Re: [Qemu-devel] [PATCH 00/39] Delay destruction of memory regions to instance_finalize

[Anthony Liguori <anthony@codemonkey.ws>]

Paolo Bonzini <pbonzini@redhat.com> writes:

> QOM splits the destruction of a device in two phases:
>
> - unrealize, also known as "exit" from qdev times, should isolate
>   the device from the guest.  After unrealize returns, the guest
>   should not be able to issue new requests.
>
> - instance_finalize will reclaim the memory.  This is only called
>   after all requests terminate and drop the references on the
>   device.

Does it make sense to QOM-ify the memory regions?  If they were QOM
objects, they could be added as children and then the reaping would be
handled automatically.

Could be a follow up.

Regards,

Anthony Liguori

>
> This is important even now, but overlooked.  It will become much
> more important for devices that will be able to access memory
> out of the big QEMU lock.
>
> This series changes all PCI devices (the sole to support hotplug
> _and_ use MemoryRegions) to do memory_region_del_subregion at
> unrealize time, and memory_region_destroy at instance_finalize
> time.
>
> This is mostly a PCI patch, and independent from the others,
> so I believe it should go through mst's tree.
>
> Paolo
>
>
> Paolo Bonzini (39):
>   scsi: keep device alive while it has requests
>   dma: keep a device alive while it has SGLists
>   pci: split exit and finalize
>   ac97: use instance_finalize instead of exit
>   es1370: use instance_finalize instead of exit
>   hda: use instance_finalize instead of exit
>   serial: use instance_finalize instead of exit
>   tpci200: use instance_finalize instead of exit
>   pci-assign: use instance_finalize instead of exit
>   ahci: use instance_finalize instead of exit
>   msix: split msix_free from msix_uninit
>   cmd646: use instance_finalize instead of exit
>   ide/piix: use instance_finalize instead of exit
>   ide/via: use instance_finalize instead of exit
>   ivshmem: use instance_finalize instead of exit
>   pci-testdev: use instance_finalize instead of exit
>   vfio: use instance_finalize instead of exit
>   e1000: use instance_finalize instead of exit
>   eepro100: use instance_finalize instead of exit
>   ne2000: use instance_finalize instead of exit
>   pcnet: use instance_finalize instead of exit
>   rtl8139: use instance_finalize instead of exit
>   vmxnet3: use instance_finalize instead of exit
>   shpc: use instance_finalize instead of exit
>   pci_bridge: split pci_bridge_exitfn from pci_bridge_free
>   pcie_aer: pcie_aer_exit really frees stuff
>   pci_bridge: use instance_finalize instead of exit
>   ioh4320: use instance_finalize instead of exit
>   xio3130-downstream: use instance_finalize instead of exit
>   xio3130-upstream: use instance_finalize instead of exit
>   pcie: do not recreate mmcfg I/O region, use an alias instead
>   esp: use instance_finalize instead of exit
>   lsi: use instance_finalize instead of exit
>   pvscsi: use instance_finalize instead of exit
>   usb-uhci: use instance_finalize instead of exit
>   virtio-pci: use instance_finalize instead of exit
>   wdt_i6300esb: use instance_finalize instead of exit
>   xen_pt: use instance_finalize instead of exit
>   tpm: move add/del_subregion to realize/unrealize
>
>  dma-helpers.c                      |  6 ++++-
>  hw/audio/ac97.c                    |  5 ++--
>  hw/audio/es1370.c                  |  5 ++--
>  hw/audio/intel-hda.c               |  8 ++++++
>  hw/char/serial-pci.c               | 24 ++++++++++++++++++
>  hw/char/tpci200.c                  |  5 ++--
>  hw/i386/kvm/pci-assign.c           |  8 ++++++
>  hw/ide/ahci.c                      |  5 ++--
>  hw/ide/ahci.h                      |  2 +-
>  hw/ide/cmd646.c                    |  5 ++--
>  hw/ide/ich.c                       | 13 +++++++---
>  hw/ide/macio.c                     |  4 +--
>  hw/ide/piix.c                      |  8 +++---
>  hw/ide/via.c                       |  5 ++--
>  hw/misc/ivshmem.c                  | 10 +++++++-
>  hw/misc/pci-testdev.c              |  5 ++--
>  hw/misc/vfio.c                     | 52 +++++++++++++++++++++++++++++++++++---
>  hw/net/e1000.c                     |  5 ++--
>  hw/net/eepro100.c                  |  5 ++--
>  hw/net/ne2000.c                    |  5 ++--
>  hw/net/pcnet-pci.c                 |  5 ++--
>  hw/net/rtl8139.c                   |  5 ++--
>  hw/net/vmxnet3.c                   | 14 ++++++++--
>  hw/pci-bridge/i82801b11.c          |  1 +
>  hw/pci-bridge/ioh3420.c            | 11 +++++++-
>  hw/pci-bridge/pci_bridge_dev.c     | 14 +++++++++-
>  hw/pci-bridge/xio3130_downstream.c | 11 +++++++-
>  hw/pci-bridge/xio3130_upstream.c   | 11 +++++++-
>  hw/pci/msix.c                      | 26 ++++++++++++++-----
>  hw/pci/pci.c                       | 15 ++++++++---
>  hw/pci/pci_bridge.c                |  5 ++++
>  hw/pci/pcie_aer.c                  |  3 ++-
>  hw/pci/pcie_host.c                 | 22 ++++++++++++----
>  hw/pci/shpc.c                      |  8 +++++-
>  hw/scsi/esp-pci.c                  |  5 ++--
>  hw/scsi/lsi53c895a.c               |  5 ++--
>  hw/scsi/megasas.c                  |  4 +--
>  hw/scsi/scsi-bus.c                 |  4 +++
>  hw/scsi/virtio-scsi.c              | 10 +++++---
>  hw/scsi/vmw_pvscsi.c               | 12 ++++++++-
>  hw/tpm/tpm_tis.c                   | 14 +++++++---
>  hw/usb/hcd-ehci.c                  |  4 +--
>  hw/usb/hcd-uhci.c                  |  5 ++--
>  hw/virtio/virtio-pci.c             | 10 +++++++-
>  hw/watchdog/wdt_i6300esb.c         |  5 ++--
>  hw/xen/xen_pt.c                    | 10 ++++++++
>  hw/xen/xen_pt_config_init.c        |  3 ---
>  hw/xen/xen_pt_msi.c                |  8 +++++-
>  include/hw/pci/msix.h              |  1 +
>  include/hw/pci/pci.h               |  2 +-
>  include/hw/pci/pci_bridge.h        |  1 +
>  include/hw/pci/pcie_aer.h          |  2 +-
>  include/hw/pci/pcie_host.h         |  1 +
>  include/hw/pci/shpc.h              |  1 +
>  include/sysemu/dma.h               |  4 ++-
>  55 files changed, 355 insertions(+), 92 deletions(-)
>
> -- 
> 1.8.1.4