Re: [Qemu-devel] [PATCH 3/3] tests: enable virtio tests on SPAPR

[John Snow]

On 09/30/2016 06:30 AM, Laurent Vivier wrote:
> On 30/09/2016 12:18, Greg Kurz wrote:
> > On Thu, 29 Sep 2016 19:15:07 +0200
> > Laurent Vivier <address@hidden> wrote:
> >
> > > but disable MSI-X tests on SPAPR as we can't check the result
> > > (the memory region used on PC is not readable on SPAPR).
> > >
> > > Signed-off-by: Laurent Vivier <address@hidden>
> > > ---
> > >  tests/Makefile.include    |  3 ++-
> > >  tests/libqos/virtio-pci.c | 22 ++++++++++++++++++++--
> > >  tests/virtio-9p-test.c    | 11 ++++++++++-
> > >  tests/virtio-blk-test.c   | 22 +++++++++++++++++-----
> > >  tests/virtio-net-test.c   | 17 +++++++++++++++--
> > >  tests/virtio-rng-test.c   |  7 ++++++-
> > >  tests/virtio-scsi-test.c  | 10 +++++++++-
> > >  7 files changed, 79 insertions(+), 13 deletions(-)
> ...
> > > diff --git a/tests/virtio-9p-test.c b/tests/virtio-9p-test.c
> > > index 28d7f5b..a73bccb 100644
> > > --- a/tests/virtio-9p-test.c
> > > +++ b/tests/virtio-9p-test.c
> > > @@ -11,6 +11,7 @@
> > >  #include "libqtest.h"
> > >  #include "qemu-common.h"
> > >  #include "libqos/libqos-pc.h"
> > > +#include "libqos/libqos-spapr.h"
> > >  #include "libqos/virtio.h"
> > >  #include "libqos/virtio-pci.h"
> > >  #include "standard-headers/linux/virtio_ids.h"
> > > @@ -22,12 +23,20 @@ static char *test_share;
> > >
> > >  static QOSState *qvirtio_9p_start(void)
> > >  {
> > > +    const char *arch = qtest_get_arch();
> > > +    QOSState *qs = NULL;
> > >      test_share = g_strdup("/tmp/qtest.XXXXXX");
> > >      g_assert_nonnull(mkdtemp(test_share));
> > >      const char *cmd = "-fsdev local,id=fsdev0,security_model=none,path=%s "
> > >                        "-device virtio-9p-pci,fsdev=fsdev0,mount_tag=%s";
> > >
> > > -    return qtest_pc_boot(cmd, test_share, mount_tag);
> > > +    if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
> > > +        qs = qtest_pc_boot(cmd, test_share, mount_tag);
> > > +    } else if (strcmp(arch, "ppc64") == 0) {
> > > +        qs = qtest_spapr_boot(cmd, test_share, mount_tag);
> > > +    }
> > > +
> >
> > What about introducing a qtest_arch_boot() helper that does ^^ and
> >
> > } else {
> >     g_printerr("qtest_arch_boot() not supported for arch %s\n",
> >                qtest_get_arch());
> >     exit(EXIT_FAILURE);
> > }
>
> The problem with adding a function like that is it will pull
> $(libqos-pc-obj-y) and  $(libqos-spapr-obj-y) for every tests using it,
> and for the moment we are pulling pc or spapr objects only if we need
> them for the given test.
>
> I think it explains why qtest_pc_boot() calls qtest_vboot() and we don't
> have a generic qtest_boot() calling the architecture specific function.
>
> I cc: John Snow as he has written the initial code for this.
> ("90e5add libqos: add pc specific interface")
>
> Laurent

This was a while ago for me (and I was brand new to QEMU!), but that 
sounds about right. I wasn't able to reason about requirements for other 
architectures, so we made the PC-specific frontend to do the 
configuration for us. libqos.o does not pull in any of the PC-specific 
requirements as a result. Neither does the allocator.

I didn't necessarily design it to be like this, just a path of least 
resistance type of thing.

You probably could make an ArchOps callback structure if you wanted and 
pass that along to a generic bootup function to avoid the linking issues 
if you wanted a one-size-fits-all initialization function.

--js