Re: [PATCH] dell-smm-hwmon: Cache fan_type() calls and use fan_status() for fan detection

From: Thorsten Leemhuis
Date: Fri May 27 2016 - 04:00:14 EST


Pali RohÃr wrote on 26.05.2016 17:51:
> On Thursday 26 May 2016 17:39:57 Thorsten Leemhuis wrote:
>> > I need to know if this patch fixes problem on Dell Studio XPS 8000
>> > and Dell Studio XPS 8100 machines, so we can revert git commits:
>> > 6220f4ebd7b4 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8000")
>> > a4b45b25f18d ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8100")
>> Just checked: Sorry, that patch did not fix the CPU fan speed issue
>> on my XPS 8000, so there is afaics no reason to revert 6220f4ebd7b4
>> :-/
> Please, can you apply patch "dell-smm-hwmon: In debug mode log duration
> of SMM calls"

On top of "Cache fan_type() calls and use fan_status() for fan
detection" or with that patch reverted? I did the latter and
tested with 4.6 (just mentioning it here in case it matters).

> and compile dell-smm-hwmon in debug mode to tell us which
> SMM call takes too long? This is probably they key for that XPS
> problems...

[ 5.941037] dell_smm_hwmon: smm(0xfea3 0x0000) = 0x4147 (took 14470 usecs)
[ 5.941139] dell_smm_hwmon: smm(0x11a3 0x0000) = 0xffff (took 93 usecs)
[ 5.941236] dell_smm_hwmon: smm(0x11a3 0x0001) = 0xffff (took 93 usecs)
[ 5.941331] dell_smm_hwmon: smm(0x11a3 0x0002) = 0xffff (took 92 usecs)
[ 5.941427] dell_smm_hwmon: smm(0x11a3 0x0003) = 0xffff (took 92 usecs)
[ 5.941526] dell_smm_hwmon: smm(0x03a3 0x0000) = 0x0000 (took 95 usecs)
[ 5.941625] dell_smm_hwmon: smm(0x03a3 0x0001) = 0x0001 (took 95 usecs)

HTH, CU, knurd