* Michael S. Tsirkin (m...@redhat.com) wrote:
> On Fri, Feb 16, 2018 at 01:15:56PM +0000, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
> >
> > Hi,
> > This is the first non-RFC version of this patch set that
> > enables postcopy migration with shared memory to a vhost user process.
> > It's based off current head.
> >
> > I've tested with vhost-user-bridge and a modified dpdk; both very
> > lightly.
> >
> > Compared to v2 we're now using the just-merged reworks to the vhost
> > code (suggested by Igor), so that the huge page region merging is now a lot
> > simpler
> > in this series. The handshake between the client and the qemu for the
> > set-mem-table is now a bit more complex to resolve a previous race where
> > the client would start sending requests to the qemu prior to the qemu
> > being ready to accept them.
> >
> > Dave
>
> From vhost-user POV this seems mostly fine to me.
OK, great - it would be nice to get this merged in the upcoming release
(Hint: Anyone else please review!)
> I would like to have dependency of specific messages on the
> protocol features documented, and the order of messages
> documented a bit more explicitly.
Something like the following? (appropriately merged in with the
individual commits):
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
index 4bf7d8ef99..7841812766 100644
--- a/docs/interop/vhost-user.txt
+++ b/docs/interop/vhost-user.txt
@@ -461,7 +461,7 @@ Master message types
for each memory mapped region. The size and ordering of the fds matches
the number and ordering of memory regions.
- When postcopy-listening has been received, SET_MEM_TABLE replies with
+ When VHOST_USER_POSTCOPY_LISTEN has been received, SET_MEM_TABLE replies
with
the bases of the memory mapped regions to the master. It must have
mmap'd
the regions but not yet accessed them and should not yet generate a
userfault
event. Note NEED_REPLY_MASK is not set in this case.
@@ -687,7 +687,8 @@ Master message types
Master payload: N/A
Slave payload: userfault fd + u64
- Master advises slave that a migration with postcopy enabled is underway,
+ When VHOST_USER_PROTOCOL_F_PAGEFAULT is supported, the
+ master advises slave that a migration with postcopy enabled is underway,
the slave must open a userfaultfd for later use.
Note that at this stage the migration is still in precopy mode.
@@ -696,6 +697,8 @@ Master message types
Master payload: N/A
Master advises slave that a transition to postcopy mode has happened.
+ This is always sent sometime after a VHOST_USER_POSTCOPY_ADVISE, and
+ thus only when VHOST_USER_PROTOCOL_F_PAGEFAULT is supported.
* VHOST_USER_POSTCOPY_END
Id: 28
@@ -704,6 +707,8 @@ Master message types
Master advises that postcopy migration has now completed. The
slave must disable the userfaultfd. The response is an acknowledgement
only.
+ This message is sent at the end of the migration, after
+ VHOST_USER_POSTCOPY_LISTEN was previously sent.
Slave message types
-------------------
Dave
>
>
>
> > Dr. David Alan Gilbert (29):
> > migrate: Update ram_block_discard_range for shared
> > qemu_ram_block_host_offset
> > postcopy: use UFFDIO_ZEROPAGE only when available
> > postcopy: Add notifier chain
> > postcopy: Add vhost-user flag for postcopy and check it
> > vhost-user: Add 'VHOST_USER_POSTCOPY_ADVISE' message
> > libvhost-user: Support sending fds back to qemu
> > libvhost-user: Open userfaultfd
> > postcopy: Allow registering of fd handler
> > vhost+postcopy: Register shared ufd with postcopy
> > vhost+postcopy: Transmit 'listen' to client
> > postcopy+vhost-user: Split set_mem_table for postcopy
> > migration/ram: ramblock_recv_bitmap_test_byte_offset
> > libvhost-user+postcopy: Register new regions with the ufd
> > vhost+postcopy: Send address back to qemu
> > vhost+postcopy: Stash RAMBlock and offset
> > vhost+postcopy: Send requests to source for shared pages
> > vhost+postcopy: Resolve client address
> > postcopy: wake shared
> > postcopy: postcopy_notify_shared_wake
> > vhost+postcopy: Add vhost waker
> > vhost+postcopy: Call wakeups
> > libvhost-user: mprotect & madvises for postcopy
> > vhost-user: Add VHOST_USER_POSTCOPY_END message
> > vhost+postcopy: Wire up POSTCOPY_END notify
> > vhost: Huge page align and merge
> > postcopy: Allow shared memory
> > libvhost-user: Claim support for postcopy
> > postcopy shared docs
> >
> > contrib/libvhost-user/libvhost-user.c | 303 ++++++++++++++++++++++++-
> > contrib/libvhost-user/libvhost-user.h | 8 +
> > docs/devel/migration.rst | 41 ++++
> > docs/interop/vhost-user.txt | 42 ++++
> > exec.c | 85 +++++--
> > hw/virtio/trace-events | 16 +-
> > hw/virtio/vhost-user.c | 411
> > +++++++++++++++++++++++++++++++++-
> > hw/virtio/vhost.c | 66 +++++-
> > include/exec/cpu-common.h | 4 +
> > migration/migration.c | 6 +
> > migration/migration.h | 4 +
> > migration/postcopy-ram.c | 350 +++++++++++++++++++++++------
> > migration/postcopy-ram.h | 69 ++++++
> > migration/ram.c | 5 +
> > migration/ram.h | 1 +
> > migration/savevm.c | 13 ++
> > migration/trace-events | 6 +
> > trace-events | 3 +-
> > vl.c | 2 +
> > 19 files changed, 1337 insertions(+), 98 deletions(-)
> >
> > --
> > 2.14.3
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
