Instead of testing each page individually, we search what is the next
dirty page with a bitmap operation. We have to reorganize the code to
move from a "for" loop, to a while(dirty) loop.
Signed-off-by: Juan Quintela <quintela@redhat.com>
This avoids having to do two walks over the dirty bitmap, once reading
the dirty bits, and anthoer cleaning them.
Signed-off-by: Juan Quintela <quintela@redhat.com>
This is the last block from where we have sent data.
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Code just now does (simplified for clarity)
if (qemu_savevm_state_iterate(s->file) == 1) {
vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
qemu_savevm_state_complete(s->file);
}
Problem here is that qemu_savevm_state_iterate() returns 1 when it
knows that remaining memory to sent takes less than max downtime.
But this means that we could end spending 2x max_downtime, one
downtime in qemu_savevm_iterate, and the other in
qemu_savevm_state_complete.
Changed code to:
pending_size = qemu_savevm_state_pending(s->file, max_size);
DPRINTF("pending size %lu max %lu\n", pending_size, max_size);
if (pending_size >= max_size) {
ret = qemu_savevm_state_iterate(s->file);
} else {
vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
qemu_savevm_state_complete(s->file);
}
So what we do is: at current network speed, we calculate the maximum
number of bytes we can sent: max_size.
Then we ask every save_live section how much they have pending. If
they are less than max_size, we move to complete phase, otherwise we
do an iterate one.
This makes things much simpler, because now individual sections don't
have to caluclate the bandwidth (it was implossible to do right from
there).
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Add the new mutex that protects shared state between ram_save_live
and the iothread. If the iothread mutex has to be taken together
with the ramlist mutex, the iothread shall always be _outside_.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Umesh Deshpande <udeshpan@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
This will be used to detect if last_block might have become invalid
across different calls to ram_save_live.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Umesh Deshpande <udeshpan@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Most of the time, only 2 items will be active (from/to for a string operation,
or code/data). But TCG guests likely won't have gigabytes of memory, so
this actually goes down to 1 item.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Various header files rely on qemu-char.h including qemu-config.h or
main-loop.h, but they really do not need qemu-char.h at all (particularly
interesting is the case of the block layer!). Clean this up, and also
add missing inclusions of qemu-char.h itself.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
madvise(DONTNEED) will throw away the contents of the whole page at the
given address, even if the given length is less than the page size. One
can argue about whether that's the correct behaviour, but that's what it's
done for a long time in Linux at least.
That means that the madvise() in ram_load(), on a setup where
TARGET_PAGE_SIZE is smaller than the host page size, can throw away data
in guest pages adjacent to the one it's actually processing right now,
leading to guest memory corruption on an incoming migration.
This patch therefore, disables the madvise() if the host page size is
larger than TARGET_PAGE_SIZE. This means we don't get the benefits of that
madvise() in this case, but a more complete fix is more difficult to
accomplish. This at least fixes the guest memory corruption.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The code for migrating (or savevm-ing) memory pages starts off by creating
a dirty bitmap and filling it with 1s. Except, actually, because bit
addresses are 0-based it fills every bit except bit 0 with 1s and puts an
extra 1 beyond the end of the bitmap, potentially corrupting unrelated
memory. Oops. This patch fixes it.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch creates a migration bitmap, which is periodically kept in
sync with the qemu bitmap. A separate copy of the dirty bitmap for the
migration limits the amount of concurrent access to the qemu bitmap
from iothread and migration thread (which requires taking the big
lock).
We use the qemu bitmap type. We have to "undo" the dirty_pages
counting optimization on the general dirty bitmap and do the counting
optimization with the migration local bitmap.
Signed-off-by: Umesh Deshpande <udeshpan@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Helper that we use each time that we need to syncronize the migration
bitmap with the other dirty bitmaps.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
It just test if the dirty bit is set, and clears it.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
It just marks a region of memory as dirty.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
This file is not needed anymore, as QEMU won't ship any config-based
cpudefs out of the box, relying only on the builtin CPU models.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
For architectures which don't set HAS_AUDIO_CHOICE, improve the
'-soundhw help' message so that it doesn't simply print an empty
list, implying no sound support at all.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: malc <av1474@comtv.ru>
'%' symbols were missing in front of PRIu64 macros in DPRINTF() messages in
arch_init.c, this caused compilation warnings when compiled with DEBUG_ARCH_INIT defined.
Signed-off-by: Igor Mitsyanko <i.mitsyanko@samsung.com>
Signed-off-by: Stefan Hajnoczi <stefanha@gmail.com>
Add a 'query-target' QAPI command to allow management applications
to determine what target architecture a QEMU binary is emulating
without having to parse the binary name or -help output
$ qmp-shell -p /tmp/qemu
(QEMU) query-target
{ u'return': { u'arch': u'x86_64' }}
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch adds unicore32-softmmu build support, include configure,
makefile, arch_init, and all missing functions needed by softmmu.
Although all missing functions are empty, unicore32-softmmu could
be build successfully.
By 20120804: change QEMU_ARCH_UNICORE32 to 0x4000
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Change XBZRLE cache size in bytes (the size should be a power of 2, it will be
rounded down to the nearest power of 2).
If XBZRLE cache size is too small there will be many cache miss.
New query-migrate-cache-size QMP command and 'info migrate_cache_size' HMP
command to query cache value.
Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
Signed-off-by: Petter Svard <petters@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
In the outgoing migration check to see if the page is cached and
changed, then send compressed page by using save_xbrle_page function.
In the incoming migration check to see if RAM_SAVE_FLAG_XBZRLE is set
and decompress the page (by using load_xbrle function).
Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
Signed-off-by: Petter Svard <petters@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
For command line options which permit '?' meaning 'please list the
permitted values', add support for 'help' as a synonym, by abstracting
the check out into a helper function.
This change means that in some cases where we were being lazy in
our string parsing, "?junk" will now be rejected as an invalid option
rather than being (undocumentedly) treated the same way as "?".
Update the documentation to use 'help' rather than '?', since '?'
is a shell metacharacter and thus prone to fail confusingly if there
is a single character filename in the current working directory and
the '?' has not been escaped. It's therefore better to steer users
towards 'help', though '?' is retained for backwards compatibility.
We do not, however, update the output of the system emulator's -help
(or any documentation autogenerated from the qemu-options.hx which
is the source of the -help text) because libvirt parses our -help
output and will break. At a later date when QEMU provides a better
interface so libvirt can avoid having to do this, we can update the
-help text too.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
* commit '6c779f22a93cc6e4565b940ef616e3efc5b50ba5':
Change ram_save_block to return -1 if there are no more changes
ram: save_live_setup() we don't need to synchronize the dirty bitmap.
ram: iterate phase
ram: save_live_complete() only do one loop
ram: save_live_setup() don't need to sent pages
savevm: split save_live into stage2 and stage3
savevm: split save_live_setup from save_live_state
savevm: introduce is_active method
savevm: Refactor cancel operation in its own operation
savevm: remove SaveLiveStateHandler
savevm: remove SaveSetParamsHandler
savevm: Live migration handlers register the struct directly
savevm: Use a struct to pass all handlers
1st: we were synchonizing the dirty bitmap before calling
memory_global_dirty_log_start().
2nd: We are marking all pages as dirty anywhere, no reason to go
through all the bitmap to "mark" dirty same pages twice.
So, call removed.
Signed-off-by: Juan Quintela <quintela@redhat.com>
We only need to synchronize the bitmap when the number of dirty pages is low.
Not every time that we call the function.
Signed-off-by: Juan Quintela <quintela@redhat.com>
