Commit Graph

659 Commits

Author SHA1 Message Date
Juan Quintela
b013b5d1f3 migration: Make precopy_bytes atomic
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2023-04-24 11:28:58 +02:00
Juan Quintela
4291823694 migration: Make dirty_sync_missed_zero_copy atomic
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2023-04-24 11:28:57 +02:00
Juan Quintela
cf671116fa migration: Make multifd_bytes atomic
In the spirit of:

commit 394d323bc3451e4d07f13341cb8817fac8dfbadd
Author: Peter Xu <peterx@redhat.com>
Date:   Tue Oct 11 17:55:51 2022 -0400

    migration: Use atomic ops properly for page accountings

Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-04-24 11:28:57 +02:00
Juan Quintela
abce5fa16d migration: Merge ram_counters and ram_atomic_counters
Using MgrationStats as type for ram_counters mean that we didn't have
to re-declare each value in another struct. The need of atomic
counters have make us to create MigrationAtomicStats for this atomic
counters.

Create RAMStats type which is a merge of MigrationStats and
MigrationAtomicStats removing unused members.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

---

Fix typos found by David Edmondson
2023-04-24 11:28:56 +02:00
Peter Xu
06064a6715 migration: Recover behavior of preempt channel creation for pre-7.2
In 8.0 devel window we reworked preempt channel creation, so that there'll
be no race condition when the migration channel and preempt channel got
established in the wrong order in commit 5655aab079.

However no one noticed that the change will also be not compatible with
older qemus, majorly 7.1/7.2 versions where preempt mode started to be
supported.

Leverage the same pre-7.2 flag introduced in the previous patch to recover
the behavior hopefully before 8.0 releases, so we don't break migration
when we migrate from 8.0 to older qemu binaries.

Fixes: 5655aab079 ("migration: Postpone postcopy preempt channel to be after main")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-04-12 21:44:56 +02:00
Peter Xu
6621883f93 migration: Fix potential race on postcopy_qemufile_src
postcopy_qemufile_src object should be owned by one thread, either the main
thread (e.g. when at the beginning, or at the end of migration), or by the
return path thread (when during a preempt enabled postcopy migration).  If
that's not the case the access to the object might be racy.

postcopy_preempt_shutdown_file() can be potentially racy, because it's
called at the end phase of migration on the main thread, however during
which the return path thread hasn't yet been recycled; the recycle happens
in await_return_path_close_on_source() which is after this point.

It means, logically it's posslbe the main thread and the return path thread
are both operating on the same qemufile.  While I don't think qemufile is
thread safe at all.

postcopy_preempt_shutdown_file() used to be needed because that's where we
send EOS to dest so that dest can safely shutdown the preempt thread.

To avoid the possible race, remove this only place that a race can happen.
Instead we figure out another way to safely close the preempt thread on
dest.

The core idea during postcopy on deciding "when to stop" is that dest will
send a postcopy SHUT message to src, telling src that all data is there.
Hence to shut the dest preempt thread maybe better to do it directly on
dest node.

This patch proposed such a way that we change postcopy_prio_thread_created
into PreemptThreadStatus, so that we kick the preempt thread on dest qemu
by a sequence of:

  mis->preempt_thread_status = PREEMPT_THREAD_QUIT;
  qemu_file_shutdown(mis->postcopy_qemufile_dst);

While here shutdown() is probably so far the easiest way to kick preempt
thread from a blocked qemu_get_be64().  Then it reads preempt_thread_status
to make sure it's not a network failure but a willingness to quit the
thread.

We could have avoided that extra status but just rely on migration status.
The problem is postcopy_ram_incoming_cleanup() is just called early enough
so we're still during POSTCOPY_ACTIVE no matter what.. So just make it
simple to have the status introduced.

One flag x-preempt-pre-7-2 is added to keep old pre-7.2 behaviors of
postcopy preempt.

Fixes: 9358982744 ("migration: Send requested page directly in rp-return thread")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-04-12 21:44:38 +02:00
Juan Quintela
24beea4efe migration: Rename res_{postcopy,precopy}_only
Once that res_compatible is removed, they don't make sense anymore.
We remove the _only preffix.  And to make things clearer we rename
them to must_precopy and can_postcopy.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-15 20:04:30 +01:00
Juan Quintela
24f254ed79 migration: Remove unused res_compatible
Nothing assigns to it after previous commit.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-15 20:04:30 +01:00
Leonardo Bras
cfc3bcf373 migration/multifd: Move load_cleanup inside incoming_state_destroy
Currently running migration_incoming_state_destroy() without first running
multifd_load_cleanup() will cause a yank error:

qemu-system-x86_64: ../util/yank.c:107: yank_unregister_instance:
Assertion `QLIST_EMPTY(&entry->yankfns)' failed.
(core dumped)

The above error happens in the target host, when multifd is being used
for precopy, and then postcopy is triggered and the migration finishes.
This will crash the VM in the target host.

To avoid that, move multifd_load_cleanup() inside
migration_incoming_state_destroy(), so that the load cleanup becomes part
of the incoming state destroying process.

Running multifd_load_cleanup() twice can become an issue, though, but the
only scenario it could be ran twice is on process_incoming_migration_bh().
So removing this extra call is necessary.

On the other hand, this multifd_load_cleanup() call happens way before the
migration_incoming_state_destroy() and having this happening before
dirty_bitmap_mig_before_vm_start() and vm_start() may be a need.

So introduce a new function multifd_load_shutdown() that will mainly stop
all multifd threads and close their QIOChannels. Then use this function
instead of multifd_load_cleanup() to make sure nothing else is received
before dirty_bitmap_mig_before_vm_start().

Fixes: b5eea99ec2 ("migration: Add yank feature")
Reported-by: Li Xiaohui <xiaohli@redhat.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-13 03:45:40 +01:00
Leonardo Bras
e5bac1f525 migration/multifd: Change multifd_load_cleanup() signature and usage
Since it's introduction in commit f986c3d256 ("migration: Create multifd
migration threads"), multifd_load_cleanup() never returned any value
different than 0, neither set up any error on errp.

Even though, on process_incoming_migration_bh() an if clause uses it's
return value to decide on setting autostart = false, which will never
happen.

In order to simplify the codebase, change multifd_load_cleanup() signature
to 'void multifd_load_cleanup(void)', and for every usage remove error
handling or decision made based on return value != 0.

Fixes: b5eea99ec2 ("migration: Add yank feature")
Reported-by: Li Xiaohui <xiaohli@redhat.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-13 03:44:44 +01:00
Peter Xu
5655aab079 migration: Postpone postcopy preempt channel to be after main
Postcopy with preempt-mode enabled needs two channels to communicate.  The
order of channel establishment is not guaranteed.  It can happen that the
dest QEMU got the preempt channel connection request before the main
channel is established, then the migration may make no progress even during
precopy due to the wrong order.

To fix it, create the preempt channel only if we know the main channel is
established.

For a general postcopy migration, we delay it until postcopy_start(),
that's where we already went through some part of precopy on the main
channel.  To make sure dest QEMU has already established the channel, we
wait until we got the first PONG received.  That's something we do at the
start of precopy when postcopy enabled so it's guaranteed to happen sooner
or later.

For a postcopy recovery, we delay it to qemu_savevm_state_resume_prepare()
where we'll have round trips of data on bitmap synchronizations, which
means the main channel must have been established.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-11 16:51:09 +01:00
Peter Xu
b28fb58227 migration: Add a semaphore to count PONGs
This is mostly useless, but useful for us to know whether the main channel
is correctly established without changing the migration protocol.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-11 16:51:09 +01:00
Peter Xu
fc063a7b8a migration: Cleanup postcopy_preempt_setup()
Since we just dropped the only case where postcopy_preempt_setup() can
return an error, it doesn't need a retval anymore because it never fails.
Move the preempt check to the caller, preparing it to be used elsewhere to
do nothing but as simple as kicking the async connection.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-11 16:51:09 +01:00
Peter Xu
d6f74fd12e migration: Rework multi-channel checks on URI
The whole idea of multi-channel checks was not properly done, IMHO.

Currently we check multi-channel in a lot of places, but actually that's
not needed because we only need to check it right after we get the URI and
that should be it.

If the URI check succeeded, we should never need to check it again because
we must have it.  If it check fails, we should fail immediately on either
the qmp_migrate or qmp_migrate_incoming, instead of failingg it later after
the connection established.

Neither should we fail any set capabiliities like what we used to do here:

5ad15e8614 ("migration: allow enabling mutilfd for specific protocol only", 2021-10-19)

Because logically the URI will only be set later after the capability is
set, so it doesn't make a lot of sense to check the URI type when setting
the capability, because we're checking the cap with an old URI passed in,
and that may not even be the URI we're going to use later.

This patch mostly reverted all such checks for before, dropping the
variable migrate_allow_multi_channels and helpers.  Instead, add a common
helper to check URI for multi-channels for either qmp_migrate and
qmp_migrate_incoming and that should do all the proper checks.  The failure
will only trigger with the "migrate" or "migrate_incoming" command, or when
user specified "-incoming xxx" where "xxx" is not "defer".

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-11 16:51:09 +01:00
Jiang Jiacheng
1b1f4ab69c migration: save/delete migration thread info
To support query migration thread infomation, save and delete
thread(live_migration and multifdsend) information at thread
creation and finish.

Signed-off-by: Jiang Jiacheng <jiangjiacheng@huawei.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:57 +01:00
manish.mishra
6720c2b327 migration: check magic value for deciding the mapping of channels
Current logic assumes that channel connections on the destination side are
always established in the same order as the source and the first one will
always be the main channel followed by the multifid or post-copy
preemption channel. This may not be always true, as even if a channel has a
connection established on the source side it can be in the pending state on
the destination side and a newer connection can be established first.
Basically causing out of order mapping of channels on the destination side.
Currently, all channels except post-copy preempt send a magic number, this
patch uses that magic number to decide the type of channel. This logic is
applicable only for precopy(multifd) live migration, as mentioned, the
post-copy preempt channel does not send any magic number. Also, tls live
migrations already does tls handshake before creating other channels, so
this issue is not possible with tls, hence this logic is avoided for tls
live migrations. This patch uses read peek to check the magic number of
channels so that current data/control stream management remains
un-effected.

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Suggested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: manish.mishra <manish.mishra@nutanix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:57 +01:00
Peter Xu
db18dee7d7 migration: Show downtime during postcopy phase
The downtime should be displayed during postcopy phase because the
switchover phase is done.  OTOH it's weird to show "expected downtime"
which can confuse what does that mean if the switchover has already
happened anyway.

This is a slight ABI change on QMP, but I assume it shouldn't affect
anyone.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:56 +01:00
David Hildenbrand
80fe315c38 migration/ram: Factor out check for advised postcopy
Let's factor out this check, to be used in virtio-mem context next.

While at it, fix a spelling error in a related comment.

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>S
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:56 +01:00
David Hildenbrand
e3bf5e68e2 migration/savevm: Prepare vmdesc json writer in qemu_savevm_state_setup()
... and store it in the migration state. This is a preparation for
storing selected vmds's already in qemu_savevm_state_setup().

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06 19:22:56 +01:00
Juan Quintela
d9df92925e migration: simplify migration_iteration_run()
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2023-02-06 19:22:56 +01:00
Juan Quintela
fd70385d38 migration: Remove unused threshold_size parameter
Until previous commit, save_live_pending() was used for ram.  Now with
the split into state_pending_estimate() and state_pending_exact() it
is not needed anymore, so remove them.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2023-02-06 19:22:56 +01:00
Juan Quintela
c8df4a7aef migration: Split save_live_pending() into state_pending_*
We split the function into to:

- state_pending_estimate: We estimate the remaining state size without
  stopping the machine.

- state pending_exact: We calculate the exact amount of remaining
  state.

The only "device" that implements different functions for _estimate()
and _exact() is ram.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2023-02-06 19:22:56 +01:00
Juan Quintela
255dc7af7e migration: No save_live_pending() method uses the QEMUFile parameter
So remove it everywhere.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2023-02-06 19:22:56 +01:00
Markus Armbruster
27be86351e migration: Move the QMP command from monitor/ to migration/
This moves the command from MAINTAINERS sections "Human Monitor (HMP)"
and "QMP" to "Migration".

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230124121946.1139465-19-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2023-02-04 07:56:54 +01:00
Peter Maydell
928eac9539 Migration patches for 8.0
Hi
 
 This are the patches that I had to drop form the last PULL request because they werent fixes:
 - AVX2 is dropped, intel posted a fix, I have to redo it
 - Fix for out of order channels is out
   Daniel nacked it and I need to redo it
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Merge tag 'next-8.0-pull-request' of https://gitlab.com/juan.quintela/qemu into staging

Migration patches for 8.0

Hi

This are the patches that I had to drop form the last PULL request because they werent fixes:
- AVX2 is dropped, intel posted a fix, I have to redo it
- Fix for out of order channels is out
  Daniel nacked it and I need to redo it

# gpg: Signature made Thu 15 Dec 2022 09:38:29 GMT
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* tag 'next-8.0-pull-request' of https://gitlab.com/juan.quintela/qemu:
  migration: Drop rs->f
  migration: Remove old preempt code around state maintainance
  migration: Send requested page directly in rp-return thread
  migration: Move last_sent_block into PageSearchStatus
  migration: Make PageSearchStatus part of RAMState
  migration: Add pss_init()
  migration: Introduce pss_channel
  migration: Teach PSS about host page
  migration: Use atomic ops properly for page accountings
  migration: Yield bitmap_mutex properly when sending/sleeping
  migration: Remove RAMState.f references in compression code
  migration: Trivial cleanup save_page_header() on same block check
  migration: Cleanup xbzrle zero page cache update logic
  migration: Add postcopy_preempt_active()
  migration: Take bitmap mutex when completing ram migration
  migration: Export ram_release_page()
  migration: Export ram_transferred_ram()
  multifd: Create page_count fields into both MultiFD{Recv,Send}Params
  multifd: Create page_size fields into both MultiFD{Recv,Send}Params

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-12-15 14:52:13 +00:00
Peter Xu
b062106d3a migration: Remove old preempt code around state maintainance
With the new code to send pages in rp-return thread, there's little help to
keep lots of the old code on maintaining the preempt state in migration
thread, because the new way should always be faster..

Then if we'll always send pages in the rp-return thread anyway, we don't
need those logic to maintain preempt state anymore because now we serialize
things using the mutex directly instead of using those fields.

It's very unfortunate to have those code for a short period, but that's
still one intermediate step that we noticed the next bottleneck on the
migration thread.  Now what we can do best is to drop unnecessary code as
long as the new code is stable to reduce the burden.  It's actually a good
thing because the new "sending page in rp-return thread" model is (IMHO)
even cleaner and with better performance.

Remove the old code that was responsible for maintaining preempt states, at
the meantime also remove x-postcopy-preempt-break-huge parameter because
with concurrent sender threads we don't really need to break-huge anymore.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-12-15 10:30:37 +01:00
Peter Xu
9358982744 migration: Send requested page directly in rp-return thread
With all the facilities ready, send the requested page directly in the
rp-return thread rather than queuing it in the request queue, if and only
if postcopy preempt is enabled.  It can achieve so because it uses separate
channel for sending urgent pages.  The only shared data is bitmap and it's
protected by the bitmap_mutex.

Note that since we're moving the ownership of the urgent channel from the
migration thread to rp thread it also means the rp thread is responsible
for managing the qemufile, e.g. properly close it when pausing migration
happens.  For this, let migration_release_from_dst_file to cover shutdown
of the urgent channel too, renaming it as migration_release_dst_files() to
better show what it does.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-12-15 10:30:37 +01:00
Peter Xu
23b7576d78 migration: Use atomic ops properly for page accountings
To prepare for thread-safety on page accountings, at least below counters
need to be accessed only atomically, they are:

        ram_counters.transferred
        ram_counters.duplicate
        ram_counters.normal
        ram_counters.postcopy_bytes

There are a lot of other counters but they won't be accessed outside
migration thread, then they're still safe to be accessed without atomic
ops.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-12-15 10:30:37 +01:00
Markus Armbruster
720a252c26 qapi migration: Elide redundant has_FOO in generated C
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with.  Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step.  This is the step for qapi/migration.json.

Said commit explains the transformation in more detail.  The invariant
violations mentioned there do not occur here.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221104160712.3005652-17-armbru@redhat.com>
2022-12-14 20:04:47 +01:00
Peter Xu
6f39c90b86 migration: Disable multifd explicitly with compression
Multifd thread model does not work for compression, explicitly disable it.

Note that previuosly even we can enable both of them, nothing will go
wrong, because the compression code has higher priority so multifd feature
will just be ignored.  Now we'll fail even earlier at config time so the
user should be aware of the consequence better.

Note that there can be a slight chance of breaking existing users, but
let's assume they're not majority and not serious users, or they should
have found that multifd is not working already.

With that, we can safely drop the check in ram_save_target_page() for using
multifd, because when multifd=on then compression=off, then the removed
check on save_page_use_compression() will also always return false too.

Signed-off-by: Peter Xu <peterx@redhat.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>
2022-11-21 11:58:10 +01:00
Peter Xu
afed4273b5 migration: Disallow postcopy preempt to be used with compress
The preempt mode requires the capability to assign channel for each of the
page, while the compression logic will currently assign pages to different
compress thread/local-channel so potentially they're incompatible.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-11-21 11:58:10 +01:00
Marc-André Lureau
38e8f9af08 migration: add missing coroutine_fn annotations
Callers of coroutine_fn must be coroutine_fn themselves, or the call
must be within "if (qemu_in_coroutine())".  Apply coroutine_fn to
functions where this holds.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Faria <afaria@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220922084924.201610-26-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-07 12:11:41 +02:00
Peter Maydell
ead34f64f9 migration: Assert that migrate_multifd_compression() returns an in-range value
Coverity complains that when we use the return value from
migrate_multifd_compression() as an array index:
  multifd_recv_state->ops = multifd_ops[migrate_multifd_compression()];

that this might overrun the array (which is declared to have size
MULTIFD_COMPRESSION__MAX).  This is because the function return type
is MultiFDCompression, which is an autogenerated enum.  The code
generator includes the "one greater than the maximum possible value"
MULTIFD_COMPRESSION__MAX in the enum, even though this is not
actually a valid value for the enum, and this makes Coverity think
that migrate_multifd_compression() could return that __MAX value and
index off the end of the array.

Suppress the Coverity error by asserting that the value we're going
to return is within range.

Resolves: Coverity CID 1487239, 1487254
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220721115207.729615-2-peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-08-02 16:46:52 +01:00
Leonardo Bras
df67aa3e61 migration: add remaining params->has_* = true in migration_instance_init()
Some of params->has_* = true are missing in migration_instance_init, this
causes migrate_params_check() to skip some tests, allowing some
unsupported scenarios.

Fix this by adding all missing params->has_* = true in
migration_instance_init().

Fixes: 69ef1f36b0 ("migration: define 'tls-creds' and 'tls-hostname' migration parameters")
Fixes: 1d58872a91 ("migration: do not wait for free thread")
Fixes: d2f1d29b95 ("migration: add support for a "tls-authz" migration parameter")
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Message-Id: <20220726010235.342927-1-leobras@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-08-02 16:46:52 +01:00
Leonardo Bras
90eb69e4f1 migration: Avoid false-positive on non-supported scenarios for zero-copy-send
Migration with zero-copy-send currently has it's limitations, as it can't
be used with TLS nor any kind of compression. In such scenarios, it should
output errors during parameter / capability setting.

But currently there are some ways of setting this not-supported scenarios
without printing the error message:

!) For 'compression' capability, it works by enabling it together with
zero-copy-send. This happens because the validity test for zero-copy uses
the helper unction migrate_use_compression(), which check for compression
presence in s->enabled_capabilities[MIGRATION_CAPABILITY_COMPRESS].

The point here is: the validity test happens before the capability gets
enabled. If all of them get enabled together, this test will not return
error.

In order to fix that, replace migrate_use_compression() by directly testing
the cap_list parameter migrate_caps_check().

2) For features enabled by parameters such as TLS & 'multifd_compression',
there was also a possibility of setting non-supported scenarios: setting
zero-copy-send first, then setting the unsupported parameter.

In order to fix that, also add a check for parameters conflicting with
zero-copy-send on migrate_params_check().

3) XBZRLE is also a compression capability, so it makes sense to also add
it to the list of capabilities which are not supported with zero-copy-send.

Fixes: 1abaec9a1b ("migration: Change zero_copy_send from migration parameter to migration capability")
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Message-Id: <20220719122345.253713-1-leobras@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:09 +01:00
Leonardo Bras
cf20c89733 Add dirty-sync-missed-zero-copy migration stat
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220711211112.18951-3-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:09 +01:00
Peter Xu
9a26662752 migration: Export tls-[creds|hostname|authz] params to cmdline too
It's useful for specifying tls credentials all in the cmdline (along with
the -object tls-creds-*), especially for debugging purpose.

The trick here is we must remember to not free these fields again in the
finalize() function of migration object, otherwise it'll cause double-free.

The thing is when destroying an object, we'll first destroy the properties
that bound to the object, then the object itself.  To be explicit, when
destroy the object in object_finalize() we have such sequence of
operations:

    object_property_del_all(obj);
    object_deinit(obj, ti);

So after this change the two fields are properly released already even
before reaching the finalize() function but in object_property_del_all(),
hence we don't need to free them anymore in finalize() or it's double-free.

This also fixes a trivial memory leak for tls-authz as we forgot to free it
before this patch.

Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185515.27475-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:09 +01:00
Peter Xu
85a8578ea5 migration: Add helpers to detect TLS capability
Add migrate_channel_requires_tls() to detect whether the specific channel
requires TLS, leveraging the recently introduced migrate_use_tls().  No
functional change intended.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185513.27421-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Peter Xu
c8750de118 migration: Add property x-postcopy-preempt-break-huge
Add a property field that can conditionally disable the "break sending huge
page" behavior in postcopy preemption.  By default it's enabled.

It should only be used for debugging purposes, and we should never remove
the "x-" prefix.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Manish Mishra <manish.mishra@nutanix.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185511.27366-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Peter Xu
d0edb8a173 migration: Create the postcopy preempt channel asynchronously
This patch allows the postcopy preempt channel to be created
asynchronously.  The benefit is that when the connection is slow, we won't
take the BQL (and potentially block all things like QMP) for a long time
without releasing.

A function postcopy_preempt_wait_channel() is introduced, allowing the
migration thread to be able to wait on the channel creation.  The channel
is always created by the main thread, in which we'll kick a new semaphore
to tell the migration thread that the channel has created.

We'll need to wait for the new channel in two places: (1) when there's a
new postcopy migration that is starting, or (2) when there's a postcopy
migration to resume.

For the start of migration, we don't need to wait for this channel until
when we want to start postcopy, aka, postcopy_start().  We'll fail the
migration if we found that the channel creation failed (which should
probably not happen at all in 99% of the cases, because the main channel is
using the same network topology).

For a postcopy recovery, we'll need to wait in postcopy_pause().  In that
case if the channel creation failed, we can't fail the migration or we'll
crash the VM, instead we keep in PAUSED state, waiting for yet another
recovery.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Manish Mishra <manish.mishra@nutanix.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185509.27311-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Peter Xu
60bb3c5871 migration: Postcopy recover with preempt enabled
To allow postcopy recovery, the ram fast load (preempt-only) dest QEMU thread
needs similar handling on fault tolerance.  When ram_load_postcopy() fails,
instead of stopping the thread it halts with a semaphore, preparing to be
kicked again when recovery is detected.

A mutex is introduced to make sure there's no concurrent operation upon the
socket.  To make it simple, the fast ram load thread will take the mutex during
its whole procedure, and only release it if it's paused.  The fast-path socket
will be properly released by the main loading thread safely when there's
network failures during postcopy with that mutex held.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185506.27257-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Peter Xu
c01b16edf6 migration: Postcopy preemption enablement
This patch enables postcopy-preempt feature.

It contains two major changes to the migration logic:

(1) Postcopy requests are now sent via a different socket from precopy
    background migration stream, so as to be isolated from very high page
    request delays.

(2) For huge page enabled hosts: when there's postcopy requests, they can now
    intercept a partial sending of huge host pages on src QEMU.

After this patch, we'll live migrate a VM with two channels for postcopy: (1)
PRECOPY channel, which is the default channel that transfers background pages;
and (2) POSTCOPY channel, which only transfers requested pages.

There's no strict rule of which channel to use, e.g., if a requested page is
already being transferred on precopy channel, then we will keep using the same
precopy channel to transfer the page even if it's explicitly requested.  In 99%
of the cases we'll prioritize the channels so we send requested page via the
postcopy channel as long as possible.

On the source QEMU, when we found a postcopy request, we'll interrupt the
PRECOPY channel sending process and quickly switch to the POSTCOPY channel.
After we serviced all the high priority postcopy pages, we'll switch back to
PRECOPY channel so that we'll continue to send the interrupted huge page again.
There's no new thread introduced on src QEMU.

On the destination QEMU, one new thread is introduced to receive page data from
the postcopy specific socket (done in the preparation patch).

This patch has a side effect: after sending postcopy pages, previously we'll
assume the guest will access follow up pages so we'll keep sending from there.
Now it's changed.  Instead of going on with a postcopy requested page, we'll go
back and continue sending the precopy huge page (which can be intercepted by a
postcopy request so the huge page can be sent partially before).

Whether that's a problem is debatable, because "assuming the guest will
continue to access the next page" may not really suite when huge pages are
used, especially if the huge page is large (e.g. 1GB pages).  So that locality
hint is much meaningless if huge pages are used.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185504.27203-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Peter Xu
36f62f11e4 migration: Postcopy preemption preparation on channel creation
Create a new socket for postcopy to be prepared to send postcopy requested
pages via this specific channel, so as to not get blocked by precopy pages.

A new thread is also created on dest qemu to receive data from this new channel
based on the ram_load_postcopy() routine.

The ram_load_postcopy(POSTCOPY) branch and the thread has not started to
function, and that'll be done in follow up patches.

Cleanup the new sockets on both src/dst QEMUs, meanwhile look after the new
thread too to make sure it'll be recycled properly.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185502.27149-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: With Peter's fix to quieten compiler warning on
       start_migration
2022-07-20 12:15:08 +01:00
Peter Xu
ce5b0f4afc migration: Add postcopy-preempt capability
Firstly, postcopy already preempts precopy due to the fact that we do
unqueue_page() first before looking into dirty bits.

However that's not enough, e.g., when there're host huge page enabled, when
sending a precopy huge page, a postcopy request needs to wait until the whole
huge page that is sending to finish.  That could introduce quite some delay,
the bigger the huge page is the larger delay it'll bring.

This patch adds a new capability to allow postcopy requests to preempt existing
precopy page during sending a huge page, so that postcopy requests can be
serviced even faster.

Meanwhile to send it even faster, bypass the precopy stream by providing a
standalone postcopy socket for sending requested pages.

Since the new behavior will not be compatible with the old behavior, this will
not be the default, it's enabled only when the new capability is set on both
src/dst QEMUs.

This patch only adds the capability itself, the logic will be added in follow
up patches.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185342.26794-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-07-20 12:15:08 +01:00
Daniel P. Berrangé
77ef2dc1c8 migration: remove the QEMUFileOps abstraction
Now that all QEMUFile callbacks are removed, the entire concept can be
deleted.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-06-23 10:18:13 +01:00
Daniel P. Berrangé
fbfa6404e5 migration: rename qemu_ftell to qemu_file_total_transferred
The name 'ftell' gives the misleading impression that the QEMUFile
objects are seekable. This is not the case, as in general we just
have an opaque stream. The users of this method are only interested
in the total bytes processed. This switches to a new name that
reflects the intended usage.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
   dgilbert: Wrapped long line
2022-06-22 19:33:36 +01:00
Leonardo Bras
1abaec9a1b migration: Change zero_copy_send from migration parameter to migration capability
When originally implemented, zero_copy_send was designed as a Migration
paramenter.

But taking into account how is that supposed to work, and how
the difference between a capability and a parameter, it only makes sense
that zero-copy-send would work better as a capability.

Taking into account how recently the change got merged, it was decided
that it's still time to make it right, and convert zero_copy_send into
a Migration capability.

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: always define the capability, even on non-Linux but error if
set; avoids build problems with the capability
2022-06-22 18:11:17 +01:00
Leonardo Bras
5b1d9bab2d multifd: Implement zero copy write in multifd migration (multifd-zero-copy)
Implement zero copy send on nocomp_send_write(), by making use of QIOChannel
writev + flags & flush interface.

Change multifd_send_sync_main() so flush_zero_copy() can be called
after each iteration in order to make sure all dirty pages are sent before
a new iteration is started. It will also flush at the beginning and at the
end of migration.

Also make it return -1 if flush_zero_copy() fails, in order to cancel
the migration process, and avoid resuming the guest in the target host
without receiving all current RAM.

This will work fine on RAM migration because the RAM pages are not usually freed,
and there is no problem on changing the pages content between writev_zero_copy() and
the actual sending of the buffer, because this change will dirty the page and
cause it to be re-sent on a next iteration anyway.

A lot of locked memory may be needed in order to use multifd migration
with zero-copy enabled, so disabling the feature should be necessary for
low-privileged users trying to perform multifd migrations.

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220513062836.965425-9-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-05-16 13:56:24 +01:00
Leonardo Bras
d2fafb6a68 migration: Add migrate_use_tls() helper
A lot of places check parameters.tls_creds in order to evaluate if TLS is
in use, and sometimes call migrate_get_current() just for that test.

Add new helper function migrate_use_tls() in order to simplify testing
for TLS usage.

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220513062836.965425-6-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-05-16 13:56:24 +01:00
Leonardo Bras
abb6295b3a migration: Add zero-copy-send parameter for QMP/HMP for Linux
Add property that allows zero-copy migration of memory pages
on the sending side, and also includes a helper function
migrate_use_zero_copy_send() to check if it's enabled.

No code is introduced to actually do the migration, but it allow
future implementations to enable/disable this feature.

On non-Linux builds this parameter is compiled-out.

Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220513062836.965425-5-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-05-16 13:56:24 +01:00
Dr. David Alan Gilbert
552de79bfd migration: Read state once
The 'status' field for the migration is updated normally using
an atomic operation from the migration thread.
Most readers of it aren't that careful, and in most cases it doesn't
matter.

In query_migrate->fill_source_migration_info the 'state'
is read twice; the first time to decide which state fields to fill in,
and then secondly to copy the state to the status field; that can end up
with a status that's inconsistent; e.g. setting up the fields
for 'setup' and then having an 'active' status.  In that case
libvirt gets upset by the lack of ram info.
The symptom is:
   libvirt.libvirtError: internal error: migration was active, but no RAM info was set

Read the state exactly once in fill_source_migration_info.

This is a possible fix for:
https://bugzilla.redhat.com/show_bug.cgi?id=2074205

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220413113329.103696-1-dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-04-21 19:36:46 +01:00
Peter Xu
08401c0426 migration: Allow migrate-recover to run multiple times
Previously migration didn't have an easy way to cleanup the listening
transport, migrate recovery only allows to execute once.  That's done with a
trick flag in postcopy_recover_triggered.

Now the facility is already there.

Drop postcopy_recover_triggered and instead allows a new migrate-recover to
release the previous listener transport.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220331150857.74406-8-peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-04-21 19:36:46 +01:00
Peter Xu
a39e933962 migration: Move channel setup out of postcopy_try_recover()
We used to use postcopy_try_recover() to replace migration_incoming_setup() to
setup incoming channels.  That's fine for the old world, but in the new world
there can be more than one channels that need setup.  Better move the channel
setup out of it so that postcopy_try_recover() only handles the last phase of
switching to the recovery phase.

To do that in migration_fd_process_incoming(), move the postcopy_try_recover()
call to be after migration_incoming_setup(), which will setup the channels.
While in migration_ioc_process_incoming(), postpone the recover() routine right
before we'll jump into migration_incoming_process().

A side benefit is we don't need to pass in QEMUFile* to postcopy_try_recover()
anymore.  Remove it.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220331150857.74406-7-peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-04-21 19:36:46 +01:00
Peter Xu
f444eeda71 migration: Move migrate_allow_multifd and helpers into migration.c
This variable, along with its helpers, is used to detect whether multiple
channel will be supported for migration.  In follow up patches, there'll be
other capability that requires multi-channels.  Hence move it outside multifd
specific code and make it public.  Meanwhile rename it from "multifd" to
"multi_channels" to show its real meaning.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220331150857.74406-5-peterx@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-04-21 19:36:46 +01:00
Peter Xu
83174765da migration: Postpone releasing MigrationState.hostname
We used to release it right after migrate_fd_connect().  That's not good
enough when there're more than one socket pair required, because it'll be
needed to establish TLS connection for the rest channels.

One example is multifd, where we copied over the hostname for each channel
but that's actually not needed.

Keeping the hostname until the cleanup phase of migration.

Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220331150857.74406-2-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: Fixup checkpatch error; don't need to check for NULL
  around g_free
2022-04-21 19:36:46 +01:00
Marc-André Lureau
8e3b0cbb72 Replace qemu_real_host_page variables with inlined functions
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.

This avoids the need for a constructor initialization too.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:38 +02:00
Emanuele Giuseppe Esposito
3b71719462 block: rename bdrv_invalidate_cache_all, blk_invalidate_cache and test_sync_op_invalidate_cache
Following the bdrv_activate renaming, change also the name
of the respective callers.

bdrv_invalidate_cache_all -> bdrv_activate_all
blk_invalidate_cache -> blk_activate
test_sync_op_invalidate_cache -> test_sync_op_activate

No functional change intended.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220209105452.1694545-5-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:14:40 +01:00
Peter Xu
e031149c78 migration: Add migration_incoming_transport_cleanup()
Add a helper to cleanup the transport listener.

When do it, we should also null-ify the cleanup hook and the data, then it's
even safe to call it multiple times.

Move the socket_address_list cleanup altogether, because that's a mirror of the
listener channels and only for the purpose of query-migrate.  Hence when
someone wants to cleanup the listener transport, it should also want to cleanup
the socket list too, always.

No functional change intended.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220301083925.33483-15-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02 18:20:45 +00:00
Peter Xu
d5c8f2afe8 migration: Enlarge postcopy recovery to capture !-EIO too
We used to have quite a few places making sure -EIO happened and that's the
only way to trigger postcopy recovery.  That's based on the assumption that
we'll only return -EIO for channel issues.

It'll work in 99.99% cases but logically that won't cover some corner cases.
One example is e.g. ram_block_from_stream() could fail with an interrupted
network, then -EINVAL will be returned instead of -EIO.

I remembered Dave Gilbert pointed that out before, but somehow this is
overlooked.  Neither did I encounter anything outside the -EIO error.

However we'd better touch that up before it triggers a rare VM data loss during
live migrating.

To cover as much those cases as possible, remove the -EIO restriction on
triggering the postcopy recovery, because even if it's not a channel failure,
we can't do anything better than halting QEMU anyway - the corpse of the
process may even be used by a good hand to dig out useful memory regions, or
the admin could simply kill the process later on.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220301083925.33483-11-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-03-02 18:20:45 +00:00
David Edmondson
ae68066880 migration: Tally pre-copy, downtime and post-copy bytes independently
Provide information on the number of bytes copied in the pre-copy,
downtime and post-copy phases of migration.

Signed-off-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-01-28 15:38:23 +01:00
Peter Xu
739fcc1b0e migration: Drop return code for disgard ram process
It will just never fail.  Drop those return values where they're constantly
zeros.

A tiny touch-up on the tracepoint so trace_ram_postcopy_send_discard_bitmap()
is called after the logic itself (which sounds more reasonable).

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.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>
2022-01-28 15:38:23 +01:00
Zhang Chen
01ee5e3556 migration/migration.c: Remove the MIGRATION_STATUS_ACTIVE when migration finished
The MIGRATION_STATUS_ACTIVE indicates that migration is running.
Remove it to be handled by the default operation,
It should be part of the unknown ending states.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-01-28 15:38:23 +01:00
Zhang Chen
eeeb48ee33 migration/migration.c: Avoid COLO boot in postcopy migration
COLO dose not support postcopy migration and remove the Fixme.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2022-01-28 15:38:23 +01:00
Zhang Chen
444252b96a migration/migration.c: Add missed default error handler for migration state
In the migration_completion() no other status is expected, for
example MIGRATION_STATUS_CANCELLING, MIGRATION_STATUS_CANCELLED, etc.

Signed-off-by: Zhang Chen <chen.zhang@intel.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>
2022-01-28 15:38:23 +01:00
Laurent Vivier
1b529d908d failover: Silence warning messages during qtest
virtio-net-failover test tries several device combinations that produces
some expected warnings.
These warning can be confusing, so we disable them during the qtest
sequence.

Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20211220145314.390697-1-lvivier@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
[thuth: Fix memory leak by using error_free()]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-12-22 08:12:45 +01:00
Juan Quintela
144fa06b34 migration: Never call twice qemu_target_page_size()
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-12-15 10:31:42 +01:00
Zhang Chen
751fe4c608 migration/colo: Optimize COLO primary node start code path
Optimize COLO primary start path from:
MIGRATION_STATUS_XXX --> MIGRATION_STATUS_ACTIVE --> MIGRATION_STATUS_COLO --> MIGRATION_STATUS_COMPLETED
To:
MIGRATION_STATUS_XXX --> MIGRATION_STATUS_COLO --> MIGRATION_STATUS_COMPLETED
No need to start primary COLO through "MIGRATION_STATUS_ACTIVE".

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-12-15 10:31:42 +01:00
Rao, Lei
795969ab1f Fixed a QEMU hang when guest poweroff in COLO mode
When the PVM guest poweroff, the COLO thread may wait a semaphore
in colo_process_checkpoint().So, we should wake up the COLO thread
before migration shutdown.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-12-15 10:31:42 +01:00
Rao, Lei
684bfd1820 Fixed SVM hang when do failover before PVM crash
This patch fixed as follows:
    Thread 1 (Thread 0x7f34ee738d80 (LWP 11212)):
    #0 __pthread_clockjoin_ex (threadid=139847152957184, thread_return=0x7f30b1febf30, clockid=<optimized out>, abstime=<optimized out>, block=<optimized out>) at pthread_join_common.c:145
    #1 0x0000563401998e36 in qemu_thread_join (thread=0x563402d66610) at util/qemu-thread-posix.c:587
    #2 0x00005634017a79fa in process_incoming_migration_co (opaque=0x0) at migration/migration.c:502
    #3 0x00005634019b59c9 in coroutine_trampoline (i0=63395504, i1=22068) at util/coroutine-ucontext.c:115
    #4 0x00007f34ef860660 in ?? () at ../sysdeps/unix/sysv/linux/x86_64/__start_context.S:91 from /lib/x86_64-linux-gnu/libc.so.6
    #5 0x00007f30b21ee730 in ?? ()
    #6 0x0000000000000000 in ?? ()

    Thread 13 (Thread 0x7f30b3dff700 (LWP 11747)):
    #0  __lll_lock_wait (futex=futex@entry=0x56340218ffa0 <qemu_global_mutex>, private=0) at lowlevellock.c:52
    #1  0x00007f34efa000a3 in _GI__pthread_mutex_lock (mutex=0x56340218ffa0 <qemu_global_mutex>) at ../nptl/pthread_mutex_lock.c:80
    #2  0x0000563401997f99 in qemu_mutex_lock_impl (mutex=0x56340218ffa0 <qemu_global_mutex>, file=0x563401b7a80e "migration/colo.c", line=806) at util/qemu-thread-posix.c:78
    #3  0x0000563401407144 in qemu_mutex_lock_iothread_impl (file=0x563401b7a80e "migration/colo.c", line=806) at /home/workspace/colo-qemu/cpus.c:1899
    #4  0x00005634017ba8e8 in colo_process_incoming_thread (opaque=0x563402d664c0) at migration/colo.c:806
    #5  0x0000563401998b72 in qemu_thread_start (args=0x5634039f8370) at util/qemu-thread-posix.c:519
    #6  0x00007f34ef9fd609 in start_thread (arg=<optimized out>) at pthread_create.c:477
    #7  0x00007f34ef924293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

    The QEMU main thread is holding the lock:
    (gdb) p qemu_global_mutex
    $1 = {lock = {_data = {lock = 2, __count = 0, __owner = 11212, __nusers = 9, __kind = 0, __spins = 0, __elision = 0, __list = {_prev = 0x0, __next = 0x0}},
     __size = "\002\000\000\000\000\000\000\000\314+\000\000\t", '\000' <repeats 26 times>, __align = 2}, file = 0x563401c07e4b "util/main-loop.c", line = 240,
    initialized = true}

>From the call trace, we can see it is a deadlock bug. and the QEMU main thread holds the global mutex to wait until the COLO thread ends. and the colo thread
wants to acquire the global mutex, which will cause a deadlock. So, we should release the qemu_global_mutex before waiting colo thread ends.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Reviewed-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-03 09:38:53 +01:00
Rao, Lei
aa505f8e0e Fixed qemu crash when guest power off in COLO mode
This patch fixes the following:
qemu-system-x86_64: invalid runstate transition: 'shutdown' -> 'running'
Aborted (core dumped)
The gdb bt as following:
0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
1  0x00007faa3d613859 in __GI_abort () at abort.c:79
2  0x000055c5a21268fd in runstate_set (new_state=RUN_STATE_RUNNING) at vl.c:723
3  0x000055c5a1f8cae4 in vm_prepare_start () at /home/workspace/colo-qemu/cpus.c:2206
4  0x000055c5a1f8cb1b in vm_start () at /home/workspace/colo-qemu/cpus.c:2213
5  0x000055c5a2332bba in migration_iteration_finish (s=0x55c5a4658810) at migration/migration.c:3376
6  0x000055c5a2332f3b in migration_thread (opaque=0x55c5a4658810) at migration/migration.c:3527
7  0x000055c5a251d68a in qemu_thread_start (args=0x55c5a5491a70) at util/qemu-thread-posix.c:519
8  0x00007faa3d7e9609 in start_thread (arg=<optimized out>) at pthread_create.c:477
9  0x00007faa3d710293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Signed-off-by: Lei Rao <lei.rao@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-03 09:38:53 +01:00
yuxiating
fa0b31d585 migration: initialise compression_counters for a new migration
If the compression migration fails or is canceled, the query for the value of
compression_counters during the next compression migration is wrong.

Signed-off-by: yuxiating <yuxiating@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-03 09:38:53 +01:00
Laurent Vivier
458fecca80 migration: provide an error message to migration_cancel()
This avoids to call migrate_get_current() in the caller function
whereas migration_cancel() already needs the pointer to the current
migration state.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-03 09:38:53 +01:00
David Hildenbrand
7648297d40 migration: Simplify alignment and alignment checks
Let's use QEMU_ALIGN_DOWN() and friends to make the code a bit easier to
read.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-01 22:56:44 +01:00
Peter Xu
60fd680193 migration: Add migrate_add_blocker_internal()
An internal version that removes -only-migratable implications.  It can be used
for temporary migration blockers like dump-guest-memory.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-01 22:56:44 +01:00
Peter Xu
4c170330aa migration: Make migration blocker work for snapshots too
save_snapshot() checks migration blocker, which looks sane.  At the meantime we
should also teach the blocker add helper to fail if during a snapshot, just
like for migrations.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-11-01 22:56:43 +01:00
Li Zhijian
5ad15e8614 migration: allow enabling mutilfd for specific protocol only
To: <quintela@redhat.com>, <dgilbert@redhat.com>, <qemu-devel@nongnu.org>
CC: Li Zhijian <lizhijian@cn.fujitsu.com>
Date: Sat, 31 Jul 2021 22:05:52 +0800 (5 weeks, 4 days, 17 hours ago)

And change the default to true so that in '-incoming defer' case, user is able
to change multifd capability.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-10-19 08:39:04 +02:00
Li Zhijian
b7acd65707 migration: allow multifd for socket protocol only
To: <quintela@redhat.com>, <dgilbert@redhat.com>, <qemu-devel@nongnu.org>
CC: Li Zhijian <lizhijian@cn.fujitsu.com>
Date: Sat, 31 Jul 2021 22:05:51 +0800 (5 weeks, 4 days, 17 hours ago)

multifd with unsupported protocol will cause a segment fault.
(gdb) bt
 #0  0x0000563b4a93faf8 in socket_connect (addr=0x0, errp=0x7f7f02675410) at ../util/qemu-sockets.c:1190
 #1 0x0000563b4a797a03 in qio_channel_socket_connect_sync
(ioc=0x563b4d16e8c0, addr=0x0, errp=0x7f7f02675410) at
../io/channel-socket.c:145
 #2  0x0000563b4a797abf in qio_channel_socket_connect_worker (task=0x563b4cd86c30, opaque=0x0) at ../io/channel-socket.c:168
 #3  0x0000563b4a792631 in qio_task_thread_worker (opaque=0x563b4cd86c30) at ../io/task.c:124
 #4  0x0000563b4a91da69 in qemu_thread_start (args=0x563b4c44bb80) at ../util/qemu-thread-posix.c:541
 #5  0x00007f7fe9b5b3f9 in ?? ()
 #6  0x0000000000000000 in ?? ()

It's enough to check migrate_multifd_is_allowed() in multifd cleanup() and
multifd setup() though there are so many other places using migrate_use_multifd().

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2021-10-19 08:39:04 +02:00
Emanuele Giuseppe Esposito
68b88468f6 migration: add missing qemu_mutex_lock_iothread in migration_completion
qemu_savevm_state_complete_postcopy assumes the iothread lock (BQL)
to be held, but instead it isn't.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20211005080751.3797161-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-10-05 13:10:29 +02:00
Markus Armbruster
7d6f6933aa migration: Handle migration_incoming_setup() errors consistently
Commit b673eab4e2 "multifd: Make multifd_load_setup() get an Error
parameter" changed migration_incoming_setup() to take an Error **
argument, and adjusted the callers accordingly.  It neglected to
change adjust multifd_load_setup(): it still exit()s on error.  Clean
that up.

The error now gets propagated up two call chains: via
migration_fd_process_incoming() to rdma_accept_incoming_migration(),
and via migration_ioc_process_incoming() to
migration_channel_process_incoming().  Both chain ends report the
error with error_report_err(), but otherwise ignore it.  Behavioral
change: we no longer exit() on this error.

This is consistent with how we handle other errors here, e.g. from
multifd_recv_new_channel() via migration_ioc_process_incoming() to
migration_channel_process_incoming().  Whether it's consistently right
or consistently wrong I can't tell.

Also clean up the return value from the unusual 0 on success, 1 on
error to the more common true on success, false on error.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-11-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@ionos.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2021-08-26 17:15:28 +02:00
Markus Armbruster
f9734d5d40 error: Use error_fatal to simplify obvious fatal errors (again)
We did this with scripts/coccinelle/use-error_fatal.cocci before, in
commit 50beeb6809 and 007b06578a.  This commit cleans up rarer
variations that don't seem worth matching with Coccinelle.

Cc: Thomas Huth <thuth@redhat.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-08-26 17:15:28 +02:00
Peter Xu
39675ffffb migration: Move the yank unregister of channel_close out
It's efficient, but hackish to call yank unregister calls in channel_close(),
especially it'll be hard to debug when qemu crashed with some yank function
leaked.

Remove that hack, but instead explicitly unregister yank functions at the
places where needed, they are:

  (on src)
  - migrate_fd_cleanup
  - postcopy_pause

  (on dst)
  - migration_incoming_state_destroy
  - postcopy_pause_incoming

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210722175841.938739-6-peterx@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-26 12:45:03 +01:00
Peter Xu
43044ac0ee migration: Make from_dst_file accesses thread-safe
Accessing from_dst_file is potentially racy in current code base like below:

  if (s->from_dst_file)
    do_something(s->from_dst_file);

Because from_dst_file can be reset right after the check in another
thread (rp_thread).  One example is migrate_fd_cancel().

Use the same qemu_file_lock to protect it too, just like to_dst_file.

When it's safe to access without lock, comment it.

There's one special reference in migration_thread() that can be replaced by
the newly introduced rp_thread_created flag.

Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Message-Id: <20210722175841.938739-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  with Peter's fixup
2021-07-26 12:44:46 +01:00
Peter Xu
53021ea165 migration: Fix missing join() of rp_thread
It's possible that the migration thread skip the join() of the rp_thread in
below race and crash on src right at finishing migration:

       migration_thread                     rp_thread
       ----------------                     ---------
    migration_completion()
                                        (before rp_thread quits)
                                        from_dst_file=NULL
                                        [thread got scheduled out]
      s->rp_state.from_dst_file==NULL
        (skip join() of rp_thread)
    migrate_fd_cleanup()
      qemu_fclose(s->to_dst_file)
      yank_unregister_instance()
        assert(yank_find_entry())  <------- crash

It could mostly happen with postcopy, but that shouldn't be required, e.g., I
think it could also trigger with MIGRATION_CAPABILITY_RETURN_PATH set.

It's suspected that above race could be the root cause of a recent (but rare)
migration-test break reported by either Dave or PMM:

https://lore.kernel.org/qemu-devel/YPamXAHwan%2FPPXLf@work-vm/

The issue is: from_dst_file is reset in the rp_thread, so if the thread reset
it to NULL fast enough then the migration thread will assume there's no
rp_thread at all.

This could potentially cause more severe issue (e.g. crash) after the yank code.

Fix it by using a boolean to keep "whether we've created rp_thread".

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210722175841.938739-2-peterx@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-26 12:44:26 +01:00
Peter Xu
ca7bd0821b migration: Clear error at entry of migrate_fd_connect()
For each "migrate" command, remember to clear the s->error before going on.
For one reason, when there's a new error it'll be still remembered; see
migrate_set_error() who only sets the error if error==NULL.  Meanwhile if a
failed migration completes (e.g., postcopy recovered and finished), we
shouldn't dump an error when calling migrate_fd_cleanup() at last.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-4-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-13 16:21:57 +01:00
Peter Xu
ca30f24d12 migration: Don't do migrate cleanup if during postcopy resume
Below process could crash qemu with postcopy recovery:

  1. (hmp) migrate -d ..
  2. (hmp) migrate_start_postcopy
  3. [network down, postcopy paused]
  4. (hmp) migrate -r $WRONG_PORT
     when try the recover on an invalid $WRONG_PORT, cleanup_bh will be cleared
  5. (hmp) migrate -r $RIGHT_PORT
     [qemu crash on assert(cleanup_bh)]

The thing is we shouldn't cleanup if it's postcopy resume; the error is set
mostly because the channel is wrong, so we return directly waiting for the user
to retry.

migrate_fd_cleanup() should only be called when migration is cancelled or
completed.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-3-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-13 16:21:57 +01:00
Peter Xu
2e3e3da3c2 migration: Release return path early for paused postcopy
When postcopy pause triggered, we rely on the migration thread to cleanup the
to_dst_file handle, and the return path thread to cleanup the from_dst_file
handle (which is stored in the local variable "rp").

Within the process, from_dst_file cleanup (qemu_fclose) is postponed until it's
setup again due to a postcopy recovery.

It used to work before yank was born; after yank is introduced we rely on the
refcount of IOC to correctly unregister yank function in channel_close().  If
without the early and on-time release of from_dst_file handle the yank function
will be leftover during paused postcopy.

Without this patch, below steps (quoted from Xiaohui) could trigger qemu src
crash:

  1.Boot vm on src host
  2.Boot vm on dst host
  3.Enable postcopy on src&dst host
  4.Load stressapptest in vm and set postcopy speed to 50M
  5.Start migration from src to dst host, change into postcopy mode when migration is active.
  6.When postcopy is active, down the network card(do migration via this network) on dst host.
  7.Wait untill postcopy is paused on src&dst host.
  8.Before up network card, recover migration on dst host, will get error like following.
  9.Ignore the error of step 8, go on recovering migration on src host:

  After step 9, qemu on src host will core dump after some seconds:
  qemu-kvm: ../util/yank.c:107: yank_unregister_instance: Assertion `QLIST_EMPTY(&entry->yankfns)' failed.
  1.sh: line 38: 44662 Aborted                 (core dumped)

Reported-by: Li Xiaohui <xiaohli@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210708190653.252961-2-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-13 16:21:57 +01:00
Laurent Vivier
a51dcef08b migration: failover: emit a warning when the card is not fully unplugged
When the migration fails or is canceled we wait the end of the unplug
operation to be able to plug it back. But if the unplug operation
is never finished we stop to wait and QEMU emits a warning to inform
the user.

Based-on: 20210629155007.629086-1-lvivier@redhat.com
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20210701131458.112036-1-lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-13 16:21:57 +01:00
Laurent Vivier
944bc52842 migration: failover: continue to wait card unplug on error
If the user cancels the migration in the unplug-wait state,
QEMU will try to plug back the card and this fails because the card
is partially unplugged.
To avoid the problem, continue to wait the card unplug, but to
allow the migration to be canceled if the card never finishes to unplug
use a timeout.

Bug: https://bugzilla.redhat.com/show_bug.cgi?id=1976852
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210629155007.629086-3-lvivier@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-05 10:51:26 +01:00
Laurent Vivier
fde93d99d9 migration: move wait-unplug loop to its own function
The loop is used in migration_thread() and bg_migration_thread(),
so we can move it to its own function and call it from these both places.

Moreover, in migration_thread() we have a wrong state transition from
SETUP to ACTIVE while state could be WAIT_UNPLUG. This is correctly
managed in bg_migration_thread() so use this code instead.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20210629155007.629086-2-lvivier@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-05 10:51:26 +01:00
Peter Xu
b7f9afd48e migration: Allow reset of postcopy_recover_triggered when failed
It's possible qemu_start_incoming_migration() failed at any point, when it
happens we should reset postcopy_recover_triggered to false so that the user
can still retry with a saner incoming port.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210629181356.217312-3-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-05 10:51:26 +01:00
Peter Xu
cc48c587d2 migration: Move yank outside qemu_start_incoming_migration()
Starting from commit b5eea99ec2, qmp_migrate_recover() calls unregister
before calling qemu_start_incoming_migration(). I believe it wanted to mitigate
the next call to yank_register_instance(), but I think that's wrong.

Firstly, if during recover, we should keep the yank instance there, not
"quickly removing and adding it back".

Meanwhile, calling qmp_migrate_recover() twice with b5eea99ec2 will directly
crash the dest qemu (right now it can't; but it'll start to work right after
the next patch) because the 1st call of qmp_migrate_recover() will unregister
permanently when the channel failed to establish, then the 2nd call of
qmp_migrate_recover() crashes at yank_unregister_instance().

This patch fixes it by moving yank ops out of qemu_start_incoming_migration()
into qmp_migrate_incoming.  For qmp_migrate_recover(), drop the unregister of
yank instance too since we keep it there during the recovery phase.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210629181356.217312-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-07-05 10:51:26 +01:00
Daniel P. Berrangé
626ff6515d migration: add trace point when vm_stop_force_state fails
This is a critical failure scenario for migration that is hard to
diagnose from existing probes. Most likely it is caused by an error
from bdrv_flush(), but we're not logging the errno anywhere, hence
this new probe.

Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-06-14 13:28:50 +01:00
Rao, Lei
3ba024457f Remove migrate_set_block_enabled in checkpoint
We can detect disk migration in migrate_prepare, if disk migration
is enabled in COLO mode, we can directly report an error.and there
is no need to disable block migration at every checkpoint.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Tested-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-06-11 10:30:13 +08:00
Dr. David Alan Gilbert
1df6ddb43b migration: Add cleanup hook for inwards migration
Add a cleanup hook for incoming migration that gets called
at the end as a way for a transport to allow cleanup.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210421112834.107651-4-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-06-08 19:36:18 +01:00
Peter Maydell
9b1e81d1c2 * Replace YAML anchors by extends in the gitlab-CI yaml files
* Many small qtest fixes (e.g. to fix issues discovered by Coverity)
 * Poison more config switches in common code
 * Fix the failing Travis-CI and Cirrus-CI tasks
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Merge remote-tracking branch 'remotes/thuth-gitlab/tags/pull-request-2021-05-14' into staging

* Replace YAML anchors by extends in the gitlab-CI yaml files
* Many small qtest fixes (e.g. to fix issues discovered by Coverity)
* Poison more config switches in common code
* Fix the failing Travis-CI and Cirrus-CI tasks

# gpg: Signature made Fri 14 May 2021 12:17:39 BST
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/thuth-gitlab/tags/pull-request-2021-05-14:
  cirrus.yml: Fix the MSYS2 task
  pc-bios/s390-ccw: Fix inline assembly for older versions of Clang
  tests/qtest/migration-test: Use g_autofree to avoid leaks on error paths
  configure: Poison all current target-specific #defines
  migration: Move populate_vfio_info() into a separate file
  include/sysemu: Poison all accelerator CONFIG switches in common code
  tests: Avoid side effects inside g_assert() arguments
  tests/qtest/rtc-test: Remove pointless NULL check
  tests/qtest/tpm-util.c: Free memory with correct free function
  tests/migration-test: Fix "true" vs true
  tests/qtest/npcm7xx_pwm-test.c: Avoid g_assert_true() for non-test assertions
  tests/qtest/ahci-test.c: Calculate iso_size with 64-bit arithmetic
  util/compatfd.c: Replaced a malloc call with g_malloc.
  libqtest: refuse QTEST_QEMU_BINARY=qemu-kvm
  docs/devel/qgraph: add troubleshooting information
  libqos/qgraph: fix "UNAVAILBLE" typo
  gitlab-ci: Replace YAML anchors by extends (native_test_job)
  gitlab-ci: Replace YAML anchors by extends (native_build_job)
  gitlab-ci: Replace YAML anchors by extends (container_job)
  tests/docker/dockerfiles: Add ccache to containers where it was missing

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-05-14 19:33:23 +01:00
Thomas Huth
43bd0bf30f migration: Move populate_vfio_info() into a separate file
The CONFIG_VFIO switch only works in target specific code. Since
migration/migration.c is common code, the #ifdef does not have
the intended behavior here. Move the related code to a separate
file now which gets compiled via specific_ss instead.

Fixes: 3710586caa ("qapi: Add VFIO devices migration stats in Migration stats")
Message-Id: <20210414112004.943383-3-thuth@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-05-14 12:31:51 +02:00
David Hildenbrand
c7c0e72408 migration/ram: Handle RAM block resizes during precopy
Resizing while migrating is dangerous and does not work as expected.
The whole migration code works on the usable_length of ram blocks and does
not expect this to change at random points in time.

In the case of precopy, the ram block size must not change on the source,
after syncing the RAM block list in ram_save_setup(), so as long as the
guest is still running on the source.

Resizing can be trigger *after* (but not during) a reset in
ACPI code by the guest
- hw/arm/virt-acpi-build.c:acpi_ram_update()
- hw/i386/acpi-build.c:acpi_ram_update()

Use the ram block notifier to get notified about resizes. Let's simply
cancel migration and indicate the reason. We'll continue running on the
source. No harm done.

Update the documentation. Postcopy will be handled separately.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210429112708.12291-5-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Manual merge
2021-05-13 18:21:13 +01:00
Markus Armbruster
372043f389 migration: Drop redundant query-migrate result @blocked
Result @blocked is redundant.  Unfortunately, we realized this too
close to the release to risk dropping it, so we deprecated it
instead, in commit e11ce6c06.

Since it was deprecated from the start, we can delete it without
the customary grace period.  Do so.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210429140424.2802929-1-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-05-13 18:21:13 +01:00
Andrey Gruzdev
eeccb99c9d migration: Pre-fault memory before starting background snasphot
This commit solves the issue with userfault_fd WP feature that
background snapshot is based on. For any never poluated or discarded
memory page, the UFFDIO_WRITEPROTECT ioctl() would skip updating
PTE for that page, thereby loosing WP setting for it.

So we need to pre-fault pages for each RAM block to be protected
before making a userfault_fd wr-protect ioctl().

Fixes: 278e2f551a (migration: support
  UFFD write fault processing in ram_save_iterate())
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-4-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert:
  Bodged ifdef __linux__ on ram_write_tracking_prepare, should really
      go in a stub
2021-04-07 18:37:28 +01:00
Andrey Gruzdev
1a8e44a89f migration: Inhibit virtio-balloon for the duration of background snapshot
The same thing as for incoming postcopy - we cannot deal with concurrent
RAM discards when using background snapshot feature in outgoing migration.

Fixes: 8518278a6a (migration: implementation
  of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-3-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-06 18:56:01 +01:00
Andrey Gruzdev
ecb23efea0 migration: Fix missing qemu_fflush() on buffer file in bg_migration_thread
Added missing qemu_fflush() on buffer file holding precopy device state.
Increased initial QIOChannelBuffer allocation to 512KB to avoid reallocs.
Typical configurations often require >200KB for device state and VMDESC.

Fixes: 8518278a6a (migration: implementation
  of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Message-Id: <20210401092226.102804-2-andrey.gruzdev@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-06 18:56:01 +01:00
Daniel P. Berrangé
cbde7be900 migrate: remove QMP/HMP commands for speed, downtime and cache size
The generic 'migrate_set_parameters' command handle all types of param.

Only the QMP commands were documented in the deprecations page, but the
rationale for deprecating applies equally to HMP, and the replacements
exist. Furthermore the HMP commands are just shims to the QMP commands,
so removing the latter breaks the former unless they get re-implemented.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-03-18 09:22:55 +00:00
Mahmoud Mandour
373969507a migration: Replaced qemu_mutex_lock calls with QEMU_LOCK_GUARD
Replaced various qemu_mutex_lock calls and their respective
qemu_mutex_unlock calls with QEMU_LOCK_GUARD macro. This simplifies
the code by eliminating the respective qemu_mutex_unlock calls.

Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Message-Id: <20210311031538.5325-7-ma.mandourr@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-03-15 20:01:55 +00:00
Dr. David Alan Gilbert
3af8554bd0 migration: Add blocker information
Modify query-migrate so that it has a flag indicating if outbound
migration is blocked, and if it is a list of reasons.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210202135522.127380-2-dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Markus Armbruster
54270c450a migration: Fix a few absurdly defective error messages
migrate_params_check() has a number of error messages of the form

    Parameter 'NAME' expects is invalid, it should be ...

Fix them to something like

    Parameter 'NAME' expects a ...

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210202141734.2488076-5-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Markus Armbruster
8b9407a09f migration: Clean up signed vs. unsigned XBZRLE cache-size
73af8dd8d7 "migration: Make xbzrle_cache_size a migration
parameter" (v2.11.0) made the new parameter unsigned (QAPI type
'size', uint64_t in C).  It neglected to update existing code, which
continues to use int64_t.

migrate_xbzrle_cache_size() returns the new parameter.  Adjust its
return type.

QMP query-migrate-cache-size returns migrate_xbzrle_cache_size().
Adjust its return type.

migrate-set-parameters passes the new parameter to
xbzrle_cache_resize().  Adjust its parameter type.

xbzrle_cache_resize() passes it on to cache_init().  Adjust its
parameter type.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210202141734.2488076-3-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Andrey Gruzdev
8518278a6a migration: implementation of background snapshot thread
Introducing implementation of 'background' snapshot thread
which in overall follows the logic of precopy migration
while internally utilizes completely different mechanism
to 'freeze' vmstate at the start of snapshot creation.

This mechanism is based on userfault_fd with wr-protection
support and is Linux-specific.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210129101407.103458-5-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Andrey Gruzdev
6e8c25b4c6 migration: introduce 'background-snapshot' migration capability
Add new capability to 'qapi/migration.json' schema.
Update migrate_caps_check() to validate enabled capability set
against introduced one. Perform checks for required kernel features
and compatibility with guest memory backends.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210129101407.103458-2-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Eric Blake
95b3a8c8a8 qapi: More complex uses of QAPI_LIST_APPEND
These cases require a bit more thought to review; in each case, the
code was appending to a list, but not with a FOOList **tail variable.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210113221013.390592-6-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Flawed change to qmp_guest_network_get_interfaces() dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-01-28 08:08:45 +01:00
Lukas Straub
b5eea99ec2 migration: Add yank feature
Register yank functions on sockets to shut them down.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <484c6a14cc2506bebedd5a237259b91363ff8f88.1609167865.git.lukasstraub2@web.de>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-01-13 10:21:17 +01:00
Peter Maydell
41192db338 Machine queue, 2020-12-23
Cleanup:
 * qdev code cleanup (Eduardo Habkost)
 
 Bug fix:
 * hostmem: Free host_nodes list right after visited (Keqian Zhu)
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Merge remote-tracking branch 'remotes/ehabkost-gl/tags/machine-next-pull-request' into staging

Machine queue, 2020-12-23

Cleanup:
* qdev code cleanup (Eduardo Habkost)

Bug fix:
* hostmem: Free host_nodes list right after visited (Keqian Zhu)

# gpg: Signature made Wed 23 Dec 2020 21:25:58 GMT
# gpg:                using RSA key 5A322FD5ABC4D3DBACCFD1AA2807936F984DC5A6
# gpg:                issuer "ehabkost@redhat.com"
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>" [full]
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost-gl/tags/machine-next-pull-request:
  bugfix: hostmem: Free host_nodes list right after visited
  qdev: Avoid unnecessary DeviceState* variable at set_prop_arraylen()
  qdev: Rename qdev_get_prop_ptr() to object_field_prop_ptr()
  qdev: Move qdev_prop_tpm declaration to tpm_prop.h
  qdev: Make qdev_class_add_property() more flexible
  qdev: Make PropertyInfo.create return ObjectProperty*
  qdev: Move dev->realized check to qdev_property_set()
  qdev: Wrap getters and setters in separate helpers
  qdev: Add name argument to PropertyInfo.create method
  qdev: Add name parameter to qdev_class_add_property()
  qdev: Avoid using prop->name unnecessarily
  qdev: Get just property name at error_set_from_qdev_prop_error()
  sparc: Use DEFINE_PROP for nwindows property
  qdev: Reuse DEFINE_PROP in all DEFINE_PROP_* macros
  qdev: Move softmmu properties to qdev-properties-system.h

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-01 22:57:15 +00:00
Peter Maydell
1f7c02797f QAPI patches patches for 2020-12-19
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Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2020-12-19' into staging

QAPI patches patches for 2020-12-19

# gpg: Signature made Sat 19 Dec 2020 09:40:05 GMT
# 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-qapi-2020-12-19: (33 commits)
  qobject: Make QString immutable
  block: Use GString instead of QString to build filenames
  keyval: Use GString to accumulate value strings
  json: Use GString instead of QString to accumulate strings
  migration: Replace migration's JSON writer by the general one
  qobject: Factor JSON writer out of qobject_to_json()
  qobject: Factor quoted_str() out of to_json()
  qobject: Drop qstring_get_try_str()
  qobject: Drop qobject_get_try_str()
  Revert "qobject: let object_property_get_str() use new API"
  block: Avoid qobject_get_try_str()
  qmp: Fix tracing of non-string command IDs
  qobject: Move internals to qobject-internal.h
  hw/rdma: Replace QList by GQueue
  Revert "qstring: add qstring_free()"
  qobject: Change qobject_to_json()'s value to GString
  qobject: Use GString instead of QString to accumulate JSON
  qobject: Make qobject_to_json_pretty() take a pretty argument
  monitor: Use GString instead of QString for output buffer
  hmp: Simplify how qmp_human_monitor_command() gets output
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-01 14:33:03 +00:00
Eric Blake
54aa3de72e qapi: Use QAPI_LIST_PREPEND() where possible
Anywhere we create a list of just one item or by prepending items
(typically because order doesn't matter), we can use
QAPI_LIST_PREPEND().  But places where we must keep the list in order
by appending remain open-coded until later patches.

Note that as a side effect, this also performs a cleanup of two minor
issues in qga/commands-posix.c: the old code was performing
 new = g_malloc0(sizeof(*ret));
which 1) is confusing because you have to verify whether 'new' and
'ret' are variables with the same type, and 2) would conflict with C++
compilation (not an actual problem for this file, but makes
copy-and-paste harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-5-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
[Straightforward conflicts due to commit a8aa94b5f8 "qga: update
schema for guest-get-disks 'dependents' field" and commit a10b453a52
"target/mips: Move mips_cpu_add_definition() from helper.c to cpu.c"
resolved.  Commit message tweaked.]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-12-19 10:20:14 +01:00
Eric Blake
eaedde5255 migration: Refactor migrate_cap_add
Instead of taking a list parameter and returning a new head at a
distance, just return the new item for the caller to insert into a
list via QAPI_LIST_PREPEND.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20201113011340.463563-4-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2020-12-19 10:15:08 +01:00
Eduardo Habkost
ce35e2295e qdev: Move softmmu properties to qdev-properties-system.h
Move the property types and property macros implemented in
qdev-properties-system.c to a new qdev-properties-system.h
header.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20201211220529.2290218-16-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-12-18 15:20:17 -05:00
Tuguoyi
36d0fe6516 migration: Don't allow migration if vm is in POSTMIGRATE
The following steps will cause qemu assertion failure:
- pause vm by executing 'virsh suspend'
- create external snapshot of memory and disk using 'virsh snapshot-create-as'
- doing the above operation again will cause qemu crash

The backtrace looks like:
    at /build/qemu-5.0/migration/savevm.c:1401
    at /build/qemu-5.0/migration/savevm.c:1453

When the first migration completes, bs->open_flags will set BDRV_O_INACTIVE
flag by bdrv_inactivate_all(), and during the second migration the
bdrv_inactivate_recurse assert that the bs->open_flags is already
BDRV_O_INACTIVE enabled which cause crash.

As Vladimir suggested, this patch makes migrate_prepare check the state of vm and
return error if it is in RUN_STATE_POSTMIGRATE state.

Signed-off-by: Tuguoyi <tu.guoyi@h3c.com>
Message-Id: <6b704294ad2e405781c38fb38d68c744@h3c.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reported-by: Li Zhang <li.zhang@cloud.ionos.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-12-18 10:08:25 +00:00
Paolo Bonzini
e69d50d621 migration, vl: start migration via qmp_migrate_incoming
Make qemu_start_incoming_migration local to migration/migration.c.
By using the runstate instead of a separate flag, vl need not do
anything to setup deferred incoming migration.

qmp_migrate_incoming also does not need the deferred_incoming flag
anymore, because "-incoming PROTOCOL" will clear the "once" flag
before the main loop starts.  Therefore, later invocations of
the migrate-incoming command will fail with the existing
"The incoming migration has already been started" error message.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:14 -05:00
Paolo Bonzini
e0d17dfd22 vl: move various initialization routines out of qemu_init
Some very simple initialization routines can be nested in existing
subsystem-level functions, do that to simplify qemu_init.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:11 -05:00
Longpeng(Mike)
6ba11211bd migration: handle CANCELLING state in migration_completion()
The following sequence may cause the VM abort during migration:

1. RUN_STATE_RUNNING,MIGRATION_STATUS_ACTIVE

2. before call migration_completion(), we send migrate_cancel
   QMP command, the state machine is changed to:
     RUN_STATE_RUNNING,MIGRATION_STATUS_CANCELLING

3. call migration_completion(), and the state machine is
   switch to: RUN_STATE_RUNNING,MIGRATION_STATUS_COMPLETED

4. call migration_iteration_finish(), because the migration
   status is COMPLETED, so it will try to set the runstate
   to POSTMIGRATE, but RUNNING-->POSTMIGRATE is an invalid
   transition, so abort().

The migration_completion() should not change the migration state
to COMPLETED if it is already changed to CANCELLING.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20201105091726.148-1-longpeng2@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-11-12 15:52:20 +00:00
Chen Qun
a24292830b migration: fix uninitialized variable warning in migrate_send_rp_req_pages()
After the WITH_QEMU_LOCK_GUARD macro is added, the compiler cannot identify
 that the statements in the macro must be executed. As a result, some variables
 assignment statements in the macro may be considered as unexecuted by the compiler.

When the -Wmaybe-uninitialized capability is enabled on GCC9,the compiler showed warning:
migration/migration.c: In function ‘migrate_send_rp_req_pages’:
migration/migration.c:384:8: warning: ‘received’ may be used uninitialized in this function [-Wmaybe-uninitialized]
 384 |     if (received) {
     |        ^

Add a default value for 'received' to prevented the warning.

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201111142203.2359370-6-kuhn.chenqun@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-11-12 14:49:16 +00:00
Kirti Wankhede
3710586caa qapi: Add VFIO devices migration stats in Migration stats
Added amount of bytes transferred to the VM at destination by all VFIO
devices

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01 12:30:51 -07:00
Peter Maydell
d55450df99 migration pull: 2020-10-26
Another go at Peter's postcopy fixes
 
 Cleanups from Bihong Yu and Peter Maydell.
 
 Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20201026a' into staging

migration pull: 2020-10-26

Another go at Peter's postcopy fixes

Cleanups from Bihong Yu and Peter Maydell.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

# gpg: Signature made Mon 26 Oct 2020 16:17:03 GMT
# gpg:                using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full]
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-migration-20201026a:
  migration-test: Only hide error if !QTEST_LOG
  migration/postcopy: Release fd before going into 'postcopy-pause'
  migration: Sync requested pages after postcopy recovery
  migration: Maintain postcopy faulted addresses
  migration: Introduce migrate_send_rp_message_req_pages()
  migration: Pass incoming state into qemu_ufd_copy_ioctl()
  migration: using trace_ to replace DPRINTF
  migration: Delete redundant spaces
  migration: Open brace '{' following function declarations go on the next line
  migration: Do not initialise statics and globals to 0 or NULL
  migration: Add braces {} for if statement
  migration: Open brace '{' following struct go on the same line
  migration: Add spaces around operator
  migration: Don't use '#' flag of printf format
  migration: Do not use C99 // comments
  migration: Drop unused VMSTATE_FLOAT64 support

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-10-27 10:25:42 +00:00
Peter Xu
d246ea5039 migration/postcopy: Release fd before going into 'postcopy-pause'
Logically below race could trigger with the old code:

          test program                        migration thread
          ------------                        ----------------
       wait_until('postcopy-pause')
                                          postcopy_pause()
                                            set_state('postcopy-pause')
       do_postcopy_recover()
         arm s->to_dst_file with new fd
                                            release s->to_dst_file [1]

Here [1] could have released the just-installed recoverying channel.  Then the
migration could hang without really resuming.

Instead, it should be very safe to release the fd before setting the state into
'postcopy-pause', because there's no reason for any other thread to touch it
during 'postcopy-active'.

Dave reported a very rare postcopy recovery hang that the migration-test
program waited for the migration to complete in migrate_postcopy_complete().
We do suspect it's the same thing that we're gonna fix here.  Hard to tell.
However since we've noticed this, fix this irrelevant of the hang report.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201021212721.440373-6-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +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
7a267fc49b migration: Introduce migrate_send_rp_message_req_pages()
This is another layer wrapper for sending a page request to the source VM.  The
new migrate_send_rp_message_req_pages() will be used elsewhere in coming
patches.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20201021212721.440373-3-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
Paolo Bonzini
9f2931bc65 machine: remove deprecated -machine enforce-config-section option
Deprecated since 3.1 and complicates the initialization sequence,
remove it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-26 07:08:39 -04:00
Markus Armbruster
2155ceaf25 error: Remove NULL checks on error_propagate() calls (again)
Patch created mechanically by rerunning:

    $ spatch --sp-file scripts/coccinelle/error_propagate_null.cocci \
             --macro-file scripts/cocci-macro-file.h \
             --use-gitgrep .

Cc: Jens Freimann <jfreimann@redhat.com>
Cc: Hailiang Zhang <zhang.zhanghailiang@huawei.com>
Cc: Juan Quintela <quintela@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200722084048.1726105-4-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-10-09 08:36:23 +02:00
Dr. David Alan Gilbert
1783c00fc9 Revert "migration: Properly destroy variables on incoming side"
This reverts commit c02039a6f3.

This is breaking test 068 that does a loadvm twice.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-28 16:18:02 +01:00
Chuan Zheng
d8053e73fb migration/tls: save hostname into MigrationState
hostname is need in multifd-tls, save hostname into MigrationState.

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Signed-off-by: Yan Jin <jinyan12@huawei.com>
Message-Id: <1600139042-104593-2-git-send-email-zhengchuan@huawei.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-25 12:45:58 +01:00
Laurent Vivier
7590a2ae09 migration: increase max-bandwidth to 128 MiB/s (1 Gib/s)
max-bandwidth is set by default to 32 MiB/s (256 Mib/s)
since 2008 (5bb7910af0).

Most of the CPUs can dirty memory faster than that now,
and this is clearly a problem with POWER where the page
size is 64 kiB and not 4 KiB.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20200921144957.979989-1-lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-25 12:45:58 +01:00
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
Peter Xu
c02039a6f3 migration: Properly destroy variables on incoming side
In migration_incoming_state_destroy(), we've got a few variables that aren't
destroyed properly, namely:

    main_thread_load_event
    postcopy_pause_sem_dst
    postcopy_pause_sem_fault
    rp_mutex

Destroy them properly.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20200908203022.341615-2-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@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
Longpeng(Mike)
9ba3b2baa1 migration: add vsock as data channel support
The vsock channel is more widely use in some new features, for example,
the Nitro/Enclave. It can also be used as the migration channel.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20200806074030.174-3-longpeng2@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Longpeng(Mike)
d658f65c16 migration: unify the framework of socket-type channel
Currently, the only difference of tcp channel and unix channel in
migration/socket.c is the way to build SocketAddress, but socket_parse()
can handle these two types, so use it to instead of tcp_build_address()
and unix_build_address().

The socket-type channel can be further unified based on the up, this
would be helpful for us to add other socket-type channels.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Message-Id: <20200806074030.174-2-longpeng2@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-08-28 13:34:52 +01:00
Max Reitz
31e4c354b3 migration: Add block-bitmap-mapping parameter
This migration parameter allows mapping block node names and bitmap
names to aliases for the purpose of block dirty bitmap migration.

This way, management tools can use different node and bitmap names on
the source and destination and pass the mapping of how bitmaps are to be
transferred to qemu (on the source, the destination, or even both with
arbitrary aliases in the migration stream).

While touching this code, fix a bug where bitmap names longer than 255
bytes would fail an assertion in qemu_put_counted_string().

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200820150725.68687-2-mreitz@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2020-08-21 08:56:09 -05:00
Vladimir Sementsov-Ogievskiy
1499ab0969 migration/block-dirty-bitmap: cancel migration on shutdown
If target is turned off prior to postcopy finished, target crashes
because busy bitmaps are found at shutdown.
Canceling incoming migration helps, as it removes all unfinished (and
therefore busy) bitmaps.

Similarly on source we crash in bdrv_close_all which asserts that all
bdrv states are removed, because bdrv states involved into dirty bitmap
migration are referenced by it. So, we need to cancel outgoing
migration as well.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Message-Id: <20200727194236.19551-17-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-27 15:41:34 -05:00
Vladimir Sementsov-Ogievskiy
d0cccbd118 migration/block-dirty-bitmap: move mutex init to dirty_bitmap_mig_init
No reasons to keep two public init functions.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20200727194236.19551-11-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-27 15:39:59 -05:00
Liao Pingfang
eb9bd46ff6 migration/migration.c: Remove superfluous breaks
Remove superfluous breaks, as there is a "return" before them.

Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-07-13 18:15:36 +02:00
Zheng Chuan
9728ebfb77 migration: fix memory leak in qmp_migrate_set_parameters
"tmp.tls_hostname" and "tmp.tls_creds" allocated by migrate_params_test_apply()
is forgot to free at the end of qmp_migrate_set_parameters(). Fix that.

The leak stack:
Direct leak of 2 byte(s) in 2 object(s) allocated from:
   #0 0xffffb597c20b in __interceptor_malloc (/usr/lib64/libasan.so.4+0xd320b)
   #1 0xffffb52dcb1b in g_malloc (/usr/lib64/libglib-2.0.so.0+0x58b1b)
   #2 0xffffb52f8143 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x74143)
   #3 0xaaaac52447fb in migrate_params_test_apply (/usr/src/debug/qemu-4.1.0/migration/migration.c:1377)
   #4 0xaaaac52fdca7 in qmp_migrate_set_parameters (/usr/src/debug/qemu-4.1.0/qapi/qapi-commands-migration.c:192)
   #5 0xaaaac551d543 in qmp_dispatch (/usr/src/debug/qemu-4.1.0/qapi/qmp-dispatch.c:165)
   #6 0xaaaac52a0a8f in qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:125)
   #7 0xaaaac52a1c7f in monitor_qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:214)
   #8 0xaaaac55cb0cf in aio_bh_call (/usr/src/debug/qemu-4.1.0/util/async.c:117)
   #9 0xaaaac55d4543 in aio_bh_poll (/usr/src/debug/qemu-4.1.0/util/aio-posix.c:459)
   #10 0xaaaac55cae0f in aio_dispatch (/usr/src/debug/qemu-4.1.0/util/async.c:268)
   #11 0xffffb52d6a7b in g_main_context_dispatch (/usr/lib64/libglib-2.0.so.0+0x52a7b)
   #12 0xaaaac55d1e3b(/usr/bin/qemu-kvm-4.1.0+0x1622e3b)
   #13 0xaaaac4e314bb(/usr/bin/qemu-kvm-4.1.0+0xe824bb)
   #14 0xaaaac47f45ef(/usr/bin/qemu-kvm-4.1.0+0x8455ef)
   #15 0xffffb4bfef3f in __libc_start_main (/usr/lib64/libc.so.6+0x23f3f)
   #16 0xaaaac47ffacb(/usr/bin/qemu-kvm-4.1.0+0x850acb)

Direct leak of 2 byte(s) in 2 object(s) allocated from:
   #0 0xffffb597c20b in __interceptor_malloc (/usr/lib64/libasan.so.4+0xd320b)
   #1 0xffffb52dcb1b in g_malloc (/usr/lib64/libglib-2.0.so.0+0x58b1b)
   #2 0xffffb52f8143 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x74143)
   #3 0xaaaac5244893 in migrate_params_test_apply (/usr/src/debug/qemu-4.1.0/migration/migration.c:1382)
   #4 0xaaaac52fdca7 in qmp_migrate_set_parameters (/usr/src/debug/qemu-4.1.0/qapi/qapi-commands-migration.c:192)
   #5 0xaaaac551d543 in qmp_dispatch (/usr/src/debug/qemu-4.1.0/qapi/qmp-dispatch.c)
   #6 0xaaaac52a0a8f in qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:125)
   #7 0xaaaac52a1c7f in monitor_qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:214)
   #8 0xaaaac55cb0cf in aio_bh_call (/usr/src/debug/qemu-4.1.0/util/async.c:117)
   #9 0xaaaac55d4543 in aio_bh_poll (/usr/src/debug/qemu-4.1.0/util/aio-posix.c:459)
   #10 0xaaaac55cae0f in in aio_dispatch (/usr/src/debug/qemu-4.1.0/util/async.c:268)
   #11 0xffffb52d6a7b in g_main_context_dispatch (/usr/lib64/libglib-2.0.so.0+0x52a7b)
   #12 0xaaaac55d1e3b(/usr/bin/qemu-kvm-4.1.0+0x1622e3b)
   #13 0xaaaac4e314bb(/usr/bin/qemu-kvm-4.1.0+0xe824bb)
   #14 0xaaaac47f45ef (/usr/bin/qemu-kvm-4.1.0+0x8455ef)
   #15 0xffffb4bfef3f in __libc_start_main (/usr/lib64/libc.so.6+0x23f3f)
   #16 0xaaaac47ffacb(/usr/bin/qemu-kvm-4.1.0+0x850acb)

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: KeQian Zhu <zhukeqian1@huawei.com>
Reviewed-by: HaiLiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-07-13 18:13:49 +02:00
Claudio Fontana
b0c3cf9407 cpu-throttle: new module, extracted from cpus.c
move the vcpu throttling functionality into its own module.

This functionality is not specific to any accelerator,
and it is used currently by migration to slow down guests to try to
have migrations converge, and by the cocoa MacOS UI to throttle speed.

cpu-throttle contains the controls to adjust and inspect throttle
settings, start (set) and stop vcpu throttling, and the throttling
function itself that is run periodically on vcpus to make them take a nap.

Execution of the throttling function on all vcpus is triggered by a timer,
registered at module initialization.

No functionality change.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20200629093504.3228-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10 18:04:49 -04:00
David Hildenbrand
18b1d3c952 migration/colo: Use ram_block_discard_disable()
COLO will copy all memory in a RAM block, disable discarding of RAM.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Lukas Straub <lukasstraub2@web.de>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Hailiang Zhang <zhang.zhanghailiang@huawei.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: <20200626072248.78761-10-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
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
Markus Armbruster
2194abd623 qdev: qdev_create(), qdev_try_create() are now unused, drop
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-31-armbru@redhat.com>
2020-06-15 22:05:28 +02:00
Lukas Straub
773861274a migration/migration.c: Fix hang in ram_save_host_page
migration_rate_limit will erroneously ratelimit a shutdown socket,
which causes the migration thread to hang in ram_save_host_page
if the socket is shutdown.

Fix this by explicitly testing if the socket has errors or was
shutdown in migration_rate_limit.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Message-Id: <e79085bbe2d46dfa007dd41820194d5e2d4fcd80.1590007004.git.lukasstraub2@web.de>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-06-01 18:44:27 +01:00
Wei Wang
e460a4b1a4 migration/xbzrle: add encoding rate
Users may need to check the xbzrle encoding rate to know if the guest
memory is xbzrle encoding-friendly, and dynamically turn off the
encoding if the encoding rate is low.

Signed-off-by: Yi Sun <yi.y.sun@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Message-Id: <1588208375-19556-1-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00
Keqian Zhu
cbbf818224 migration/throttle: Add cpu-throttle-tailslow migration parameter
At the tail stage of throttling, the Guest is very sensitive to
CPU percentage while the @cpu-throttle-increment is excessive
usually at tail stage.

If this parameter is true, we will compute the ideal CPU percentage
used by the Guest, which may exactly make the dirty rate match the
dirty rate threshold. Then we will choose a smaller throttle increment
between the one specified by @cpu-throttle-increment and the one
generated by ideal CPU percentage.

Therefore, it is compatible to traditional throttling, meanwhile
the throttle increment won't be excessive at tail stage. This may
make migration time longer, and is disabled by default.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Message-Id: <20200413101508.54793-1-zhukeqian1@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00
Mao Zhongyi
7ac5529afb migration: move the units of migrate parameters from milliseconds to ms
Signed-off-by: Mao Zhongyi <maozhongyi@cmss.chinamobile.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <474bb6cf67defb8be9de5035c11aee57a680557a.1585641083.git.maozhongyi@cmss.chinamobile.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00
Mao Zhongyi
2ee30cf078 migration/migration: improve error reporting for migrate parameters
use QERR_INVALID_PARAMETER_VALUE instead of
"Parameter '%s' expects" for consistency.

Signed-off-by: Mao Zhongyi <maozhongyi@cmss.chinamobile.com>
Message-Id: <4ce71da4a5f98ad6ead0806ec71043473dcb4c07.1585641083.git.maozhongyi@cmss.chinamobile.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00