> I agree with that, but there exist also other code in hwsim, which is >> tightly coupled with the mac80211 API, as e.g., the usage of >> IEEE80211_TX_MAX_RATES, which already broke older versions of >> wmediumd or similar implementations. Maybe a review regarding such >> things would be good to decouple the userspace daemon from the >> special kernel version. > Agree. It'd be better if that were using nested attributes etc. > Although then again, to really decouple this we should make hwsim > behave towards wmediumd more like real hardware would, and have it pass > just a single rate to userspace, with only success/fail indication > coming back - if it fails, it could walk down the chain of rates > itself. Right now we let wmediumd do this, which is why we have all > these API internals exposed to it. Mhh, I thought also some atheros drivers implement hardware multirate retry changes, which maps to this struct. Only one rate per frame would introduce a extreme additional communication overhead, which will make testing with standard wmediumd impractical. I think we need to keep such a structure, but we should align that with other mac80211 depended drivers. > >>>> but I think that will break up the communication to e.g. bob >>>> copelands >>>> wmediumd and similar simulations. I would like to have our >>>> Implementation working with mainline kernels and therefore ask >>>> how we >>>> could achieve this easily. >>>> >>>> Obviously, we could define another field in the hwsim messages, >>>> but >>>> as bob copeland already stated, significantly more information >>>> within >>>> the netlink messages could intensify the timing overhead of >>>> hwsim. >>> I don't think we have any other choice but add the relevant fields >>> as >>> proper attributes. >> I'm totally fine with that. Nonetheless, I would suggest to add the >> flags to "struct hwsim_tx_rate", since the flags are also tightly >> coupled to the rates and tries of a frame. To not break up things, we >> could add the flags as a separate attribute in the struct and not as >> part of the bitfield like in the original. This would be possible, >> due >> to the "__packed" flag, but I'm also unsure, whether this is a really >> good idea for a userspace API/ABI. > Changing the struct size itself would break ABI though?
You are totally right ... I was a bit absent. But the point is, without the rates and tries, the flags are useless, so I think it is better to put them together, but I'm also fine with another attribute ;-) Benjamin
