Commit Graph

497 Commits

Author SHA1 Message Date
Paolo Bonzini
4987783400 migration: fix incorrect memory_global_dirty_log_start outside BQL
This can cause various segmentation faults or aborts in qemu-iotests
test 091.

Fixes: 5b82b703b6
Cc: Dave Gilbert <dgilbert@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 15:34:43 +01:00
Stefan Hajnoczi
5b82b703b6 memory: RCU ram_list.dirty_memory[] for safe RAM hotplug
Although accesses to ram_list.dirty_memory[] use atomics so multiple
threads can safely dirty the bitmap, the data structure is not fully
thread-safe yet.

This patch handles the RAM hotplug case where ram_list.dirty_memory[] is
grown.  ram_list.dirty_memory[] is change from a regular bitmap to an
RCU array of pointers to fixed-size bitmap blocks.  Threads can continue
accessing bitmap blocks while the array is being extended.  See the
comments in the code for an in-depth explanation of struct
DirtyMemoryBlocks.

I have tested that live migration with virtio-blk dataplane works.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1453728801-5398-2-git-send-email-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-09 15:45:26 +01:00
zhanghailiang
a08f689034 migration/ram: Fix some helper functions' parameter to use PageSearchStatus
Some helper functions use parameters 'RAMBlock *block' and 'ram_addr_t *offset',
We can use 'PageSearchStatus *pss' directly instead, with this change, we
can reduce the number of parameters for these helper function, also
it is easily to add new parameters for these helper functions.

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: <1452829066-9764-5-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-02-05 19:09:50 +05:30
zhanghailiang
4c4bad4861 ram: Split host_from_stream_offset() into two helper functions
Split host_from_stream_offset() into two parts:
One is to get ram block, which the block idstr may be get from migration
stream, the other is to get hva (host) address from block and the offset.
Besides, we will do the check working in a new helper offset_in_ramblock().

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: <1452829066-9764-2-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-02-05 19:09:50 +05:30
Peter Maydell
1393a48526 migration: Clean up includes
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
2016-01-29 15:07:22 +00:00
Peter Maydell
d341d9f306 fpu: Replace uint8 typedef with uint8_t
Replace the uint8 softfloat-specific typedef with uint8_t.
This change was made with

find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint8\b/uint8_t/g'

together with manual removal of the typedef definition and
manual fixing of more erroneous uses found via test compilation.

It turns out that the only code using this type is an accidental
use where uint8_t was intended anyway...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-7-git-send-email-peter.maydell@linaro.org
2016-01-22 15:09:21 +00:00
Peter Maydell
17c8a21978 Error reporting patches for 2016-01-13
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJWll18AAoJEDhwtADrkYZTLL8QAKB2zTF8/9QwIA46T/nNuQKV
 ZckiADC6Aeh0Ksu5DAS7fZmfgPDmlwYYCN3x5KGeKGKIIPiVrddEYwyHqa6eTCOu
 pbJBu5WeVamre8/9SH7u2VC/RMU0OZ+OhhJJf174Fc2mTALDtK1JJO4kXCzSUA5V
 Iop04YtliH5dnDhCdIHH2tByDLMf1Iaq8NYJ0xWb3btNGX6iIT8F3EsbD9rGiE1m
 c+F0qPRFDIrE+OseafrTHeKy/4D9biWnP9CmOGv49m+OxqYs33B26DhaIq41TvYv
 /1sECCz2GmIFbpL1B0MvxNjKtj08btrz4EkpU4YBHxK+8EhOX2nJdfrZEhcone7A
 c92esN8ATFbsG3AP1Vnt/dxG0YzQB8/azGP/MgVczYaj0m7WZ89etqendj1GeYAZ
 2xXewICcmexBeMOodxthHxyQaUQ9oZyk8+sK5T9O6JKvb3uCHKJ6MeRwurHUEtL8
 rzPLzKw8Tdalfa7AhQevVquH0QCmm4IEUC7xalHmfsFuqqTU95zfLa+DbdhzdIG+
 KdRkCv4+yX8//kUM5LwiqSd7ruMDEMQPQz3pbegrKrUJDCcTt5TccZ6NxiccCpC3
 6YXaUG2HqBNH5hznhR1Lf+gRdLeCW8WjI3fWHsAuyTGvl6z8qHm5/Q944UrIlJ8A
 Ea1BUSMwgFqx5xp6KYjB
 =OVhB
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2016-01-13' into staging

Error reporting patches for 2016-01-13

# gpg: Signature made Wed 13 Jan 2016 14:21:48 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-error-2016-01-13: (41 commits)
  checkpatch: Detect newlines in error_report and other error functions
  error: Consistently name Error * objects err, and not errp
  s390/sclp: Simplify control flow in sclp_realize()
  hw/s390x: Rename local variables Error *l_err to just err
  error: Clean up errors with embedded newlines (again)
  vhdx: Fix "log that needs to be replayed" error message
  pci-assign: Clean up "Failed to assign" error messages
  vmdk: Clean up "Invalid extent lines" error message
  vmdk: Clean up control flow in vmdk_parse_extents() a bit
  error: Strip trailing '\n' from error string arguments (again)
  qemu-io qemu-nbd: Use error_report() etc. instead of fprintf()
  migration: Use error_reportf_err() instead of monitor_printf()
  spapr: Use error_reportf_err()
  error: Use error_prepend() where it makes obvious sense
  error: Use error_reportf_err() where it makes obvious sense
  error: Don't decorate original error message when adding to it
  error: New error_prepend(), error_reportf_err()
  test-throttle: Simplify qemu_init_main_loop() error handling
  qemu-nbd: Clean up "Failed to load snapshot" error message
  block: Clean up "Could not create temporary overlay" error message
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-01-14 13:07:38 +00:00
Markus Armbruster
9af9e0fed7 error: Strip trailing '\n' from error string arguments (again)
Commit 6daf194d, be62a2eb and 312fd5f got rid of a bunch, but they
keep coming back.  Tracked down with the Coccinelle semantic patch
from commit 312fd5f.

Cc: Fam Zheng <famz@redhat.com>
Cc: Peter Crosthwaite <crosthwaitepeter@gmail.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Changchun Ouyang <changchun.ouyang@intel.com>
Cc: zhanghailiang <zhang.zhanghailiang@huawei.com>
Cc: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Acked-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1450452927-8346-17-git-send-email-armbru@redhat.com>
2016-01-13 15:16:18 +01:00
Dr. David Alan Gilbert
c1bc66263c multithread decompression: Avoid one copy
qemu_get_buffer does a copy, we can avoid the memcpy, and
we can then remove the extra buffer.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1450266458-3178-7-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-01-13 16:03:01 +05:30
Dr. David Alan Gilbert
063e760a5f Use qemu_get_buffer_in_place for xbzrle data
Avoid a data copy (if we're lucky) in the xbzrle code.

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: <1450266458-3178-6-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-01-13 16:02:37 +05:30
Dr. David Alan Gilbert
4addcd4fdc Migration: Emit event at start of pass
Emit an event each time we sync the dirty bitmap on the source;
this helps libvirt use postcopy by giving it a kick when it
might be a good idea to start the postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1450266458-3178-5-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-01-13 16:02:13 +05:30
Dr. David Alan Gilbert
3fd3c4b37c Fix xbzrle vs last_sent_block update
My fix (84e7b80a) replaced the last_sent_block update that I'd
removed earlier; however it was too aggressive in the xbzrle case.

save_xbzrle_page might return '0' to mean that the page didn't
need sending since it was the same as the last sent version;
in this case we can't update 'last_sent_block' since we didn't
actually send it.

Symptom: 'Illegal RAM offset 1018000' as we try and send a page
        to the wrong RAMBlock;  potentially that could be a data
        corruption if you were really unlucky.

Fixes: 84e7b80a05

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-id: 1449765106-6528-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-12-11 12:51:27 +00:00
Dr. David Alan Gilbert
84e7b80a05 Set last_sent_block
In a82d593b61 I accidentally removed the setting of
last_sent_block,  put it back.

Symptoms:
  Multithreaded compression only uses one thread.
  Migration is a bit less efficient since it won't use 'cont' flags.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: a82d593b61
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-11-19 11:49:53 +01:00
Dr. David Alan Gilbert
a3b6ff6d0a Postcopy: Fix TP!=HP zero case
Where the target page size is different from the host page
we special case it, but I messed up on the zero case check.

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>
2015-11-12 17:52:29 +01:00
Juan Quintela
9458ad6b44 migration: print ram_addr_t as RAM_ADDR_FMT not %zx
Not all the wold is 64bits (yet).

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-11-12 17:52:29 +01:00
Dr. David Alan Gilbert
99e314ebca Host page!=target page: Cleanup bitmaps
Prior to the start of postcopy, ensure that everything that will
be transferred later is a whole host-page in size.

This is accomplished by discarding partially transferred host pages
and marking any that are partially dirty as fully dirty.

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>
2015-11-10 15:00:28 +01:00
Dr. David Alan Gilbert
663e6c1df8 Don't sync dirty bitmaps in postcopy
Once we're in postcopy the source processors are stopped and memory
shouldn't change any more, so there's no need to look at the dirty
map.

There are two notes to this:
  1) If we do resync and a page had changed then the page would get
     sent again, which the destination wouldn't allow (since it might
     have also modified the page)
  2) Before disabling this I'd seen very rare cases where a page had been
     marked dirtied although the memory contents are apparently identical

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>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-11-10 15:00:28 +01:00
Dr. David Alan Gilbert
c53b7ddc61 postcopy: Check order of received target pages
Ensure that target pages received within a host page are in order.
This shouldn't trigger, but in the cases where the sender goes
wrong and sends stuff out of order it produces a corruption that's
really nasty to debug.

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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
a71808772a Postcopy: Use helpers to map pages during migration
In postcopy, the destination guest is running at the same time
as it's receiving pages; as we receive new pages we must put
them into the guests address space atomically to avoid a running
CPU accessing a partially written page.

Use the helpers in postcopy-ram.c to map these pages.

qemu_get_buffer_in_place is used to avoid a copy out of qemu_file
in the case that postcopy is going to do a copy anyway.

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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
a82d593b61 Page request: Consume pages off the post-copy queue
When transmitting RAM pages, consume pages that have been queued by
MIG_RPCOMM_REQPAGE commands and send them ahead of normal page scanning.

Note:
  a) After a queued page the linear walk carries on from after the
unqueued page; there is a reasonable chance that the destination
was about to ask for other closeby pages anyway.

  b) We have to be careful of any assumptions that the page walking
code makes, in particular it does some short cuts on its first linear
walk that break as soon as we do a queued page.

  c) We have to be careful to not break up host-page size chunks, since
this makes it harder to place the pages on the destination.

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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
6c595cdee1 Page request: Process incoming page request
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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
1caddf8a81 postcopy: Incoming initialisation
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
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 15:00:27 +01:00
Dr. David Alan Gilbert
e0b266f01d migration_completion: Take current state
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>
2015-11-10 15:00:27 +01:00
Dr. David Alan Gilbert
f3f491fcd6 Postcopy: Maintain unsentmap
Maintain an 'unsentmap' of pages that have yet to be sent.
This is used in the following patches to discard some set of
the pages already sent as we enter postcopy mode.

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>
2015-11-10 15:00:27 +01:00
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
Dr. David Alan Gilbert
a776aa15a7 ram_load: Factor out host_from_stream_offset call and check
The main RAM load loop has a call to host_from_stream_offset for
each page type that actually loads data with the same test;
factor it out before the switch.

The host = NULL is to silence a bogus gcc warning of
an unitialised in the RAM_SAVE_COMPRESS_PAGE case, it
doesn't seem to realise that host is always initialised by the if at
the top in the cases the switch takes.

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>
2015-11-10 14:51:49 +01:00
Dr. David Alan Gilbert
4f2e425267 ram_debug_dump_bitmap: Dump a migration bitmap as text
Useful for debugging the migration bitmap and other bitmaps
of the same format (including the sentmap in postcopy).

The bitmap is printed to stderr.
Lines that are all the expected value are excluded so the output
can be quite compact for many bitmaps.

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 14:51:48 +01:00
Dr. David Alan Gilbert
e3dd74934f qemu_ram_block_by_name
Add a function to find a RAMBlock by name; use it in two
of the places that already open code that loop; we've
got another use later in postcopy.

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>
2015-11-10 14:51:48 +01:00
Liang Li
6ad2a215e7 migration: code clean up
Just clean up code, no behavior change.

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
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
Liang Li
94f5a43704 migration: defer migration_end & blk_mig_cleanup
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
2015-11-04 13:40:13 +01:00
Denis V. Lunev
60be634079 migration: fix deadlock
Release qemu global mutex before call synchronize_rcu().
synchronize_rcu() waiting for all readers to finish their critical
sections. There is at least one critical section in which we try
to get QGM (critical section is in address_space_rw() and
prepare_mmio_access() is trying to aquire QGM).

Both functions (migration_end() and migration_bitmap_extend())
are called from main thread which is holding QGM.

Thus there is a race condition that ends up with deadlock:
main thread     working thread
Lock QGA                |
|             Call KVM_EXIT_IO handler
|                       |
|        Open rcu reader's critical section
Migration cleanup bh    |
|                       |
synchronize_rcu() is    |
waiting for readers     |
|            prepare_mmio_access() is waiting for QGM
  \                   /
         deadlock

The patch changes bitmap freeing from direct g_free after synchronize_rcu
to free inside call_rcu.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reported-by: Igor Redko <redkoi@virtuozzo.com>
Tested-by: Igor Redko <redkoi@virtuozzo.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

CC: Anna Melekhova <annam@virtuozzo.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Wen Congyang <wency@cn.fujitsu.com>
2015-10-15 08:14:13 +02:00
Jason J. Herne
070afca258 migration: Dynamic cpu throttling for auto-converge
Remove traditional auto-converge static 30ms throttling code and replace it
with a dynamic throttling algorithm.

Additionally, be more aggressive when deciding when to start throttling.
Previously we waited until four unproductive memory passes. Now we begin
throttling after only two unproductive memory passes. Four seemed quite
arbitrary and only waiting for two passes allows us to complete the migration
faster.

Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
2015-09-30 09:42:04 +02:00
Dr. David Alan Gilbert
b9e6092814 ram_find_and_save_block: Split out the finding
Split out the finding of the dirty page and all the wrap detection
into a separate function since it was getting a bit hairy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1443018431-11170-3-git-send-email-dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>

[Fix comment -- Amit]
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-09-29 11:38:29 +05:30
Dr. David Alan Gilbert
b8fb8cb748 Move dirty page search state into separate structure
Pull the search state for one iteration of the dirty page
search into a structure.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1443018431-11170-2-git-send-email-dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-09-29 11:37:07 +05:30
Dr. David Alan Gilbert
2f68e39956 migration/ram.c: Use RAMBlock rather than MemoryRegion
RAM migration mainly works on RAMBlocks but in a few places
uses data from MemoryRegions to access the same information that's
already held in RAMBlocks; clean it up just to avoid the
MemoryRegion use.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1439463094-5394-2-git-send-email-dgilbert@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-09-29 11:33:02 +05:30
Liang Li
9f5f380b54 migration: reduce the count of strlen call
'strlen' is called three times in 'save_page_header', it's
inefficient.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-07-15 12:21:28 +02:00
Paolo Bonzini
d09a6fde15 migration: fix RCU deadlock
migration_end calls synchronize_rcu() within a critical section.
That causes a deadlock; move the call after rcu_read_unlock().

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-09 08:47:58 +02:00
Li Zhijian
dd63169766 migration: extend migration_bitmap
Prevously, if we hotplug a device(e.g. device_add e1000) during
migration is processing in source side, qemu will add a new ram
block but migration_bitmap is not extended.
In this case, migration_bitmap will overflow and lead qemu abort
unexpectedly.

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-07-07 14:54:56 +02:00
Li Zhijian
2ff64038a5 migration: protect migration_bitmap
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-07-07 14:54:56 +02:00
Dr. David Alan Gilbert
632e3a5cd8 Rework ram_control_load_hook to hook during block load
We need the names of RAMBlocks as they're loaded for RDMA,
reuse a slightly modified ram_control_load_hook:
  a) Pass a 'data' parameter to use for the name in the block-reg
     case
  b) Only some hook types now require the presence of a hook function.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-07-07 14:54:48 +02:00
zhanghailiang
5ee6926582 arch_init: Clean up the duplicate variable 'len' defining in ram_load()
There are two places that define 'len' variable, It's OK for compiling,
but makes it difficult for reading.

Remove the local one which defined in the inside 'while' loop.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-06-12 06:42:34 +02:00
Juan Quintela
7205c9ec52 migration: reduce include files
To make changes easier, with the copy, I maintained almost all include
files.  Now I remove the unnecessary ones on this patch.  This compiles
on linux x64 with all architectures configured, and cross-compiles for
windows 32 and 64 bits.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-12 06:42:34 +02:00
Juan Quintela
76cc7b587f migration: Add myself to the copyright list of both files
If anyone feels like adding himself to the list, just sent me a patch.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-12 06:42:34 +02:00
Juan Quintela
56e93d26b8 migration: move ram stuff to migration/ram
For historic reasons, ram migration have been on arch_init.c.  Just
split it into migration/ram.c, the same that happened with block.c.

There is only code movement, no changes altogether.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-12 06:40:59 +02:00