Function postcopy_ram_incoming_setup and postcopy_ram_incoming_cleanup
is a pair. Rename to make it clear for audience.
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20191010011316.31363-2-richardw.yang@linux.intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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>
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>
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>
Wire up a call to VHOST_USER_POSTCOPY_END message to the vhost clients
right before we ask the listener thread to shutdown.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add a hook to allow a client userfaultfd to be 'woken'
when a page arrives, and a walker that calls that
hook for relevant clients given a RAMBlock and offset.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Provide a helper to send a 'wake' request on a userfaultfd for
a shared process.
The address in the clients address space is specified together
with the RAMBlock it was resolved to.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Provide a helper to be used by shared waker functions to request
shared pages from the source.
The last_rb pointer is moved into the incoming state since this
helper can update it as well as the main fault thread function.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Notify the vhost-user slave on reception of the 'postcopy-listen'
event from the source.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Allow other userfaultfd's to be registered into the fault thread
so that handlers for shared memory can get responses.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Wire up a notifier to send a VHOST_USER_POSTCOPY_ADVISE
message on an incoming advise.
Later patches will fill in the behaviour/contents of the
message.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add a notifier chain for postcopy with a 'reason' flag
and an opportunity for a notifier member to return an error.
Call it when enabling postcopy.
This will initially used to enable devices to declare they're unable
to postcopy and later to notify of devices of stages within postcopy.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
A general helper to notify the fault thread.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-4-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Need to mark copied pages as closer as possible to the place where it
tracks down. That will be necessary in futher patch.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
That tiny refactoring is necessary to be able to set
UFFD_FEATURE_THREAD_ID while requesting features, and then
to create downtime context in case when kernel supports it.
Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Yes, we don't have a good place to put that stuff.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
It is internal to migration, not intended for other users.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Both the ram bitmap and the unsent bitmap are split by RAMBlock.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
--
Fix compilation when DEBUG_POSTCOPY is enabled (thanks Hailiang)
Now we deal with normal size pages and huge pages we need
to tell the place handlers the size we're dealing with
and make sure the temporary page is large enough.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-8-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Create ram_block_discard_range in exec.c to replace
postcopy_ram_discard_range and most of ram_discard_range.
Those two routines are a bit of a weird combination, and
ram_discard_range is about to get more complex for hugepages.
It's OS dependent code (so shouldn't be in migration/ram.c) but
it needs quite a bit of the innards of RAMBlock so doesn't belong in
the os*.c.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20170224182844.32452-5-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Prior to servicing userfault requests we must ensure we've not got
huge pages in the area that might include non-transferred memory,
since a hugepage could incorrectly mark the whole huge page as present.
We mark the area as non-huge page (nhp) just before we perform
discards; the discard code now tells us to discard any areas
that haven't been sent (as well as any that are redirtied);
any already formed transparent-huge-pages get fragmented
by this discard process if they cotnain any discards.
Transparent huge pages that have been entirely transferred
and don't contain any discards are not broken by this mechanism;
they stay as huge pages.
By starting postcopy after a full precopy pass, many of the pages
then stay as huge pages; this is important for maintaining performance
after the end of the migration.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
postcopy_place_page (etc) provide a way for postcopy to place a page
into guests memory atomically (using the copy ioctl on the ufd).
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Mark the area of RAM as 'userfault'
Start up a fault-thread to handle any userfaults we might receive
from it (to be filled in later)
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Soon we'll be in either ACTIVE or POSTCOPY_ACTIVE when we
complete migration, and we need to know which we expect to be
in to change state safely.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Provide a check to see if the OS we're running on has all the bits
needed for postcopy.
Creates postcopy-ram.c which will get most of the other helpers we need.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>