Create one capability for block migration and one parameter for
incremental block migration.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
- address all Markus comments
- use Markus and Eric text descriptions
- change logic another time
- improve text messages
The function is only used once, and nothing else in migration knows
about objects. Create the function vmstate_device_is_migratable() in
savem.c that really do the bit that is related with migration.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Yes, we don't have a good place to put that stuff.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
It is only used by migration, so move it there.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This allows us to remove lots of includes of migration/migration.h
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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Merge remote-tracking branch 'shorne/tags/pull-or-20170504' into staging
Openrisc Features and Fixes for qemu 2.10
# gpg: Signature made Thu 04 May 2017 01:41:45 AM BST
# gpg: using RSA key 0xC3B31C2D5E6627E4
# gpg: Good signature from "Stafford Horne <shorne@gmail.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: D9C4 7354 AEF8 6C10 3A25 EFF1 C3B3 1C2D 5E66 27E4
* shorne/tags/pull-or-20170504:
target/openrisc: Support non-busy idle state using PMR SPR
target/openrisc: Remove duplicate features property
target/openrisc: Implement full vmstate serialization
migration: Add VMSTATE_STRUCT_2DARRAY()
target/openrisc: implement shadow registers
migration: Add VMSTATE_UINTTL_2DARRAY()
target/openrisc: add numcores and coreid support
target/openrisc: Fixes for memory debugging
target/openrisc: Implement EPH bit
target/openrisc: Implement EVBAR register
MAINTAINERS: Add myself as openrisc maintainer
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It is internal to migration, not intended for other users.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Both the ram bitmap and the unsent bitmap are split by RAMBlock.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Fix compilation when DEBUG_POSTCOPY is enabled (thanks Hailiang)
For openrisc we implement tlb state as a 2d array of tlb entry structs.
This is added to allow easy storing of state of 2d arrays.
Signed-off-by: Stafford Horne <shorne@gmail.com>
In openRISC we are implementing the shadow registers as a 2d array.
Using this target long method rather than direct 32-bit alternatives is
consistent with the rest of our vm state serialization logic.
Signed-off-by: Stafford Horne <shorne@gmail.com>
In migration codes (especially in migration_thread()), max_size is used
in many place for the threshold value that we will start to do the final
flush and jump to the next stage to dump the whole rest things to
destination. However its name is confusing to first readers. Let's
rename it to "threshold_size" when proper and add a comment for it. No
functional change is made.
CC: Juan Quintela <quintela@redhat.com>
CC: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Only user don't have a MigrationState handly.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We need to call for the migrate_get_current() in more that half of the
uses, so call that inside.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Treat it like the rest of ram stats counters. Export its value the
same way. As an added bonus, no more MigrationState used in
migration_bitmap_sync();
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Again, dave was the one reviewing it
It can be recalculated from dirty_pages_rate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Dave was the one that reviewed it O:-)
This is a ram field that was inside MigrationState. Move it to
RAMState and make it the same that the other ram stats.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
This are the last postcopy fields still at MigrationState. Once there
Move MigrationSrcPageRequest to ram.c and remove MigrationState
parameters where appropiate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
It was on MigrationState when it is only used inside ram.c for
postcopy. Problem is that we need to access it without being able to
pass it RAMState directly.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Its value can be calculated by other exported.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
For compatibility, we need to still send a value, but just specify it
and comment the fact.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
It reflects better what it does.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
The kernel can't do UFFDIO_ZEROPAGE for huge pages, so we have
to allocate a temporary (always zero) page and use UFFDIO_COPYPAGE
on it.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-9-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Now we deal with normal size pages and huge pages we need
to tell the place handlers the size we're dealing with
and make sure the temporary page is large enough.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-8-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Record the largest page size in use; we'll need it soon for allocating
temporary buffers.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-7-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Create ram_block_discard_range in exec.c to replace
postcopy_ram_discard_range and most of ram_discard_range.
Those two routines are a bit of a weird combination, and
ram_discard_range is about to get more complex for hugepages.
It's OS dependent code (so shouldn't be in migration/ram.c) but
it needs quite a bit of the innards of RAMBlock so doesn't belong in
the os*.c.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-5-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Replace the host page-size in the 'advise' command by a pagesize
summary bitmap; if the VM is just using normal RAM then
this will be exactly the same as before, however if they're using
huge pages they'll be different, and thus:
a) Migration from/to old qemu's that don't understand huge pages
will fail early.
b) Migrations with different size RAMBlocks will also fail early.
This catches it very early; earlier than the detailed per-block
check in the next patch.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20170224182844.32452-2-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Commit a3a3d8c7 introduced a segfault bug while checking for
'dc->vmsd->unmigratable' which caused QEMU to crash when trying to add
devices which do no set their 'dc->vmsd' yet while initialization.
Place a 'dc->vmsd' check prior to it so that we do not segfault for
such devices.
NOTE: This doesn't compromise the functioning of --only-migratable
option as all the unmigratable devices do set their 'dc->vmsd'.
Introduce a new function check_migratable() and move the
only_migratable check inside it, also use stubs to avoid user-mode qemu
build failures.
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1487009088-23891-1-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Make VMS_ARRAY_OF_POINTER cope with null pointers. Previously the
reward for trying to migrate an array with some null pointers in it was
an illegal memory access, that is a swift and painless death of the
process. Let's make vmstate cope with this scenario.
The general approach is, when we encounter a null pointer (element),
instead of following the pointer to save/load the data behind it, we
save/load a placeholder. This way we can detect if we expected a null
pointer at the load side but not null data was saved instead.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170222160119.52771-4-pasic@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
VMSTATE_WITH_TMP is for handling structures where some calculation
or rearrangement of the data needs to be performed before the data
hits the wire.
For example, where the value on the wire is an offset from a
non-migrated base, but the data in the structure is the actual pointer.
To use it, a temporary type is created and a vmsd used on that type.
The first element of the type must be 'parent' a pointer back to the
type of the main structure. VMSTATE_WITH_TMP takes care of allocating
and freeing the temporary before running the child vmsd.
The post_load/pre_save on the child vmsd can copy things from the parent
to the temporary using the parent pointer and do any other calculations
needed; it can then use normal VMSD entries to do the actual data
storage without having to fiddle around with qemu_get_*/qemu_put_*
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>
Message-Id: <20170203160651.19917-3-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
VMSTATE_UNUSED_VARRAY_UINT32 is used to skip a chunk of the stream
that's an n-element array; note the array size and the dynamic value
read never get multiplied so there's no overflow risk.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170203160651.19917-2-dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
If the net connection between primary host and secondary host breaks
while COLO/COLO incoming threads are doing read() or write().
It will block until connection is timeout, and the failover process
will be blocked because of it.
So it is necessary to shutdown all the socket fds used by COLO
to avoid this situation. Besides, we should close the corresponding
file descriptors after failvoer BH shutdown them,
Or there will be an error.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1484657864-21708-3-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
If we set checkpoint-delay through command 'migrate-set-parameters',
It will not take effect until we finish last sleep chekpoint-delay,
That's will be offensive espeically when we want to change its value
from an extreme big one to a proper value.
Fix it by using timer to realize checkpoint-delay.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-Id: <1484657864-21708-2-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The member VMStateField.start is used for two things, partial data
migration for VBUFFER data (basically provide migration for a
sub-buffer) and for locating next in QTAILQ.
The implementation of the VBUFFER feature is broken when VMSTATE_ALLOC
is used. This however goes unnoticed because actually partial migration
for VBUFFER is not used at all.
Let's consolidate the usage of VMStateField.start by removing support
for partial migration for VBUFFER.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Message-Id: <20170203175217.45562-1-pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
After the start of postcopy migration there are some non-dirty pages which have
already been migrated. These pages are no longer needed on the source vm so that
we can free them and it doen't hurt to complete the migration.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Message-Id: <20170203152321.19739-4-pbutsykin@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This feature frees the migrated memory on the source during postcopy-ram
migration. In the second step of postcopy-ram migration when the source vm
is put on pause we can free unnecessary memory. It will allow, in particular,
to start relaxing the memory stress on the source host in a load-balancing
scenario.
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Message-Id: <20170203152321.19739-3-pbutsykin@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Manually merged in Pavel's 'migration: madvise error_report fixup!'
The qdev id of a device can be huge if it's on the end of a chain
of bridges; in reality such chains shouldn't occur but they can
be made to by chaining PCIe bridges together.
The migration format has a number of 256 character long format
limits; check we don't hit them (we already use pstrcat/cpy but
that just protects us from buffer overruns, we fairly quickly
hit an assert).
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20170202125956.21942-3-dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
I'll be adding an error to it in a subsequent patch.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20170202125956.21942-2-dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1485207141-1941-3-git-send-email-quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
commit fe904ea824 fixed a case
which migration aborted QEMU because it didn't regain the control
of images while some errors happened.
Actually, there are another two cases can trigger the same error reports:
" bdrv_co_do_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed",
Case 1, codes path:
migration_thread()
migration_completion()
bdrv_inactivate_all() ----------------> inactivate images
qemu_savevm_state_complete_precopy()
socket_writev_buffer() --------> error because destination fails
qemu_fflush() ----------------> set error on migration stream
-> qmp_migrate_cancel() ----------------> user cancelled migration concurrently
-> migrate_set_state() ------------------> set migrate CANCELLIN
migration_completion() -----------------> go on to fail_invalidate
if (s->state == MIGRATION_STATUS_ACTIVE) -> Jump this branch
Case 2, codes path:
migration_thread()
migration_completion()
bdrv_inactivate_all() ----------------> inactivate images
migreation_completion() finished
-> qmp_migrate_cancel() ---------------> user cancelled migration concurrently
qemu_mutex_lock_iothread();
qemu_bh_schedule (s->cleanup_bh);
As we can see from above, qmp_migrate_cancel can slip in whenever
migration_thread does not hold the global lock. If this happens after
bdrv_inactive_all() been called, the above error reports will appear.
To prevent this, we can call bdrv_invalidate_cache_all() in qmp_migrate_cancel()
directly if we find images become inactive.
Besides, bdrv_invalidate_cache_all() in migration_completion() doesn't have the
protection of big lock, fix it by add the missing qemu_mutex_lock_iothread();
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-Id: <1485244792-11248-1-git-send-email-zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
migrate_add_blocker should rightly fail if the '--only-migratable'
option was specified and the device in use should not be able to
perform the action which results in an unmigratable VM.
Make migrate_add_blocker return -EACCES in this case.
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-6-git-send-email-ashijeetacharya@gmail.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>
If a migration is already in progress and somebody attempts
to add a migration blocker, this should rightly fail.
Add an errp parameter and a retcode return value to migrate_add_blocker.
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-5-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Merged with recent 'Allow invtsc migration' change
Add a new option "--only-migratable" in qemu which will allow to add
only those devices which will not fail qemu after migration. Devices
set with the flag 'unmigratable' cannot be added when this option will
be used.
Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1484566314-3987-3-git-send-email-ashijeetacharya@gmail.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>
Currently we cannot directly transfer a QTAILQ instance because of the
limitation in the migration code. Here we introduce an approach to
transfer such structures. We created VMStateInfo vmstate_info_qtailq
for QTAILQ. Similar VMStateInfo can be created for other data structures
such as list.
When a QTAILQ is migrated from source to target, it is appended to the
corresponding QTAILQ structure, which is assumed to have been properly
initialized.
This approach will be used to transfer pending_events and ccs_list in spapr
state.
We also create some macros in qemu/queue.h to access a QTAILQ using pointer
arithmetic. This ensures that we do not depend on the implementation
details about QTAILQ in the migration code.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-3-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Current migration code cannot handle some data structures such as
QTAILQ in qemu/queue.h. Here we extend the signatures of put/get
in VMStateInfo so that customized handling is supported. put now
will return int type.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jianjun Duan <duanj@linux.vnet.ibm.com>
Message-Id: <1484852453-12728-2-git-send-email-duanj@linux.vnet.ibm.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
IOMMU needs to be migrated before all the PCI devices (in case there are
devices that will request for address translation). So marking it with a
priority higher than the default (which PCI devices and other belong).
Migration framework handled the rest.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
During migration, save state entries are saved/loaded without a specific
order - we just traverse the savevm_state.handlers list and do it one by
one. This might not be enough.
There are requirements that we need to load specific device's vmstate
first before others. For example, VT-d IOMMU contains DMA address
remapping information, which is required by all the PCI devices to do
address translations. We need to make sure IOMMU's device state is
loaded before the rest of the PCI devices, so that DMA address
translation can work properly.
This patch provide a VMStateDescription.priority value to allow specify
the priority of the saved states. The loadvm operation will be done with
those devices with higher vmsd priority.
Before this patch, we are possibly achieving the ordering requirement by
an assumption that the ordering will be the same with the ordering that
objects are created. A better way is to mark it out explicitly in the
VMStateDescription table, like what this patch does.
Current ordering logic is still naive and slow, but after all that's not
a critical path so IMO it's a workable solution for now.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>