[PATCH 00/15] Replace current_machine by qdev_get_machine() - Philippe Mathieu-Daudé

From: "Philippe Mathieu-Daudé" <philmd@redhat.com>
To: qemu-devel@nongnu.org
Cc: "Marcelo Tosatti" <mtosatti@redhat.com>,
	"Peter Maydell" <peter.maydell@linaro.org>,
	qemu-arm@nongnu.org, "Eduardo Habkost" <ehabkost@redhat.com>,
	"Juan Quintela" <quintela@redhat.com>,
	kvm@vger.kernel.org, "Paolo Bonzini" <pbonzini@redhat.com>,
	"Marcel Apfelbaum" <marcel.apfelbaum@gmail.com>,
	"Alistair Francis" <alistair.francis@wdc.com>,
	qemu-ppc@nongnu.org,
	"Dr. David Alan Gilbert" <dgilbert@redhat.com>,
	"Richard Henderson" <rth@twiddle.net>,
	"David Gibson" <david@gibson.dropbear.id.au>,
	"Philippe Mathieu-Daudé" <philmd@redhat.com>
Subject: [PATCH 00/15] Replace current_machine by qdev_get_machine()
Date: Thu,  9 Jan 2020 16:21:18 +0100	[thread overview]
Message-ID: <20200109152133.23649-1-philmd@redhat.com> (raw)

Blurb from previous question [1]:

  "hw/boards.h" declare current_machine, and vl.c defines it:

    current_machine = MACHINE(object_new_with_class(OBJECT_CLASS(machine_class)));
    object_property_add_child(object_get_root(), "machine",
                              OBJECT(current_machine), &error_abort);

  The bigger user of 'current_machine' is the accel/KVM code.

  Recently in a0628599f..cc7d44c2e0 "Replace global smp variables
  with machine smp properties" we started to use MACHINE(qdev_get_machine()).
  Following a0628599f..cc7d44c2e0, a5e0b33119 use 'current_machine' again.

  qdev_get_machine() resolves the machine in the QOM composition tree.

Paolo answered [2]:

> I would always use MACHINE(qdev_get_machine()), espeecially outside
> vl.c.  Ideally, current_machine would be static within vl.c or even
> unused outside the object_property_add_child() that you quote above.

Let's remove the global current_machine.

I am still confused by this comment:

  /* qdev_get_machine() can return something that's not TYPE_MACHINE
   * if this is one of the user-only emulators; in that case there's
   * no need to check the ignore_memory_transaction_failures board flag.
   */

[1] https://www.mail-archive.com/qemu-devel@nongnu.org/msg669475.html
[2] https://www.mail-archive.com/qemu-devel@nongnu.org/msg669493.html

Philippe Mathieu-Daudé (15):
  target/arm/kvm: Use CPUState::kvm_state in kvm_arm_pmu_supported()
  hw/ppc/spapr_rtas: Use local MachineState variable
  hw/ppc/spapr_rtas: Access MachineState via SpaprMachineState argument
  hw/ppc/spapr_rtas: Restrict variables scope to single switch case
  device-hotplug: Replace current_machine by qdev_get_machine()
  migration/savevm: Replace current_machine by qdev_get_machine()
  hw/core/machine-qmp-cmds: Replace current_machine by
    qdev_get_machine()
  target/arm/monitor: Replace current_machine by qdev_get_machine()
  device_tree: Replace current_machine by qdev_get_machine()
  memory: Replace current_machine by qdev_get_machine()
  exec: Replace current_machine by qdev_get_machine()
  accel: Introduce the current_accel() method
  accel: Replace current_machine->accelerator by current_accel() method
  accel/accel: Replace current_machine by qdev_get_machine()
  vl: Make current_machine a local variable

 include/hw/boards.h        |  2 --
 include/sysemu/accel.h     |  2 ++
 accel/accel.c              |  7 +++++++
 accel/kvm/kvm-all.c        |  4 ++--
 accel/tcg/tcg-all.c        |  2 +-
 device-hotplug.c           |  2 +-
 device_tree.c              |  4 +++-
 exec.c                     | 10 ++++++----
 hw/core/machine-qmp-cmds.c |  4 ++--
 hw/ppc/spapr_rtas.c        |  6 +++---
 memory.c                   |  6 ++++--
 migration/savevm.c         | 10 +++++-----
 target/arm/kvm.c           |  4 +---
 target/arm/kvm64.c         |  4 ++--
 target/arm/monitor.c       |  3 ++-
 target/i386/kvm.c          |  2 +-
 target/ppc/kvm.c           |  2 +-
 vl.c                       |  6 +++---
 18 files changed, 46 insertions(+), 34 deletions(-)

-- 
2.21.1