Commit Graph

276 Commits

Author SHA1 Message Date
Wei Wang 6eeb63f740 migration/ram.c: add the free page optimization enable flag
This patch adds the free page optimization enable flag, and a function
to set this flag. When the free page optimization is enabled, not all
the pages are needed to be sent in the bulk stage.

Why using a new flag, instead of directly disabling ram_bulk_stage when
the optimization is running?
Thanks for Peter Xu's reminder that disabling ram_bulk_stage will affect
the use of compression. Please see save_page_use_compression. When
xbzrle and compression are used, if free page optimizaion causes the
ram_bulk_stage to be disabled, save_page_use_compression will return
false, which disables the use of compression. That is, if free page
optimization avoids the sending of half of the guest pages, the other
half of pages loses the benefits of compression in the meantime. Using a
new flag to let migration_bitmap_find_dirty skip the free pages in the
bulk stage will avoid the above issue.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-7-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>
2019-03-06 10:49:18 +00:00
Wei Wang bd2270608f migration/ram.c: add a notifier chain for precopy
This patch adds a notifier chain for the memory precopy. This enables various
precopy optimizations to be invoked at specific places.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-6-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:18 +00:00
Wei Wang 6bcb05fc42 migration: API to clear bits of guest free pages from the dirty bitmap
This patch adds an API to clear bits corresponding to guest free pages
from the dirty bitmap. Spilt the free page block if it crosses the QEMU
RAMBlock boundary.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-5-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:18 +00:00
Wei Wang 386a907b37 migration: use bitmap_mutex in migration_bitmap_clear_dirty
The bitmap mutex is used to synchronize threads to update the dirty
bitmap and the migration_dirty_pages counter. For example, the free
page optimization clears bits of free pages from the bitmap in an
iothread context. This patch makes migration_bitmap_clear_dirty update
the bitmap and counter under the mutex.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-4-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:18 +00:00
Yury Kotov fbd162e629 migration: Add an ability to ignore shared RAM blocks
If ignore-shared capability is set then skip shared RAMBlocks during the
RAM migration.
Also, move qemu_ram_foreach_migratable_block (and rename) to the
migration code, because it requires access to the migration capabilities.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-4-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:17 +00:00
Xiao Guangrong aecbfe9c64 migration: introduce pages-per-second
It introduces a new statistic, pages-per-second, as bandwidth or mbps is
not enough to measure the performance of posting pages out as we have
compression, xbzrle, which can significantly reduce the amount of the
data size, instead, pages-per-second is the one we want

Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20190111063732.10484-2-xiaoguangrong@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  With typo's Eric spotted fixed
2019-01-23 15:51:47 +00:00
Fei Li 1398b2e3fe migration: multifd_save_cleanup() can't fail, simplify
multifd_save_cleanup() takes an Error ** argument and returns an
error code even though it can't actually fail.  Its callers
dutifully check for failure.  Remove the useless argument and return
value, and simplify the callers.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20190113140849.38339-4-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23 15:02:07 +00:00
Fei Li 49ed0d24a4 migration: fix the multifd code when receiving less channels
In our current code, when multifd is used during migration, if there
is an error before the destination receives all new channels, the
source keeps running, however the destination does not exit but keeps
waiting until the source is killed deliberately.

Fix this by dumping the specific error and let users decide whether
to quit from the destination side when failing to receive packet via
some channel. And update the comment for multifd_recv_new_channel().

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20190113140849.38339-3-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23 15:02:07 +00:00
Paolo Bonzini b58deb344d qemu/queue.h: leave head structs anonymous unless necessary
Most list head structs need not be given a name.  In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed.  In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct.  So clean up everything, not giving a
name except in the rare case where it is necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
zhanghailiang d1955d2219 COLO: flush host dirty ram from cache
Don't need to flush all VM's ram from cache, only
flush the dirty pages since last checkpoint

Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen e6f4aa188c COLO: Flush memory data from ram cache
During the time of VM's running, PVM may dirty some pages, we will transfer
PVM's dirty pages to SVM and store them into SVM's RAM cache at next checkpoint
time. So, the content of SVM's RAM cache will always be same with PVM's memory
after checkpoint.

Instead of flushing all content of PVM's RAM cache into SVM's MEMORY,
we do this in a more efficient way:
Only flush any page that dirtied by PVM since last checkpoint.
In this way, we can ensure SVM's memory same with PVM's.

Besides, we must ensure flush RAM cache before load device state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen 7d9acafa2c ram/COLO: Record the dirty pages that SVM received
We record the address of the dirty pages that received,
it will help flushing pages that cached into SVM.

Here, it is a trick, we record dirty pages by re-using migration
dirty bitmap. In the later patch, we will start the dirty log
for SVM, just like migration, in this way, we can record both
the dirty pages caused by PVM and SVM, we only flush those dirty
pages from RAM cache while do checkpoint.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen 13af18f222 COLO: Load dirty pages into SVM's RAM cache firstly
We should not load PVM's state directly into SVM, because there maybe some
errors happen when SVM is receving data, which will break SVM.

We need to ensure receving all data before load the state into SVM. We use
an extra memory to cache these data (PVM's ram). The ram cache in secondary side
is initially the same as SVM/PVM's memory. And in the process of checkpoint,
we cache the dirty pages of PVM into this ram cache firstly, so this ram cache
always the same as PVM's memory at every checkpoint, then we flush this cached ram
to SVM after we receive all PVM's state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Peter Maydell 341ba0df4c migration/ram.c: Avoid taking address of fields in packed MultiFDInit_t struct
Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this:

migration/ram.c:651:19: warning: taking address of packed member 'magic' of class or structure 'MultiFDInit_t' may result in an unaligned pointer value [-Waddress-of-packed-member]
migration/ram.c:652:19: warning: taking address of packed member 'version' of class or structure 'MultiFDInit_t' may result in an unaligned pointer value [-Waddress-of-packed-member]
migration/ram.c:737:19: warning: taking address of packed member 'magic' of class or structure 'MultiFDPacket_t' may result in an unaligned pointer value [-Waddress-of-packed-member]
migration/ram.c:745:19: warning: taking address of packed member 'version' of class or structure 'MultiFDPacket_t' may result in an unaligned pointer value [-Waddress-of-packed-member]
migration/ram.c:755:19: warning: taking address of packed member 'size' of class or structure 'MultiFDPacket_t' may result in an unaligned pointer value [-Waddress-of-packed-member]

Avoid the bug by not using the "modify in place" byteswapping
functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180925161924.7832-1-peter.maydell@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 17:29:01 +01:00
Fei Li 05306935b1 migration: fix the compression code
Add judgement in compress_threads_save_cleanup() to check whether the
static CompressParam *comp_param has been allocated. If not, just
return; or else segmentation fault will occur when using the NULL
comp_param's parameters.  One test case can reproduce this is: set
the compression on and migrate to a wrong nonexistent host IP address.

Our current code does not judge before handling comp_param[idx]'s quit
and cond that whether they have been initialized. If not initialized,
"qemu_mutex_lock_impl: Assertion `mutex->initialized' failed." will
occur. Fix this by squashing the terminate_compression_threads() into
compress_threads_save_cleanup() and employing the existing judgement
condition.  One test case can reproduce this error is: set the
compression on and fail to fully setup the default eight compression
thread in compress_threads_save_setup().

Signed-off-by: Fei Li <fli@suse.com>
Message-Id: <20180925091440.18910-1-fli@suse.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 17:29:01 +01:00
Xiao Guangrong 32b054954f migration: use save_page_use_compression in flush_compressed_data
It avoids to touch compression locks if xbzrle and compression
are both enabled

Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20180906070101.27280-4-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:27:43 +01:00
Xiao Guangrong 76e030004f migration: show the statistics of compression
Currently, it includes:
pages: amount of pages compressed and transferred to the target VM
busy: amount of count that no free thread to compress data
busy-rate: rate of thread busy
compressed-size: amount of bytes after compression
compression-rate: rate of compressed size

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180906070101.27280-3-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:27:27 +01:00
Xiao Guangrong 48df9d8002 migration: do not flush_compressed_data at the end of iteration
flush_compressed_data() needs to wait all compression threads to
finish their work, after that all threads are free until the
migration feeds new request to them, reducing its call can improve
the throughput and use CPU resource more effectively

We do not need to flush all threads at the end of iteration, the
data can be kept locally until the memory block is changed or
memory migration starts over in that case we will meet a dirtied
page which may still exists in compression threads's ring

Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20180906070101.27280-2-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:26:58 +01:00
Xiao Guangrong e8f3735fa3 migration: handle the error condition properly
ram_find_and_save_block() can return negative if any error hanppens,
however, it is completely ignored in current code

Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20180903092644.25812-5-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:22:21 +01:00
Xiao Guangrong be8b02edae migration: fix calculating xbzrle_counters.cache_miss_rate
As Peter pointed out:
| - xbzrle_counters.cache_miss is done in save_xbzrle_page(), so it's
|   per-guest-page granularity
|
| - RAMState.iterations is done for each ram_find_and_save_block(), so
|   it's per-host-page granularity
|
| An example is that when we migrate a 2M huge page in the guest, we
| will only increase the RAMState.iterations by 1 (since
| ram_find_and_save_block() will be called once), but we might increase
| xbzrle_counters.cache_miss for 2M/4K=512 times (we'll call
| save_xbzrle_page() that many times) if all the pages got cache miss.
| Then IMHO the cache miss rate will be 512/1=51200% (while it should
| actually be just 100% cache miss).

And he also suggested as xbzrle_counters.cache_miss_rate is the only
user of rs->iterations we can adapt it to count target guest page
numbers

After that, rename 'iterations' to 'target_page_count' to better reflect
its meaning

Suggested-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180903092644.25812-3-xiaoguangrong@tencent.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:21:56 +01:00
Peter Xu 3ab72385b2 qapi: Drop qapi_event_send_FOO()'s Error ** argument
The generated qapi_event_send_FOO() take an Error ** argument.  They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().

Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.

Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28 18:21:38 +02:00
Xiao Guangrong ae526e32bd migration: hold the lock only if it is really needed
Try to hold src_page_req_mutex only if the queue is not
empty

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:36:18 +02:00
Xiao Guangrong 5e5fdcff28 migration: move handle of zero page to the thread
Detecting zero page is not a light work, moving it to the thread to
speed the main thread up, btw, handling ram_release_pages() for the
zero page is moved to the thread as well

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:36:18 +02:00
Xiao Guangrong 6ef3771c0d migration: drop the return value of do_compress_ram_page
It is not used and cleans the code up a little

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:36:18 +02:00
Xiao Guangrong 6c97ec5f5a migration: introduce save_zero_page_to_file
It will be used by the compression threads

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:36:10 +02:00
Xiao Guangrong 980a19a929 migration: fix counting normal page for compression
The compressed page is not normal page

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:34:21 +02:00
Xiao Guangrong 1d58872a91 migration: do not wait for free thread
Instead of putting the main thread to sleep state to wait for
free compression thread, we can directly post it out as normal
page that reduces the latency and uses CPUs more efficiently

A parameter, compress-wait-thread, is introduced, it can be
enabled if the user really wants the old behavior

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:34:11 +02:00
Lidong Chen 74637e6f08 migration: implement bi-directional RDMA QIOChannel
This patch implements bi-directional RDMA QIOChannel. Because different
threads may access RDMAQIOChannel currently, this patch use RCU to protect it.

Signed-off-by: Lidong Chen <lidongchen@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>
2018-08-22 12:12:26 +02:00
Li Qiang 4cbc9c7ffd migrate/cpu-throttle: Add max-cpu-throttle migration parameter
Currently, the default maximum CPU throttle for migration is
99(CPU_THROTTLE_PCT_MAX). This is too big and can make a remarkable
performance effect for the guest. We see a lot of packets latency
exceed 500ms when the CPU_THROTTLE_PCT_MAX reached. This patch set
adds a new max-cpu-throttle parameter to limit the CPU throttle.

Signed-off-by: Li Qiang <liq3ea@gmail.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>
2018-08-22 11:42:34 +02:00
Junyan He 56eb90af39 migration/ram: ensure write persistence on loading all data to PMEM.
Because we need to make sure the pmem kind memory data is synced
after migration, we choose to call pmem_persist() when the migration
finish. This will make sure the data of pmem is safe and will not
lose if power is off.

Signed-off-by: Junyan He <junyan.he@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-10 13:29:39 +03:00
Junyan He 469dd51bc6 migration/ram: Add check and info message to nvdimm post copy.
The nvdimm kind memory does not support post copy now.
We disable post copy if we have nvdimm memory and print some
log hint to user.

Signed-off-by: Junyan He <junyan.he@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-10 13:29:39 +03:00
Peter Xu 814bb08f17 migration: update recv bitmap only on dest vm
We shouldn't update the received bitmap if we're the source VM.  This
fixes a breakage when release-ram is enabled on postcopy.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180723123305.24792-2-peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-24 17:10:41 +01:00
Peter Xu 4fcefd44a0 migration: fix potential overflow in multifd send
I would guess it won't happen normally, but this should ease Coverity.

>>>     CID 1394385:  Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
>>>     Potentially overflowing expression "pages->used * 8192U" with type "unsigned int" (32 bits, unsigned) is evaluated using 32-bit arithmetic, and then used in a context that expects an expression of type "uint64_t" (64 bits, unsigned).
854         transferred = pages->used * TARGET_PAGE_SIZE + p->packet_len;

Fixes: CID 1394385
CC: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180720034713.11711-1-peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-24 16:58:51 +01:00
Peter Xu a725ef9fe3 migration: fix incorrect bitmap size calculation
The calculation on size of received bitmap is incorrect for postcopy
recovery.  Here we wanted to let the size to cover all the valid bits in
the bitmap, we should use DIV_ROUND_UP() instead of a division.

For example, a RAMBlock with size=4K (which contains only one single 4K
page) will have nbits=1, then nbits/8=0, then the real bitmap won't be
sent to source at all.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180710091902.28780-4-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 12:56:18 +01:00
Peter Xu 1aa8367861 migration: simplify check to use qemu file buffer
Firstly, renaming the old matching_page_sizes variable to
matches_target_page_size, which suites more to what it did (it only
checks against target page size rather than multiple page sizes).
Meanwhile, simplify the check logic a bit, and enhance the comments.
Should have no functional change.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180710091902.28780-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 12:55:59 +01:00
Peter Xu 81e620531f migration: move income process out of multifd
Move the call to migration_incoming_process() out of multifd code.  It's
a bit strange that we can migration generic calls in multifd code.
Instead, let multifd_recv_new_channel() return a boolean showing whether
it's ready to continue the incoming migration.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180627132246.5576-3-peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 12:48:53 +01:00
David Hildenbrand c136180c90 postcopy: drop ram_pages parameter from postcopy_ram_incoming_init()
Not needed. Don't expose last_ram_page().

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180620202736.21399-1-david@redhat.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>
2018-06-27 13:28:31 +02:00
Juan Quintela 35374cbdff migration: Stop sending whole pages through main channel
We have to flush() the QEMUFile because now we sent really few data
through that channel.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:30 +02:00
Juan Quintela 7a5cc33c48 migration: Remove not needed semaphore and quit
We know quit with shutdwon in the QIO.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
--
Add comment
Use shutdown() instead of unref()
2018-06-27 13:28:21 +02:00
Juan Quintela 4d22c148c9 migration: Wait for blocking IO
We have three conditions here:
- channel fails -> error
- we have to quit: we close the channel and reads fails
- normal read that success, we are in bussiness

So forget the complications of waiting in a semaphore.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:11 +02:00
Juan Quintela 8b2db7f5fd migration: Start sending messages
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:11 +02:00
Juan Quintela b9ee2f7d70 migration: Create ram_save_multifd_page
The function still don't use multifd, but we have simplified
ram_save_page, xbzrle and RDMA stuff is gone.  We have added a new
counter.

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

--
Add last_page parameter
Add commets for done and address
Remove multifd field, it is the same than normal pages
Merge next patch, now we send multiple pages at a time
Remove counter for multifd pages, it is identical to normal pages
Use iovec's instead of creating the equivalent.
Clear memory used by pages (dave)
Use g_new0(danp)
define MULTIFD_CONTINUE
now pages member is a pointer
Fix off-by-one in number of pages in one packet
Remove RAM_SAVE_FLAG_MULTIFD_PAGE
s/multifd_pages_t/MultiFDPages_t/
add comment explaining what it means
2018-06-27 13:28:11 +02:00
Juan Quintela 6df264ac5a migration: Synchronize multifd threads with main thread
We synchronize all threads each RAM_SAVE_FLAG_EOS.  Bitmap
synchronizations don't happen inside a  ram section, so we are safe
about two channels trying to overwrite the same memory.

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

--
seq needs to be atomic now, will also be accessed from main thread.
Fix the if (true || ...) leftover
We are back to non-atomics
2018-06-27 13:28:11 +02:00
Juan Quintela 0beb5ed327 migration: Add block where to send/receive packets
Once there add tracepoints.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:11 +02:00
Juan Quintela d82628e4bd migration: Multifd channels always wait on the sem
Either for quit, sync or packet, we first wake them.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:11 +02:00
Juan Quintela 408ea6ae4c migration: Add multifd traces for start/end thread
We want to know how many pages/packets each channel has sent.  Add
counters for those.

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

--
sort trace-events (dave)
2018-06-27 13:28:11 +02:00
Juan Quintela 2a26c979b1 migration: Create multifd packet
We still don't put anything there.

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

--
fix magic (dave)
check offset/ramblock  (dave)
s/seq/packet_num/ and make it 64bit
2018-06-27 13:28:11 +02:00
Juan Quintela 34c55a94b1 migration: Create multipage support
We only create/destry the page list here.  We will use it later.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-27 13:28:11 +02:00
Balamuruhan S 650af8907b migration: calculate expected_downtime with ram_bytes_remaining()
expected_downtime value is not accurate with dirty_pages_rate * page_size,
using ram_bytes_remaining() would yeild it resonable.

consider to read the remaining ram just after having updated the dirty
pages count later migration_bitmap_sync_range() in migration_bitmap_sync()
and reuse the `remaining` field in ram_counters to hold ram_bytes_remaining()
for calculating expected_downtime.

Reported-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20180612085009.17594-2-bala24@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-15 14:40:56 +01:00
Dr. David Alan Gilbert e03a34f8f3 migration/postcopy: Wake rate limit sleep on postcopy request
Use the 'urgent request' mechanism added in the previous patch
for entries added to the postcopy request queue for RAM.  Ignore
the rate limiting while we have requests.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180613102642.23995-4-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-06-15 14:40:56 +01:00