On Tue, Feb 27, 2018 at 08:05:25PM +0000, Dr. David Alan Gilbert wrote: > * 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.
And maybe mention VHOST_USER_PROTOCOL_F_PAGEFAULT here too. > 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