| Message ID | 20220829144147.484787-1-jelonek.jonas@gmail.com |
|---|---|
| Headers | show |
| Series | mac80211: add TPC support in control path | expand |
> On 29. Aug 2022, at 17:06, Jonas Jelonek <jelonek.jonas@gmail.com> wrote: > > We planned to get these changes upstream at first to have the foundation for TPC > in the mac80211, and then develop driver implementations and TPC algorithm on > top of this once all is reviewed, approved and upstream. > The ath9k tpc support is currently not upstream-ready but can be in a next version. > For testing the actual TPC support I modified minstrel’s debugfs to be able to set > fixed tx-power per STA. > > I think we can develop this series further to come up with fully working driver > implementation and a TPC algorithm if you think that would be better. > Else we could also provide at least a debugfs patch to be able to set fixed > tx-power per STA. > > Greetings > Jonas > >> On 29. Aug 2022, at 16:46, Johannes Berg <johannes@sipsolutions.net> wrote: >> >> On Mon, 2022-08-29 at 16:41 +0200, Jonas Jelonek wrote: >>> >>> I tested the tx-power annotation with an implementation of TPC in ath9k >>> (not included in this RFC) and small changes in minstrel_ht for debugfs >>> access. Tx-power status report in ath9k required the proposed utility >>> function in mac80211. >>> >> >> Huh wait, now that I got to the end of the series ... this doesn't >> actually *do* anything, so what's the point? Shouldn't it come with some >> implementation of the control? >> >> johannes > I am working on the hwsim support right now, tpc support in hwsim’s control path is implemented. However I encountered a problem in the status path. Hwsim seems to hand over to mac80211 tx-status asynchronously via ieee80211_tx_status_irqsafe only. There, the skb is added to ieee80211_local->skb_queue and then dequeued in ‘ieee80211_tasklet_handler’ to be passed to ‘ieee80211_tx_status’. For tx rates this is sufficient, but there is no space left in ieee80211_tx_info->status to pass the tx-power per packet. Please correct me if I missed something in the code. My idea to solve this may be: to use the SKB extension (struct skb_ext *extensions) to pass the tx-power information (and maybe more) for each SKB. Could this be an appropriate approach or do I miss something here? Maybe someone who is much more aware of the mac80211 layer design does have a better idea for this? Greetings Jonas
Transmit power control (TPC) per packet hence per station can be used to manage interference and increase overall spatial reuse and therefore increases sum throughput in WiFi networks with multiple APs and STAs. Although several of today's wifi chips, e.g., from QCA and from Mediatek support fine-grained TPC per packet, the Linux mac80211 layer does not provide support this annotation nor control yet. This series proposes several changes to introduce TPC support in mac80211, in particular to annotate tx-power per packet/per mrr stage in the Tx control path. The patches include new nembers in the Tx control path structs, a modified tx-power level support annotation, hardware flags and an utility function for the convenient use of struct ieee80211_rate_status (introduced by 44fa75f207d8a106bc75e6230db61e961fdbf8a8) for tx-power status report in drivers. Compile-Tested: current wireless-next tree with all flags on Tested-on PCEngines APU with ath9k WiFi device on OpenWrt Linux Kernel 5.10.137 I tested the tx-power annotation with an implementation of TPC in ath9k (not included in this RFC) and small changes in minstrel_ht for debugfs access. Tx-power status report in ath9k required the proposed utility function in mac80211. Signed-off-by: Thomas Huehn <thomas.huehn@hs-nordhausen.de> Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com> Jonas Jelonek (4): mac80211: modify tx-power level annotation mac80211: add tx-power annotation in control path mac80211: add hardware flags for TPC support mac80211: add utility function for tx_rate - rate_info conversion include/net/mac80211.h | 60 +++++++++++++++++++++++++++++++++++------- net/mac80211/debugfs.c | 2 ++ net/mac80211/util.c | 35 ++++++++++++++++++++++++ 3 files changed, 87 insertions(+), 10 deletions(-)