Commit Graph

96 Commits

Author SHA1 Message Date
Peter Xu
cc5ab87200 migration: Unify reset of last_rb on destination node when recover
When postcopy recover happens, we need to reset last_rb after each return of
postcopy_pause_fault_thread() because that means we just got the postcopy
migration continued.

Unify this reset to the place right before we want to kick the fault thread
again, when we get the command MIG_CMD_POSTCOPY_RESUME from source.

This is actually more than that - because the main thread on destination will
now be able to call migrate_send_rp_req_pages_pending() too, so the fault
thread is not the only user of last_rb now.  Move the reset earlier will allow
the first call to migrate_send_rp_req_pages_pending() to use the reset value
even if called from the main thread.

(NOTE: this is not a real fix to 0c26781c09 mentioned below, however it is just
 a mark that when picking up 0c26781c09 we'd better have this one too; the real
 fix will come later)

Fixes: 0c26781c09 ("migration: Sync requested pages after postcopy recovery")
Tested-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20201102153010.11979-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-11-02 18:25:39 +00:00
Peter Xu
8f8bfffcf1 migration: Maintain postcopy faulted addresses
Maintain a list of faulted addresses on the destination host for which we're
waiting on.  This is implemented using a GTree rather than a real list to make
sure even there're plenty of vCPUs/threads that are faulting, the lookup will
still be fast with O(log(N)) (because we'll do that after placing each page).
It should bring a slight overhead, but ideally that shouldn't be a big problem
simply because in most cases the requested page list will be short.

Actually we did similar things for postcopy blocktime measurements.  This patch
didn't use that simply because:

  (1) blocktime measurement is towards vcpu threads only, but here we need to
      record all faulted addresses, including main thread and external
      thread (like, DPDK via vhost-user).

  (2) blocktime measurement will require UFFD_FEATURE_THREAD_ID, but here we
      don't want to add that extra dependency on the kernel version since not
      necessary.  E.g., we don't need to know which thread faulted on which
      page, we also don't care about multiple threads faulting on the same
      page.  But we only care about what addresses are faulted so waiting for a
      page copying from src.

  (3) blocktime measurement is not enabled by default.  However we need this by
      default especially for postcopy recover.

Another thing to mention is that this patch introduced a new mutex to serialize
the receivedmap and the page_requested tree, however that serialization does
not cover other procedures like UFFDIO_COPY.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201021212721.440373-4-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Peter Xu
eef621c4e6 migration: Pass incoming state into qemu_ufd_copy_ioctl()
It'll be used in follow up patches to access more fields out of it.  Meanwhile
fetch the userfaultfd inside the function.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201021212721.440373-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Bihong Yu
395cb45009 migration: Add spaces around operator
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1603163448-27122-4-git-send-email-yubihong@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Peter Xu
2e2bce167e migration: Rework migrate_send_rp_req_pages() function
We duplicated the logic of maintaining the last_rb variable at both callers of
this function.  Pass *rb pointer into the function so that we can avoid
duplicating the logic.  Also, when we have the rb pointer, it's also easier to
remove the original 2nd & 4th parameters, because both of them (name of the
ramblock when needed, or the page size) can be fetched from the ramblock
pointer too.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20200908203022.341615-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-25 11:11:01 +01:00
Stefan Hajnoczi
d73415a315 qemu/atomic.h: rename atomic_ to qatomic_
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:

  $ CC=clang CXX=clang++ ./configure ... && make
  ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)

Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.

This patch was generated using:

  $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
    sort -u >/tmp/changed_identifiers
  $ for identifier in $(</tmp/changed_identifiers); do
        sed -i "s%\<$identifier\>%q$identifier%g" \
            $(git grep -I -l "\<$identifier\>")
    done

I manually fixed line-wrap issues and misaligned rST tables.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
2020-09-23 16:07:44 +01:00
zhaolichang
3a4452d896 migration/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the migration folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200917075029.313-3-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:36:32 +02:00
Peter Maydell
c8eaf81fd2 virtio,acpi: features, fixes, cleanups.
vdpa support
 virtio-mem support
 a handy script for disassembling acpi tables
 misc fixes and cleanups
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,acpi: features, fixes, cleanups.

vdpa support
virtio-mem support
a handy script for disassembling acpi tables
misc fixes and cleanups

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 07 Jul 2020 13:00:35 BST
# gpg:                using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg:                issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (41 commits)
  vhost-vdpa: introduce vhost-vdpa net client
  vhost-vdpa: introduce vhost-vdpa backend
  vhost_net: introduce set_config & get_config
  vhost: implement vhost_force_iommu method
  vhost: introduce new VhostOps vhost_force_iommu
  vhost: implement vhost_vq_get_addr method
  vhost: introduce new VhostOps vhost_vq_get_addr
  vhost: implement vhost_dev_start method
  vhost: introduce new VhostOps vhost_dev_start
  vhost: check the existence of vhost_set_iotlb_callback
  virtio-pci: implement queue_enabled method
  virtio-bus: introduce queue_enabled method
  vhost_net: use the function qemu_get_peer
  net: introduce qemu_get_peer
  MAINTAINERS: add VT-d entry
  docs: vhost-user: add Virtio status protocol feature
  tests/acpi: remove stale allowed tables
  numa: Auto-enable NUMA when any memory devices are possible
  virtio-mem: Exclude unplugged memory during migration
  virtio-mem: Add trace events
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	hw/arm/virt.c
#	hw/virtio/trace-events
2020-07-07 17:37:44 +01:00
Dr. David Alan Gilbert
617a32f529 migration: postcopy take proper error return
This function returns a boolean success and we're returning -1;
lets just use the 'out' error path.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: 58b7c17e22 ("Disable mlock around incoming postcopy")
Buglink: https://bugs.launchpad.net/qemu/+bug/1885720
Message-Id: <20200701093557.130096-1-dgilbert@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-03 16:23:05 +01:00
David Hildenbrand
06df2e692a virtio-balloon: Rip out qemu_balloon_inhibit()
The only remaining special case is postcopy. It cannot handle
concurrent discards yet, which would result in requesting already sent
pages from the source. Special-case it in virtio-balloon instead.

Introduce migration_in_incoming_postcopy(), to find out if incoming
postcopy is active.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-7-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-07-02 05:54:59 -04:00
Wei Yang
038adc2f58 core: replace getpagesize() with qemu_real_host_page_size
There are three page size in qemu:

  real host page size
  host page size
  target page size

All of them have dedicate variable to represent. For the last two, we
use the same form in the whole qemu project, while for the first one we
use two forms: qemu_real_host_page_size and getpagesize().

qemu_real_host_page_size is defined to be a replacement of
getpagesize(), so let it serve the role.

[Note] Not fully tested for some arch or device.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191013021145.16011-3-richardw.yang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-26 15:38:06 +02:00
Wei Yang
2a7eb14844 migration/postcopy: rename postcopy_ram_enable_notify to postcopy_ram_incoming_setup
Function postcopy_ram_incoming_setup and postcopy_ram_incoming_cleanup
is a pair. Rename to make it clear for audience.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20191010011316.31363-2-richardw.yang@linux.intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:59:58 +01:00
Wei Yang
2d49bacda0 migration/postcopy: postpone setting PostcopyState to END
There are two places to call function postcopy_ram_incoming_cleanup()

    postcopy_ram_listen_thread on migration success
    loadvm_postcopy_handle_listen one setup failure

On success, the vm will never accept another migration. On failure,
PostcopyState is transited from LISTENING to END and would be checked in
qemu_loadvm_state_main(). If PostcopyState is RUNNING, migration would
be paused and retried.

Currently PostcopyState is set to END in function
postcopy_ram_incoming_cleanup(). With above analysis, we can take this
step out and postpone this till the end of listen thread to indicate the
listen thread is done.

This is a preparation patch for later cleanup.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191006000249.29926-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixed up in merge to the 1 parameter postcopy_state_set
2019-10-11 14:57:22 +01:00
Wei Yang
da1725d3f9 migration/postcopy: fix typo in mark_postcopy_blocktime_begin's comment
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191005220517.24029-3-richardw.yang@linux.intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:31:08 +01:00
Wei Yang
6629890d55 migration/postcopy: map large zero page in postcopy_ram_incoming_setup()
postcopy_ram_incoming_setup() and postcopy_ram_incoming_cleanup() are
counterpart. It is reasonable to map/unmap large zero page in these two
functions respectively.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191005135021.21721-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:28:49 +01:00
Wei Yang
3414322a83 migration/postcopy: allocate tmp_page in setup stage
During migration, a tmp page is allocated so that we could place a whole
host page during postcopy.

Currently the page is allocated during load stage, this is a little bit
late. And more important, if we failed to allocate it, the error is not
checked properly. Even it is NULL, we would still use it.

This patch moves the allocation to setup stage and if failed error
message would be printed and caller would notice it.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:28:19 +01:00
Peter Maydell
95a9457fd4 Header cleanup patches for 2019-08-13
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Merge remote-tracking branch 'remotes/armbru/tags/pull-include-2019-08-13-v2' into staging

Header cleanup patches for 2019-08-13

# gpg: Signature made Fri 16 Aug 2019 12:39:12 BST
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-include-2019-08-13-v2: (29 commits)
  sysemu: Split sysemu/runstate.h off sysemu/sysemu.h
  sysemu: Move the VMChangeStateEntry typedef to qemu/typedefs.h
  Include sysemu/sysemu.h a lot less
  Clean up inclusion of sysemu/sysemu.h
  numa: Move remaining NUMA declarations from sysemu.h to numa.h
  Include sysemu/hostmem.h less
  numa: Don't include hw/boards.h into sysemu/numa.h
  Include hw/boards.h a bit less
  Include hw/qdev-properties.h less
  Include qemu/main-loop.h less
  Include qemu/queue.h slightly less
  Include hw/hw.h exactly where needed
  Include qom/object.h slightly less
  Include exec/memory.h slightly less
  Include migration/vmstate.h less
  migration: Move the VMStateDescription typedef to typedefs.h
  Clean up inclusion of exec/cpu-common.h
  Include hw/irq.h a lot less
  typedefs: Separate incomplete types and function types
  ide: Include hw/ide/internal a bit less outside hw/ide/
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-08-16 14:53:43 +01:00
Markus Armbruster
d484205210 Include exec/memory.h slightly less
Drop unnecessary inclusions from headers.  Downgrade a few more to
exec/hwaddr.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-17-armbru@redhat.com>
2019-08-16 13:31:52 +02:00
Wei Yang
810cf2bbd4 migration/postcopy: make PostcopyDiscardState a static variable
In postcopy-ram.c, we provide three functions to discard certain
RAMBlock range:

  * postcopy_discard_send_init()
  * postcopy_discard_send_range()
  * postcopy_discard_send_finish()

Currently, we allocate/deallocate PostcopyDiscardState for each RAMBlock
on sending discard information to destination. This is not necessary and
the same data area could be reused for each RAMBlock.

This patch defines PostcopyDiscardState a static variable. By doing so:

  1) avoid memory allocation and deallocation to the system
  2) avoid potential failure of memory allocation
  3) hide some details for their users

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>

Message-Id: <20190724010721.2146-1-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Like Xu
5cc8767d05 general: Replace global smp variables with smp machine properties
Basically, the context could get the MachineState reference via call
chains or unrecommended qdev_get_machine() in !CONFIG_USER_ONLY mode.

A local variable of the same name would be introduced in the declaration
phase out of less effort OR replace it on the spot if it's only used
once in the context. No semantic changes.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190518205428.90532-4-like.xu@linux.intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-07-05 17:07:36 -03:00
Yury Kotov
fbd162e629 migration: Add an ability to ignore shared RAM blocks
If ignore-shared capability is set then skip shared RAMBlocks during the
RAM migration.
Also, move qemu_ram_foreach_migratable_block (and rename) to the
migration code, because it requires access to the migration capabilities.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-4-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:17 +00:00
Yury Kotov
754cb9c0eb exec: Change RAMBlockIterFunc definition
Currently, qemu_ram_foreach_* calls RAMBlockIterFunc with many
block-specific arguments. But often iter func needs RAMBlock*.
This refactoring is needed for fast access to RAMBlock flags from
qemu_ram_foreach_block's callback. The only way to achieve this now
is to call qemu_ram_block_from_host (which also enumerates blocks).

So, this patch reduces complexity of
qemu_ram_foreach_block() -> cb() -> qemu_ram_block_from_host()
from O(n^2) to O(n).

Fix RAMBlockIterFunc definition and add some functions to read
RAMBlock* fields witch were passed.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-2-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:17 +00:00
Fei Li
91b02dc750 migration: add more error handling for postcopy_ram_enable_notify
Call postcopy_ram_incoming_cleanup() to do the cleanup when
postcopy_ram_enable_notify fails. Besides, report the error
message when qemu_ram_foreach_migratable_block() fails.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190113140849.38339-5-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23 15:02:07 +00:00
Ilya Maximets
55d0fe8254 migration: Stop postcopy fault thread before notifying
POSTCOPY_NOTIFY_INBOUND_END handlers will remove userfault fds
from the postcopy_remote_fds array which could be still in
use by the fault thread. Let's stop the thread before
notification to avoid possible accessing wrong memory.

Fixes: 46343570c0 ("vhost+postcopy: Wire up POSTCOPY_END notify")
Cc: qemu-stable@nongnu.org
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
Message-Id: <20181008160536.6332-2-i.maximets@samsung.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-10-11 19:58:26 +01:00
Peter Maydell
17182bb47f VFIO fixes 2018-08-23
- Fix coverity reported issue with use of realpath (Alex Williamson)
 
  - Cleanup file descriptor in error path (Alex Williamson)
 
  - Fix postcopy use of new balloon inhibitor (Alex Williamson)
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Merge remote-tracking branch 'remotes/awilliam/tags/vfio-fixes-20180823.1' into staging

VFIO fixes 2018-08-23

 - Fix coverity reported issue with use of realpath (Alex Williamson)

 - Cleanup file descriptor in error path (Alex Williamson)

 - Fix postcopy use of new balloon inhibitor (Alex Williamson)

# gpg: Signature made Thu 23 Aug 2018 17:46:41 BST
# gpg:                using RSA key 239B9B6E3BB08B22
# gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>"
# gpg:                 aka "Alex Williamson <alex@shazbot.org>"
# gpg:                 aka "Alex Williamson <alwillia@redhat.com>"
# gpg:                 aka "Alex Williamson <alex.l.williamson@gmail.com>"
# Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B  8A90 239B 9B6E 3BB0 8B22

* remotes/awilliam/tags/vfio-fixes-20180823.1:
  postcopy: Synchronize usage of the balloon inhibitor
  vfio/pci: Fix failure to close file descriptor on error
  vfio/pci: Handle subsystem realpath() returning NULL

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-08-25 10:59:06 +01:00
Alex Williamson
154304cd6e postcopy: Synchronize usage of the balloon inhibitor
While the qemu_balloon_inhibit() interface appears rather general purpose,
postcopy uses it in a last-caller-wins approach with no guarantee of balanced
inhibits and de-inhibits.  Wrap postcopy's usage of the inhibitor to give it
one vote overall, using the same last-caller-wins approach as previously
implemented at the balloon level.

Fixes: 01ccbec7bd ("balloon: Allow multiple inhibit users")
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-08-23 10:45:58 -06:00
Lidong Chen
74637e6f08 migration: implement bi-directional RDMA QIOChannel
This patch implements bi-directional RDMA QIOChannel. Because different
threads may access RDMAQIOChannel currently, this patch use RCU to protect it.

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:12:26 +02:00
David Hildenbrand
c136180c90 postcopy: drop ram_pages parameter from postcopy_ram_incoming_init()
Not needed. Don't expose last_ram_page().

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180620202736.21399-1-david@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-27 13:28:31 +02:00
Cédric Le Goater
b895de5027 migration: discard non-migratable RAMBlocks
On the POWER9 processor, the XIVE interrupt controller can control
interrupt sources using MMIO to trigger events, to EOI or to turn off
the sources. Priority management and interrupt acknowledgment is also
controlled by MMIO in the presenter sub-engine.

These MMIO regions are exposed to guests in QEMU with a set of 'ram
device' memory mappings, similarly to VFIO, and the VMAs are populated
dynamically with the appropriate pages using a fault handler.

But, these regions are an issue for migration. We need to discard the
associated RAMBlocks from the RAM state on the source VM and let the
destination VM rebuild the memory mappings on the new host in the
post_load() operation just before resuming the system.

To achieve this goal, the following introduces a new RAMBlock flag
RAM_MIGRATABLE which is updated in the vmstate_register_ram() and
vmstate_unregister_ram() routines. This flag is then used by the
migration to identify RAMBlocks to discard on the source. Some checks
are also performed on the destination to make sure nothing invalid was
sent.

This change impacts the boston, malta and jazz mips boards for which
migration compatibility is broken.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-04 05:46:15 +02:00
Peter Xu
3a7804c306 migration: allow fault thread to pause
Allows the fault thread to stop handling page faults temporarily. When
network failure happened (and if we expect a recovery afterwards), we
should not allow the fault thread to continue sending things to source,
instead, it should halt for a while until the connection is rebuilt.

When the dest main thread noticed the failure, it kicks the fault thread
to switch to pause state.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-7-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Alexey Perevalov
65ace06045 migration: add postcopy total blocktime into query-migrate
Postcopy total blocktime is available on destination side only.
But query-migrate was possible only for source. This patch
adds ability to call query-migrate on destination.
To be able to see postcopy blocktime, need to request postcopy-blocktime
capability.

The query-migrate command will show following sample result:
{"return":
    "postcopy-vcpu-blocktime": [115, 100],
    "status": "completed",
    "postcopy-blocktime": 100
}}

postcopy_vcpu_blocktime contains list, where the first item is the first
vCPU in QEMU.

This patch has a drawback, it combines states of incoming and
outgoing migration. Ongoing migration state will overwrite incoming
state. Looks like better to separate query-migrate for incoming and
outgoing migration or add parameter to indicate type of migration.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1521742647-25550-7-git-send-email-a.perevalov@samsung.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:02:17 +01:00
Alexey Perevalov
575b0b332e migration: calculate vCPU blocktime on dst side
This patch provides blocktime calculation per vCPU,
as a summary and as a overlapped value for all vCPUs.

This approach was suggested by Peter Xu, as an improvements of
previous approch where QEMU kept tree with faulted page address and cpus bitmask
in it. Now QEMU is keeping array with faulted page address as value and vCPU
as index. It helps to find proper vCPU at UFFD_COPY time. Also it keeps
list for blocktime per vCPU (could be traced with page_fault_addr)

Blocktime will not calculated if postcopy_blocktime field of
MigrationIncomingState wasn't initialized.

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1521742647-25550-4-git-send-email-a.perevalov@samsung.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:02:13 +01:00
Alexey Perevalov
2a4c42f18c migration: add postcopy blocktime ctx into MigrationIncomingState
This patch adds request to kernel space for UFFD_FEATURE_THREAD_ID, in
case this feature is provided by kernel.

PostcopyBlocktimeContext is encapsulated inside postcopy-ram.c,
due to it being a postcopy-only feature.
Also it defines PostcopyBlocktimeContext's instance live time.
Information from PostcopyBlocktimeContext instance will be provided
much after postcopy migration end, instance of PostcopyBlocktimeContext
will live till QEMU exit, but part of it (vcpu_addr,
page_fault_vcpu_time) used only during calculation, will be released
when postcopy ended or failed.

To enable postcopy blocktime calculation on destination, need to
request proper compatibility (Patch for documentation will be at the
tail of the patch set).

As an example following command enable that capability, assume QEMU was
started with
-chardev socket,id=charmonitor,path=/var/lib/migrate-vm-monitor.sock
option to control it

[root@host]#printf "{\"execute\" : \"qmp_capabilities\"}\r\n \
{\"execute\": \"migrate-set-capabilities\" , \"arguments\":   {
\"capabilities\": [ { \"capability\": \"postcopy-blocktime\", \"state\":
true } ] } }" | nc -U /var/lib/migrate-vm-monitor.sock

Or just with HMP
(qemu) migrate_set_capability postcopy-blocktime on

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1521742647-25550-3-git-send-email-a.perevalov@samsung.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:02:12 +01:00
Marc-André Lureau
fc6008f37a migration: fix pfd leak
Fix leak spotted by ASAN:

Direct leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x7fe1abb80a38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38)
    #1 0x7fe1aaf1bf75 in g_malloc0 ../glib/gmem.c:124
    #2 0x7fe1aaf1c249 in g_malloc0_n ../glib/gmem.c:355
    #3 0x55f4841cfaa9 in postcopy_ram_fault_thread /home/elmarco/src/qemu/migration/postcopy-ram.c:596
    #4 0x55f48479447b in qemu_thread_start /home/elmarco/src/qemu/util/qemu-thread-posix.c:504
    #5 0x7fe1a043550a in start_thread (/lib64/libpthread.so.0+0x750a)

Regression introduced with commit 00fa4fc85b.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180321113644.21899-1-marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-29 14:53:16 +01:00
Dr. David Alan Gilbert
29d8fa7f73 postcopy: Allow shared memory
Now that we have the mechanisms in here, allow shared memory in a
postcopy.

Note that QEMU can't tell who all the users of shared regions are
and thus can't tell whether all the users of the shared regions
have appropriate support for postcopy.  Those devices that explicitly
support shared memory (e.g. vhost-user) must check, but it doesn't
stop weirder configurations causing problems.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert
46343570c0 vhost+postcopy: Wire up POSTCOPY_END notify
Wire up a call to VHOST_USER_POSTCOPY_END message to the vhost clients
right before we ask the listener thread to shutdown.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert
dedfb4b21a vhost+postcopy: Call wakeups
Cause the vhost-user client to be woken up whenever:
  a) We place a page in postcopy mode
  b) We get a fault and the page has already been received

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert
d488b349a3 postcopy: postcopy_notify_shared_wake
Add a hook to allow a client userfaultfd to be 'woken'
when a page arrives, and a walker that calls that
hook for relevant clients given a RAMBlock and offset.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:37 +02:00
Dr. David Alan Gilbert
5efc356403 postcopy: helper for waking shared
Provide a helper to send a 'wake' request on a userfaultfd for
a shared process.
The address in the clients address space is specified together
with the RAMBlock it was resolved to.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:35 +02:00
Michael S. Tsirkin
c188c53927 postcopy-ram: add a stub for postcopy_request_shared_page
This fixes the build on systems without userfaultfd.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 16:40:10 +02:00
Dr. David Alan Gilbert
096bf4c852 vhost+postcopy: Helper to send requests to source for shared pages
Provide a helper to be used by shared waker functions to request
shared pages from the source.
The last_rb pointer is moved into the incoming state since this
helper can update it as well as the main fault thread function.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:29 +02:00
Dr. David Alan Gilbert
00fa4fc85b postcopy: Allow registering of fd handler
Allow other userfaultfd's to be registered into the fault thread
so that handlers for shared memory can get responses.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:28 +02:00
Dr. David Alan Gilbert
1693c64c27 postcopy: Add notifier chain
Add a notifier chain for postcopy with a 'reason' flag
and an opportunity for a notifier member to return an error.

Call it when enabling postcopy.

This will initially used to enable devices to declare they're unable
to postcopy and later to notify of devices of stages within postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:27 +02:00
Dr. David Alan Gilbert
2ce16640b4 postcopy: use UFFDIO_ZEROPAGE only when available
Use a flag on the RAMBlock to state whether it has the
UFFDIO_ZEROPAGE capability, use it when it's available.

This allows the use of postcopy on tmpfs as well as hugepage
backed files.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:27 +02:00
Peter Xu
9ab7ef9b66 migration: provide postcopy_fault_thread_notify()
A general helper to notify the fault thread.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-4-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:36:02 +00:00
Peter Xu
64f615fe34 migration: reuse mis->userfault_quit_fd
It was only used for quitting the page fault thread before. Let it be
something more useful - now we can use it to notify a "wake" for the
page fault thread (for any reason), and it only means "quit" if the
fault_thread_quit is set.

Since we changed what it does, renaming it to userfault_event_fd.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:35:45 +00:00
Peter Maydell
ee86981bda migration: Revert postcopy-blocktime commit set
This reverts commits
ca6011c migration: add postcopy total blocktime into query-migrate
5f32dc8 migration: add blocktime calculation into migration-test
2f7dae9 migration: postcopy_blocktime documentation
3be98be migration: calculate vCPU blocktime on dst side
01a87f0 migration: add postcopy blocktime ctx into MigrationIncomingState
31bf06a migration: introduce postcopy-blocktime capability

as they don't build on ppc32 due to trying to do atomic accesses
on types that are larger than the host pointer type.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-01-23 10:08:05 +00:00
Alexey Perevalov
ca6011c232 migration: add postcopy total blocktime into query-migrate
Postcopy total blocktime is available on destination side only.
But query-migrate was possible only for source. This patch
adds ability to call query-migrate on destination.
To be able to see postcopy blocktime, need to request postcopy-blocktime
capability.

The query-migrate command will show following sample result:
{"return":
    "postcopy-vcpu-blocktime": [115, 100],
    "status": "completed",
    "postcopy-blocktime": 100
}}

postcopy_vcpu_blocktime contains list, where the first item is the first
vCPU in QEMU.

This patch has a drawback, it combines states of incoming and
outgoing migration. Ongoing migration state will overwrite incoming
state. Looks like better to separate query-migrate for incoming and
outgoing migration or add parameter to indicate type of migration.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-01-15 12:48:04 +01:00
Alexey Perevalov
3be98be4e9 migration: calculate vCPU blocktime on dst side
This patch provides blocktime calculation per vCPU,
as a summary and as a overlapped value for all vCPUs.

This approach was suggested by Peter Xu, as an improvements of
previous approch where QEMU kept tree with faulted page address and cpus bitmask
in it. Now QEMU is keeping array with faulted page address as value and vCPU
as index. It helps to find proper vCPU at UFFD_COPY time. Also it keeps
list for blocktime per vCPU (could be traced with page_fault_addr)

Blocktime will not calculated if postcopy_blocktime field of
MigrationIncomingState wasn't initialized.

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-01-15 12:48:01 +01:00
Alexey Perevalov
01a87f0bd3 migration: add postcopy blocktime ctx into MigrationIncomingState
This patch adds request to kernel space for UFFD_FEATURE_THREAD_ID, in
case this feature is provided by kernel.

PostcopyBlocktimeContext is encapsulated inside postcopy-ram.c,
due to it being a postcopy-only feature.
Also it defines PostcopyBlocktimeContext's instance live time.
Information from PostcopyBlocktimeContext instance will be provided
much after postcopy migration end, instance of PostcopyBlocktimeContext
will live till QEMU exit, but part of it (vcpu_addr,
page_fault_vcpu_time) used only during calculation, will be released
when postcopy ended or failed.

To enable postcopy blocktime calculation on destination, need to
request proper compatibility (Patch for documentation will be at the
tail of the patch set).

As an example following command enable that capability, assume QEMU was
started with
-chardev socket,id=charmonitor,path=/var/lib/migrate-vm-monitor.sock
option to control it

[root@host]#printf "{\"execute\" : \"qmp_capabilities\"}\r\n \
{\"execute\": \"migrate-set-capabilities\" , \"arguments\":   {
\"capabilities\": [ { \"capability\": \"postcopy-blocktime\", \"state\":
true } ] } }" | nc -U /var/lib/migrate-vm-monitor.sock

Or just with HMP
(qemu) migrate_set_capability postcopy-blocktime on

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-01-15 12:48:00 +01:00