Re: [PATCH v3 bpf-next 10/10] selftests/bpf: cgroup local storage-based network counters

[Alexei Starovoitov]

On Fri, Sep 28, 2018 at 11:37:26AM +0100, Roman Gushchin wrote:
> > > > > +
> > > > > +	/* Let's check that bytes counter value is reasonable */
> > > > > +	if (netcnt.bytes < packets * 500 || netcnt.bytes > packets * 1500) {
> > > > 
> > > > since packet count is accurate why byte count would vary ?
> > > 
> > > Tbh I'm not sure if the size of the packet here can vary depending
> > > on the environment. Is there a nice way to get the expected size?
> > 
> > ping packets should be fixed size depending on v4 vs v6.
> > If 'ping -6' is used, it will force ipv6.
> > 
> 
> Are we ok to screw up kselftests on v4-only machines?

we already did. Some of the selftests/bpf use ping -6 already.