Currently creating a QEMUFile instance from a QIOChannel is
quite simple only requiring a single call to
qemu_fopen_channel_input or qemu_fopen_channel_output
depending on the end of migration connection.
When QEMU gains TLS support, however, there will need to be
a TLS negotiation done inbetween creation of the QIOChannel
and creation of the final QEMUFile. Introduce some helper
methods that will encapsulate this logic, isolating the
migration protocol drivers from knowledge about TLS.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-10-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Instead of relying on the default QEMUFile I/O blocking flag
state, explicitly turn on blocking I/O for outgoing migration
since it takes place in a background thread.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-8-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Remove the assumption that every QEMUFile implementation has
a file descriptor available by introducing a new function
in QEMUFileOps to change the blocking state of a QEMUFile.
If not set, it will fallback to the original code using
the get_fd method.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-7-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
We currently have an error path during migration that can cause
the source QEMU to abort:
migration_thread()
migration_completion()
runstate_is_running() ----------------> true if guest is running
bdrv_inactivate_all() ----------------> inactivate images
qemu_savevm_state_complete_precopy()
... qemu_fflush()
socket_writev_buffer() --------> error because destination fails
qemu_fflush() -------------------> set error on migration stream
migration_completion() -----------------> set migrate state to FAILED
migration_thread() -----------------------> break migration loop
vm_start() -----------------------------> restart guest with inactive
images
and you get:
qemu-system-ppc64: socket_writev_buffer: Got err=104 for (32768/18446744073709551615)
qemu-system-ppc64: /home/greg/Work/qemu/qemu-master/block/io.c:1342:bdrv_co_do_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
Aborted (core dumped)
If we try postcopy with a similar scenario, we also get the writev error
message but QEMU leaves the guest paused because entered_postcopy is true.
We could possibly do the same with precopy and leave the guest paused.
But since the historical default for migration errors is to restart the
source, this patch adds a call to bdrv_invalidate_cache_all() instead.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Message-Id: <146357896785.6003.11983081732454362715.stgit@bahia.huguette.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
QEMU has currently two ways to prevent migration to occur:
- migration blocker when it depends on runtime state
- VMStateDescription.unmigratable when migration is not supported at all
This patch gathers all the logic into a single function to be called from
both the savevm and the migrate paths.
This fixes a bug with 9p, at least, where savevm would succeed and the
following would happen in the guest after loadvm:
$ ls /host
ls: cannot access /host: Protocol error
With this patch:
(qemu) savevm foo
Migration is disabled when VirtFS export path '/' is mounted in the guest
using mount_tag 'host'
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <146239057139.11271.9011797645454781543.stgit@bahia.huguette.org>
[Update subject according to Paolo's suggestion - Amit]
Signed-off-by: Amit Shah <amit.shah@redhat.com>
The new autoconverge throttling commands have been tested for a release now. It
is time to move them out of the experimental state.
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Message-Id: <1461262038-8197-1-git-send-email-jjherne@linux.vnet.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)
Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Postcopy seems to have survived a cycle with only a few fixes,
and Jiri has the current libvirt wired up and working
( https://www.redhat.com/archives/libvir-list/2016-March/msg00080.html )
so remove the experimental tag.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457690016-9070-3-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
max_len is not necessary, while it brings a warning during compilation
when specify "-Wstack-usage=1000000". Replacing using sizeof().
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1457503932-31763-1-git-send-email-peterx@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
I'd missed the sync count off in the postcopy case.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-id: 1456394631-18010-1-git-send-email-dgilbert@redhat.com
Message-Id: <1456394631-18010-1-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
There is a possibility to hit an assert in qcow2_get_specific_info that
s->qcow_version is undefined. This happens when VM in starting from
suspended state, i.e. it processes incoming migration, and in the same
time 'info block' is called.
The problem is that qcow2_invalidate_cache() closes the image and
memset()s BDRVQcowState in the middle.
The patch moves processing of bdrv_invalidate_cache_all out of
coroutine context for standard migration to avoid that.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>
Message-Id: <1456304019-10507-2-git-send-email-den@openvz.org>
[Amit: Fix a use-after-free bug]
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Spice hooks the migration status changes to figure out when to
transmit information to the new spice server; but the migration
status in postcopy doesn't quite fit - the destination starts
running before the end of the source migration.
It's not a case of hanging off the migration status change to
postcopy-active either, since that happens before we stop the
guest CPU.
Fix it by sending a notify just after sending the device state,
and adding a flag that can be tested by the notify receiver.
Symptom:
spice handover doesn't work with the error:
red_worker.c:11540:display_channel_wait_for_migrate_data: timeout
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-id: 1456161452-25318-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Within the if statement, time_spent is assured to be non-zero.
This patch just removes the check on time_spent when calculating mbs.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Since 's->state' will be set in migrate_init(), there is no
need to set it before calling migrate_init(). The code and
the related comments can be removed.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1453875065-24326-1-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Rename the 'file' member of MigrationState to 'to_dst_file' to
be consistent with to_src_file, from_src_file and from_dst_file.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1452829066-9764-3-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-2-git-send-email-peter.maydell@linaro.org
So far, live migration with shared storage meant that the image is in a
not-really-ready don't-touch-me state on the destination while the
source is still actively using it, but after completing the migration,
the image was fully opened on both sides. This is bad.
This patch adds a block driver callback to inactivate images on the
source before completing the migration. Inactivation means that it goes
to a state as if it was just live migrated to the qemu instance on the
source (i.e. BDRV_O_INACTIVE is set). You're then supposed to continue
either on the source or on the destination, which takes ownership of the
image.
A typical migration looks like this now with respect to disk images:
1. Destination qemu is started, the image is opened with
BDRV_O_INACTIVE. The image is fully opened on the source.
2. Migration is about to complete. The source flushes the image and
inactivates it. Now both sides have the image opened with
BDRV_O_INACTIVE and are expecting the other side to still modify it.
3. One side (the destination on success) continues and calls
bdrv_invalidate_all() in order to take ownership of the image again.
This removes BDRV_O_INACTIVE on the resuming side; the flag remains
set on the other side.
This ensures that the same image isn't written to by both instances
(unless both are resumed, but then you get what you deserve). This is
important because .bdrv_close for non-BDRV_O_INACTIVE images could write
to the image file, which is definitely forbidden while another host is
using the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
For migration destination, we also need to know its state,
we will use it in COLO.
Here we add a new member 'state' for MigrationIncomingState,
and also use migrate_set_state() to modify its value.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
dgilbert: Fixed early free of MigraitonIncomingState
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1450266458-3178-3-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Change the first parameter of migrate_set_state(), and export it.
We will use it in a later patch to update incoming state.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert: Updated comment as per Juan's review
Message-Id: <1450266458-3178-2-git-send-email-dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes. Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.
This patch was mostly generated by applying a temporary patch:
|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
| max_index = c_enum_const(name, 'MAX', prefix)
| ret += mcgen('''
| [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
| max_index=max_index)
then running:
$ cat qapi-{types,event}.c tests/test-qapi-types.c |
sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list
The only things not generated are the changes in scripts/qapi.py.
Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Dividing integer expressions transferred_bytes and time_spent, and then converting
the integer quotient to type double. Any remainder, or fractional part of the
quotient, is ignored. Fix this.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The check is unneccesary, we read the value at the start of the
thread, use it, and never change it. The value is checked to be
non-NULL before thread creation.
Spotted by coverity, CID 1339211
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
I set current_time before the postcopy test but never use it;
(I think this was from the original version where it was time based).
Spotted by coverity, CID 1339208
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Peter reported a lock error on MacOS after my a82d593b
patch.
migrate_get_current does one-time initialisation of
a bunch of variables.
migrate_init does reinitialisation even on a 2nd
migrate after a cancel.
The problem here was that I'd initialised the mutex
in migrate_get_current, and the memset in migrate_init
corrupted it.
Remove the memset and replace it by explicit initialisation
of fields that need initialising; this also turns out to be simpler
than the old code that had to preserve some fields.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: a82d593b
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Improve the text in both the qapi-schema and hmp help to point out
you need to set the postcopy-ram capability prior to issuing
migrate-start-postcopy.
Also fix the text of the migrate_start_postcopy error that
deals with capabilities.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Where we have iterable, but non-postcopiable devices (e.g. htab
or block migration), complete them before forming the 'package'
but with the CPUs stopped. This stops them filling up the package.
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>
Tweak the end of migration cleanup; we don't want to close stuff down
at the end of the main stream, since the postcopy is still sending pages
on the other thread.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The loading of a device state (during postcopy) may access guest
memory that's still on the source machine and thus might need
a page fill; split off a separate thread that handles the incoming
page data so that the original incoming migration code can finish
off the device data.
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>
During the postcopy phase we must not call the iterate method on
precopy-only devices, since they may have done some cleanup during
the _complete call at the end of the precopy phase.
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>
On receiving MIG_RPCOMM_REQ_PAGES look up the address and
queue the page.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Add MIG_RP_MSG_REQ_PAGES command on Return path for the postcopy
destination to request a page from the source.
Two versions exist:
MIG_RP_MSG_REQ_PAGES_ID that includes a RAMBlock name and start/len
MIG_RP_MSG_REQ_PAGES that just has start/len for use with the same
RAMBlock as a previous MIG_RP_MSG_REQ_PAGES_ID
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The end of migration in postcopy is a bit different since some of
the things normally done at the end of migration have already been
done on the transition to postcopy.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Rework the migration thread to setup and start postcopy.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Soon we'll be in either ACTIVE or POSTCOPY_ACTIVE when we
complete migration, and we need to know which we expect to be
in to change state safely.
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>
'MIGRATION_STATUS_POSTCOPY_ACTIVE' is entered after migrate_start_postcopy
'migration_in_postcopy' is provided for other sections to know if
they're in postcopy.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Soon we'll be in either ACTIVE or POSTCOPY_ACTIVE when we
complete migration, and we need to know which we expect to be
in to change state safely.
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>
Once postcopy is enabled (with migrate_set_capability), the migration
will still start on precopy mode. To cause a transition into postcopy
the:
migrate_start_postcopy
command must be issued. Postcopy will start sometime after this
(when it's next checked in the migration loop).
Issuing the command before migration has started will error,
and issuing after it has finished is ignored.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Modify save_live_pending to return separate postcopiable and
non-postcopiable counts.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The state of the postcopy process is managed via a series of messages;
* Add wrappers and handlers for sending/receiving these messages
* Add state variable that track the current state of postcopy
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The 'postcopy ram' capability allows postcopy migration of RAM;
note that the migration starts off in precopy mode until
postcopy mode is triggered (see the migrate_start_postcopy
patch later in the series).
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Postcopy needs to have two migration streams loading concurrently;
one from memory (with the device state) and the other from the fd
with the memory transactions.
Split the core of qemu_loadvm_state out so we can use it for both.
Allow the inner loadvm loop to quit and cause the parent loops to
exit as well.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Open a return path, and handle messages that are received upon it.
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>
Add 'migration_is_setup_or_active' utility function to check state.
(It gets postcopy added to it's list later on in the series)
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>
Add migrate_send_rp_message to send a message from destination to source along the return path.
(It uses a mutex to let it be called from multiple threads)
Add migrate_send_rp_shut to send a 'shut' message to indicate
the destination is finished with the RP.
Add migrate_send_rp_ack to send a 'PONG' message in response to a PING
Use it in the MSG_RP_PING handler
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
In postcopy we're going to need to perform the complete phase
for postcopiable devices at a different point, start out by
renaming all of the 'complete's to make the difference obvious.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Suspend to file is very much like a migrate, and it makes life
easier if we have the Migration state available, so initialise it
in the savevm.c code for suspending.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewd-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
'file' becomes confusing when you have flows in each direction;
rename to make it clear.
This leaves just the main forward direction ms->file, which is used
in a lot of places and is probably not worth renaming given the churn.
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>
The function qemu_savevm_state_cancel is called after the migration
in migration_thread, it seems strange to 'cancel' it after completion,
rename it to qemu_savevm_state_cleanup looks better.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>al3
Reviewed-by: Amit Shah <amit.shah@redhat.com>al3
Signed-off-by: Juan Quintela <quintela@redhat.com>al3
Because of the patch 3ea3b7fa9af067982f34b of kvm, which introduces a
lazy collapsing of small sptes into large sptes mechanism, now
migration_end() is a time consuming operation because it calls
memroy_global_dirty_log_stop(), which will trigger the dropping of small
sptes operation and takes about dozens of milliseconds, so call
migration_end() before all the vmsate data has already been transferred
to the destination will prolong VM downtime. This operation should be
deferred after all the data has been transferred to the destination.
blk_mig_cleanup() can be deferred too.
For a VM with 8G RAM, this patch can reduce the VM downtime about 30 ms.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>al3
Reviewed-by: Amit Shah <amit.shah@redhat.com>al3
Signed-off-by: Juan Quintela <quintela@redhat.com>al3