Commit Graph

861 Commits

Author SHA1 Message Date
Peter Xu
d1b8eadbc4 migration: introduce SaveVMHandlers.resume_prepare
This is hook function to be called when a postcopy migration wants to
resume from a failure. For each module, it should provide its own
recovery logic before we switch to the postcopy-active state.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-16-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:55 +02:00
Peter Xu
13955b89ce migration: new message MIG_RP_MSG_RESUME_ACK
Creating new message to reply for MIG_CMD_POSTCOPY_RESUME. One uint32_t
is used as payload to let the source know whether destination is ready
to continue the migration.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-15-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:53 +02:00
Peter Xu
3f5875eca5 migration: new cmd MIG_CMD_POSTCOPY_RESUME
Introducing this new command to be sent when the source VM is ready to
resume the paused migration.  What the destination does here is
basically release the fault thread to continue service page faults.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-14-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:52 +02:00
Peter Xu
a335debb35 migration: new message MIG_RP_MSG_RECV_BITMAP
Introducing new return path message MIG_RP_MSG_RECV_BITMAP to send
received bitmap of ramblock back to source.

This is the reply message of MIG_CMD_RECV_BITMAP, it contains not only
the header (including the ramblock name), and it was appended with the
whole ramblock received bitmap on the destination side.

When the source receives such a reply message (MIG_RP_MSG_RECV_BITMAP),
it parses it, convert it to the dirty bitmap by inverting the bits.

One thing to mention is that, when we send the recv bitmap, we are doing
these things in extra:

- converting the bitmap to little endian, to support when hosts are
  using different endianess on src/dst.

- do proper alignment for 8 bytes, to support when hosts are using
  different word size (32/64 bits) on src/dst.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-13-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:51 +02:00
Peter Xu
f25d42253c migration: new cmd MIG_CMD_RECV_BITMAP
Add a new vm command MIG_CMD_RECV_BITMAP to request received bitmap for
one ramblock.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-12-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:49 +02:00
Peter Xu
d96c9e8d78 migration: wakeup dst ram-load-thread for recover
On the destination side, we cannot wake up all the threads when we got
reconnected. The first thing to do is to wake up the main load thread,
so that we can continue to receive valid messages from source again and
reply when needed.

At this point, we switch the destination VM state from postcopy-paused
back to postcopy-recover.

Now we are finally ready to do the resume logic.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-11-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:48 +02:00
Peter Xu
135b87b4f0 migration: new state "postcopy-recover"
Introducing new migration state "postcopy-recover". If a migration
procedure is paused and the connection is rebuilt afterward
successfully, we'll switch the source VM state from "postcopy-paused" to
the new state "postcopy-recover", then we'll do the resume logic in the
migration thread (along with the return path thread).

This patch only do the state switch on source side. Another following up
patch will handle the state switching on destination side using the same
status bit.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-10-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

---
s/2.11/2.13/
2018-05-15 20:56:30 +02:00
Peter Xu
d3e35b8f62 migration: rebuild channel on source
This patch detects the "resume" flag of migration command, rebuild the
channels only if the flag is set.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-9-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:55:19 +02:00
Peter Xu
7a4da28b26 qmp: hmp: add migrate "resume" option
It will be used when we want to resume one paused migration.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-8-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
s/2.12/2.13/
2018-05-15 20:54:49 +02:00
Peter Xu
3a7804c306 migration: allow fault thread to pause
Allows the fault thread to stop handling page faults temporarily. When
network failure happened (and if we expect a recovery afterwards), we
should not allow the fault thread to continue sending things to source,
instead, it should halt for a while until the connection is rebuilt.

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

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-7-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
14b1742eaa migration: allow src return path to pause
Let the thread pause for network issues.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-6-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
b411b844fb migration: allow dst vm pause on postcopy
When there is IO error on the incoming channel (e.g., network down),
instead of bailing out immediately, we allow the dst vm to switch to the
new POSTCOPY_PAUSE state. Currently it is still simple - it waits the
new semaphore, until someone poke it for another attempt.

One note is that here on ram loading thread we cannot detect the
POSTCOPY_ACTIVE state, but we need to detect the more specific
POSTCOPY_INCOMING_RUNNING state, to make sure we have already loaded all
the device states.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-5-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
b23c2ade25 migration: implement "postcopy-pause" src logic
Now when network down for postcopy, the source side will not fail the
migration. Instead we convert the status into this new paused state, and
we will try to wait for a rescue in the future.

If a recovery is detected, migration_thread() will reset its local
variables to prepare for that.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-4-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
a688d2c1ab migration: new postcopy-pause state
Introducing a new state "postcopy-paused", which can be used when the
postcopy migration is paused. It is targeted for postcopy network
failure recovery.

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: <20180502104740.12123-3-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
e89f5ff2c3 migration: let incoming side use thread context
The old incoming migration is running in main thread and default
gcontext.  With the new qio_channel_add_watch_full() we can now let it
run in the thread's own gcontext (if there is one).

Currently this patch does nothing alone.  But when any of the incoming
migration is run in another iothread (e.g., the upcoming migrate-recover
command), this patch will bind the incoming logic to the iothread
instead of the main thread (which may already get page faulted and
hanged).

RDMA is not considered for now since it's not even using the QIO watch
framework at all.

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: <20180502104740.12123-2-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
8c4598f2b1 migration: Define MultifdRecvParams sooner
Once there, we don't need the struct names anywhere, just the
typedefs.  And now also document all fields.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
af8b7d2b09 migration: Transmit initial package through the multifd channels
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

--

Be network agnostic.
Add error checking for all values.
2018-05-15 20:24:27 +02:00
Juan Quintela
36c2f8be2c migration: Delay start of migration main routines
We need to make sure that we have started all the multifd threads.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
60df2d4ae5 migration: Create multifd channels
In both sides.  We still don't transmit anything through them.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
3854956ad7 migration: Export functions to create send channels
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
62c1e0ca73 migration: Be sure all recv channels are created
We need them before we start migration.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
667707078d migration: terminate_* can be called for other threads
Once there, make  count field to always be accessed with atomic
operations.  To make blocking operations, we need to know that the
thread is running, so create a bool to indicate that.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

--

Once here, s/terminate_multifd_*-threads/multifd_*_terminate_threads/
This is consistente with every other function
2018-05-15 20:24:27 +02:00
Juan Quintela
71bb07dbfc migration: Introduce multifd_recv_new_channel()
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-15 20:24:27 +02:00
Juan Quintela
7a169d745c migration: Set error state in case of error
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Xiao Guangrong
701b1876c0 migration: fix saving normal page even if it's been compressed
Fix the bug introduced by da3f56cb2e (migration: remove
ram_save_compressed_page()), It should be 'return' rather than
'res'

Sorry for this stupid mistake :(

Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180428081045.8878-1-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:00 +02:00
Peter Maydell
c8b7e627b4 nbd patches for 2018-05-04
- Vladimir Sementsov-Ogievskiy: 0/2 fix coverity bugs
 - Eric Blake: nbd/client: Fix error messages during NBD_INFO_BLOCK_SIZE
 - Eric Blake: nbd/client: Relax handling of large NBD_CMD_BLOCK_STATUS reply
 -----BEGIN PGP SIGNATURE-----
 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg
 
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Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2018-05-04' into staging

nbd patches for 2018-05-04

- Vladimir Sementsov-Ogievskiy: 0/2 fix coverity bugs
- Eric Blake: nbd/client: Fix error messages during NBD_INFO_BLOCK_SIZE
- Eric Blake: nbd/client: Relax handling of large NBD_CMD_BLOCK_STATUS reply

# gpg: Signature made Fri 04 May 2018 14:25:55 BST
# gpg:                using RSA key A7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>"
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>"
# gpg:                 aka "[jpeg image of size 6874]"
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2018-05-04:
  nbd/client: Relax handling of large NBD_CMD_BLOCK_STATUS reply
  nbd/client: Fix error messages during NBD_INFO_BLOCK_SIZE
  migration/block-dirty-bitmap: fix memory leak in dirty_bitmap_load_bits
  nbd/client: fix nbd_negotiate_simple_meta_context

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-05-04 14:42:46 +01:00
Vladimir Sementsov-Ogievskiy
16a2227893 migration/block-dirty-bitmap: fix memory leak in dirty_bitmap_load_bits
Release buf on error path too.

Bug was introduced in b35ebdf076 "migration: add postcopy
migration of dirty bitmaps" with the whole function.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20180427142002.21930-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-05-04 08:23:26 -05:00
Marc-André Lureau
cb3e7f08ae qobject: Replace qobject_incref/QINCREF qobject_decref/QDECREF
Now that we can safely call QOBJECT() on QObject * as well as its
subtypes, we can have macros qobject_ref() / qobject_unref() that work
everywhere instead of having to use QINCREF() / QDECREF() for QObject
and qobject_incref() / qobject_decref() for its subtypes.

The replacement is mechanical, except I broke a long line, and added a
cast in monitor_qmp_cleanup_req_queue_locked().  Unlike
qobject_decref(), qobject_unref() doesn't accept void *.

Note that the new macros evaluate their argument exactly once, thus no
need to shout them.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180419150145.24795-4-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased, semantic conflict resolved, commit message improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04 08:27:53 +02:00
Xiao Guangrong
da3f56cb2e migration: remove ram_save_compressed_page()
Now, we can reuse the path in ram_save_page() to post the page out
as normal, then the only thing remained in ram_save_compressed_page()
is compression that we can move it out to the caller

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-11-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:14 +01:00
Xiao Guangrong
65dacaa04f migration: introduce save_normal_page()
It directly sends the page to the stream neither checking zero nor
using xbzrle or compression

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-10-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:12 +01:00
Xiao Guangrong
d7400a3409 migration: move calling save_zero_page to the common place
save_zero_page() is always our first approach to try, move it to
the common place before calling ram_save_compressed_page
and ram_save_page

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-9-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:11 +01:00
Xiao Guangrong
a8ec91f941 migration: move calling control_save_page to the common place
The function is called by both ram_save_page and ram_save_target_page,
so move it to the common caller to cleanup the code

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-8-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:10 +01:00
Xiao Guangrong
1faa5665c0 migration: move some code to ram_save_host_page
Move some code from ram_save_target_page() to ram_save_host_page()
to make it be more readable for latter patches that dramatically
clean ram_save_target_page() up

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-7-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:09 +01:00
Xiao Guangrong
059ff0fb29 migration: introduce control_save_page()
Abstract the common function control_save_page() to cleanup the code,
no logic is changed

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-6-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:09 +01:00
Xiao Guangrong
34ab9e9743 migration: detect compression and decompression errors
Currently the page being compressed is allowed to be updated by
the VM on the source QEMU, correspondingly the destination QEMU
just ignores the decompression error. However, we completely miss
the chance to catch real errors, then the VM is corrupted silently

To make the migration more robuster, we copy the page to a buffer
first to avoid it being written by VM, then detect and handle the
errors of both compression and decompression errors properly

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-5-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:08 +01:00
Xiao Guangrong
797ca154b4 migration: stop decompression to allocate and free memory frequently
Current code uses uncompress() to decompress memory which manages
memory internally, that causes huge memory is allocated and freed
very frequently, more worse, frequently returning memory to kernel
will flush TLBs

So, we maintain the memory by ourselves and reuse it for each
decompression

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-4-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:07 +01:00
Xiao Guangrong
dcaf446ebd migration: stop compression to allocate and free memory frequently
Current code uses compress2() to compress memory which manages memory
internally, that causes huge memory is allocated and freed very
frequently

More worse, frequently returning memory to kernel will flush TLBs
and trigger invalidation callbacks on mmu-notification which
interacts with KVM MMU, that dramatically reduce the performance
of VM

So, we maintain the memory by ourselves and reuse it for each
compression

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-3-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:06 +01:00
Xiao Guangrong
263a289ae6 migration: stop compressing page in migration thread
As compression is a heavy work, do not do it in migration thread,
instead, we post it out as a normal page

Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-2-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:04:05 +01:00
Alexey Perevalov
65ace06045 migration: add postcopy total blocktime into query-migrate
Postcopy total blocktime is available on destination side only.
But query-migrate was possible only for source. This patch
adds ability to call query-migrate on destination.
To be able to see postcopy blocktime, need to request postcopy-blocktime
capability.

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

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

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

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

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

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

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

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

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

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

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

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

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1521742647-25550-3-git-send-email-a.perevalov@samsung.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:02:12 +01:00
Alexey Perevalov
f22f928ec9 migration: introduce postcopy-blocktime capability
Right now it could be used on destination side to
enable vCPU blocktime calculation for postcopy live migration.
vCPU blocktime - it's time since vCPU thread was put into
interruptible sleep, till memory page was copied and thread awake.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1521742647-25550-2-git-send-email-a.perevalov@samsung.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-25 18:02:12 +01:00
Dr. David Alan Gilbert
a18a73d747 Revert "migration: Don't activate block devices if using -S"
This reverts commit 0746a92612.
Discussion with kwolf suggests this is actually an API change that
we need to gate on a capability.  Push to 2.13.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-04-10 15:28:42 +01:00
Dr. David Alan Gilbert
0746a92612 migration: Don't activate block devices if using -S
Activating the block devices causes the locks to be taken on
the backing file.  If we're running with -S and the destination libvirt
hasn't started the destination with 'cont', it's expecting the locks are
still untaken.

Don't activate the block devices if we're not going to autostart the VM;
'cont' already will do that anyway.

bz: https://bugzilla.redhat.com/show_bug.cgi?id=1560854
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180328170207.49512-1-dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-29 14:53:16 +01:00
Marc-André Lureau
fc6008f37a migration: fix pfd leak
Fix leak spotted by ASAN:

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

Regression introduced with commit 00fa4fc85b.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180321113644.21899-1-marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-29 14:53:16 +01:00
Dr. David Alan Gilbert
09576e74db migration: Fix block migration flag case
Fix the case where when a migration with a bad protocol is tried,
we leave the block migration capability set.

(This is a cut down version of my 'migration: Fix block failure cases'
where it's other case was fixed by Peter's dd0ee30cae )

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180316202114.32345-1-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-23 18:24:11 +00:00
Peter Lieven
b47d1e9fe0 migration/block: compare only read blocks against the rate limiter
only read_done blocks are in the queued to be flushed to the migration
stream. submitted blocks are still in flight.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1520507908-16743-6-git-send-email-pl@kamp.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-23 16:45:18 +00:00
Peter Lieven
44815334e1 migration/block: limit the number of parallel I/O requests
the current implementation submits up to 512 I/O requests in parallel
which is much to high especially for a background task.
This patch adds a maximum limit of 16 I/O requests that can
be submitted in parallel to avoid monopolizing the I/O device.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1520507908-16743-5-git-send-email-pl@kamp.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-23 16:45:03 +00:00
Lidong Chen
e8a0f2f9a1 migration: Fix rate limiting issue on RDMA migration
RDMA migration implement save_page function for QEMUFile, but
ram_control_save_page do not increase bytes_xfer. So when doing
RDMA migration, it will use whole bandwidth.

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Message-Id: <1520692378-1835-1-git-send-email-lidongchen@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-23 16:37:15 +00:00
Daniel P. Berrange
bdd847a026 migration: convert socket server to QIONetListener
Instead of creating a QIOChannelSocket directly for the migration
server socket, use a QIONetListener. This provides the ability
to listen on multiple sockets at the same time, so enables
full support for IPv4/IPv6 dual stack.

For example,   '$QEMU -incoming tcp::9000' now correctly listens
on both 0.0.0.0 and :: at the same time, instead of only on 0.0.0.0.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20180312141714.7223-1-berrange@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-23 16:27:24 +00:00
Peter Maydell
ed627b2ad3 virtio,vhost,pci,pc: features, cleanups
SRAT tables for DIMM devices
 new virtio net flags for speed/duplex
 post-copy migration support in vhost
 cleanups in pci
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,vhost,pci,pc: features, cleanups

SRAT tables for DIMM devices
new virtio net flags for speed/duplex
post-copy migration support in vhost
cleanups in pci

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

# gpg: Signature made Tue 20 Mar 2018 14:40:43 GMT
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (51 commits)
  postcopy shared docs
  libvhost-user: Claim support for postcopy
  postcopy: Allow shared memory
  vhost: Huge page align and merge
  vhost+postcopy: Wire up POSTCOPY_END notify
  vhost-user: Add VHOST_USER_POSTCOPY_END message
  libvhost-user: mprotect & madvises for postcopy
  vhost+postcopy: Call wakeups
  vhost+postcopy: Add vhost waker
  postcopy: postcopy_notify_shared_wake
  postcopy: helper for waking shared
  vhost+postcopy: Resolve client address
  postcopy-ram: add a stub for postcopy_request_shared_page
  vhost+postcopy: Helper to send requests to source for shared pages
  vhost+postcopy: Stash RAMBlock and offset
  vhost+postcopy: Send address back to qemu
  libvhost-user+postcopy: Register new regions with the ufd
  migration/ram: ramblock_recv_bitmap_test_byte_offset
  postcopy+vhost-user: Split set_mem_table for postcopy
  vhost+postcopy: Transmit 'listen' to slave
  ...

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

# Conflicts:
#	scripts/update-linux-headers.sh
2018-03-20 15:48:34 +00:00
Dr. David Alan Gilbert
29d8fa7f73 postcopy: Allow shared memory
Now that we have the mechanisms in here, allow shared memory in a
postcopy.

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

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

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

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

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

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

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

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:29 +02:00
Dr. David Alan Gilbert
1cba9f6e66 migration/ram: ramblock_recv_bitmap_test_byte_offset
Utility for testing the map when you already know the offset
in the RAMBlock.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:28 +02:00
Dr. David Alan Gilbert
6864a7b5ac vhost+postcopy: Transmit 'listen' to slave
Notify the vhost-user slave on reception of the 'postcopy-listen'
event from the source.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:28 +02:00
Dr. David Alan Gilbert
00fa4fc85b postcopy: Allow registering of fd handler
Allow other userfaultfd's to be registered into the fault thread
so that handlers for shared memory can get responses.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:28 +02:00
Dr. David Alan Gilbert
d3dff7a5a1 vhost-user: Add 'VHOST_USER_POSTCOPY_ADVISE' message
Wire up a notifier to send a VHOST_USER_POSTCOPY_ADVISE
message on an incoming advise.

Later patches will fill in the behaviour/contents of the
message.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:27 +02:00
Dr. David Alan Gilbert
1693c64c27 postcopy: Add notifier chain
Add a notifier chain for postcopy with a 'reason' flag
and an opportunity for a notifier member to return an error.

Call it when enabling postcopy.

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

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

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

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:27 +02:00
Peter Maydell
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Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

# gpg: Signature made Tue 13 Mar 2018 21:11:43 GMT
# gpg:                using RSA key 7DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>"
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  iotests: add dirty bitmap postcopy test
  iotests: add dirty bitmap migration test
  migration: add postcopy migration of dirty bitmaps
  migration: allow qmp command migrate-start-postcopy for any postcopy
  migration: add is_active_iterate handler
  migration/qemu-file: add qemu_put_counted_string()
  migration: include migrate_dirty_bitmaps in migrate_postcopy
  qapi: add dirty-bitmaps migration capability
  migration: introduce postcopy-only pending
  dirty-bitmap: add locked state
  block/dirty-bitmap: add _locked version of bdrv_reclaim_dirty_bitmap
  block/dirty-bitmap: fix locking in bdrv_reclaim_dirty_bitmap
  block/dirty-bitmap: add bdrv_dirty_bitmap_enable_successor()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-16 14:15:18 +00:00
Vladimir Sementsov-Ogievskiy
b35ebdf076 migration: add postcopy migration of dirty bitmaps
Postcopy migration of dirty bitmaps. Only named dirty bitmaps are migrated.

If destination qemu is already containing a dirty bitmap with the same name
as a migrated bitmap (for the same node), then, if their granularities are
the same the migration will be done, otherwise the error will be generated.

If destination qemu doesn't contain such bitmap it will be created.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-12-vsementsov@virtuozzo.com
[Changed '+' to '*' as per list discussion. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2018-03-13 17:06:09 -04:00
Vladimir Sementsov-Ogievskiy
16b0fd3252 migration: allow qmp command migrate-start-postcopy for any postcopy
Allow migrate-start-postcopy for any postcopy type

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-11-vsementsov@virtuozzo.com
2018-03-13 17:06:03 -04:00
Vladimir Sementsov-Ogievskiy
c865d84872 migration: add is_active_iterate handler
Only-postcopy savevm states (dirty-bitmap) don't need live iteration, so
to disable them and stop transporting empty sections there is a new
savevm handler.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-10-vsementsov@virtuozzo.com
2018-03-13 17:05:58 -04:00
Vladimir Sementsov-Ogievskiy
f0d64cb729 migration/qemu-file: add qemu_put_counted_string()
Add function opposite to qemu_get_counted_string.
qemu_put_counted_string puts one-byte length of the string (string
should not be longer than 255 characters), and then it puts the string,
without last zero byte.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-9-vsementsov@virtuozzo.com
2018-03-13 17:05:55 -04:00
Vladimir Sementsov-Ogievskiy
dd6bb91450 migration: include migrate_dirty_bitmaps in migrate_postcopy
Enable postcopy if dirty bitmap migration is enabled.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-8-vsementsov@virtuozzo.com
2018-03-13 17:05:51 -04:00
Vladimir Sementsov-Ogievskiy
55efc8c2ff qapi: add dirty-bitmaps migration capability
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-7-vsementsov@virtuozzo.com
2018-03-13 17:05:45 -04:00
Vladimir Sementsov-Ogievskiy
4799502640 migration: introduce postcopy-only pending
There would be savevm states (dirty-bitmap) which can migrate only in
postcopy stage. The corresponding pending is introduced here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-6-vsementsov@virtuozzo.com
2018-03-13 17:05:41 -04:00
Pavel Dovgalyuk
377b21ccea replay: fix save/load vm for non-empty queue
This patch does not allows saving/loading vmstate when
replay events queue is not empty. There is no reliable
way to save events queue, because it describes internal
coroutine state. Therefore saving and loading operations
should be deferred to another record/replay step.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20180227095214.1060.32939.stgit@pasha-VirtualBox>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
2018-03-12 16:12:50 +01:00
Peter Xu
dd0ee30cae migration: fix applying wrong capabilities
When setting migration capabilities via QMP/HMP, we'll apply them even
if the capability check failed.  Fix it.

Fixes: 4a84214ebe ("migration: provide migrate_caps_check()", 2017-07-18)
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180305094938.31374-1-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-09 17:39:25 +00:00
Peter Lieven
ef9c5160a1 migration/block: rename MAX_INFLIGHT_IO to MAX_IO_BUFFERS
this actually limits (as the original commit mesage suggests) the
number of I/O buffers that can be allocated and not the number
of parallel (inflight) I/O requests.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1520507908-16743-4-git-send-email-pl@kamp.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-09 17:39:25 +00:00
Peter Lieven
86b124bc76 migration/block: reset dirty bitmap before read in bulk phase
Reset the dirty bitmap before reading to make sure we don't miss
any new data.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1520507908-16743-3-git-send-email-pl@kamp.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-09 17:39:25 +00:00
Peter Lieven
b255734531 migration: do not transfer ram during bulk storage migration
this patch makes the bulk phase of a block migration to take
place before we start transferring ram. As the bulk block migration
can take a long time its pointless to transfer ram during that phase.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1520507908-16743-2-git-send-email-pl@kamp.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-09 17:39:25 +00:00
Marc-André Lureau
ab105cc138 migration: fix minor finalize leak
Spotted thanks to ASAN:
QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 tests/migration-test -p /x86_64/migration/bad_dest

==30302==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 48 byte(s) in 1 object(s) allocated from:
    #0 0x7f60efba1a38 in __interceptor_calloc (/lib64/libasan.so.4+0xdea38)
    #1 0x7f60eef3cf75 in g_malloc0 ../glib/gmem.c:124
    #2 0x55ca9094702c in error_copy /home/elmarco/src/qemu/util/error.c:203
    #3 0x55ca9037a30f in migrate_set_error /home/elmarco/src/qemu/migration/migration.c:1139
    #4 0x55ca9037a462 in migrate_fd_error /home/elmarco/src/qemu/migration/migration.c:1150
    #5 0x55ca9038162b in migrate_fd_connect /home/elmarco/src/qemu/migration/migration.c:2411
    #6 0x55ca90386e41 in migration_channel_connect /home/elmarco/src/qemu/migration/channel.c:81
    #7 0x55ca9038335e in socket_outgoing_migration /home/elmarco/src/qemu/migration/socket.c:85
    #8 0x55ca9083dd3a in qio_task_complete /home/elmarco/src/qemu/io/task.c:142
    #9 0x55ca9083d6cc in gio_task_thread_result /home/elmarco/src/qemu/io/task.c:88
    #10 0x7f60eef37317 in g_idle_dispatch ../glib/gmain.c:5552
    #11 0x7f60eef3490b in g_main_dispatch ../glib/gmain.c:3182
    #12 0x7f60eef357ac in g_main_context_dispatch ../glib/gmain.c:3847
    #13 0x55ca90927231 in glib_pollfds_poll /home/elmarco/src/qemu/util/main-loop.c:214
    #14 0x55ca90927420 in os_host_main_loop_wait /home/elmarco/src/qemu/util/main-loop.c:261
    #15 0x55ca909275fa in main_loop_wait /home/elmarco/src/qemu/util/main-loop.c:515
    #16 0x55ca8fc1c2a4 in main_loop /home/elmarco/src/qemu/vl.c:1942
    #17 0x55ca8fc2eb3a in main /home/elmarco/src/qemu/vl.c:4724
    #18 0x7f60e4082009 in __libc_start_main (/lib64/libc.so.6+0x21009)

Indirect leak of 45 byte(s) in 1 object(s) allocated from:
    #0 0x7f60efba1850 in malloc (/lib64/libasan.so.4+0xde850)
    #1 0x7f60eef3cf0c in g_malloc ../glib/gmem.c:94
    #2 0x7f60eef3d1cf in g_malloc_n ../glib/gmem.c:331
    #3 0x7f60eef596eb in g_strdup ../glib/gstrfuncs.c:363
    #4 0x55ca90947085 in error_copy /home/elmarco/src/qemu/util/error.c:204
    #5 0x55ca9037a30f in migrate_set_error /home/elmarco/src/qemu/migration/migration.c:1139
    #6 0x55ca9037a462 in migrate_fd_error /home/elmarco/src/qemu/migration/migration.c:1150
    #7 0x55ca9038162b in migrate_fd_connect /home/elmarco/src/qemu/migration/migration.c:2411
    #8 0x55ca90386e41 in migration_channel_connect /home/elmarco/src/qemu/migration/channel.c:81
    #9 0x55ca9038335e in socket_outgoing_migration /home/elmarco/src/qemu/migration/socket.c:85
    #10 0x55ca9083dd3a in qio_task_complete /home/elmarco/src/qemu/io/task.c:142
    #11 0x55ca9083d6cc in gio_task_thread_result /home/elmarco/src/qemu/io/task.c:88
    #12 0x7f60eef37317 in g_idle_dispatch ../glib/gmain.c:5552
    #13 0x7f60eef3490b in g_main_dispatch ../glib/gmain.c:3182
    #14 0x7f60eef357ac in g_main_context_dispatch ../glib/gmain.c:3847
    #15 0x55ca90927231 in glib_pollfds_poll /home/elmarco/src/qemu/util/main-loop.c:214
    #16 0x55ca90927420 in os_host_main_loop_wait /home/elmarco/src/qemu/util/main-loop.c:261
    #17 0x55ca909275fa in main_loop_wait /home/elmarco/src/qemu/util/main-loop.c:515
    #18 0x55ca8fc1c2a4 in main_loop /home/elmarco/src/qemu/vl.c:1942
    #19 0x55ca8fc2eb3a in main /home/elmarco/src/qemu/vl.c:4724
    #20 0x7f60e4082009 in __libc_start_main (/lib64/libc.so.6+0x21009)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180306170959.3921-1-marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-03-09 17:39:25 +00:00
Peter Xu
1939ccdaa6 qio: non-default context for TLS handshake
A new parameter "context" is added to qio_channel_tls_handshake() is to
allow the TLS to be run on a non-default context.  Still, no functional
change.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06 10:19:07 +00:00
Peter Xu
8005fdd8fa qio: non-default context for async conn
We have worked on qio_task_run_in_thread() already.  Further, let
all the qio channel APIs use that context.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-03-06 10:19:06 +00:00
Markus Armbruster
112ed241f5 qapi: Empty out qapi-schema.json
The previous commit improved compile time by including less of the
generated QAPI headers.  This is impossible for stuff defined directly
in qapi-schema.json, because that ends up in headers that that pull in
everything.

Move everything but include directives from qapi-schema.json to new
sub-module qapi/misc.json, then include just the "misc" shard where
possible.

It's possible everywhere, except:

* monitor.c needs qmp-command.h to get qmp_init_marshal()

* monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need
  qapi-event.h to get enum QAPIEvent

Perhaps we'll get rid of those some other day.

Adding a type to qapi/migration.json now recompiles some 120 instead
of 2300 out of 5100 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-25-armbru@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Markus Armbruster
9af2398977 Include less of the generated modular QAPI headers
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.

The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h.  Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.

To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects.  The next commit will
improve it further.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Peter Xu
3e0c8050eb migration: pass MigrationState to migrate_init()
Let the callers take the object, then pass it to migrate_init().

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-12-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:37:09 +00:00
Peter Xu
d6208e35e4 migration: allow send_rq to fail
We will not allow failures to happen when sending data from destination
to source via the return path. However it is possible that there can be
errors along the way.  This patch allows the migrate_send_rp_message()
to return error when it happens, and further extended it to
migrate_send_rp_req_pages().

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-9-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:36:52 +00:00
Peter Xu
9ab7ef9b66 migration: provide postcopy_fault_thread_notify()
A general helper to notify the fault thread.

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

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

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:35:45 +00:00
Peter Xu
7a9ddfbfae migration: better error handling with QEMUFile
If the postcopy down due to some reason, we can always see this on dst:

  qemu-system-x86_64: RP: Received invalid message 0x0000 length 0x0000

However in most cases that's not the real issue. The problem is that
qemu_get_be16() has no way to show whether the returned data is valid or
not, and we are _always_ assuming it is valid. That's possibly not wise.

The best approach to solve this would be: refactoring QEMUFile interface
to allow the APIs to return error if there is. However it needs quite a
bit of work and testing. For now, let's explicitly check the validity
first before using the data in all places for qemu_get_*().

This patch tries to fix most of the cases I can see. Only if we are with
this, can we make sure we are processing the valid data, and also can we
make sure we can capture the channel down events correctly.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:34:56 +00:00
Dr. David Alan Gilbert
b9ccaf6d74 migration: Fix early failure cleanup
Avoid crash in cleanup after a very early migration failure
(possibly due to my 688a3dcba9  'Route errors down ...')

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180212160340.15333-2-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2018-02-14 10:31:01 +00:00
Ross Lagerwall
96994fd1e4 migration/xen: Check return value of qemu_fclose
QEMUFile uses buffered IO so when writing small amounts (such as the Xen
device state file), the actual write call and any errors that may occur
only happen as part of qemu_fclose(). Therefore, report IO errors when
saving the device state under Xen by checking the return value of
qemu_fclose().

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Message-Id: <20180206163039.23661-1-ross.lagerwall@citrix.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:18:42 +00:00
Markus Armbruster
452fcdbc49 Include qapi/qmp/qdict.h exactly where needed
This cleanup makes the number of objects depending on qapi/qmp/qdict.h
drop from 4550 (out of 4743) to 368 in my "build everything" tree.
For qapi/qmp/qobject.h, the number drops from 4552 to 390.

While there, separate #include from file comment with a blank line.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-13-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster
15280c360e qdict qlist: Make most helper macros functions
The macro expansions of qdict_put_TYPE() and qlist_append_TYPE() need
qbool.h, qnull.h, qnum.h and qstring.h to compile.  We include qnull.h
and qnum.h in the headers, but not qbool.h and qstring.h.  Works,
because we include those wherever the macros get used.

Open-coding these helpers is of dubious value.  Turn them into
functions and drop the includes from the headers.

This cleanup makes the number of objects depending on qapi/qmp/qnum.h
from 4551 (out of 4743) to 46 in my "build everything" tree.  For
qapi/qmp/qnull.h, the number drops from 4552 to 21.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-10-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster
e688df6bc4 Include qapi/error.h exactly where needed
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.

While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
2018-02-09 13:50:17 +01:00
Markus Armbruster
522ece32d2 Drop superfluous includes of qapi-types.h and test-qapi-types.h
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-4-armbru@redhat.com>
2018-02-09 05:05:11 +01:00
Greg Kurz
875fcd013a migration: incoming postcopy advise sanity checks
If postcopy-ram was set on the source but not on the destination,
migration doesn't occur, the destination prints an error and boots
the guest:

qemu-system-ppc64: Expected vmdescription section, but got 0

We end up with two running instances.

This behaviour was introduced in 2.11 by commit 58110f0acb "migration:
split common postcopy out of ram postcopy" to prepare ground for the
upcoming dirty bitmap postcopy support. It adds a new case where the
source may send an empty postcopy advise because dirty bitmap doesn't
need to check page sizes like RAM postcopy does.

If the source has enabled postcopy-ram, then it sends an advise with
the page size values. If the destination hasn't enabled postcopy-ram,
then loadvm_postcopy_handle_advise() leaves the page size values on
the stream and returns. This confuses qemu_loadvm_state() later on
and causes the destination to start execution.

As discussed several times, postcopy-ram should be enabled both sides
to be functional. This patch changes the destination to perform some
extra checks on the advise length to ensure this is the case. Otherwise
an error is returned and migration is aborted.

Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <151791621042.19120.3103118434734245776.stgit@bahia>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 14:53:02 +00:00
Ross Lagerwall
032b79f717 migration: Don't leak IO channels
Since qemu_fopen_channel_{in,out}put take references on the underlying
IO channels, make sure to release our references to them.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Message-Id: <20171101142526.1006-2-ross.lagerwall@citrix.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 14:53:02 +00:00
Dr. David Alan Gilbert
6039dd5b1c migration: Recover block devices if failure in device state
In e91d895 I added the new pause-before-switchover mechanism
to allow migration completion to be delayed; this changes the
last state prior to completion to MIGRATE_STATUS_DEVICE rather
than MIGRATE_STATUS_ACTIVE.

Fix the failure path in migration_completion to recover the block
devices if it fails in MIGRATE_STATUS_DEVICE, not just the
MIGRATE_STATUS_ACTIVE that it previously had.

This corresponds to rh bz:
  https://bugzilla.redhat.com/show_bug.cgi?id=1538494
whose symptom is an occasional source crash on a failed migration.

Fixes: e91d8951d5
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 14:53:02 +00:00
Juan Quintela
7faccdc3e7 migration: Drop current address parameter from save_zero_page()
It already has RAMBlock and offset, it can calculate it itself.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 10:55:13 +00:00
Wei Wang
0781c1ed1c migration: use s->threshold_size inside migration_update_counters
Fixes: b15df1ae50 ("migration: cleanup stats update into function")
The threshold size is changed to be recorded in s->threshold_size.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Peter Xu <peterx@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>
2018-02-06 10:55:13 +00:00
Daniel Henrique Barboza
ee555cdf4d migration/savevm.c: set MAX_VM_CMD_PACKAGED_SIZE to 1ul << 32
MAX_VM_CMD_PACKAGED_SIZE is a constant used in qemu_savevm_send_packaged
and loadvm_handle_cmd_packaged to determine whether a package is too
big to be sent or received. qemu_savevm_send_packaged is called inside
postcopy_start (migration/migration.c) to send the MigrationState
in a single blob to the destination, using the MIG_CMD_PACKAGED subcommand,
which will read it up using loadvm_handle_cmd_packaged. If the blob is
larger than MAX_VM_CMD_PACKAGED_SIZE, an error is thrown and the postcopy
migration is aborted. Both MAX_VM_CMD_PACKAGED_SIZE and MIG_CMD_PACKAGED
were introduced by commit 11cf1d984b ("MIG_CMD_PACKAGED: Send a packaged
chunk ..."). The constant has its original value of 1ul << 24 (16MB).

The current MAX_VM_CMD_PACKAGED_SIZE value is not enough to support postcopy
migration of bigger pseries guests. The blob size for a postcopy migration of
a pseries guest with the following setup:

qemu-system-ppc64 --nographic -vga none -machine pseries,accel=kvm -m 64G \
-smp 1,maxcpus=32 -device virtio-blk-pci,drive=rootdisk \
-drive file=f27.qcow2,if=none,cache=none,format=qcow2,id=rootdisk \
-netdev user,id=u1 -net nic,netdev=u1

Goes around 12MB. Bumping the RAM to 128G makes the blob sizes goes to 20MB.
With 256G the blob goes to 37MB - more than twice the current maximum size.
At this moment the pseries machine can handle guests with up to 1TB of RAM,
making this postcopy blob goes to 128MB of size approximately.

Following the discussions made in [1], there is a need to understand what
devices are aggressively consuming the blob in that manner and see if that
can be mitigated. Until then, we can set MAX_VM_CMD_PACKAGED_SIZE to the
maximum value allowed. Since the size is a 32 bit int variable, we can set
it as 1ul << 32, giving a maximum blob size of 4G that is enough to support
postcopy migration of 32TB RAM guests given the above constraints.

[1] https://lists.nongnu.org/archive/html/qemu-devel/2018-01/msg06313.html

Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.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>
2018-02-06 10:55:13 +00:00
Dr. David Alan Gilbert
688a3dcba9 migration: Route errors down through migration_channel_connect
Route async errors (especially from sockets) down through
migration_channel_connect and on to migrate_fd_connect where they
can be cleaned up.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@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>
2018-02-06 10:55:12 +00:00