On 1 June 2017 at 06:24, Kalle Valo <kvalo@xxxxxxxxxxxxxxxx> wrote: > Arend van Spriel <arend.vanspriel@xxxxxxxxxxxx> writes: > >> On 31-05-17 14:16, Kalle Valo wrote: >>> Adrian Chadd <adrian@xxxxxxxxxxx> writes: >>> >>>> This adds a few configurable debugging options: >>>> >>>> * driver debugging and tracing is now configurable per device >>>> * driver debugging and tracing is now configurable at runtime >>>> * the debugging / tracing is not run at all (besides a mask check) >>>> unless the specific debugging bitmap field is configured. >>>> >>>> Signed-off-by: Adrian Chadd <adrian@xxxxxxxxxxx> >>> >>> [...] >>> >>>> --- a/drivers/net/wireless/ath/ath10k/core.c >>>> +++ b/drivers/net/wireless/ath/ath10k/core.c >>>> @@ -2444,6 +2444,8 @@ struct ath10k *ath10k_core_create(size_t >>>> priv_size, struct device *dev, >>>> ar->hw_rev = hw_rev; >>>> ar->hif.ops = hif_ops; >>>> ar->hif.bus = bus; >>>> + ar->debug_mask = ath10k_debug_mask; >>>> + ar->trace_debug_mask = ath10k_debug_mask; >>> >>> Until now tracing has been always enabled, irrespective what debug_mask >>> has contained. Now you are changing that and by default log messages are >>> not delivered through tracing until user enables them. So I think to >>> keep the old behaviour trace_debug_mask should be ATH10K_DBG_ANY >>> (0xffffffff) by default and the user can modify the mask per device via >>> the debugfs file. >>> >>> But is it really needed to be able to filter trace messages? debug_mask >>> I understand, but not sure about trace_debug_mask. >> >> FWIW, in brcmfmac I decided not to filter trace messages. The overhead >> is relatively small and if needed you can pass filter expressions with >> trace-cmd record. > > I also think that this is how it should work. For example, if you have > tracing enabled in wpasupplicant/hostapd with the command below you can > get a lot of information in one file with relatively little overhead: > > trace-cmd record -e mac80211 -e cfg80211 -e ath10k > > But if user is forced to use debugfs to enable ath10k tracing that is > quite a step backwards. > I agree that is how it should work, but i can't see how you do it on ath10k without the debug overhead always being there. If there's a way to know /a/ trace watch is going on from the kernel then it could be flipped on for that, but i didn't see any obvious "trace enable" / "trace disable" hooks. -a
