cpu_set_properties(Object *cpuobj, Error **errp)
> +{
> +    MachineState *ms = MACHINE(qdev_get_machine());
> +    MachineClass *mc = MACHINE_GET_CLASS(ms);
> +    VirtMachineState *vms = VIRT_MACHINE(ms);
> +    const CPUArchIdList *possible_cpus;
> +    Error *local_err = NULL;
> +    VirtMachineClass *vmc;
> +
> +    vmc = VIRT_MACHINE_GET_CLASS(ms);
> +
> +    possible_cpus = mc->possible_cpu_arch_ids(ms);


virt_cpu_set_properties() is only called by machvirt_init() where MachineState
is passed in as parameter. So MachineState can be passed down as a parameter
instead of retriving it by qdev_get_machine(). Besides, the chunk of code can
be further compact.

static void virt_cpu_set_properties(MachineState *ms, Object *cpuobj, Error **errp)
{
     VirtMachineState *vms = VIRT_MACHINE(ms);
     MachineClass *mc = MACHINE_GET_CLASS(ms);
     VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(ms);
     const CPUArchIdList *possible_cpus = mc->possible_cpu_arch_ids(ms);
     Error *local_err = NULL;
       :

}


> +    object_property_set_int(cpuobj, "mp-affinity",
> +                            possible_cpus->cpus[CPU(cpuobj)->cpu_index].arch_id,
> +                            NULL);
> +
> +    numa_cpu_pre_plug(&possible_cpus->cpus[CPU(cpuobj)->cpu_index],
> +                      DEVICE(cpuobj), &local_err);
> +    if (local_err) {
> +        goto out;
> +    }
> +
> +    if (!vms->secure) {
> +        object_property_set_bool(cpuobj, "has_el3", false, NULL);
> +    }
> +
> +    if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
> +        object_property_set_bool(cpuobj, "has_el2", false, NULL);
> +    }
> +
> +    if (vmc->kvm_no_adjvtime &&
> +        object_property_find(cpuobj, "kvm-no-adjvtime")) {
> +        object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL);
> +    }
> +
> +    if (vmc->no_kvm_steal_time &&
> +        object_property_find(cpuobj, "kvm-steal-time")) {
> +        object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
> +    }
> +
> +    if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
> +        object_property_set_bool(cpuobj, "pmu", false, NULL);
> +    }
> +
> +    if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
> +        object_property_set_bool(cpuobj, "lpa2", false, NULL);
> +    }
> +
> +    if (object_property_find(cpuobj, "reset-cbar")) {
> +        object_property_set_int(cpuobj, "reset-cbar",
> +                                vms->memmap[VIRT_CPUPERIPHS].base,
> +                                &local_err);
> +        if (local_err) {
> +            goto out;
> +        }
> +    }
> +
> +    object_property_set_link(cpuobj, "memory", OBJECT(vms->sysmem), &local_err);
> +    if (local_err) {
> +        goto out;
> +    }
> +
> +    if (vms->secure) {
> +        object_property_set_link(cpuobj, "secure-memory",
> +                                 OBJECT(vms->secure_sysmem), &local_err);
> +        if (local_err) {
> +            goto out;
> +        }
> +    }
> +
> +    if (vms->mte) {
> +        if (tcg_enabled()) {
> +            /*
> +             * The property exists only if MemTag is supported.
> +             * If it is, we must allocate the ram to back that up.
> +             */
> +            if (!object_property_find(cpuobj, "tag-memory")) {
> +                error_report("MTE requested, but not supported "
> +                             "by the guest CPU");
> +                exit(1);
> +            }
> +
> +            object_property_set_link(cpuobj, "tag-memory",
> +                                     OBJECT(vms->tag_sysmem), &local_err);
> +            if (local_err) {
> +                goto out;
> +            }
> +
> +            if (vms->secure) {
> +                object_property_set_link(cpuobj, "secure-tag-memory",
> +                                         OBJECT(vms->secure_tag_sysmem),
> +                                         &local_err);
> +                if (local_err) {
> +                    goto out;
> +                }
> +            }
> +        } else if (kvm_enabled()) {
> +            kvm_arm_enable_mte(cpuobj, &local_err);
> +            if (local_err) {
> +                goto out;
> +            }
> +        }
> +    }
> +
> +out:
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +    }
> +}
> +
>   static void machvirt_init(MachineState *machine)
>   {
>       VirtMachineState *vms = VIRT_MACHINE(machine);
>       VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(machine);
>       MachineClass *mc = MACHINE_GET_CLASS(machine);
>       const CPUArchIdList *possible_cpus;
> -    MemoryRegion *sysmem = get_system_memory();
> +    MemoryRegion *secure_tag_sysmem = NULL;
>       MemoryRegion *secure_sysmem = NULL;
>       MemoryRegion *tag_sysmem = NULL;
> -    MemoryRegion *secure_tag_sysmem = NULL;
> +    MemoryRegion *sysmem;
>       int n, virt_max_cpus;
>       bool firmware_loaded;
>       bool aarch64 = true;

Unnecessary change caused after the defination of @secure_tag_sysmem is moved around. Also,
I personally prefer to keep the order to define @sysmem, @secure_sysmem, @tag_sysmem and
@secure_tag_system. So this chunk of code would be something like below:

     MemoryRegion *sysmem;
     MemoryRegion *secure_sysmem = NULL;
     MemoryRegion *tag_sysmem = NULL;
     MemoryRegion *secure_tag_sysmem = NULL;

> @@ -2140,6 +2250,8 @@ static void machvirt_init(MachineState *machine)
>        */
>       finalize_gic_version(vms);
>   
> +    sysmem = vms->sysmem = get_system_memory();
> +
>       if (vms->secure) {
>           /*
>            * The Secure view of the world is the same as the NonSecure,
> @@ -2147,7 +2259,7 @@ static void machvirt_init(MachineState *machine)
>            * containing the system memory at low priority; any secure-only
>            * devices go in at higher priority and take precedence.
>            */
> -        secure_sysmem = g_new(MemoryRegion, 1);
> +        secure_sysmem = vms->secure_sysmem = g_new(MemoryRegion, 1);
>           memory_region_init(secure_sysmem, OBJECT(machine), "secure-memory",
>                              UINT64_MAX);
>           memory_region_add_subregion_overlap(secure_sysmem, 0, sysmem, -1);
> @@ -2220,6 +2332,33 @@ static void machvirt_init(MachineState *machine)
>           exit(1);
>       }
>   
> +    if (vms->mte && !kvm_enabled() && !tcg_enabled()) {
> +        error_report("MTE requested, but not supported ");
> +        exit(1);
> +    }
> +
> +    if (vms->mte && kvm_enabled() && !kvm_arm_mte_supported()) {
> +        error_report("MTE requested, but not supported by KVM");
> +        exit(1);
> +    }
> +
> +    if (vms->mte && tcg_enabled()) {
> +        /* Create the memory region only once, but link to all cpus later */
> +        tag_sysmem = vms->tag_sysmem = g_new(MemoryRegion, 1);
> +        memory_region_init(tag_sysmem, OBJECT(machine),
> +                           "tag-memory", UINT64_MAX / 32);
> +
> +        if (vms->secure) {
> +            secure_tag_sysmem = vms->secure_tag_sysmem = g_new(MemoryRegion, 1);
> +            memory_region_init(secure_tag_sysmem, OBJECT(machine),
> +                               "secure-tag-memory", UINT64_MAX / 32);
> +
> +            /* As with ram, secure-tag takes precedence over tag.  */
> +            memory_region_add_subregion_overlap(secure_tag_sysmem, 0,
> +                                                tag_sysmem, -1);
> +        }
> +    }
> +
>       create_fdt(vms);
>   
>       assert(possible_cpus->len == max_cpus);
> @@ -2232,104 +2371,13 @@ static void machvirt_init(MachineState *machine)
>           }
>   
>           cpuobj = object_new(possible_cpus->cpus[n].type);
> -        object_property_set_int(cpuobj, "mp-affinity",
> -                                possible_cpus->cpus[n].arch_id, NULL);
>   
>           cs = CPU(cpuobj);
>           cs->cpu_index = n;
>   
> -        numa_cpu_pre_plug(&possible_cpus->cpus[cs->cpu_index], DEVICE(cpuobj),
> -                          &error_fatal);
> -
>           aarch64 &= object_property_get_bool(cpuobj, "aarch64", NULL);
>   
> -        if (!vms->secure) {
> -            object_property_set_bool(cpuobj, "has_el3", false, NULL);
> -        }
> -
> -        if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
> -            object_property_set_bool(cpuobj, "has_el2", false, NULL);
> -        }
> -
> -        if (vmc->kvm_no_adjvtime &&
> -            object_property_find(cpuobj, "kvm-no-adjvtime")) {
> -            object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL);
> -        }
> -
> -        if (vmc->no_kvm_steal_time &&
> -            object_property_find(cpuobj, "kvm-steal-time")) {
> -            object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
> -        }
> -
> -        if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
> -            object_property_set_bool(cpuobj, "pmu", false, NULL);
> -        }
> -
> -        if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
> -            object_property_set_bool(cpuobj, "lpa2", false, NULL);
> -        }
> -
> -        if (object_property_find(cpuobj, "reset-cbar")) {
> -            object_property_set_int(cpuobj, "reset-cbar",
> -                                    vms->memmap[VIRT_CPUPERIPHS].base,
> -                                    &error_abort);
> -        }
> -
> -        object_property_set_link(cpuobj, "memory", OBJECT(sysmem),
> -                                 &error_abort);
> -        if (vms->secure) {
> -            object_property_set_link(cpuobj, "secure-memory",
> -                                     OBJECT(secure_sysmem), &error_abort);
> -        }
> -
> -        if (vms->mte) {
> -            if (tcg_enabled()) {
> -                /* Create the memory region only once, but link to all cpus. */
> -                if (!tag_sysmem) {
> -                    /*
> -                     * The property exists only if MemTag is supported.
> -                     * If it is, we must allocate the ram to back that up.
> -                     */
> -                    if (!object_property_find(cpuobj, "tag-memory")) {
> -                        error_report("MTE requested, but not supported "
> -                                     "by the guest CPU");
> -                        exit(1);
> -                    }
> -
> -                    tag_sysmem = g_new(MemoryRegion, 1);
> -                    memory_region_init(tag_sysmem, OBJECT(machine),
> -                                       "tag-memory", UINT64_MAX / 32);
> -
> -                    if (vms->secure) {
> -                        secure_tag_sysmem = g_new(MemoryRegion, 1);
> -                        memory_region_init(secure_tag_sysmem, OBJECT(machine),
> -                                           "secure-tag-memory",
> -                                           UINT64_MAX / 32);
> -
> -                        /* As with ram, secure-tag takes precedence over tag. */
> -                        memory_region_add_subregion_overlap(secure_tag_sysmem,
> -                                                            0, tag_sysmem, -1);
> -                    }
> -                }
> -
> -                object_property_set_link(cpuobj, "tag-memory",
> -                                         OBJECT(tag_sysmem), &error_abort);
> -                if (vms->secure) {
> -                    object_property_set_link(cpuobj, "secure-tag-memory",
> -                                             OBJECT(secure_tag_sysmem),
> -                                             &error_abort);
> -                }
> -            } else if (kvm_enabled()) {
> -                if (!kvm_arm_mte_supported()) {
> -                    error_report("MTE requested, but not supported by KVM");
> -                    exit(1);
> -                }
> -                kvm_arm_enable_mte(cpuobj, &error_abort);
> -            } else {
> -                    error_report("MTE requested, but not supported ");
> -                    exit(1);
> -            }
> -        }
> +        virt_cpu_set_properties(cpuobj, &error_abort);
>   
>           qdev_realize(DEVICE(cpuobj), NULL, &error_fatal);
>           object_unref(cpuobj);
> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
> index aca4f8061b..239f3678af 100644
> --- a/include/hw/arm/virt.h
> +++ b/include/hw/arm/virt.h
> @@ -143,6 +143,10 @@ struct VirtMachineState {
>       DeviceState *platform_bus_dev;
>       FWCfgState *fw_cfg;
>       PFlashCFI01 *flash[2];
> +    MemoryRegion *sysmem;
> +    MemoryRegion *secure_sysmem;
> +    MemoryRegion *tag_sysmem;
> +    MemoryRegion *secure_tag_sysmem;
>       bool secure;
>       bool highmem;
>       bool highmem_compact;

Thanks,
Gavin
RE: [PATCH] hw/arm/virt: Move common vCPU properties in a function
Posted by Salil Mehta via 2 weeks, 3 days ago
Hi Gavin,

Thanks for the valuable  comments. I will address them but it looks peter has already
pulled ARM changes for this cycle?

Thanks
Salil.
>  From: Gavin Shan <gshan@redhat.com>
>  Sent: Tuesday, November 5, 2024 12:01 AM
>  To: Salil Mehta <salil.mehta@huawei.com>; qemu-devel@nongnu.org;
>  qemu-arm@nongnu.org; mst@redhat.com; richard.henderson@linaro.org;
>  peter.maydell@linaro.org
>  Cc: Jonathan Cameron <jonathan.cameron@huawei.com>;
>  alex.bennee@linaro.org; imammedo@redhat.com; pbonzini@redhat.com;
>  maz@kernel.org; will@kernel.org; oliver.upton@linux.dev; jean-
>  philippe@linaro.org; lpieralisi@kernel.org; david@redhat.com;
>  philmd@linaro.org; andrew.jones@linux.dev; eric.auger@redhat.com;
>  npiggin@gmail.com; harshpb@linux.ibm.com; linux@armlinux.org.uk;
>  darren@os.amperecomputing.com; ilkka@os.amperecomputing.com;
>  vishnu@os.amperecomputing.com; karl.heubaum@oracle.com;
>  miguel.luis@oracle.com; salil.mehta@opnsrc.net; zhukeqian
>  <zhukeqian1@huawei.com>; wangxiongfeng (C)
>  <wangxiongfeng2@huawei.com>; wangyanan (Y)
>  <wangyanan55@huawei.com>; jiakernel2@gmail.com;
>  maobibo@loongson.cn; lixianglai@loongson.cn; shahuang@redhat.com;
>  zhao1.liu@intel.com; Linuxarm <linuxarm@huawei.com>;
>  gustavo.romero@linaro.org
>  Subject: Re: [PATCH] hw/arm/virt: Move common vCPU properties in a
>  function
>  
>  On 11/4/24 1:22 AM, Salil Mehta wrote:
>  > Refactor vCPU properties code from the `machvirt_init()` main loop
>  > with the following goals:
>  >
>  > 1. Enable code reuse in future patch sets.
>  > 2. Improve code readability.
>  > 3. Separate out the one-time initialization of (secure-)Tagged memory,
>  >     handling potential failures early.
>  >
>  > Note: This is a cosmetic change only; *no* functional changes are
>  >        intended here.
>  >
>  > Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
>  > ---
>  >   hw/arm/virt.c         | 238 +++++++++++++++++++++++++-----------------
>  >   include/hw/arm/virt.h |   4 +
>  >   2 files changed, 147 insertions(+), 95 deletions(-)
>  >
>  
>  With the following nitpicks addressed:
>  
>  Reviewed-by: Gavin Shan <gshan@redhat.com>
>  
>  > diff --git a/hw/arm/virt.c b/hw/arm/virt.c index
>  > 1a381e9a2b..a0d3bef875 100644
>  > --- a/hw/arm/virt.c
>  > +++ b/hw/arm/virt.c
>  > @@ -2091,16 +2091,126 @@ static void
>  virt_cpu_post_init(VirtMachineState *vms, MemoryRegion *sysmem)
>  >       }
>  >   }
>  >
>  > +static void virt_cpu_set_properties(Object *cpuobj, Error **errp) {
>  > +    MachineState *ms = MACHINE(qdev_get_machine());
>  > +    MachineClass *mc = MACHINE_GET_CLASS(ms);
>  > +    VirtMachineState *vms = VIRT_MACHINE(ms);
>  > +    const CPUArchIdList *possible_cpus;
>  > +    Error *local_err = NULL;
>  > +    VirtMachineClass *vmc;
>  > +
>  > +    vmc = VIRT_MACHINE_GET_CLASS(ms);
>  > +
>  > +    possible_cpus = mc->possible_cpu_arch_ids(ms);
>  
>  
>  virt_cpu_set_properties() is only called by machvirt_init() where
>  MachineState is passed in as parameter. So MachineState can be passed
>  down as a parameter instead of retriving it by qdev_get_machine().
>  Besides, the chunk of code can be further compact.
>  
>  static void virt_cpu_set_properties(MachineState *ms, Object *cpuobj,
>  Error **errp) {
>       VirtMachineState *vms = VIRT_MACHINE(ms);
>       MachineClass *mc = MACHINE_GET_CLASS(ms);
>       VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(ms);
>       const CPUArchIdList *possible_cpus = mc->possible_cpu_arch_ids(ms);
>       Error *local_err = NULL;
>         :
>  
>  }
>  
>  
>  > +    object_property_set_int(cpuobj, "mp-affinity",
>  > +                            possible_cpus->cpus[CPU(cpuobj)->cpu_index].arch_id,
>  > +                            NULL);
>  > +
>  > +    numa_cpu_pre_plug(&possible_cpus->cpus[CPU(cpuobj)-
>  >cpu_index],
>  > +                      DEVICE(cpuobj), &local_err);
>  > +    if (local_err) {
>  > +        goto out;
>  > +    }
>  > +
>  > +    if (!vms->secure) {
>  > +        object_property_set_bool(cpuobj, "has_el3", false, NULL);
>  > +    }
>  > +
>  > +    if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
>  > +        object_property_set_bool(cpuobj, "has_el2", false, NULL);
>  > +    }
>  > +
>  > +    if (vmc->kvm_no_adjvtime &&
>  > +        object_property_find(cpuobj, "kvm-no-adjvtime")) {
>  > +        object_property_set_bool(cpuobj, "kvm-no-adjvtime", true, NULL);
>  > +    }
>  > +
>  > +    if (vmc->no_kvm_steal_time &&
>  > +        object_property_find(cpuobj, "kvm-steal-time")) {
>  > +        object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
>  > +    }
>  > +
>  > +    if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
>  > +        object_property_set_bool(cpuobj, "pmu", false, NULL);
>  > +    }
>  > +
>  > +    if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
>  > +        object_property_set_bool(cpuobj, "lpa2", false, NULL);
>  > +    }
>  > +
>  > +    if (object_property_find(cpuobj, "reset-cbar")) {
>  > +        object_property_set_int(cpuobj, "reset-cbar",
>  > +                                vms->memmap[VIRT_CPUPERIPHS].base,
>  > +                                &local_err);
>  > +        if (local_err) {
>  > +            goto out;
>  > +        }
>  > +    }
>  > +
>  > +    object_property_set_link(cpuobj, "memory", OBJECT(vms->sysmem),
>  &local_err);
>  > +    if (local_err) {
>  > +        goto out;
>  > +    }
>  > +
>  > +    if (vms->secure) {
>  > +        object_property_set_link(cpuobj, "secure-memory",
>  > +                                 OBJECT(vms->secure_sysmem), &local_err);
>  > +        if (local_err) {
>  > +            goto out;
>  > +        }
>  > +    }
>  > +
>  > +    if (vms->mte) {
>  > +        if (tcg_enabled()) {
>  > +            /*
>  > +             * The property exists only if MemTag is supported.
>  > +             * If it is, we must allocate the ram to back that up.
>  > +             */
>  > +            if (!object_property_find(cpuobj, "tag-memory")) {
>  > +                error_report("MTE requested, but not supported "
>  > +                             "by the guest CPU");
>  > +                exit(1);
>  > +            }
>  > +
>  > +            object_property_set_link(cpuobj, "tag-memory",
>  > +                                     OBJECT(vms->tag_sysmem), &local_err);
>  > +            if (local_err) {
>  > +                goto out;
>  > +            }
>  > +
>  > +            if (vms->secure) {
>  > +                object_property_set_link(cpuobj, "secure-tag-memory",
>  > +                                         OBJECT(vms->secure_tag_sysmem),
>  > +                                         &local_err);
>  > +                if (local_err) {
>  > +                    goto out;
>  > +                }
>  > +            }
>  > +        } else if (kvm_enabled()) {
>  > +            kvm_arm_enable_mte(cpuobj, &local_err);
>  > +            if (local_err) {
>  > +                goto out;
>  > +            }
>  > +        }
>  > +    }
>  > +
>  > +out:
>  > +    if (local_err) {
>  > +        error_propagate(errp, local_err);
>  > +    }
>  > +}
>  > +
>  >   static void machvirt_init(MachineState *machine)
>  >   {
>  >       VirtMachineState *vms = VIRT_MACHINE(machine);
>  >       VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(machine);
>  >       MachineClass *mc = MACHINE_GET_CLASS(machine);
>  >       const CPUArchIdList *possible_cpus;
>  > -    MemoryRegion *sysmem = get_system_memory();
>  > +    MemoryRegion *secure_tag_sysmem = NULL;
>  >       MemoryRegion *secure_sysmem = NULL;
>  >       MemoryRegion *tag_sysmem = NULL;
>  > -    MemoryRegion *secure_tag_sysmem = NULL;
>  > +    MemoryRegion *sysmem;
>  >       int n, virt_max_cpus;
>  >       bool firmware_loaded;
>  >       bool aarch64 = true;
>  
>  Unnecessary change caused after the defination of @secure_tag_sysmem
>  is moved around. Also, I personally prefer to keep the order to define
>  @sysmem, @secure_sysmem, @tag_sysmem and @secure_tag_system.
>  So this chunk of code would be something like below:
>  
>       MemoryRegion *sysmem;
>       MemoryRegion *secure_sysmem = NULL;
>       MemoryRegion *tag_sysmem = NULL;
>       MemoryRegion *secure_tag_sysmem = NULL;
>  
>  > @@ -2140,6 +2250,8 @@ static void machvirt_init(MachineState
>  *machine)
>  >        */
>  >       finalize_gic_version(vms);
>  >
>  > +    sysmem = vms->sysmem = get_system_memory();
>  > +
>  >       if (vms->secure) {
>  >           /*
>  >            * The Secure view of the world is the same as the
>  > NonSecure, @@ -2147,7 +2259,7 @@ static void
>  machvirt_init(MachineState *machine)
>  >            * containing the system memory at low priority; any secure-only
>  >            * devices go in at higher priority and take precedence.
>  >            */
>  > -        secure_sysmem = g_new(MemoryRegion, 1);
>  > +        secure_sysmem = vms->secure_sysmem = g_new(MemoryRegion,
>  1);
>  >           memory_region_init(secure_sysmem, OBJECT(machine), "secure-
>  memory",
>  >                              UINT64_MAX);
>  >           memory_region_add_subregion_overlap(secure_sysmem, 0,
>  > sysmem, -1); @@ -2220,6 +2332,33 @@ static void
>  machvirt_init(MachineState *machine)
>  >           exit(1);
>  >       }
>  >
>  > +    if (vms->mte && !kvm_enabled() && !tcg_enabled()) {
>  > +        error_report("MTE requested, but not supported ");
>  > +        exit(1);
>  > +    }
>  > +
>  > +    if (vms->mte && kvm_enabled() && !kvm_arm_mte_supported()) {
>  > +        error_report("MTE requested, but not supported by KVM");
>  > +        exit(1);
>  > +    }
>  > +
>  > +    if (vms->mte && tcg_enabled()) {
>  > +        /* Create the memory region only once, but link to all cpus later */
>  > +        tag_sysmem = vms->tag_sysmem = g_new(MemoryRegion, 1);
>  > +        memory_region_init(tag_sysmem, OBJECT(machine),
>  > +                           "tag-memory", UINT64_MAX / 32);
>  > +
>  > +        if (vms->secure) {
>  > +            secure_tag_sysmem = vms->secure_tag_sysmem =
>  g_new(MemoryRegion, 1);
>  > +            memory_region_init(secure_tag_sysmem, OBJECT(machine),
>  > +                               "secure-tag-memory", UINT64_MAX / 32);
>  > +
>  > +            /* As with ram, secure-tag takes precedence over tag.  */
>  > +            memory_region_add_subregion_overlap(secure_tag_sysmem, 0,
>  > +                                                tag_sysmem, -1);
>  > +        }
>  > +    }
>  > +
>  >       create_fdt(vms);
>  >
>  >       assert(possible_cpus->len == max_cpus); @@ -2232,104 +2371,13 @@
>  > static void machvirt_init(MachineState *machine)
>  >           }
>  >
>  >           cpuobj = object_new(possible_cpus->cpus[n].type);
>  > -        object_property_set_int(cpuobj, "mp-affinity",
>  > -                                possible_cpus->cpus[n].arch_id, NULL);
>  >
>  >           cs = CPU(cpuobj);
>  >           cs->cpu_index = n;
>  >
>  > -        numa_cpu_pre_plug(&possible_cpus->cpus[cs->cpu_index],
>  DEVICE(cpuobj),
>  > -                          &error_fatal);
>  > -
>  >           aarch64 &= object_property_get_bool(cpuobj, "aarch64",
>  > NULL);
>  >
>  > -        if (!vms->secure) {
>  > -            object_property_set_bool(cpuobj, "has_el3", false, NULL);
>  > -        }
>  > -
>  > -        if (!vms->virt && object_property_find(cpuobj, "has_el2")) {
>  > -            object_property_set_bool(cpuobj, "has_el2", false, NULL);
>  > -        }
>  > -
>  > -        if (vmc->kvm_no_adjvtime &&
>  > -            object_property_find(cpuobj, "kvm-no-adjvtime")) {
>  > -            object_property_set_bool(cpuobj, "kvm-no-adjvtime", true,
>  NULL);
>  > -        }
>  > -
>  > -        if (vmc->no_kvm_steal_time &&
>  > -            object_property_find(cpuobj, "kvm-steal-time")) {
>  > -            object_property_set_bool(cpuobj, "kvm-steal-time", false, NULL);
>  > -        }
>  > -
>  > -        if (vmc->no_pmu && object_property_find(cpuobj, "pmu")) {
>  > -            object_property_set_bool(cpuobj, "pmu", false, NULL);
>  > -        }
>  > -
>  > -        if (vmc->no_tcg_lpa2 && object_property_find(cpuobj, "lpa2")) {
>  > -            object_property_set_bool(cpuobj, "lpa2", false, NULL);
>  > -        }
>  > -
>  > -        if (object_property_find(cpuobj, "reset-cbar")) {
>  > -            object_property_set_int(cpuobj, "reset-cbar",
>  > -                                    vms->memmap[VIRT_CPUPERIPHS].base,
>  > -                                    &error_abort);
>  > -        }
>  > -
>  > -        object_property_set_link(cpuobj, "memory", OBJECT(sysmem),
>  > -                                 &error_abort);
>  > -        if (vms->secure) {
>  > -            object_property_set_link(cpuobj, "secure-memory",
>  > -                                     OBJECT(secure_sysmem), &error_abort);
>  > -        }
>  > -
>  > -        if (vms->mte) {
>  > -            if (tcg_enabled()) {
>  > -                /* Create the memory region only once, but link to all cpus. */
>  > -                if (!tag_sysmem) {
>  > -                    /*
>  > -                     * The property exists only if MemTag is supported.
>  > -                     * If it is, we must allocate the ram to back that up.
>  > -                     */
>  > -                    if (!object_property_find(cpuobj, "tag-memory")) {
>  > -                        error_report("MTE requested, but not supported "
>  > -                                     "by the guest CPU");
>  > -                        exit(1);
>  > -                    }
>  > -
>  > -                    tag_sysmem = g_new(MemoryRegion, 1);
>  > -                    memory_region_init(tag_sysmem, OBJECT(machine),
>  > -                                       "tag-memory", UINT64_MAX / 32);
>  > -
>  > -                    if (vms->secure) {
>  > -                        secure_tag_sysmem = g_new(MemoryRegion, 1);
>  > -                        memory_region_init(secure_tag_sysmem, OBJECT(machine),
>  > -                                           "secure-tag-memory",
>  > -                                           UINT64_MAX / 32);
>  > -
>  > -                        /* As with ram, secure-tag takes precedence over tag. */
>  > -
>  memory_region_add_subregion_overlap(secure_tag_sysmem,
>  > -                                                            0, tag_sysmem, -1);
>  > -                    }
>  > -                }
>  > -
>  > -                object_property_set_link(cpuobj, "tag-memory",
>  > -                                         OBJECT(tag_sysmem), &error_abort);
>  > -                if (vms->secure) {
>  > -                    object_property_set_link(cpuobj, "secure-tag-memory",
>  > -                                             OBJECT(secure_tag_sysmem),
>  > -                                             &error_abort);
>  > -                }
>  > -            } else if (kvm_enabled()) {
>  > -                if (!kvm_arm_mte_supported()) {
>  > -                    error_report("MTE requested, but not supported by KVM");
>  > -                    exit(1);
>  > -                }
>  > -                kvm_arm_enable_mte(cpuobj, &error_abort);
>  > -            } else {
>  > -                    error_report("MTE requested, but not supported ");
>  > -                    exit(1);
>  > -            }
>  > -        }
>  > +        virt_cpu_set_properties(cpuobj, &error_abort);
>  >
>  >           qdev_realize(DEVICE(cpuobj), NULL, &error_fatal);
>  >           object_unref(cpuobj);
>  > diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h index
>  > aca4f8061b..239f3678af 100644
>  > --- a/include/hw/arm/virt.h
>  > +++ b/include/hw/arm/virt.h
>  > @@ -143,6 +143,10 @@ struct VirtMachineState {
>  >       DeviceState *platform_bus_dev;
>  >       FWCfgState *fw_cfg;
>  >       PFlashCFI01 *flash[2];
>  > +    MemoryRegion *sysmem;
>  > +    MemoryRegion *secure_sysmem;
>  > +    MemoryRegion *tag_sysmem;
>  > +    MemoryRegion *secure_tag_sysmem;
>  >       bool secure;
>  >       bool highmem;
>  >       bool highmem_compact;
>  
>  Thanks,
>  Gavin
>