xemu/hw/vfio
Keqian Zhu 758b96b61d vfio/migrate: Move switch of dirty tracking into vfio_memory_listener
For now the switch of vfio dirty page tracking is integrated into
@vfio_save_handler. The reason is that some PCI vendor driver may
start to track dirty base on _SAVING state of device, so if dirty
tracking is started before setting device state, vfio will report
full-dirty to QEMU.

However, the dirty bmap of all ramblocks are fully set when setup
ram saving, so it's not matter whether the device is in _SAVING
state when start vfio dirty tracking.

Moreover, this logic causes some problems [1]. The object of dirty
tracking is guest memory, but the object of @vfio_save_handler is
device state, which produces unnecessary coupling and conflicts:

1. Coupling: Their saving granule is different (perVM vs perDevice).
   vfio will enable dirty_page_tracking for each devices, actually
   once is enough.

2. Conflicts: The ram_save_setup() traverses all memory_listeners
   to execute their log_start() and log_sync() hooks to get the
   first round dirty bitmap, which is used by the bulk stage of
   ram saving. However, as vfio dirty tracking is not yet started,
   it can't get dirty bitmap from vfio. Then we give up the chance
   to handle vfio dirty page at bulk stage.

Move the switch of vfio dirty_page_tracking into vfio_memory_listener
can solve above problems. Besides, Do not require devices in SAVING
state for vfio_sync_dirty_bitmap().

[1] https://www.spinics.net/lists/kvm/msg229967.html

Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210309031913.11508-1-zhukeqian1@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-03-16 10:06:44 -06:00
..
amd-xgbe.c Include migration/vmstate.h less 2019-08-16 13:31:52 +02:00
ap.c Use OBJECT_DECLARE_SIMPLE_TYPE when possible 2020-09-18 14:12:32 -04:00
calxeda-xgmac.c Include migration/vmstate.h less 2019-08-16 13:31:52 +02:00
ccw.c vfio-ccw: Do not read region ret_code after write 2021-03-04 11:24:49 +01:00
common.c vfio/migrate: Move switch of dirty tracking into vfio_memory_listener 2021-03-16 10:06:44 -06:00
display.c ui: add an optional get_flags callback to GraphicHwOps 2021-02-04 15:58:54 +01:00
igd.c docs: Fix some typos (found by codespell) 2020-11-18 09:29:41 +01:00
Kconfig hw/vfio: Move the IGD quirk code to a separate file 2020-02-06 11:55:42 -07:00
meson.build vfio: Add migration region initialization and finalize function 2020-11-01 12:30:50 -07:00
migration.c vfio/migrate: Move switch of dirty tracking into vfio_memory_listener 2021-03-16 10:06:44 -06:00
pci-quirks.c hw/vfio/pci-quirks: Replace the word 'blacklist' 2021-03-16 10:06:44 -06:00
pci.c vfio: Avoid disabling and enabling vectors repeatedly in VFIO migration 2021-03-16 10:06:44 -06:00
pci.h hw/vfio/pci-quirks: Replace the word 'blacklist' 2021-03-16 10:06:44 -06:00
platform.c hw/vfio: Use lock guard macros 2020-11-01 12:30:52 -07:00
spapr.c vfio/spapr: Fix page size calculation 2020-04-07 08:55:10 +10:00
trace-events hw/vfio/pci-quirks: Replace the word 'blacklist' 2021-03-16 10:06:44 -06:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00