Commit Graph

369 Commits

Author SHA1 Message Date
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