Commit Graph

98 Commits

Author SHA1 Message Date
Juan Quintela
b47d3af755 vmstate: Introduce VMSTATE_VARRAY_MULTPLY
This allows to send a partial array where the size is another
structure field multiplied by a constant.

Signed-off-by: Juan Quintela <quintela@redhat.com>
[PMM: updated to current master]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
2016-01-16 12:01:23 +00:00
Juan Quintela
551747491d vmstate: introduce CPU_DoubleU arrays
Add vmstate support for migrating arrays of CPU_DoubleU via
VMSTATE_CPUDOUBLE_ARRAY.

Signed-off-by: Juan Quintela <quintela@redhat.com>
[PMM: rebased, since files have all moved since 2012;
 added VMSTATE_CPUDOUBLE_ARRAY_V for consistency with FLOAT64]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
2016-01-16 12:01:23 +00:00
Dr. David Alan Gilbert
2cf0148674 Add VMSTATE_STRUCT_VARRAY_KNOWN
At the moment we have VMSTATE_STRUCT_ARRAY that requires
the field is declared as an array of fixed size.
We also have VMSTATE_STRUCT_VARRAY_UINT* that allows
a field declared as a pointer, but requires that the length
is a field member in the structure being loaded/saved.

VMSTATE_STRUCT_VARRAY_KNOWN is for arrays defined as pointers
yet we somehow know the length of.

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>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
2016-01-09 23:20:20 +02:00
Dr. David Alan Gilbert
763c906b0e Add qemu_savevm_state_complete_postcopy
Add qemu_savevm_state_complete_postcopy to complement
qemu_savevm_state_complete_precopy together with a new
save_live_complete_postcopy method on devices.

The save_live_complete_precopy method is called on
all devices during a precopy migration, and all non-postcopy
devices during a postcopy migration at the transition.

The save_live_complete_postcopy method is called at
the end of postcopy for all postcopiable devices.

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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
c31b098f64 Modify save_live_pending for postcopy
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>
2015-11-10 15:00:26 +01:00
Dr. David Alan Gilbert
a3e06c3d13 Rename save_live_complete to save_live_complete_precopy
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>
2015-11-10 14:51:49 +01:00
Liang Li
d1a8548c10 migration: rename cancel to cleanup in SaveVMHandles
'cleanup' seems more appropriate than 'cancel'.

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
2015-11-04 13:40:13 +01:00
Soren Brinkmann
eb5c936e81 vmstate: Remove redefinition of VMSTATE_UINT32_ARRAY
The macro is defined twice in identical ways.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Message-Id: <1439532987-16335-1-git-send-email-soren.brinkmann@xilinx.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-09-29 11:32:45 +05:30
Marc-André Lureau
7155f2ca9d vmstate: remove unused declaration
Since 38e0735e, register_device_unmigratable() has been removed

Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-07-27 22:44:47 +03:00
Juan Quintela
df8961522a vmstate: Create optional sections
To make sections optional, we need to do it at the beggining of the code.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-07-07 14:54:52 +02:00
Laszlo Ersek
9df0b0e09c migration: introduce VMSTATE_BUFFER_UNSAFE_INFO_TEST()
There is no _TEST() variant of VMSTATE_BUFFER_UNSAFE_INFO() yet, but we'll
soon need it. Introduce it and rebase the original
VMSTATE_BUFFER_UNSAFE_INFO() on top.

The parameter order of the new function-like macro follows that of
VMSTATE_SINGLE_TEST(): "_test" is introduced between "_state" and
"_version".

Cc: Juan Quintela <quintela@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-23 22:57:47 +02:00
Dr. David Alan Gilbert
1a8f46f8d6 Move loadvm_handlers into MigrationIncomingState
In postcopy we need the loadvm_handlers to be used in a couple
of different instances of the loadvm loop/routine, and thus
it can't be local any more.

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>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:54:01 +02:00
Juan Quintela
5cd8cadae8 migration: Use normal VMStateDescriptions for Subsections
We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription

Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:53:57 +02:00
David Gibson
87774a4a42 Add more VMSTATE_*_TEST variants for integers
Currently, vmstate.h includes helper macro variants for 8, 16 and 32-bit
unsigned integers which include a "test" function which can selectively
enable or disable the field's presence in the migration stream.

There aren't similar helpers for 64-bit unsigned integers, or any size of
signed integers.  This patch remedies this.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-09 14:59:56 +01:00
Stefan Weil
6afc14e92a migration: Fix warning caused by missing declaration of vmstate_dummy
Warning from the Sparse static analysis tool:

stubs/vmstate.c:4:26: warning:
 symbol 'vmstate_dummy' was not declared. Should it be static?

Cc: Juan Quintela <quintela@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-02-10 10:26:05 +03:00
Alexander Graf
8118f0950f migration: Append JSON description of migration stream
One of the annoyances of the current migration format is the fact that
it's not self-describing. In fact, it's not properly describing at all.
Some code randomly scattered throughout QEMU elaborates roughly how to
read and write a stream of bytes.

We discussed an idea during KVM Forum 2013 to add a JSON description of
the migration protocol itself to the migration stream. This patch
adds a section after the VM_END migration end marker that contains
description data on what the device sections of the stream are composed of.

This approach is backwards compatible with any QEMU version reading the
stream, because QEMU just stops reading after the VM_END marker and ignores
any data following it.

With an additional external program this allows us to decipher the
contents of any migration stream and hopefully make migration bugs easier
to track down.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-02-05 17:16:14 +01:00
Paolo Bonzini
e720677e32 vmstate: accept QEMUTimer in VMSTATE_TIMER*, add VMSTATE_TIMER_PTR*
Old users of VMSTATE_TIMER* are mechanically changed to VMSTATE_TIMER_PTR
variants.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-26 12:22:44 +01:00
Paolo Bonzini
a03c3e90e1 target-i386: use vmstate_offset_sub_array for AVX registers
After the next patch, each vmstate field will extract parts of a larger
(32x512-bit) array, so we cannot check the vmstate field against the
type of the array.

While changing this, change the macros to accept the index of the first
element (which will not be 0 for Hi16_ZMM_REGS) instead of the number
of elements (which is always CPU_NB_REGS).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-26 12:22:44 +01:00
Paolo Bonzini
ea987c2c21 vmstate: type-check sub-arrays
While we cannot check against the type of the full array, we can check
against the type of the fields.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-01-16 13:06:17 +05:30
Alexey Kardashevskiy
94ed706d53 vmstate: Allow dynamic allocation for VBUFFER during migration
This extends use of VMS_ALLOC flag from arrays to VBUFFER as well.

This defines VMSTATE_VBUFFER_ALLOC_UINT32 which makes use of VMS_ALLOC
and uses uint32_t type for a size.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-10-14 09:35:48 +02:00
Alexey Kardashevskiy
f32935ea22 vmstate: Add preallocation for migrating arrays (VMS_ALLOC flag)
There are few helpers already to support array migration. However they all
require the destination side to preallocate arrays before migration which
is not always possible due to unknown array size as it might be some
sort of dynamic state. One of the examples is an array of MSIX-enabled
devices in SPAPR PHB - this array may vary from 0 to 65536 entries and
its size depends on guest's ability to enable MSIX or do PCI hotplug.

This adds new VMSTATE_VARRAY_STRUCT_ALLOC macro which is pretty similar to
VMSTATE_STRUCT_VARRAY_POINTER_INT32 but it can alloc memory for migratign
array on the destination side.

This defines VMS_ALLOC flag for a field.

This changes vmstate_base_addr() to do the allocation when receiving
migration.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[agraf: drop g_malloc_n usage]
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-27 13:48:27 +02:00
Amit Shah
abfd9ce341 migration: dump vmstate info as a json file for static analysis
This commit adds a new command, '-dump-vmstate', that takes a filename
as an argument.  When executed, QEMU will dump the vmstate information
for the machine type it's invoked with to the file, and quit.

The JSON-format output can then be used to compare the vmstate info for
different QEMU versions, specifically to test whether live migration
would break due to changes in the vmstate data.

A Python script that compares the output of such JSON dumps is included
in the following commit.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-06-23 19:14:50 +02:00
Jason Wang
508e1180d3 migration: introduce self_announce_delay()
This patch introduces self_announce_delay() to calculate the delay for
the next announce round. This could be used by other device e.g
virtio-net who wants to do announcing by itself.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19 16:41:54 +03:00
Jason Wang
110f463062 migration: export SELF_ANNOUNCE_ROUNDS
Export it for other users.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-19 16:41:54 +03:00
Michael S. Tsirkin
3476436a44 vmstate: s/VMSTATE_INT32_LE/VMSTATE_INT32_POSITIVE_LE/
As the macro verifies the value is positive, rename it
to make the function clearer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 22:15:03 +02:00
Michael S. Tsirkin
4082f0889b vmstate: add VMSTATE_VALIDATE
Validate state using VMS_ARRAY with num = 0 and VMS_MUST_EXIST

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 14:15:10 +02:00
Michael S. Tsirkin
5bf81c8d63 vmstate: add VMS_MUST_EXIST
Can be used to verify a required field exists or validate
state in some other way.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05 14:15:10 +02:00
Fam Zheng
2e323f03bf scsi: Fix migration of scsi sense data
c5f52875 changed the size of sense array in vmstate_scsi_device by
mistake. This patch restores the old size, and add a subsection for the
remaining part of the buffer size. So that migration is not broken.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-03-14 10:06:55 +01:00
Christoffer Dall
a1b1d277cd vmstate: Add uint32 2D-array support
Add support for saving VMState of 2D arrays of uint32 values.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-08 14:50:48 +00:00
Peter Maydell
20bcf73fa8 vmstate: Make VMSTATE_STRUCT_POINTER take type, not ptr-to-type
The VMSTATE_STRUCT_POINTER macros are a bit odd in that they
must be passed an argument "FooType *" rather than just taking
the FooType. They're only used in one place, so it's easy to
tidy this up. This also lets us use the macro to replace the
hand-rolled VMSTATE_PTIMER.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04 15:51:45 +01:00
Peter Maydell
a1f05e79f2 vmstate: Add support for an array of ptimer_state *
Add support for defining a vmstate field which is an array
of pointers to structures, and use this to define a
VMSTATE_PTIMER_ARRAY() which allows an array of ptimer_state*
to be used by devices.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1387159292-10436-2-git-send-email-lig.fnst@cn.fujitsu.com
2013-12-17 20:12:51 +00:00
Alexey Kardashevskiy
7102400d40 migration: add version supporting macros for struct pointer
This adds version supporting macros VMSTATE_STRUCT_POINTER_TEST_V
and VMSTATE_STRUCT_POINTER_V in addition to the already existing
VMSTATE_STRUCT_POINTER and VMSTATE_STRUCT_POINTER_TEST macros.

Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-09-24 13:22:50 +02:00
Peter Maydell
ec3f8c9913 linux-user: Fix compilation failure
Fix compilation failures for linux-user targets following recent
migration related commits bd2fa51fcd and 43487c67.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1372362818-4740-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-27 15:38:35 -05:00
Peter Maydell
bd7f92e59e vmstate: Add support for two dimensional arrays
Add support for migrating two dimensional arrays, by defining
a set of new macros VMSTATE_*_2DARRAY paralleling the existing
VMSTATE_*_ARRAY macros. 2D arrays are handled the same for actual
state serialization; the only difference is that the type check
has to change for a 2D array.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Igor Mitsyanko <i.mitsyanko@gmail.com>
Message-id: 1363975375-3166-2-git-send-email-peter.maydell@linaro.org
2013-04-05 16:17:59 +01:00
Igor Mitsyanko
8070568b9a vmstate.h: introduce VMSTATE_BUFFER_POINTER_UNSAFE macro
Macro could be used to migrate a dynamically allocated buffer of known size.

Signed-off-by: Igor Mitsyanko <i.mitsyanko@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1362923278-4080-2-git-send-email-i.mitsyanko@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2013-04-05 16:17:58 +01:00
David Gibson
377e2cb96b savevm: Fix bugs in the VMSTATE_VBUFFER_MULTIPLY definition
The VMSTATE_BUFFER_MULTIPLY macro is misnamed - it actually specifies
a variably sized buffer with VMS_VBUFFER, so should be named
VMSTATE_VBUFFER_MULTIPLY.  This patch fixes this (the macro had no current
users under either name).

In addition, unlike the other VMSTATE_VBUFFER variants, this macro did not
specify VMS_POINTER.  This patch fixes this bug as well.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26 13:30:49 +01:00
David Gibson
8474a9dd67 savevm: Add VMSTATE_STRUCT_VARRAY_POINTER_UINT32
Currently the savevm code contains a VMSTATE_STRUCT_VARRAY_POINTER_INT32
helper (a variably sized array with the number of elements in an int32_t),
but not VMSTATE_STRUCT_VARRAY_POINTER_UINT32 (... with the number of
elements in a uint32_t).  This patch (trivially) fixes the deficiency.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26 13:30:49 +01:00
David Gibson
213945e4d7 savevm: Add VMSTATE_FLOAT64 helpers
The current savevm code includes VMSTATE helpers for a number of commonly
used data types, but not for the float64 type used by the internal floating
point emulation code.  This patch fixes the deficiency.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26 13:30:49 +01:00
David Gibson
d58f559834 savevm: Add VMSTATE_UINTTL_EQUAL helper
This adds an _EQUAL VMSTATE helper for target_ulongs, defined in terms of
VMSTATE_UINT32_EQUAL or VMSTATE_UINT64_EQUAL as appropriate.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26 13:30:49 +01:00
David Gibson
e344b8a16d savevm: Add VMSTATE_UINT64_EQUAL helpers
The savevm code already includes a number of *_EQUAL helpers which act as
sanity checks verifying that the configuration of the saved state matches
that of the machine we're loading into to work.  Variants already exist
for 8 bit 16 bit and 32 bit integers, but not 64 bit integers.  This patch
fills that hole, adding a UINT64 version.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-26 13:30:48 +01:00
Andreas Färber
c71c3e99b8 stubs: Add a vmstate_dummy struct for CONFIG_USER_ONLY
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-03-12 10:35:54 +01:00
Andreas Färber
d7650eab42 vmstate: Make vmstate_register() static inline
This avoids adding a duplicate stub for CONFIG_USER_ONLY.

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-03-12 10:35:54 +01:00
Paolo Bonzini
9b09503752 migration: run setup callbacks out of big lock
Only the migration_bitmap_sync() call needs the iothread lock.

Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11 13:32:01 +01:00
Paolo Bonzini
32c835ba39 migration: run pending/iterate callbacks out of big lock
This makes it possible to do blocking writes directly to the socket,
with no buffer in the middle.  For RAM, only the migration_bitmap_sync()
call needs the iothread lock.  For block migration, it is needed by
the block layer (including bdrv_drain_all and dirty bitmap access),
but because some code is shared between iterate and complete, all of
mig_save_device_dirty is run with the lock taken.

In the savevm case, the iterate callback runs within the big lock.
This is annoying because it complicates the rules.  Luckily we do not
need to do anything about it: the RAM iterate callback does not need
the iothread lock, and block migration never runs during savevm.

Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11 13:32:01 +01:00
Paolo Bonzini
8c8de19d93 migration: reorder SaveVMHandlers members
This groups together the callbacks that later will have similar
locking rules.

Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-03-11 13:32:01 +01:00
Paolo Bonzini
fd7f0d6617 hw: move fifo.[ch] to libqemuutil
fifo.c is generic code that can be easily unit tested.  So it
belongs in libqemuutil.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-03-01 13:53:10 +01:00
Juan Quintela
e4ed1541ac savevm: New save live migration method: pending
Code just now does (simplified for clarity)

    if (qemu_savevm_state_iterate(s->file) == 1) {
       vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
       qemu_savevm_state_complete(s->file);
    }

Problem here is that qemu_savevm_state_iterate() returns 1 when it
knows that remaining memory to sent takes less than max downtime.

But this means that we could end spending 2x max_downtime, one
downtime in qemu_savevm_iterate, and the other in
qemu_savevm_state_complete.

Changed code to:

    pending_size = qemu_savevm_state_pending(s->file, max_size);
    DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
    if (pending_size >= max_size) {
        ret = qemu_savevm_state_iterate(s->file);
     } else {
        vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
        qemu_savevm_state_complete(s->file);
     }

So what we do is: at current network speed, we calculate the maximum
number of bytes we can sent: max_size.

Then we ask every save_live section how much they have pending.  If
they are less than max_size, we move to complete phase, otherwise we
do an iterate one.

This makes things much simpler, because now individual sections don't
have to caluclate the bandwidth (it was implossible to do right from
there).

Signed-off-by: Juan Quintela <quintela@redhat.com>

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-20 23:09:25 +01:00
Paolo Bonzini
caf71f86a3 migration: move include files to include/migration/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:32 +01:00