As a rule, CPU internal state should never be updated when
!cpu->kvm_vcpu_dirty (or the HAX equivalent). If that is done, then
subsequent calls to cpu_synchronize_state() - usually safe and idempotent -
will clobber state.
However, we routinely do this during a loadvm or incoming migration.
Usually this is called shortly after a reset, which will clear all the cpu
dirty flags with cpu_synchronize_all_post_reset(). Nothing is expected
to set the dirty flags again before the cpu state is loaded from the
incoming stream.
This means that it isn't safe to call cpu_synchronize_state() from a
post_load handler, which is non-obvious and potentially inconvenient.
We could cpu_synchronize_all_state() before the loadvm, but that would be
overkill since a) we expect the state to already be synchronized from the
reset and b) we expect to completely rewrite the state with a call to
cpu_synchronize_all_post_init() at the end of qemu_loadvm_state().
To clear this up, this patch introduces cpu_synchronize_pre_loadvm() and
associated helpers, which simply marks the cpu state as dirty without
actually changing anything. i.e. it says we want to discard any existing
KVM (or HAX) state and replace it with what we're going to load.
Cc: Juan Quintela <quintela@redhat.com>
Cc: Dave Gilbert <dgilbert@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
We can replace the four remaining calls of register_savevm() by
calls to register_savevm_live(). So we can remove the function and
as we don't allocate anymore the ops pointer with g_new0()
we don't have to free it then.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
All functions were internal, except blk_mig_init() that is exported in
misc.h now.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
All functions are internal except for ram_mig_init(). Create
migration/misc.h for this kind of functions.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Start removing migration code from sysemu/sysemu.h.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Just for the functions exported from tls.c. Notice that we can't
remove the migration/migration.h include from tls.c because it access
directly MigrationState for the tls params.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Split the file into public and internal interfaces. I have to rename
the external one because we can't have two include files with the same
name in the same directory. Build system gets confused. The only
exported functions are the ones that handle basic types.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We were do the shutting off only for postcopy. Now we do this as long as
the source return path is there.
Moving the cleanup of from_src_file there too.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The return path channel is possibly leaked. Fix it.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Everything else assumes that we always load a device from its own
savevm handler.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
So we remove all traces of them.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
There is no reason for having the loadvm_handlers at all. There is
only one use, and we can use the savevm handlers.
We will remove the loadvm handlers on a following patch.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
--
- Added load_version_id: version_id read from the stream (laurent)
- Added load_section_id: section_id read from the stream (dave)
The commit message from 070afca25 suggests that dirty_rate_high_cnt
should be used more aggressively to start throttling after two
iterations instead of four. The code, however, only changes the auto
convergence behaviour to throttle after three iterations. This makes the
behaviour more aggressive by kicking off throttling after two iterations
as originally intended.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The bytes_xfer_now/prev counters are only used by the auto convergence
logic. However, they are used alongside the dirty_pages_rate counter,
which is calculated (and required) outside of this logic. The problem
with this approach is that if the auto convergence capability is changed
while a migration is ongoing, the relationship of the counters will be
broken.
This moves the management of bytes_xfer_now/prev counters outside of the
auto convergence logic to address this issue.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Currently, a "period" in the RAM migration logic is at least a second
long and accounts for what happened since the last period (or the
beginning of the migration). The dirty_pages_rate counter is calculated
at the end this logic.
If the auto convergence capability is enabled from the start of the
migration, it won't be able to use this counter the first time around.
This calculates dirty_pages_rate as soon as a period is deemed over,
which allows for it to be used immediately.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The first time migration_bitmap_sync() is called, bytes_xfer_prev is set
to ram_state.bytes_transferred which is, at this point, zero. The next
time migration_bitmap_sync() is called, an iteration has happened and
bytes_xfer_prev is set to 'x' bytes. Most likely, more than one second
has passed, so the auto converge logic will be triggered and
bytes_xfer_now will also be set to 'x' bytes.
This condition is currently masked by dirty_rate_high_cnt, which will
wait for a few iterations before throttling. It would otherwise always
assume zero bytes have been copied and therefore throttle the guest
(possibly) prematurely.
Given bytes_xfer_prev is only used by the auto convergence logic, it
makes sense to only set its value after a check has been made against
bytes_xfer_now.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This removes last trace of migration functions from sysemu/sysemu.h.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
We want to track why a guest was shutdown; in particular, being able
to tell the difference between a guest request (such as ACPI request)
and host request (such as SIGINT) will prove useful to libvirt.
Since all requests eventually end up changing shutdown_requested in
vl.c, the logical change is to make that value track the reason,
rather than its current 0/1 contents.
Since command-line options control whether a reset request is turned
into a shutdown request instead, the same treatment is given to
reset_requested.
This patch adds an internal enum ShutdownCause that describes reasons
that a shutdown can be requested, and changes qemu_system_reset() to
pass the reason through, although for now nothing is actually changed
with regards to what gets reported. The enum could be exported via
QAPI at a later date, if deemed necessary, but for now, there has not
been a request to expose that much detail to end clients.
For the most part, we turn 0 into SHUTDOWN_CAUSE_NONE, and 1 into
SHUTDOWN_CAUSE_HOST_ERROR; the only specific case where we have enough
information right now to use a different value is when we are reacting
to a host signal. It will take a further patch to edit all call-sites
that can trigger a reset or shutdown request to properly pass in any
other reasons; this patch includes TODOs to point such places out.
qemu_system_reset() trades its 'bool report' parameter for a
'ShutdownCause reason', with all non-zero values having the same
effect; this lets us get rid of the weird #defines for VMRESET_*
as synonyms for bools.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170515214114.15442-3-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
It only needed TARGET_PAGE_SIZE/BITS/BITS_MIN values, so just export
them from exec.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>
That is the only function that we need from exec.c, and having to
include the whole sysemu.h for this.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
/me leans to be less sloppy with copyright notices
thanks Dave
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
Minor rearrangements due to rebase
Now one just has the interperter, and the other has the basic types.
Once there, add copyright boilerplate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Use GPL v2 or later. Detected by David.
Create an include for its exported functions.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
Add proper header
Many users now prefer to use drive_mirror over NBD as an
alternative to the older migrate -b option; drive_mirror is
more complex to setup but gives you more options (e.g. only
migrating some of the disks if some of them are shared).
Allow the large chunk of block migration code to be compiled
out for those who don't use it.
Based on a downstream-patch we've had for a while by Jeff Cody.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
--
- When compiled out, allow seting block only with false value (eric)
Not used anymore after moving block migration to use capabilities.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
We have change in the previous patch to use migration capabilities for
it. Notice that we continue using the old command line flags from
migrate command from the time being. Remove the set_params method as
now it is empty.
For savevm, one can't do a:
savevm -b/-i foo
but now one can do:
migrate_set_capability block on
savevm foo
And we can't use block migration. We could disable block capability
unconditionally, but it would not be much better.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
- Maintain shared/enabled dependency (Xu suggestion)
- Now we maintain the dependency on the setter functions
- improve error messages
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
It turns out that it's legal to create a VM with RAMBlocks that aren't
a multiple of the pagesize in use; e.g. a 1025M main memory using
2M host pages. That breaks postcopy's atomic placement of pages,
so disallow 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>
Unfortunately it's legal to create a VM with a RAM size that's
not a multiple of the underlying host page or huge page size.
Recently I'd changed things to always send host sized pages,
and that breaks if we have say a 1025MB guest on 2MB hugepages.
Unfortunately we can't just make that illegal since it would break
migration from/to existing oddly configured VMs.
Symptom: qemu-system-x86_64: Illegal RAM offset 40100000
as it transmits the fraction of the hugepage after the end
of the RAMBlock (may also cause a crash on the source
- possibly due to clearing bits after the bitmap)
Reported-by: Yumei Huang <yuhuang@redhat.com>
Red Hat bug: https://bugzilla.redhat.com/show_bug.cgi?id=1449037
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>
-----BEGIN PGP SIGNATURE-----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=wJvl
-----END PGP SIGNATURE-----
Merge remote-tracking branch 'dgilbert/tags/pull-hmp-20170517' into staging
HMP pull
# gpg: Signature made Wed 17 May 2017 07:03:39 PM BST
# gpg: using RSA key 0x0516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.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: 45F5 C71B 4A0C B7FB 977A 9FA9 0516 331E BC5B FDE7
* dgilbert/tags/pull-hmp-20170517:
ramblock: add new hmp command "info ramblock"
utils: provide size_to_str()
ramblock: add RAMBLOCK_FOREACH()
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
So that it can simplifies the iterators.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1494562661-9063-2-git-send-email-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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>
Reflects better what it does now, and avoid confussions with
RAM_SAVE_FLAG_COMPRESS_PAGE.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
This way we use the "normal" way of printing errors for hmp commands.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Compression threads got broken on commit
commit 2479569466
Author: Juan Quintela <quintela@redhat.com>
Date: Tue Mar 21 11:45:01 2017 +0100
ram: reorganize last_sent_block
On do_compress_ram_page() we use a different QEMUFile than the
migration one. We need to pass it there. The failure can be seen as:
(qemu) qemu-system-x86_64: Unknown combination of migration flags: 0
qemu-system-x86_64: error while loading state section id 3(ram)
qemu-system-x86_64: load of migration failed: Invalid argument
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Instead of manually calling blk_resume_after_migration() in migration
code after doing bdrv_invalidate_cache_all(), integrate the BlockBackend
activation with cache invalidation into a single function. This is
achieved with a new callback in BdrvChildRole that is called by
bdrv_invalidate_cache_all().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Migration code activates all block driver nodes on the destination when
the migration completes. It does so by calling
bdrv_invalidate_cache_all() and blk_resume_after_migration(). There is
one code path for precopy and one for postcopy migration, resulting in
four function calls, which used to have three different failure modes.
This patch unifies the behaviour so that failure to activate all block
nodes is non-fatal, but the error message is logged and the VM isn't
automatically started. 'cont' will retry activating the block nodes.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
