On Sat, Apr 17, 2021 at 11:13:51AM -0700, Jakub Kicinski wrote: > On Sat, 17 Apr 2021 10:57:42 -0700 Jakub Kicinski wrote: > > > I tried to understand how you add new groups without user space > > > changes and I think this statement is not entirely accurate. > > > > > > At minimum, user space needs to know the names of these groups, but > > > currently there is no way to query the information, so it's added to > > > ethtool's help message: > > > > > > ethtool [ FLAGS ] -S|--statistics DEVNAME Show adapter statistics > > > > > > [ --groups [eth-phy] [eth-mac] [eth-ctrl] [rmon] ] > > > > Um, yes and now. The only places the user space puts those names > > is the help message and man page. > > > > Thru the magic of bitsets it doesn't actually interpret them, so > > with old user space you can still query a new group, it will just > > not show up in "ethtool -h". > > > > Is that what you're saying? > > FWIW ethnl_parse_bit() -> ETHTOOL_A_BITSET_BIT_NAME > User space can also use raw flags like --groups 0xf but that's perhaps > too spartan for serious use.
So the kernel can work with ETHTOOL_A_BITSET_BIT_INDEX / ETHTOOL_A_BITSET_BIT_NAME, but I was wondering if using ethtool binary we can query the strings that the kernel will accept. I think not? Anyway, I'm fine with implementing '--all-groups' via ETHTOOL_MSG_STRSET_GET. We can always add a new attribute later, but I don't see a reason to do so.
