The migrate command is one of those commands where HMP and QMP completely
mix up together. This made the conversion to the QAPI (which separates the
command into QMP and HMP parts) a bit difficult.
The first important change to be noticed is that this commit completes the
removal of the Monitor object from migration code, started by the previous
commit.
Another important and tricky change is about supporting the non-detached
mode. That is, if the user doesn't pass '-d' the migrate command will lock
the monitor and will only release it when migration is finished.
To support this in the new HMP command (hmp_migrate()), it is necessary
to create a timer which runs every second and checks if the migration is
still active. If it is, the timer callback will re-schedule itself to run
one second in the future. If the migration has already finished, the
monitor lock is released and the user can use it normally.
All these changes should be transparent to the user.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The Monitor object is passed back and forth within the migration/savevm
code so that it can print errors and progress to the user.
However, that approach assumes a HMP monitor, being completely invalid
in QMP.
This commit drops almost every single usage of the Monitor object, all
monitor_printf() calls have been converted into DPRINTF() ones.
There are a few remaining Monitor objects, those are going to be dropped
by the next commit.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The variable is deleted by 1bcef683bf
So remove its declaration.
Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
This lets different subsystems register an Error that is thrown whenever
migration is attempted. This works nicely because it gracefully supports
things like hotplug.
Right now, if multiple errors are registered, only one of them is reported.
I expect that for 1.1, we'll extend query-migrate to return all of the reasons
why migration is disabled at any given point in time.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
It is only used inside migration.c, and fields on that struct are
accessed all around the place on that file.
Signed-off-by: Juan Quintela <quintela@redhat.com>
We called it from a single place, and always with state !=
MIG_STATE_ACTIVE. Just remove the whole callback. For users of the
notifier, notice that this is exactly the case where they don't care,
we are just freeing the state from previous failed migration (it can't
be a sucessful one, otherwise we would not be running on that machine
in the first place).
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Use MIG_STATE_ACTIVE only when migration has really started. Use this
new state to setup migration parameters. Change defines for an
anonymous struct.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Once there, remove all parameters that don't need to be passed to
*start_outgoing_migration() functions
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
I have to move two functions postions to avoid forward declarations
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
This patch adds functions to register and unregister notifiers for
migration state changes and a function to query the migration state.
The notifier is called on every state change. Once after establishing a
new migration object (which is in active state then) and once when the
state changes from active to completed, canceled or error.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch makes sure that if the exec: process exits with a non-zero return
status, we treat the migration as failed.
This fixes https://bugs.launchpad.net/qemu/+bug/391879
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
While there I'm also dropping a unneeded else clause (the last
one in the function).
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The following handlers always succeed and hence can be converted
to cmd_new_ret() in the same commit.
- do_stop()
- do_quit()
- do_system_reset()
- do_system_powerdown()
- do_migrate_cancel()
- do_qmp_capabilities()
- do_migrate_set_speed()
- do_migrate_set_downtime()
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This reverts commit 3a4921047d.
From Luiz:
do_migrate_set_speed() accepts a suffix for the 'value' argument and this is
not good for QMP. We will have to add a new argument type to handle that and
this will have to wait for 0.13.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Return a QDict, which may contain up to more two QDicts, depending
on the type of migration we're performing.
IMPORTANT: as a QInt stores a int64_t integer, RAM values are going
to be stored as int64_t and not as uint64_t as they are today. If
this is a problem QInt will have to be changed.
This commit should not change user output.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In order to allow proper progress reporting to the monitor that
initiated the migration, forward the monitor reference through the
migration layer down to SaveLiveStateHandler.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch introduces block migration called during live migration. Block
are being copied to the destination in an async way. First the code will
transfer the whole disk and then transfer all dirty blocks accumulted during
the migration.
Still need to improve transition from the iterative phase of migration to the
end phase. For now transition will take place when all blocks transfered once,
all the dirty blocks will be transfered during the end phase (guest is
suspended).
Changes from v4:
- Global variabels moved to a global state structure allocated dynamically.
- Minor coding style issues.
- Poll block.c for tracking of dirty blocks instead of manage it here.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Error is still directly printed, as we are only converting
regular output.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit ports command handlers that receive two arguments to use
the new monitor's dictionary.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit ports command handlers that receive one argument to use
the new monitor's dictionary.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit ports command handlers that receive no arguments to use
the new monitor's dictionary.
It might seem no sense to do this, as the handlers have no arguments,
but at the end of this porting work all handlers will have the same
structure.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Implement migration via unix sockets. While you can fake this using
exec and netcat, this involves forking another process and is
generally not very nice. By doing this directly in qemu, we can avoid
the copy through the external nc command. This is useful for
implementations (such as libvirt) that want to do "secure" migration;
we pipe the data on the sending side into the unix socket, libvirt
picks it up, encrypts it, and transports it, and then on the remote
side libvirt decrypts it, dumps it to another unix socket, and
feeds it into qemu.
The implementation is straightforward and looks very similar to
migration-exec.c and migration-tcp.c
Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
provide a monitor command to allow one to set the maximum
downtime he is willing to suffer during migration, in seconds.
"ms", "us", "ns" and "s" are accepted as modifiers.
This parameter will be used by ram_save_live() code to determine
a safe moment to enter stage 3
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Currently, we're entering migration's stage 3 when
a treshold of 10 pages remain to be transferred in the system.
This has hurt some users. However, any proposed threshold is
arbitrary by nature, and would only shift the annoyance.
The proposal of this patch is to define a max_downtime variable,
which represents the maximum downtime a migration user is willing
to suffer. Then, based on the bandwidth of last iteration, we
calculate how much data we can transfer in such a window of time.
Whenever we reach that value (or lower), we know is safe to enter
stage3.
This has largely improved the situation for me.
On localhost migrations, where one would expect things to go as
quickly as me running away from the duty of writting software for
windows, a kernel compile was enough to get the migration stuck.
It takes 20 ~ 30 iterations now.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Currently all registered (and activate) monitor terminals work in
broadcast mode: Everyone sees what someone else types on some other
terminal and what the monitor reports back. This model is broken when
you have a management monitor terminal that is automatically operated
and some other terminal used for independent guest inspection. Such
additional terminals can be multiplexed device channels or a gdb
frontend connected to QEMU's stub.
Therefore, this patch decouples the buffers and states of all monitor
terminals, allowing the user to operate them independently. It finally
starts to use the 'mon' parameter that was introduced earlier with the
API rework. It also defines the default monitor: the first instantance
that has the MONITOR_IS_DEFAULT flag set, and that is the monitor
created via the "-monitor" command line switch (or "vc" if none is
given).
As the patch requires to rework the monitor suspension interface, it
also takes the freedom to make it "truely" suspending (so far suspending
meant suppressing the prompt, but inputs were still processed).
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6715 c046a42c-6fe2-441c-8c8c-71466251a162
Refactor the monitor API and prepare it for decoupled terminals:
term_print functions are renamed to monitor_* and all monitor services
gain a new parameter (mon) that will once refer to the monitor instance
the output is supposed to appear on. However, the argument remains
unused for now. All monitor command callbacks are also extended by a mon
parameter so that command handlers are able to pass an appropriate
reference to monitor output services.
For the case that monitor outputs so far happen without clearly
identifiable context, the global variable cur_mon is introduced that
shall once provide a pointer either to the current active monitor (while
processing commands) or to the default one. On the mid or long term,
those use case will be obsoleted so that this variable can be removed
again.
Due to the broad usage of the monitor interface, this patch mostly deals
with converting users of the monitor API. A few of them are already
extended to pass 'mon' from the command handler further down to internal
functions that invoke monitor_printf.
At this chance, monitor-related prototypes are moved from console.h to
a new monitor.h. The same is done for the readline API.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6711 c046a42c-6fe2-441c-8c8c-71466251a162
KVM's live migration support included support for exec: URLs, allowing system
state to be written or received via an arbitrary popen()ed subprocess. This
provides a convenient way to pipe state through a compression algorithm or an
arbitrary network transport on its way to its destination, and a convenient way
to write state to disk; libvirt's qemu driver currently uses migration to exec:
targets for this latter purpose.
This version of the patch refactors now-common code from migrate-tcp.c into
migrate.c.
Signed-off-by: Charles Duffy <Charles_Duffy@messageone.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5694 c046a42c-6fe2-441c-8c8c-71466251a162
This patch introduces a tcp protocol for live migration. It can be used as
follows:
qemu-system-x86_64 -hda ~/images/linux-test.img -monitor stdio
<vm runs for a while>
(qemu) migrate tcp:localhost:1025
On the same system:
qemu-system-x86_64 -hda ~/images/linux-test.img -incoming
tcp:localhost:1025
The monitor can be interacted with while waiting for an incoming live
migration.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5478 c046a42c-6fe2-441c-8c8c-71466251a162
