[Accel-config] Re: [PATCH] accel-config/test: load/unload uacce module at cleanup

On Tue, Apr 06, 2021 at 08:55:43AM -0700, Dave Jiang wrote:
> 
> On 4/5/2021 5:45 PM, ramesh.thomas(a)intel.com wrote:
> > From: Ramesh Thomas <ramesh.thomas(a)intel.com>
> >
> > Cleanup unloads and reloads all idxd kernel modules. This is broken due
> > to idxd_module depending on idxd module. The order of idxd_mdev and
> > idxd_uacce modules are not fixed requiring additional checks during the
> > process.
> >
> > Signed-off-by: Tony Zhu <tony.zhu(a)intel.com>
> > Signed-off-by: Ramesh Thomas <ramesh.thomas(a)intel.com>
> 
> I would maybe add a comment explaining the weird behavior observed.

I have a new finding. Even though "modprobe -r" returns failure and
prints error message "modprobe: FATAL: Module idxd is in use.", the
module is still unloaded. It does not give that error on the second
module that is unloaded so I earlier thought it has to do with the
order. This seems to be a bug in the driver and is easily reproducible.

Since it returns failure, the test script aborts with error. I will
modify the workaround to not trap on the error and continue. That way we
don't need the second unload attempt of the same module. I will add
a comment describing this as a workaround for the above behavior. 


> 
> Reviewed-by: Dave Jiang <dave.jiang(a)intel.com>
> 
> 
> > ---
> >   test/common | 9 +++++++++
> >   1 file changed, 9 insertions(+)
> >
> > diff --git a/test/common b/test/common
> > index 4bd4ed3..e6e84dd 100644
> > --- a/test/common
> > +++ b/test/common
> > @@ -99,6 +99,14 @@ check_prereq()
> >   #
> >   _cleanup()
> >   {
> > +	lsmod | grep -q "idxd_mdev" && {
> > +		modprobe -r idxd_mdev 2>/dev/null || :
> > +		sleep 1
> > +	}
> > +	lsmod | grep -q "idxd_uacce" && {
> > +		modprobe -r idxd_uacce
> > +		sleep 1
> > +	}
> >   	lsmod | grep -q "idxd_mdev" && {
> >   		modprobe -r idxd_mdev
> >   		sleep 1
> > @@ -108,6 +116,7 @@ _cleanup()
> >   		sleep 1
> >   	}
> >   	modprobe idxd
> > +	sleep 1
> >   }
> >
> >   # json2var