On Wed, Sep 1, 2021 at 1:41 PM Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > > On Wed, Sep 1, 2021 at 11:25 PM Brian Norris <briannorris@xxxxxxxxxxxx> wrote: > > On Mon, Aug 30, 2021 at 5:37 AM Jonas Dreßler <verdre@xxxxxxx> wrote: > > ... > > > This might be good for many cases, but please read this commit: > > > > https://git.kernel.org/linus/062e008a6e83e7c4da7df0a9c6aefdbc849e2bb3 > > mwifiex: pcie: use posted write to wake up firmware > > > > It's very much intentional that this is a posted write in some cases. > > > > Without ensuring this doesn't regress, NAK from me. > > Can you ensure that from Chrome / Google perspective, please? I mean, the context link should be pretty obvious. But sure: with this patch: (a) all my least-favorite audio issues to debug return (audio is especially latency-sensitive on the Rockchip RK3399 systems I have) (b) latency spikes to ~6ms: # trace-cmd record -p function_graph -O funcgraph-abstime -l mwifiex_pm_wakeup_card # trace-cmd report kworker/u13:0-199 [003] 348.987306: funcgraph_entry: # 6219.500 us | mwifiex_pm_wakeup_card(); kworker/u13:0-199 [003] 349.316312: funcgraph_entry: # 6267.625 us | mwifiex_pm_wakeup_card(); kworker/u13:3-4057 [001] 352.238530: funcgraph_entry: # 6184.250 us | mwifiex_pm_wakeup_card(); kworker/u13:0-199 [002] 356.626366: funcgraph_entry: # 6553.166 us | mwifiex_pm_wakeup_card(); kworker/u13:3-4057 [002] 356.709389: funcgraph_entry: # 6212.500 us | mwifiex_pm_wakeup_card(); kworker/u13:3-4057 [002] 356.847215: funcgraph_entry: # 6230.292 us | mwifiex_pm_wakeup_card(); kworker/u13:3-4057 [000] 356.897576: funcgraph_entry: # 6451.667 us | mwifiex_pm_wakeup_card(); kworker/u13:0-199 [004] 357.175025: funcgraph_entry: # 6204.042 us | mwifiex_pm_wakeup_card(); whereas it used to look more like: kworker/u13:1-173 [005] 212.230542: funcgraph_entry: 7.000 us | mwifiex_pm_wakeup_card(); kworker/u13:3-1768 [005] 213.886063: funcgraph_entry: 9.334 us | mwifiex_pm_wakeup_card(); kworker/u13:3-1768 [002] 214.473273: funcgraph_entry: + 11.375 us | mwifiex_pm_wakeup_card(); kworker/u13:3-1768 [005] 214.530705: funcgraph_entry: 5.542 us | mwifiex_pm_wakeup_card(); kworker/u13:1-173 [002] 215.050168: funcgraph_entry: + 13.125 us | mwifiex_pm_wakeup_card(); kworker/u13:1-173 [002] 215.106492: funcgraph_entry: + 11.959 us | mwifiex_pm_wakeup_card(); kworker/u13:3-1768 [005] 215.484807: funcgraph_entry: 8.459 us | mwifiex_pm_wakeup_card(); kworker/u13:1-173 [003] 215.515238: funcgraph_entry: + 15.166 us | mwifiex_pm_wakeup_card(); kworker/u13:3-1768 [001] 217.175691: funcgraph_entry: + 11.083 us | mwifiex_pm_wakeup_card(); I think it would be enough to only modify mwifiex_pm_wakeup_card() to retain the posted version, but I'm not sure how that fits in with the rest of the author's work. I suppose I can give a later version a run if needed. Brian
