Add 'kvm' corelens module.

Show information about all the VMs and VCPUs of each VM.

Orabug: 37357370
Signed-off-by: Siddhi Katage <[email protected]>

drgn_tools/kvm.py

@@ -0,0 +1,219 @@
+# Copyright (c) 2024, Oracle and/or its affiliates.
+# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+import argparse
+import enum
+from typing import Iterable
+from typing import Iterator
+
+from drgn import cast
+from drgn import Object
+from drgn import Program
+from drgn.helpers.linux.list import list_for_each_entry
+from drgn.helpers.linux.pid import find_task
+from drgn.helpers.linux.sched import task_state_to_char
+from drgn.helpers.linux.xarray import xa_for_each
+
+from drgn_tools.corelens import CorelensModule
+from drgn_tools.table import print_table
+from drgn_tools.util import has_member
+
+
+class KvmVcpuState(enum.Enum):
+    """
+    Defined in include/uapi/linux/kvm.h, with prefix KVM_MP_STATE_
+    """
+
+    RUNNABLE = 0
+    UNINITIALIZED = 1
+    INIT_RECEIVED = 2
+    HALTED = 3
+    SIPI_RECEIVED = 4
+    STOPPED = 5
+    CHECK_STOP = 6
+    OPERATING = 7
+    LOAD = 8
+
+
+def for_each_vm(prog: Program) -> Iterable[Object]:
+    """
+    Iterates over all ``struct kvm *
+    """
+    try:
+        yield from list_for_each_entry(
+            "struct kvm", prog["vm_list"].address_of_(), "vm_list"
+        )
+    except KeyError:
+        print("No VMs running")
+
+
+def for_each_vcpu(vm: Object) -> Iterator[Object]:
+    if has_member(vm, "vcpus"):
+        vcpu_iterator = iter(vm.vcpus)
+    else:
+        vcpu_iterator = (
+            cast("struct kvm_vcpu *", e)
+            for _, e in xa_for_each(vm.vcpu_array.address_of_())
+        )
+    for struct_vcpu in vcpu_iterator:
+        if struct_vcpu.value_() == 0:
+            break
+        yield struct_vcpu
+
+
+def print_vm_list(prog: Program) -> None:
+    """
+    Print information for all the VMs
+    """
+    vm_list = for_each_vm(prog)
+
+    print(" =============<< VM LIST >>=================")
+    print("\n")
+    rows = [
+        [
+            "KVM",
+            "ONL",
+            "CRT",
+            "MEMSLOT_0",
+            "MEMSLOT_1",
+            "VCPUS",
+            "KVM_ARCH",
+            "KVM_STAT",
+            "PID",
+            "TASK",
+            "CPU",
+            "ST",
+        ]
+    ]
+
+    for vm in vm_list:
+        kvm_addr = hex(vm.value_())
+        pid = vm.userspace_pid.value_()
+        task = find_task(prog, pid)
+        if has_member(task, "cpu"):
+            cpu = task.cpu.value_()
+        else:
+            cpu = task.recent_used_cpu.value_()
+
+        if has_member(vm, "vcpus"):
+            vcpu = hex(vm.vcpus.address_of_())
+        else:
+            vcpu = hex(vm.vcpu_array.address_of_())
+
+        rows.append(
+            [
+                kvm_addr,
+                vm.online_vcpus.counter.value_(),
+                vm.created_vcpus.value_(),
+                hex(vm.memslots[0].value_()),
+                hex(vm.memslots[1].value_()),
+                vcpu,
+                hex(vm.arch.address_of_()),
+                hex(vm.stat.address_of_()),
+                pid,
+                hex(task.value_()),
+                cpu,
+                task_state_to_char(task),
+            ]
+        )
+    print_table(rows)
+
+
+def print_vcpu_list(prog: Program) -> None:
+    """
+    Print information for all the vcpus of each VM
+    """
+    vm_list = for_each_vm(prog)
+
+    print(" =============<< VCPU LIST >>=================")
+    print("\n")
+    rows = [
+        [
+            "KVM",
+            "VCPU",
+            "ID",
+            "IDX",
+            "ARCH",
+            "STAT",
+            "STAT_ID",
+            "STATE",
+            "CPU",
+            "TASK",
+        ]
+    ]
+
+    for vm in vm_list:
+        for vcpu in for_each_vcpu(vm):
+            cpu = vcpu.value_()
+            id = vcpu.vcpu_id.value_()
+
+            if has_member(vcpu, "vcpu_idx"):
+                idx = vcpu.vcpu_idx.value_()
+            else:
+                # The UEK5 does not have kvm_vcpu.vcpu_idx structure member. Print None instead.
+                idx = None
+            arch = hex(vcpu.arch.address_of_())
+            stat = hex(vcpu.stat.address_of_())
+            if has_member(vcpu, "stats_id"):
+                stat_id = vcpu.stats_id.string_().decode("utf-8")
+            else:
+                # The UEK5 does not have kvm_vcpu.stats_id structure member. Print None instead.
+                stat_id = None
+            state = vcpu.arch.mp_state.value_()
+            cpu = vcpu.cpu.value_()
+            if has_member(vcpu, "wait"):
+                task = hex(vcpu.wait.task.value_())
+            else:
+                # The UEK5 does not have kvm_vcpu.wait structure member. Print None instead.
+                task = None
+            rows.append(
+                [
+                    hex(vm.value_()),
+                    cpu,
+                    id,
+                    idx,
+                    arch,
+                    stat,
+                    stat_id,
+                    KvmVcpuState(state).name,
+                    cpu,
+                    str(task),
+                ]
+            )
+
+    print_table(rows)
+
+
+class KvmUtil(CorelensModule):
+    """
+    Show all the VM related info from KVM host side
+    """
+
+    name = "kvm"
+
+    default_args = [
+        [
+            "--vms",
+            "--vcpu",
+        ]
+    ]
+
+    def add_args(self, parser: argparse.ArgumentParser) -> None:
+        parser.add_argument(
+            "--vms",
+            dest="list_vm",
+            action="store_true",
+            help="show all VM info",
+        )
+        parser.add_argument(
+            "--vcpu",
+            dest="vcpu_list",
+            action="store_true",
+            help="show all vcpu info",
+        )
+
+    def run(self, prog: Program, args: argparse.Namespace) -> None:
+        if args.list_vm:
+            print_vm_list(prog)
+        if args.vcpu_list:
+            print_vcpu_list(prog)
+        return

tests/test_kvm.py

@@ -0,0 +1,8 @@
+# Copyright (c) 2024, Oracle and/or its affiliates.
+# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+from drgn_tools import kvm
+
+
+def test_kvmutil(prog):
+    kvm.print_vm_list(prog)
+    kvm.print_vcpu_list(prog)