Commit Graph

449 Commits

Author SHA1 Message Date
Andrey Gruzdev 82ea3e3b99 migration: Rename 'bs' to 'block' in background snapshot code
Rename 'bs' to commonly used 'block' in migration/ram.c background
snapshot code.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-5-andrey.gruzdev@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-04-07 18:37:56 +01:00
Andrey Gruzdev eeccb99c9d migration: Pre-fault memory before starting background snasphot
This commit solves the issue with userfault_fd WP feature that
background snapshot is based on. For any never poluated or discarded
memory page, the UFFDIO_WRITEPROTECT ioctl() would skip updating
PTE for that page, thereby loosing WP setting for it.

So we need to pre-fault pages for each RAM block to be protected
before making a userfault_fd wr-protect ioctl().

Fixes: 278e2f551a (migration: support
  UFFD write fault processing in ram_save_iterate())
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-4-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert:
  Bodged ifdef __linux__ on ram_write_tracking_prepare, should really
      go in a stub
2021-04-07 18:37:28 +01:00
Daniel P. Berrangé cbde7be900 migrate: remove QMP/HMP commands for speed, downtime and cache size
The generic 'migrate_set_parameters' command handle all types of param.

Only the QMP commands were documented in the deprecations page, but the
rationale for deprecating applies equally to HMP, and the replacements
exist. Furthermore the HMP commands are just shims to the QMP commands,
so removing the latter breaks the former unless they get re-implemented.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2021-03-18 09:22:55 +00:00
Mahmoud Mandour 373969507a migration: Replaced qemu_mutex_lock calls with QEMU_LOCK_GUARD
Replaced various qemu_mutex_lock calls and their respective
qemu_mutex_unlock calls with QEMU_LOCK_GUARD macro. This simplifies
the code by eliminating the respective qemu_mutex_unlock calls.

Signed-off-by: Mahmoud Mandour <ma.mandourr@gmail.com>
Message-Id: <20210311031538.5325-7-ma.mandourr@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-03-15 20:01:55 +00:00
Stefan Reiter e846b74650 migration: only check page size match if RAM postcopy is enabled
Postcopy may also be advised for dirty-bitmap migration only, in which
case the remote page size will not be available and we'll instead read
bogus data, blocking migration with a mismatch error if the VM uses
hugepages.

Fixes: 58110f0acb ("migration: split common postcopy out of ram postcopy")
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Message-Id: <20210204163522.13291-1-s.reiter@proxmox.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:52 +00:00
Markus Armbruster 8b9407a09f migration: Clean up signed vs. unsigned XBZRLE cache-size
73af8dd8d7 "migration: Make xbzrle_cache_size a migration
parameter" (v2.11.0) made the new parameter unsigned (QAPI type
'size', uint64_t in C).  It neglected to update existing code, which
continues to use int64_t.

migrate_xbzrle_cache_size() returns the new parameter.  Adjust its
return type.

QMP query-migrate-cache-size returns migrate_xbzrle_cache_size().
Adjust its return type.

migrate-set-parameters passes the new parameter to
xbzrle_cache_resize().  Adjust its parameter type.

xbzrle_cache_resize() passes it on to cache_init().  Adjust its
parameter type.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210202141734.2488076-3-armbru@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Andrey Gruzdev 278e2f551a migration: support UFFD write fault processing in ram_save_iterate()
In this particular implementation the same single migration
thread is responsible for both normal linear dirty page
migration and procesing UFFD page fault events.

Processing write faults includes reading UFFD file descriptor,
finding respective RAM block and saving faulting page to
the migration stream. After page has been saved, write protection
can be removed. Since asynchronous version of qemu_put_buffer()
is expected to be used to save pages, we also have to flush
migraion stream prior to un-protecting saved memory range.

Write protection is being removed for any previously protected
memory chunk that has hit the migration stream. That's valid
for pages from linear page scan along with write fault pages.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210129101407.103458-4-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  fixup pagefault.address cast for 32bit
2021-02-08 11:19:51 +00:00
Andrey Gruzdev 6e8c25b4c6 migration: introduce 'background-snapshot' migration capability
Add new capability to 'qapi/migration.json' schema.
Update migrate_caps_check() to validate enabled capability set
against introduced one. Perform checks for required kernel features
and compatibility with guest memory backends.

Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210129101407.103458-2-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00
Philippe Mathieu-Daudé af3bbbe984 migration/ram: Fix hexadecimal format string specifier
The '%u' conversion specifier is for decimal notation.
When prefixing a format with '0x', we want the hexadecimal
specifier ('%x').

Inspired-by: Dov Murik <dovmurik@linux.vnet.ibm.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20201103112558.2554390-5-philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-11-12 14:02:41 +00:00
Rao, Lei b70cb3b485 Reduce the time of checkpoint for COLO
we should set ram_bulk_stage to false after ram_state_init,
otherwise the bitmap will be unused in migration_bitmap_find_dirty.
all pages in ram cache will be flushed to the ram of secondary guest
for each checkpoint.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Signed-off-by: Derek Su <dereksu@qnap.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2020-11-11 16:52:23 +08:00
Bihong Yu 49324e939c migration: Do not initialise statics and globals to 0 or NULL
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1603163448-27122-7-git-send-email-yubihong@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Bihong Yu f4c51a6bfd migration: Add braces {} for if statement
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1603163448-27122-6-git-send-email-yubihong@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Bihong Yu 395cb45009 migration: Add spaces around operator
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1603163448-27122-4-git-send-email-yubihong@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Bihong Yu 29fccade10 migration: Don't use '#' flag of printf format
Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1603163448-27122-3-git-send-email-yubihong@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-10-26 16:15:04 +00:00
Chuan Zheng 3ded54b1bd migration/dirtyrate: move RAMBLOCK_FOREACH_MIGRATABLE into ram.h
RAMBLOCK_FOREACH_MIGRATABLE is need in dirtyrate measure,
move the existing definition up into migration/ram.h

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Message-Id: <1600237327-33618-6-git-send-email-zhengchuan@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-09-25 12:45:57 +01:00
zhaolichang 3a4452d896 migration/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the migration folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200917075029.313-3-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:36:32 +02:00
Claudio Fontana b0c3cf9407 cpu-throttle: new module, extracted from cpus.c
move the vcpu throttling functionality into its own module.

This functionality is not specific to any accelerator,
and it is used currently by migration to slow down guests to try to
have migrations converge, and by the cocoa MacOS UI to throttle speed.

cpu-throttle contains the controls to adjust and inspect throttle
settings, start (set) and stop vcpu throttling, and the throttling
function itself that is run periodically on vcpus to make them take a nap.

Execution of the throttling function on all vcpus is triggered by a timer,
registered at module initialization.

No functionality change.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20200629093504.3228-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10 18:04:49 -04:00
Keqian Zhu fb6135807f migration: Count new_dirty instead of real_dirty
real_dirty_pages becomes equal to total ram size after dirty log sync
in ram_init_bitmaps, the reason is that the bitmap of ramblock is
initialized to be all set, so old path counts them as "real dirty" at
beginning.

This causes wrong dirty rate and false positive throttling.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Message-Id: <20200622032037.31112-1-zhukeqian1@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-07-03 16:23:05 +01:00
Wei Wang 9227140217 migration: fix xbzrle encoding rate calculation
It's reported an error of implicit conversion from "unsigned long" to
"double" when compiling with Clang 10. Simply make the encoding rate 0
when the encoded_size is 0.

Fixes: e460a4b1a4
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reported-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200617201309.1640952-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-06-18 10:26:02 +01:00
Lukas Straub 24fa16f8cc migration/colo.c: Flush ram cache only after receiving device state
If we suceed in receiving ram state, but fail receiving the device
state, there will be a mismatch between the two.

Fix this by flushing the ram cache only after the vmstate has been
received.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Message-Id: <3289d007d494cb0e2f05b1cf4ae6a78d300fede3.1589193382.git.lukasstraub2@web.de>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-06-01 18:44:27 +01:00
Wei Wang e460a4b1a4 migration/xbzrle: add encoding rate
Users may need to check the xbzrle encoding rate to know if the guest
memory is xbzrle encoding-friendly, and dynamically turn off the
encoding if the encoding rate is low.

Signed-off-by: Yi Sun <yi.y.sun@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Message-Id: <1588208375-19556-1-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00
David Hildenbrand ddf35bdf0a migration/ram: Consolidate variable reset after placement in ram_load_postcopy()
Let's consolidate resetting the variables.

Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200421085300.7734-10-david@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Fixup for context conflicts with 91ba442
2020-05-07 17:40:24 +01:00
Keqian Zhu cbbf818224 migration/throttle: Add cpu-throttle-tailslow migration parameter
At the tail stage of throttling, the Guest is very sensitive to
CPU percentage while the @cpu-throttle-increment is excessive
usually at tail stage.

If this parameter is true, we will compute the ideal CPU percentage
used by the Guest, which may exactly make the dirty rate match the
dirty rate threshold. Then we will choose a smaller throttle increment
between the one specified by @cpu-throttle-increment and the one
generated by ideal CPU percentage.

Therefore, it is compatible to traditional throttling, meanwhile
the throttle increment won't be excessive at tail stage. This may
make migration time longer, and is disabled by default.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Message-Id: <20200413101508.54793-1-zhukeqian1@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-05-07 17:40:24 +01:00
Peter Maydell a2261b2754 trivial patches (20200504)
Silent static analyzer warning
 Remove dead assignments
 Support -chardev serial on macOS
 Update MAINTAINERS
 Some cosmetic changes
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Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-for-5.1-pull-request' into staging

trivial patches (20200504)

Silent static analyzer warning
Remove dead assignments
Support -chardev serial on macOS
Update MAINTAINERS
Some cosmetic changes

# gpg: Signature made Mon 04 May 2020 16:45:18 BST
# gpg:                using RSA key CD2F75DDC8E3A4DC2E4F5173F30C38BD3F2FBE3C
# gpg:                issuer "laurent@vivier.eu"
# gpg: Good signature from "Laurent Vivier <lvivier@redhat.com>" [full]
# gpg:                 aka "Laurent Vivier <laurent@vivier.eu>" [full]
# gpg:                 aka "Laurent Vivier (Red Hat) <lvivier@redhat.com>" [full]
# Primary key fingerprint: CD2F 75DD C8E3 A4DC 2E4F  5173 F30C 38BD 3F2F BE3C

* remotes/vivier2/tags/trivial-branch-for-5.1-pull-request:
  hw/timer/pxa2xx_timer: Add assertion to silent static analyzer warning
  hw/timer/stm32f2xx_timer: Remove dead assignment
  hw/gpio/aspeed_gpio: Remove dead assignment
  hw/isa/i82378: Remove dead assignment
  hw/ide/sii3112: Remove dead assignment
  hw/input/adb-kbd: Remove dead assignment
  hw/i2c/pm_smbus: Remove dead assignment
  blockdev: Remove dead assignment
  block: Avoid dead assignment
  Compress lines for immediate return
  chardev: Add macOS to list of OSes that support -chardev serial
  MAINTAINERS: Update Keith Busch's email address
  elf_ops: Don't try to g_mapped_file_unref(NULL)
  hw/mem/pc-dimm: Fix line over 80 characters warning
  hw/mem/pc-dimm: Print slot number on error at pc_dimm_pre_plug()
  MAINTAINERS: Mark the LatticeMico32 target as orphan
  timer/exynos4210_mct: Remove redundant statement in exynos4210_mct_write()
  display/blizzard: use extract16() for fix clang analyzer warning in blizzard_draw_line16_32()
  scsi/esp-pci: add g_assert() for fix clang analyzer warning in esp_pci_io_write()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-05-05 14:03:28 +01:00
Daniel Brodsky 6e8a355de6 lockable: replaced locks with lock guard macros where appropriate
- ran regexp "qemu_mutex_lock\(.*\).*\n.*if" to find targets
- replaced result with QEMU_LOCK_GUARD if all unlocks at function end
- replaced result with WITH_QEMU_LOCK_GUARD if unlock not at end

Signed-off-by: Daniel Brodsky <dnbrdsky@gmail.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-id: 20200404042108.389635-3-dnbrdsky@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-05-04 16:07:43 +01:00
Simran Singhal b3ac2b94cd Compress lines for immediate return
Compress two lines into a single line if immediate return statement is found.

It also remove variables progress, val, data, ret and sock
as they are no longer needed.

Remove space between function "mixer_load" and '(' to fix the
checkpatch.pl error:-
ERROR: space prohibited between function name and open parenthesis '('

Done using following coccinelle script:
@@
local idexpression ret;
expression e;
@@

-ret =
+return
     e;
-return ret;

Signed-off-by: Simran Singhal <singhalsimran0@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200401165314.GA3213@simran-Inspiron-5558>
[lv: in handle_aiocb_write_zeroes_unmap() move "int ret" inside the #ifdef]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-05-04 14:43:22 +02:00
Vladimir Sementsov-Ogievskiy b4a1733c5e migration/ram: fix use after free of local_err
local_err is used again in migration_bitmap_sync_precopy() after
precopy_notify(), so we must zero it. Otherwise try to set
non-NULL local_err will crash.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200324153630.11882-6-vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-25 12:31:38 +00:00
zhanghailiang 8af66371ed ram/colo: only record bitmap of dirty pages in COLO stage
It is only need to record bitmap of dirty pages while goes
into COLO stage.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-Id: <20200224065414.36524-6-zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-13 09:36:30 +00:00
zhanghailiang 0393031a16 COLO: Optimize memory back-up process
This patch will reduce the downtime of VM for the initial process,
Previously, we copied all these memory in preparing stage of COLO
while we need to stop VM, which is a time-consuming process.
Here we optimize it by a trick, back-up every page while in migration
process while COLO is enabled, though it affects the speed of the
migration, but it obviously reduce the downtime of back-up all SVM'S
memory in COLO preparing stage.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-Id: <20200224065414.36524-5-zhang.zhanghailiang@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  minor typo fixes
2020-03-13 09:36:30 +00:00
Keqian Zhu dc14a47076 migration/throttle: Add throttle-trig-thres migration parameter
Currently, if the bytes_dirty_period is more than the 50% of
bytes_xfer_period, we start or increase throttling.

If we make this percentage higher, then we can tolerate higher
dirty rate during migration, which means less impact on guest.
The side effect of higher percentage is longer migration time.
We can make this parameter configurable to switch between mig-
ration time first or guest performance first.

The default value is 50 and valid range is 1 to 100.

Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Message-Id: <20200224023142.39360-1-zhukeqian1@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-03-13 09:36:30 +00:00
Juan Quintela 87dc6f5f66 multifd: Add zstd compression multifd support
Signed-off-by: Juan Quintela <quintela@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-02-28 09:25:49 +01:00
Juan Quintela ab7cbb0b9a multifd: Make no compression operations into its own structure
It will be used later.

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

---

No comp value needs to be zero.
2020-02-28 09:24:43 +01:00
Juan Quintela d32ca5ad79 multifd: Split multifd code into its own file
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela b673eab4e2 multifd: Make multifd_load_setup() get an Error parameter
We need to change the full chain to pass the Error parameter.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela 00f4b572e6 multifd: Make multifd_save_setup() get an Error parameter
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela 857a4bbb86 migration: Make checkpatch happy with comments
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela a6703e4d33 multifd: Use qemu_target_page_size()
We will make it cpu independent.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela 99f2c6fb46 multifd: multifd_send_sync_main only needs the qemufile
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela 67a4c8910c multifd: multifd_queue_page only needs the qemufile
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela df94d32bb1 multifd: multifd_send_pages only needs the qemufile
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Zhimin Feng 9c4d333c09 migration/multifd: fix nullptr access in multifd_send_terminate_threads
If the multifd_send_threads is not created when migration is failed,
multifd_save_cleanup would be called twice. In this senario, the
multifd_send_state is accessed after it has been released, the result
is that the source VM is crashing down.

Here is the coredump stack:
    Program received signal SIGSEGV, Segmentation fault.
    0x00005629333a78ef in multifd_send_terminate_threads (err=err@entry=0x0) at migration/ram.c:1012
    1012            MultiFDSendParams *p = &multifd_send_state->params[i];
    #0  0x00005629333a78ef in multifd_send_terminate_threads (err=err@entry=0x0) at migration/ram.c:1012
    #1  0x00005629333ab8a9 in multifd_save_cleanup () at migration/ram.c:1028
    #2  0x00005629333abaea in multifd_new_send_channel_async (task=0x562935450e70, opaque=<optimized out>) at migration/ram.c:1202
    #3  0x000056293373a562 in qio_task_complete (task=task@entry=0x562935450e70) at io/task.c:196
    #4  0x000056293373a6e0 in qio_task_thread_result (opaque=0x562935450e70) at io/task.c:111
    #5  0x00007f475d4d75a7 in g_idle_dispatch () from /usr/lib64/libglib-2.0.so.0
    #6  0x00007f475d4da9a9 in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
    #7  0x0000562933785b33 in glib_pollfds_poll () at util/main-loop.c:219
    #8  os_host_main_loop_wait (timeout=<optimized out>) at util/main-loop.c:242
    #9  main_loop_wait (nonblocking=nonblocking@entry=0) at util/main-loop.c:518
    #10 0x00005629334c5acf in main_loop () at vl.c:1810
    #11 0x000056293334d7bb in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4471

If the multifd_send_threads is not created when migration is failed.
In this senario, we don't call multifd_save_cleanup in multifd_new_send_channel_async.

Signed-off-by: Zhimin Feng <fengzhimin1@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela b69a0227a8 migration: Don't send data if we have stopped
If we do a cancel, we got out without one error, but we can't do the
rest of the output as in a normal situation.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela 3d4095b222 multifd: Make sure that we don't do any IO after an error
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-29 11:28:59 +01:00
Juan Quintela ddac5cb2d9 multifd: Be consistent about using uint64_t
We transmit ram_addr_t always as uint64_t.  Be consistent in its
use (on 64bit system, it is always uint64_t problem is 32bits).

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2020-01-20 09:17:07 +01:00
Alexey Romko 8bba004cca Bug #1829242 correction.
Added type conversions to ram_addr_t before all left shifts of page
indexes to TARGET_PAGE_BITS, to correct overflows when the page
address was 4Gb and more.

Signed-off-by: Alexey Romko <nevilad@yahoo.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Jiahui Cen 9560a48ecc migration/multifd: fix destroyed mutex access in terminating multifd threads
One multifd will lock all the other multifds' IOChannel mutex to inform them
to quit by setting p->quit or shutting down p->c. In this senario, if some
multifds had already been terminated and multifd_load_cleanup/multifd_save_cleanup
had destroyed their mutex, it could cause destroyed mutex access when trying
lock their mutex.

Here is the coredump stack:
    #0  0x00007f81a2794437 in raise () from /usr/lib64/libc.so.6
    #1  0x00007f81a2795b28 in abort () from /usr/lib64/libc.so.6
    #2  0x00007f81a278d1b6 in __assert_fail_base () from /usr/lib64/libc.so.6
    #3  0x00007f81a278d262 in __assert_fail () from /usr/lib64/libc.so.6
    #4  0x000055eb1bfadbd3 in qemu_mutex_lock_impl (mutex=0x55eb1e2d1988, file=<optimized out>, line=<optimized out>) at util/qemu-thread-posix.c:64
    #5  0x000055eb1bb4564a in multifd_send_terminate_threads (err=<optimized out>) at migration/ram.c:1015
    #6  0x000055eb1bb4bb7f in multifd_send_thread (opaque=0x55eb1e2d19f8) at migration/ram.c:1171
    #7  0x000055eb1bfad628 in qemu_thread_start (args=0x55eb1e170450) at util/qemu-thread-posix.c:502
    #8  0x00007f81a2b36df5 in start_thread () from /usr/lib64/libpthread.so.0
    #9  0x00007f81a286048d in clone () from /usr/lib64/libc.so.6

To fix it up, let's destroy the mutex after all the other multifd threads had
been terminated.

Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
Signed-off-by: Ying Fang <fangying1@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Jiahui Cen f76e32eb05 migration/multifd: fix nullptr access in terminating multifd threads
One multifd channel will shutdown all the other multifd's IOChannel when it
fails to receive an IOChannel. In this senario, if some multifds had not
received its IOChannel yet, it would try to shutdown its IOChannel which could
cause nullptr access at qio_channel_shutdown.

Here is the coredump stack:
    #0  object_get_class (obj=obj@entry=0x0) at qom/object.c:908
    #1  0x00005563fdbb8f4a in qio_channel_shutdown (ioc=0x0, how=QIO_CHANNEL_SHUTDOWN_BOTH, errp=0x0) at io/channel.c:355
    #2  0x00005563fd7b4c5f in multifd_recv_terminate_threads (err=<optimized out>) at migration/ram.c:1280
    #3  0x00005563fd7bc019 in multifd_recv_new_channel (ioc=ioc@entry=0x556400255610, errp=errp@entry=0x7ffec07dce00) at migration/ram.c:1478
    #4  0x00005563fda82177 in migration_ioc_process_incoming (ioc=ioc@entry=0x556400255610, errp=errp@entry=0x7ffec07dce30) at migration/migration.c:605
    #5  0x00005563fda8567d in migration_channel_process_incoming (ioc=0x556400255610) at migration/channel.c:44
    #6  0x00005563fda83ee0 in socket_accept_incoming_migration (listener=0x5563fff6b920, cioc=0x556400255610, opaque=<optimized out>) at migration/socket.c:166
    #7  0x00005563fdbc25cd in qio_net_listener_channel_func (ioc=<optimized out>, condition=<optimized out>, opaque=<optimized out>) at io/net-listener.c:54
    #8  0x00007f895b6fe9a9 in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
    #9  0x00005563fdc18136 in glib_pollfds_poll () at util/main-loop.c:218
    #10 0x00005563fdc181b5 in os_host_main_loop_wait (timeout=1000000000) at util/main-loop.c:241
    #11 0x00005563fdc183a2 in main_loop_wait (nonblocking=nonblocking@entry=0) at util/main-loop.c:517
    #12 0x00005563fd8edb37 in main_loop () at vl.c:1791
    #13 0x00005563fd74fd45 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at vl.c:4473

To fix it up, let's check p->c before calling qio_channel_shutdown.

Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
Signed-off-by: Ying Fang <fangying1@huawei.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang c6b3a2e0c4 migration/multifd: not use multifd during postcopy
We don't support multifd during postcopy, but user still could enable
both multifd and postcopy. This leads to migration failure.

Skip multifd during postcopy.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang eab54aa78f migration/multifd: clean pages after filling packet
This is a preparation for the next patch:

    not use multifd during postcopy.

Without enabling postcopy, everything looks good. While after enabling
postcopy, migration may fail even not use multifd during postcopy. The
reason is the pages is not properly cleared and *old* target page will
continue to be transferred.

After clean pages, migration succeeds.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang 644acf99b8 migration/postcopy: enable compress during postcopy
postcopy requires to place a whole host page, while migration thread
migrate memory in target page size. This makes postcopy need to collect
all target pages in one host page before placing via userfaultfd.

To enable compress during postcopy, there are two problems to solve:

    1. Random order for target page arrival
    2. Target pages in one host page arrives without interrupt by target
       page from other host page

The first one is handled by previous cleanup patch.

This patch handles the second one by:

    1. Flush compress thread for each host page
    2. Wait for decompress thread for before placing host page

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang 91ba442f5c migration/postcopy: enable random order target page arrival
After using number of target page received to track one host page, we
could have the capability to handle random order target page arrival in
one host page.

This is a preparation for enabling compress during postcopy.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang e5e73b0f90 migration/postcopy: set all_zero to true on the first target page
For the first target page, all_zero is set to true for this round check.

After target_pages introduced, we could leverage this variable instead
of checking the address offset.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang 4cbb3c63c1 migration/postcopy: count target page number to decide the place_needed
In postcopy, it requires to place whole host page instead of target
page.

Currently, it relies on the page offset to decide whether this is the
last target page. We also can count the target page number during the
iteration. When the number of target page equals
(host page size / target page size), this means it is the last target
page in the host page.

This is a preparation for non-ordered target page transmission.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang ca1a6b708b migration/postcopy: wait for decompress thread in precopy
Compress is not supported with postcopy, it is safe to wait for
decompress thread just in precopy.

This is a preparation for later patch.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Wei Yang 2e36bc1b88 migration/postcopy: reduce memset when it is zero page and matches_target_page_size
In this case, page_buffer content would not be used.

Skip this to save some time.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:23 +01:00
Yury Kotov e65cec5e5d migration/ram: Yield periodically to the main loop
Usually, incoming migration coroutine yields to the main loop
while its IO-channel is waiting for data to receive. But there is a case
when RAM migration and data receive have the same speed: VM with huge
zeroed RAM. In this case, IO-channel won't read and thus the main loop
is stuck and for instance, it doesn't respond to QMP commands.

For this case, yield periodically, but not too often, so as not to
affect the speed of migration.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:22 +01:00
Dr. David Alan Gilbert 97e1e06780 migration: Rate limit inside host pages
When using hugepages, rate limiting is necessary within each huge
page, since a 1G huge page can take a significant time to send, so
you end up with bursty behaviour.

Fixes: 4c011c37ec ("postcopy: Send whole huge pages")
Reported-by: Lin Ma <LMa@suse.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:22 +01:00
Daniel Henrique Barboza 03acb4e94d ram.c: remove unneeded labels
ram_save_queue_pages() has an 'err' label that can be replaced by
'return -1' instead.

Same thing with ram_discard_range(), and in this case we can also
get rid of the 'ret' variable and return either '-1' on error
or the result of ram_block_discard_range().

CC: Juan Quintela <quintela@redhat.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:22 +01:00
Juan Quintela 4d65a6216b migration: Make sure that we don't call write() in case of error
If we are exiting due to an error/finish/.... Just don't try to even
touch the channel with one IO operation.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2020-01-20 09:10:22 +01:00
Juan Quintela d069bcca6c multifd: Initialize local variable
Fill everything with zero, so the padding fields are also initialized.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-20 09:08:53 +01:00
Paolo Bonzini 44901b5aff colo: fix return without releasing RCU
Use WITH_RCU_READ_LOCK_GUARD to avoid exiting colo_init_ram_cache
without releasing RCU.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-17 19:33:52 +01:00
Marc-André Lureau e4f1bea2a8 migration: fix maybe-uninitialized warning
../migration/ram.c: In function ‘multifd_recv_thread’:
/home/elmarco/src/qq/include/qapi/error.h:165:5: error: ‘block’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  165 |     error_setg_internal((errp), __FILE__, __LINE__, __func__,   \
      |     ^~~~~~~~~~~~~~~~~~~
../migration/ram.c:818:15: note: ‘block’ was declared here
  818 |     RAMBlock *block;
      |               ^~~~~

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-17 19:32:47 +01:00
Beata Michalska bd108a44bc migration: ram: Switch to ram block writeback
Switch to ram block writeback for pmem migration.

Signed-off-by: Beata Michalska <beata.michalska@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20191121000843.24844-4-beata.michalska@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-12-16 10:46:35 +00:00
Wei Yang aff66d2ef0 migration/multifd: pages->used would be cleared when attach to multifd_send_state
When we found an available channel in multifd_send_pages(), its
pages->used is cleared and then attached to multifd_send_state.

It is not necessary to do this twice.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191011085050.17622-5-richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 15:02:06 +01:00
Wei Yang 9985e1f48d migration/multifd: initialize packet->magic/version once at setup stage
MultiFDPacket_t's magic and version field never changes during
migration, so move these two fields in setup stage.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191011085050.17622-4-richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 15:02:00 +01:00
Wei Yang f2148c4c79 migration/multifd: use pages->allocated instead of the static max
multifd_send_fill_packet() prepares meta data for following pages to
transfer. It would be more proper to fill pages->allocated instead of
static max value, especially we want to support flexible packet size.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191011085050.17622-3-richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 15:01:54 +01:00
Wei Yang d884e77bfe migration/multifd: fix a typo in comment of multifd_recv_unfill_packet()
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20191011085050.17622-2-richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 15:01:44 +01:00
Wei Yang 3414322a83 migration/postcopy: allocate tmp_page in setup stage
During migration, a tmp page is allocated so that we could place a whole
host page during postcopy.

Currently the page is allocated during load stage, this is a little bit
late. And more important, if we failed to allocate it, the error is not
checked properly. Even it is NULL, we would still use it.

This patch moves the allocation to setup stage and if failed error
message would be printed and caller would notice it.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:28:19 +01:00
Dr. David Alan Gilbert 89ac5a1d2a migration: Use automatic rcu_read unlock in ram.c
Use the automatic read unlocker in migration/ram.c

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20191007143642.301445-4-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:20:00 +01:00
Dr. David Alan Gilbert 0e6ebd4877 migration: Fix missing rcu_read_unlock
Use the automatic rcu_read unlocker to fix a missing unlock.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20191007143642.301445-3-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-10-11 14:19:59 +01:00
Wei Yang 64737606e8 migration: remove sent parameter in get_queued_page_not_dirty
This is a cleanup for previous removal of unsentmap.

The sent parameter is not necessary now.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190819061843.28642-4-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-09-25 15:51:19 +01:00
Wei Yang 1e7cf8c323 migration/postcopy: unsentmap is not necessary for postcopy
Commit f3f491fcd6 ('Postcopy: Maintain unsentmap') introduced
unsentmap to track not yet sent pages.

This is not necessary since:

    * unsentmap is a sub-set of bmap before postcopy start
    * unsentmap is the summation of bmap and unsentmap after canonicalizing

This patch just removes it.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190819061843.28642-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-09-25 15:51:19 +01:00
Wei Yang 8324ef86f0 migration/postcopy: not necessary to do discard when canonicalizing bitmap
All pages, either partially sent or partially dirty, will be discarded in
postcopy_send_discard_bm_ram(), since we update the unsentmap to be
unsentmap = unsentmap | dirty in ram_postcopy_send_discard_bitmap().

This is not necessary to do discard when canonicalizing bitmap. And by
doing so, we separate the page discard into two individual steps:

  * canonicalize bitmap
  * discard page

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190819061843.28642-2-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-09-25 15:51:19 +01:00
Dr. David Alan Gilbert ce62df5378 migration: register_savevm_live doesn't need dev
Commit 78dd48df3 removed the last caller of register_savevm_live for an
instantiable device (rather than a single system wide device);
so trim out the parameter.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190822115433.12070-1-dgilbert@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-09-12 11:15:03 +01:00
Ivan Ren 2f4aefd320 migration: multifd_send_thread always post p->sem_sync when error happen
When encounter error, multifd_send_thread should always notify who pay
attention to it before exit. Otherwise it may block migration_thread
at multifd_send_sync_main forever.

Error as follow:
-------------------------------------------------------------------------------
 (gdb) bt
 #0  0x00007f4d669dfa0b in do_futex_wait.constprop.1 () from /lib64/libpthread.so.0
 #1  0x00007f4d669dfa9f in __new_sem_wait_slow.constprop.0 () from /lib64/libpthread.so.0
 #2  0x00007f4d669dfb3b in sem_wait@@GLIBC_2.2.5 () from /lib64/libpthread.so.0
 #3  0x0000562ccf0a5614 in qemu_sem_wait (sem=sem@entry=0x562cd1b698e8) at util/qemu-thread-posix.c:319
 #4  0x0000562ccecb4752 in multifd_send_sync_main (rs=<optimized out>) at /qemu/migration/ram.c:1099
 #5  0x0000562ccecb95f4 in ram_save_iterate (f=0x562cd0ecc000, opaque=<optimized out>) at /qemu/migration/ram.c:3550
 #6  0x0000562ccef43c23 in qemu_savevm_state_iterate (f=0x562cd0ecc000, postcopy=false) at migration/savevm.c:1189
 #7  0x0000562ccef3dcf3 in migration_iteration_run (s=0x562cd09fabf0) at migration/migration.c:3131
 #8  migration_thread (opaque=opaque@entry=0x562cd09fabf0) at migration/migration.c:3258
 #9  0x0000562ccf0a4c26 in qemu_thread_start (args=<optimized out>) at util/qemu-thread-posix.c:502
 #10 0x00007f4d669d9e25 in start_thread () from /lib64/libpthread.so.0
 #11 0x00007f4d6670635d in clone () from /lib64/libc.so.6
 (gdb) f 4
 #4  0x0000562ccecb4752 in multifd_send_sync_main (rs=<optimized out>) at /qemu/migration/ram.c:1099
 1099	        qemu_sem_wait(&p->sem_sync);
 (gdb) list
 1094	    }
 1095	    for (i = 0; i < migrate_multifd_channels(); i++) {
 1096	        MultiFDSendParams *p = &multifd_send_state->params[i];
 1097
 1098	        trace_multifd_send_sync_main_wait(p->id);
 1099	        qemu_sem_wait(&p->sem_sync);
 1100	    }
 1101	    trace_multifd_send_sync_main(multifd_send_state->packet_num);
 1102	}
 1103
 (gdb) p i
 $1 = 0
 (gdb)  p multifd_send_state->params[0].pending_job
 $2 = 2    //It means the job before MULTIFD_FLAG_SYNC has already fail
 (gdb)  p multifd_send_state->params[0].quit
 $3 = true

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Message-Id: <1567044996-2362-1-git-send-email-ivanren@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-09-12 10:53:33 +01:00
Paolo Bonzini 9458a9a1df memory: fix race between TCG and accesses to dirty bitmap
There is a race between TCG and accesses to the dirty log:

      vCPU thread                  reader thread
      -----------------------      -----------------------
      TLB check -> slow path
        notdirty_mem_write
          write to RAM
          set dirty flag
                                   clear dirty flag
      TLB check -> fast path
                                   read memory
        write to RAM

Fortunately, in order to fix it, no change is required to the
vCPU thread.  However, the reader thread must delay the read after
the vCPU thread has finished the write.  This can be approximated
conservatively by run_on_cpu, which waits for the end of the current
translation block.

A similar technique is used by KVM, which has to do a synchronous TLB
flush after doing a test-and-clear of the dirty-page flags.

Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-20 17:26:20 +02:00
Juan Quintela 7dd59d01dd migration: add some multifd traces
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20190814020218.1868-6-quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Juan Quintela 18cdcea371 migration: Make global sem_sync semaphore by channel
This makes easy to debug things because when you want for all threads
to arrive at that semaphore, you know which one your are waiting for.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20190814020218.1868-3-quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Juan Quintela 5558c91ae8 migration: Add traces for multifd terminate threads
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20190814020218.1868-2-quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 7a3e957177 migration: rename migration_bitmap_sync_range to ramblock_sync_dirty_bitmap
Rename for better understanding of the code.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190808033155.30162-1-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Ivan Ren 81507f6b7e migration: update ram_counters for multifd sync packet
Multifd sync will send MULTIFD_FLAG_SYNC flag info to destination, add
these bytes to ram_counters record.

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Suggested-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <1564464816-21804-4-git-send-email-ivanren@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Ivan Ren 1b81c974cc migration: add speed limit for multifd migration
Limit the speed of multifd migration through common speed limitation
qemu file.

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Message-Id: <1564464816-21804-3-git-send-email-ivanren@tencent.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 9dec3cc3f4 migration/postcopy: use QEMU_IS_ALIGNED to replace host_offset
Use QEMU_IS_ALIGNED for the check, it would be more consistent with
other align calculations.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190806004648.8659-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang dad45ab2be migration/postcopy: simplify calculation of run_start and fixup_start_addr
The purpose of the calculation is to find a HostPage which is partially
dirty.

  * fixup_start_addr points to the start of the HostPage to discard
  * run_start points to the next HostPage to check

While in the middle stage, there would two cases for run_start:

  * aligned with HostPage means this is not partially dirty
  * not aligned means this is partially dirty

When it is aligned, no work and calculation is necessary. run_start
already points to the start of next HostPage and is ready to continue.

When it is not aligned, the calculation could be simplified with:

  * fixup_start_addr = QEMU_ALIGN_DOWN(run_start, host_ratio)
  * run_start = QEMU_ALIGN_UP(run_start, host_ratio)

By doing so, run_start always points to the next HostPage to check.
fixup_start_addr always points to the HostPage to discard.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190806004648.8659-2-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 810cf2bbd4 migration/postcopy: make PostcopyDiscardState a static variable
In postcopy-ram.c, we provide three functions to discard certain
RAMBlock range:

  * postcopy_discard_send_init()
  * postcopy_discard_send_range()
  * postcopy_discard_send_finish()

Currently, we allocate/deallocate PostcopyDiscardState for each RAMBlock
on sending discard information to destination. This is not necessary and
the same data area could be reused for each RAMBlock.

This patch defines PostcopyDiscardState a static variable. By doing so:

  1) avoid memory allocation and deallocation to the system
  2) avoid potential failure of memory allocation
  3) hide some details for their users

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>

Message-Id: <20190724010721.2146-1-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 10da4a3689 migration: extract ram_load_precopy
After cleanup, it would be clear to audience there are two cases
ram_load:

  * precopy
  * postcopy

And it is not necessary to check postcopy_running on each iteration for
precopy.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Message-Id: <20190725002023.2335-3-richardw.yang@linux.intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang be4a1a1b6f migration: return -EINVAL directly when version_id mismatch
It is not reasonable to continue when version_id mismatch.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190722075339.25121-2-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 5d0980a459 migration: just pass RAMBlock is enough
RAMBlock->used_length is always passed to migration_bitmap_sync_range(),
which could be retrieved from RAMBlock.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190718012547.16373-1-richardw.yang@linux.intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 8996604fe6 migration/postcopy: do_fixup is true when host_offset is non-zero
This means it is not necessary to spare an extra variable to hold this
condition. Use host_offset directly is fine.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190710050814.31344-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang e927a03317 migration/postcopy: reduce one operation to calculate fixup_start_addr
Use the same way for run_end to calculate run_start, which saves one
operation.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190710050814.31344-2-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang a162b572e9 migration/postcopy: discard_length must not be 0
Since we break the loop when there is no more page to discard, we are
sure the following process would find some page to discard.

It is not necessary to check it again.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190627020822.15485-4-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 33a5cb6202 migration/postcopy: break the loop when there is no more page to discard
When one is equal or bigger then end, it means there is no page to
discard. Just break the loop in this case instead of processing it.

No functional change, just refactor it a little.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190627020822.15485-3-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Wei Yang 0abfff9ea7 migration/postcopy: the valid condition is one less then end
If one equals end, it means we have gone through the whole bitmap.

Use a more restrict check to skip a unnecessary condition.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Message-Id: <20190627020822.15485-2-richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-08-14 17:33:14 +01:00
Ivan Ren f193bc0c53 migration: fix migrate_cancel multifd migration leads destination hung forever
When migrate_cancel a multifd migration, if run sequence like this:

        [source]                              [destination]

multifd_send_sync_main[finish]
                                    multifd_recv_thread wait &p->sem_sync
shutdown to_dst_file
                                    detect error from_src_file
send  RAM_SAVE_FLAG_EOS[fail]       [no chance to run multifd_recv_sync_main]
                                    multifd_load_cleanup
                                    join multifd receive thread forever

will lead destination qemu hung at following stack:

pthread_join
qemu_thread_join
multifd_load_cleanup
process_incoming_migration_co
coroutine_trampoline

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1561468699-9819-4-git-send-email-ivanren@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-24 14:47:21 +02:00
Juan Quintela 3c3ca25d1f migration: Make explicit that we are quitting multifd
We add a bool to indicate that.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-24 14:47:12 +02:00
Ivan Ren a3ec6b7d23 migration: fix migrate_cancel leads live_migration thread hung forever
When we 'migrate_cancel' a multifd migration, live_migration thread may
hung forever at some points, because of multifd_send_thread has already
exit for socket error:
1. multifd_send_pages may hung at qemu_sem_wait(&multifd_send_state->
   channels_ready)
2. multifd_send_sync_main my hung at qemu_sem_wait(&multifd_send_state->
   sem_sync)

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Message-Id: <1561468699-9819-3-git-send-email-ivanren@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

---

Remove spurious not needed bits
2019-07-24 14:47:02 +02:00
Ivan Ren 713f762a31 migration: fix migrate_cancel leads live_migration thread endless loop
When we 'migrate_cancel' a multifd migration, live_migration thread may
go into endless loop in multifd_send_pages functions.

Reproduce steps:

(qemu) migrate_set_capability multifd on
(qemu) migrate -d url
(qemu) [wait a while]
(qemu) migrate_cancel

Then may get live_migration 100% cpu usage in following stack:

pthread_mutex_lock
qemu_mutex_lock_impl
multifd_send_pages
multifd_queue_page
ram_save_multifd_page
ram_save_target_page
ram_save_host_page
ram_find_and_save_block
ram_find_and_save_block
ram_save_iterate
qemu_savevm_state_iterate
migration_iteration_run
migration_thread
qemu_thread_start
start_thread
clone

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Message-Id: <1561468699-9819-2-git-send-email-ivanren@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-24 14:46:51 +02:00
Ivan Ren 40c4d4a835 migration: always initial RAMBlock.bmap to 1 for new migration
Reproduce the problem:
migrate
migrate_cancel
migrate

Error happen for memory migration

The reason as follows:
1. qemu start, ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] all set to
   1 by a series of cpu_physical_memory_set_dirty_range
2. migration start:ram_init_bitmaps
   - memory_global_dirty_log_start: begin log diry
   - memory_global_dirty_log_sync: sync dirty bitmap to
     ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]
   - migration_bitmap_sync_range: sync ram_list.
     dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap
     and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero
3. migration data...
4. migrate_cancel, will stop log dirty
5. migration start:ram_init_bitmaps
   - memory_global_dirty_log_start: begin log diry
   - memory_global_dirty_log_sync: sync dirty bitmap to
     ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION]
   - migration_bitmap_sync_range: sync ram_list.
     dirty_memory[DIRTY_MEMORY_MIGRATION] to RAMBlock.bmap
     and ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] is set to zero

   Here RAMBlock.bmap only have new logged dirty pages, don't contain
   the whole guest pages.

Signed-off-by: Ivan Ren <ivanren@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1563115879-2715-1-git-send-email-ivanren@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-15 15:47:47 +02:00
Wei Yang 89dab31b27 migration/postcopy: fix document of postcopy_send_discard_bm_ram()
Commit 6b6712efcc ('ram: Split dirty bitmap by RAMBlock') changes the
parameter of postcopy_send_discard_bm_ram(), while left the document
part untouched.

This patch correct the document and fix two typo by hand.

Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190715020549.15018-1-richardw.yang@linux.intel.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-15 15:45:22 +02:00
Peng Tao b17fbbe55c migration: allow private destination ram with x-ignore-shared
By removing the share ram check, qemu is able to migrate
to private destination ram when x-ignore-shared capability
is on. Then we can create multiple destination VMs based
on the same source VM.

This changes the x-ignore-shared migration capability to
work similar to Lai's original bypass-shared-memory
work(https://lists.gnu.org/archive/html/qemu-devel/2018-04/msg00003.html)
which enables kata containers (https://katacontainers.io)
to implement the VM templating feature.

An example usage in kata containers(https://katacontainers.io):
1. Start the source VM:
   qemu-system-x86 -m 2G \
     -object memory-backend-file,id=mem0,size=2G,share=on,mem-path=/tmpfs/template-memory \
     -numa node,memdev=mem0
2. Stop the template VM, set migration x-ignore-shared capability,
   migrate "exec:cat>/tmpfs/state", quit it
3. Start target VM:
   qemu-system-x86 -m 2G \
     -object memory-backend-file,id=mem0,size=2G,share=off,mem-path=/tmpfs/template-memory \
     -numa node,memdev=mem0 \
     -incoming defer
4. connect to target VM qmp, set migration x-ignore-shared capability,
migrate_incoming "exec:cat /tmpfs/state"
5. create more target VMs repeating 3 and 4

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Yury Kotov <yury-kotov@yandex-team.ru>
Cc: Jiangshan Lai <laijs@hyper.sh>
Cc: Xu Wang <xu@hyper.sh>
Signed-off-by: Peng Tao <tao.peng@linux.alibaba.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1560494113-1141-1-git-send-email-tao.peng@linux.alibaba.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2019-07-15 15:39:03 +02:00