Commit Graph

106 Commits

Author SHA1 Message Date
Juan Quintela
f36ada95de ram: Move xbzrle_pages into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

--

Comment why we need bytes and pages
2017-04-21 12:25:37 +02:00
Juan Quintela
07ed50a2bb ram: Move xbzrle_bytes into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
23b28c3c62 ram: Move iterations into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
29cc3d8a9b ram: Remove norm_mig_bytes_transferred
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>
2017-04-21 12:25:36 +02:00
Juan Quintela
b4d1c6e722 ram: Move norm_pages to RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
bedf53c14c ram: Remove unused pages_skipped variable
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>
2017-04-21 12:25:36 +02:00
Juan Quintela
5bb1272c38 ram: Remove unused dup_mig_bytes_transferred()
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
f7ccd61b4c ram: Move dup_pages into RAMState
Once there rename it to its actual meaning, zero_pages.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
36040d9cb2 ram: Move iterations_prev into RAMState
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>
2017-04-21 12:25:36 +02:00
Juan Quintela
b5833fde40 ram: Move xbzrle_cache_miss_prev into RAMState
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>
2017-04-21 12:25:36 +02:00
Juan Quintela
68908ed665 ram: Change num_dirty_pages_period type to uint64_t
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
a66cd90c74 ram: Move num_dirty_pages_period into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
c4bdf0cf4b ram: Change byte_xfer_{prev,now} type to uint64_t
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
eac7415958 ram: Move bytes_xfer_prev into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:36 +02:00
Juan Quintela
f664da80fc ram: Move start time into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

--

Renamed start_time to time_last_bitmap_sync(peterx suggestion)
2017-04-21 12:25:35 +02:00
Juan Quintela
5a98773896 ram: Move bitmap_sync_count into RAMState
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:35 +02:00
Juan Quintela
8d820d6f67 ram: Add dirty_rate_high_cnt to RAMState
We need to add a parameter to several functions to make this work.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-04-21 12:25:35 +02:00
Juan Quintela
6f37bb8bf3 ram: Create RAMState
We create a struct where to put all the ram state

Start with the following fields:

last_seen_block, last_sent_block, last_offset, last_version and
ram_bulk_stage are globals that are really related together.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

--

Fix typo and warnings
2017-04-21 12:25:35 +02:00
Juan Quintela
3644915726 ram: Rename block_name to rbname
So all places are consistent on the naming of a block name parameter.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-04-21 12:25:35 +02:00
Juan Quintela
5e58f968f4 ram: Rename flush_page_queue() to migration_page_queue_free()
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>
2017-04-21 12:25:35 +02:00
Juan Quintela
3d0684b2ad ram: Update all functions comments
Added doc comments for existing functions comment and rewrite them in
a common style.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

--

Fix Peter Xu comments
Improve postcopy comments as per reviews.
2017-04-21 12:25:35 +02:00
Chao Fan
1ffb5dfd35 Change the method to calculate dirty-pages-rate
In function cpu_physical_memory_sync_dirty_bitmap, file
include/exec/ram_addr.h:

if (src[idx][offset]) {
    unsigned long bits = atomic_xchg(&src[idx][offset], 0);
    unsigned long new_dirty;
    new_dirty = ~dest[k];
    dest[k] |= bits;
    new_dirty &= bits;
    num_dirty += ctpopl(new_dirty);
}

After these codes executed, only the pages not dirtied in bitmap(dest),
but dirtied in dirty_memory[DIRTY_MEMORY_MIGRATION] will be calculated.
For example:
When ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] = 0b00001111,
and atomic_rcu_read(&migration_bitmap_rcu)->bmap = 0b00000011,
the new_dirty will be 0b00001100, and this function will return 2 but not
4 which is expected.
the dirty pages in dirty_memory[DIRTY_MEMORY_MIGRATION] are all new,
so these should be calculated also.

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-03-16 08:55:56 +01:00
Dr. David Alan Gilbert
4c011c37ec postcopy: Send whole huge pages
The RAM save code uses ram_save_host_page to send whole
host pages at a time;  change this to use the host page size associated
with the RAM Block which may be a huge page.

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: <20170224182844.32452-12-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:30:24 +00:00
Dr. David Alan Gilbert
28abd20014 postcopy: Load huge pages in one go
The existing postcopy RAM load loop already ensures that it
glues together whole host-pages from the target page size chunks sent
over the wire.  Modify the definition of host page that it uses
to be the RAM block page size and thus be huge pages where appropriate.

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: <20170224182844.32452-10-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:30:23 +00:00
Dr. David Alan Gilbert
df9ff5e1e3 postcopy: Plumb pagesize down into place helpers
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>
2017-02-28 11:30:23 +00:00
Dr. David Alan Gilbert
d3a5038c46 exec: ram_block_discard_range
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>
2017-02-28 11:30:23 +00:00
Dr. David Alan Gilbert
29c5917201 postcopy: Chunk discards for hugepages
At the start of the postcopy phase, partially sent huge pages
must be discarded.  The code for dealing with host page sizes larger
than the target page size can be reused for this case.

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: <20170224182844.32452-4-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:30:23 +00:00
Dr. David Alan Gilbert
ef08fb389f postcopy: Transmit and compare individual page sizes
When using postcopy with hugepages, we require the source
and destination page sizes for any RAMBlock to match; note
that different RAMBlocks in the same VM can have different
page sizes.

Transmit them as part of the RAM information header and
fail if there's a difference.

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: <20170224182844.32452-3-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-28 11:30:23 +00:00
Dr. David Alan Gilbert
e8ca1db29b postcopy: Transmit ram size summary word
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>
2017-02-28 11:30:23 +00:00
Ashijeet Acharya
0827b9e97d migrate: Introduce zero RAM checks to skip RAM migration
Migration of a "none" machine with no RAM crashes abruptly as
bitmap_new() fails and thus aborts. Instead place zero RAM checks at
appropriate places to skip migration of RAM in this case and complete
migration successfully for devices only.

Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1486564125-31366-1-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-13 17:27:13 +00:00
Pavel Butsykin
ced1c6166e migration: discard non-dirty ram pages after the start of postcopy
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>
2017-02-13 17:27:13 +00:00
Pavel Butsykin
53f09a1076 add 'release-ram' migrate capability
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!'
2017-02-13 17:27:13 +00:00
Pavel Butsykin
9eb1476610 migration: add MigrationState arg for ram_save_/compressed_/page()
Cosmetic patch. The use of ms variable instead of migrate_get_current()
looks nicer, especially when there reuse.

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Message-Id: <20170203152321.19739-2-pbutsykin@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-13 17:27:13 +00:00
Juan Quintela
55c4446b8b migration: transform remaining DPRINTF into trace_
So we can remove DPRINTF() macro

Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1485207141-1941-2-git-send-email-quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixed up 'remained/remaining' as requested by Eric
2017-01-24 18:00:31 +00:00
Thomas Huth
5c90308f07 migration: Fix return code of ram_save_iterate()
qemu_savevm_state_iterate() expects the iterators to return 1
when they are done, and 0 if there is still something left to do.
However, ram_save_iterate() does not obey this rule and returns
the number of saved pages instead. This causes a fatal hang with
ppc64 guests when you run QEMU like this (also works with TCG):

 qemu-img create -f qcow2  /tmp/test.qcow2 1M
 qemu-system-ppc64 -nographic -nodefaults -m 256 \
                   -hda /tmp/test.qcow2 -serial mon:stdio

... then switch to the monitor by pressing CTRL-a c and try to
save a snapshot with "savevm test1" for example.

After the first iteration, ram_save_iterate() always returns 0 here,
so that qemu_savevm_state_iterate() hangs in an endless loop and you
can only "kill -9" the QEMU process.
Fix it by using proper return values in ram_save_iterate().

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2016-11-14 19:35:41 +01:00
zhanghailiang
a91246c95f COLO: Send PVM state to secondary side when do checkpoint
VM checkpointing is to synchronize the state of PVM to SVM, just
like migration does, we re-use save helpers to achieve migrating
PVM's state to Secondary side.

COLO need to cache the data of VM's state in the secondary side before
synchronize it to SVM. COLO need the size of the data to determine
how much data should be read in the secondary side.
So here, we can get the size of the data by saving it into I/O channel
before send it to the secondary side.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@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>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Amit Shah <amit@amitshah.net>
2016-10-30 15:17:39 +05:30
Vijaya Kumar K
adb65dec4b migration: Remove static allocation of xzblre cache buffer
Allocate xzblre zero page cache buffer dynamically.
Remove dependency on TARGET_PAGE_SIZE to make run-time
page size detection for arm platforms.

Signed-off-by: Vijaya Kumar K <vijayak@cavium.com>
Message-id: 1465808915-4887-2-git-send-email-vijayak@caviumnetworks.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-10-24 16:26:49 +01:00
Dr. David Alan Gilbert
2ebeaec012 Postcopy vs xbzrle: Don't send xbzrle pages once in postcopy [for 2.8]
xbzrle relies on reading pages that have already been sent
to the destination and then applying the modifications; we can't
do that in postcopy because the destination may well have
modified the page already or the page has been discarded.

I already didn't allow reception of xbzrle pages, but I
forgot to add the test to stop them being sent.

Enabling both xbzrle and postcopy can make some sense;
if you think that your migration might finish if you
have xbzrle, then when it doesn't complete you flick
over to postcopy and stop xbzrle'ing.

This corresponds to RH bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1368422

Symptom is:

Unknown combination of migration flags: 0x60 (postcopy mode)
(either 0x60 or 0x40)

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>
2016-10-13 17:23:53 +02:00
Paolo Bonzini
9c1f8f4493 migration: sync all address spaces
Migrating a VM during reboot sometimes results in differences
between the source and destination in the SMRAM area.

This is because migration_bitmap_sync() only fetches from KVM
the dirty log of address_space_memory.  SMRAM memory slots
are ignored and the modifications to SMRAM are not sent to the
destination.

Reported-by: He Rongguang <herongguang.he@huawei.com>
Reviewed-by: He Rongguang <herongguang.he@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-27 11:57:29 +02:00
Richard Henderson
a1febc4950 cutils: Export only buffer_is_zero
Since the two users don't make use of the returned offset,
beyond ensuring that the entire buffer is zero, consider the
can_use_buffer_find_nonzero_offset and buffer_find_nonzero_offset
functions internal.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1472496380-19706-4-git-send-email-rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-13 19:09:45 +02:00
Cao jin
e110aa919a migration/ram: fix typo
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Message-Id: <1469776231-23820-1-git-send-email-caoj.fnst@cn.fujitsu.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-08-11 16:59:33 +05:30
Liang Li
0d9f9a5c52 migration: code clean up
Use 'QemuMutex comp_done_lock' and 'QemuCond comp_done_cond' instead
of 'QemuMutex *comp_done_lock' and 'QemuCond comp_done_cond'. To keep
consistent with 'QemuMutex decomp_done_lock' and
'QemuCond comp_done_cond'.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-10-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:31 +05:30
Liang Li
33d151f418 migration: refine the decompression code
The current code for multi-thread decompression is not clear,
especially in the aspect of using lock. Refine the code
to make it clear.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-9-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:28 +05:30
Liang Li
a7a9a88f9d migration: refine the compression code
The current code for multi-thread compression is not clear,
especially in the aspect of using lock. Refine the code
to make it clear.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-8-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:26 +05:30
Liang Li
90e56fb46d migration: protect the quit flag by lock
quit_comp_thread and quit_decomp_thread are accessed by several
thread, it's better to protect them with locks. We use a per
thread flag to replace the global one, and the new flag is protected
by a lock.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-7-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:23 +05:30
Liang Li
fc50438ed0 migration: refine ram_save_compressed_page
Use qemu_put_compression_data to do the compression directly
instead of using do_compress_ram_page, avoid some data copy.
very small improvement, at the same time, add code to check
if the compression is successful.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-6-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:21 +05:30
Liang Li
b3be28969b qemu-file: Fix qemu_put_compression_data flaw
Current qemu_put_compression_data can only work with no writable
QEMUFile, and can't work with the writable QEMUFile. But it does
not provide any measure to prevent users from using it with a
writable QEMUFile.

We should fix this flaw to make it works with writable QEMUFile.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Suggested-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1462433579-13691-5-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:18 +05:30
Liang Li
e7bb92e21a migration: remove useless code
page_buffer is set twice repeatedly, remove the previous set.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1462433579-13691-4-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:14 +05:30
Liang Li
5533b2e9bc migration: Fix a potential issue
At the end of live migration and before vm_start() on the destination
side, we should make sure all the decompression tasks are finished, if
this can not be guaranteed, the VM may get the incorrect memory data,
or the updated memory may be overwritten by the decompression thread.
Add the code to fix this potential issue.

Suggested-by: David Alan Gilbert <dgilbert@redhat.com>
Suggested-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-3-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:09 +05:30
Liang Li
73a8912b8a migration: Fix multi-thread compression bug
Recently, a bug related to multiple thread compression feature for
live migration is reported. The destination side will be blocked
during live migration if there are heavy workload in host and
memory intensive workload in guest, this is most likely to happen
when there is one decompression thread.

Some parts of the decompression code are incorrect:
1. The main thread receives data from source side will enter a busy
loop to wait for a free decompression thread.
2. A lock is needed to protect the decomp_param[idx]->start, because
it is checked in the main thread and is updated in the decompression
thread.

Fix these two issues by following the code pattern for compression.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Reported-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Daniel P. Berrange <berrange@redhat.com>

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-2-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:01 +05:30