Re: [Qemu-devel] [for-4.2 PATCH 0/6] Block-related record/replay fixes

["Pavel Dovgalyuk" <dovgaluk@ispras.ru>]

> -----Original Message-----
> From: Alex Bennée [mailto:alex.bennee@linaro.org]
> Sent: Tuesday, September 17, 2019 10:02 PM
> To: Pavel Dovgalyuk
> Cc: qemu-devel@nongnu.org; kwolf@redhat.com; peter.maydell@linaro.org;
> crosthwaite.peter@gmail.com; boost.lists@gmail.com; artem.k.pisarenko@gmail.com;
> quintela@redhat.com; ciro.santilli@gmail.com; jasowang@redhat.com; mst@redhat.com;
> armbru@redhat.com; mreitz@redhat.com; maria.klimushenkova@ispras.ru; dovgaluk@ispras.ru;
> kraxel@redhat.com; pavel.dovgaluk@ispras.ru; thomas.dullien@googlemail.com;
> pbonzini@redhat.com; dgilbert@redhat.com; rth@twiddle.net
> Subject: Re: [for-4.2 PATCH 0/6] Block-related record/replay fixes
> 
> 
> Pavel Dovgalyuk <pavel.dovgaluk@gmail.com> writes:
> 
> > The set of patches include the block-related updates
> > of the record/replay icount feature:
> >  - application of 'snapshot' option on the file layer instead of
> >    the top one: command line and documentation fix
> >  - implementation of bdrv_snapshot_goto for blkreplay driver
> >  - start/stop fix in replay mode with attached block devices
> >  - record/replay of bh oneshot events, used in the block layer
> 
> Can we come up with a reasonable smoke test to verify record/replay is
> functional? AIUI we don't need a full OS but we do need a block device
> to store the replay data. Could we use one of the simple system tests
> like "memory" and run that through a record and replay cycle?

That's would be great.
I'm not familiar with testing framework and couldn't find "memory" test that you refer to.
Replay test must at least the following:
1. record some execution
2. replay that execution

And there could be several endings:
1. record stalled
2. record crashed
3. replay stalled
4. replay crashed
5. all executions finished successfully

Pavel Dovgalyuk

> 
> >
> > ---
> >
> > Pavel Dovgaluk (6):
> >       block: implement bdrv_snapshot_goto for blkreplay
> >       replay: disable default snapshot for record/replay
> >       replay: update docs for record/replay with block devices
> >       replay: don't drain/flush bdrv queue while RR is working
> >       replay: finish record/replay before closing the disks
> >       replay: add BH oneshot event for block layer
> >
> >
> >  block/blkreplay.c        |    8 ++++++++
> >  block/block-backend.c    |    9 ++++++---
> >  block/io.c               |   32 ++++++++++++++++++++++++++++++--
> >  block/iscsi.c            |    5 +++--
> >  block/nfs.c              |    6 ++++--
> >  block/null.c             |    4 +++-
> >  block/nvme.c             |    6 ++++--
> >  block/rbd.c              |    5 +++--
> >  block/vxhs.c             |    5 +++--
> >  cpus.c                   |    2 --
> >  docs/replay.txt          |   12 +++++++++---
> >  include/sysemu/replay.h  |    4 ++++
> >  replay/replay-events.c   |   16 ++++++++++++++++
> >  replay/replay-internal.h |    1 +
> >  replay/replay.c          |    2 ++
> >  stubs/Makefile.objs      |    1 +
> >  stubs/replay-user.c      |    9 +++++++++
> >  vl.c                     |   11 +++++++++--
> >  18 files changed, 115 insertions(+), 23 deletions(-)
> >  create mode 100644 stubs/replay-user.c
> 
> 
> --
> Alex Bennée