Re: rtcwake doesn't reset wakealarm

[Giacomo <giacomo.perale@gmail.com>]

Giacomo <giacomo.perale@...> writes:

> I recently upgraded to util-linux 2.22 and I noticed that powertop started
> reporting about 50-60 wakeups per second caused by rtc (interrupt 8). 
> 
> I quickly found out that this happened when I used rtcwake to wake up the
> machine, and that after the reboot /sys/class/rtc/rtc0/wakealarm was still 
> set to the scheduled wakeup time (now in the past). 
> 
> After a quick investigation I discovered that this is caused by commit
> 1707576155daf644c5df3c1776b52fd297ff9318 ("rtcwake: only invoke RTC_AIE_ON/OFF
> ioctls in pairs"): my system uses RTC_WKALM_SET so ioctl_aie_on stays false and
> RTC_AIE_OFF doesn't get called.
> 

Hi,

that commit also broke "disable". This is what happens on my system:

KazeNoTani ~ # cat /sys/class/rtc/rtc0/wakealarm
KazeNoTani ~ # rtcwake -m show
alarm: off
KazeNoTani ~ # rtcwake -m no -s 300
rtcwake: wakeup using /dev/rtc0 at Wed Sep 12 09:40:31 2012
KazeNoTani ~ # rtcwake -m show
alarm: on  Wed Sep 12 09:40:32 2012
KazeNoTani ~ # cat /sys/class/rtc/rtc0/wakealarm
1347442831
KazeNoTani ~ # rtcwake -m disable
KazeNoTani ~ # rtcwake -m show
alarm: on  Wed Sep 12 09:40:32 2012
KazeNoTani ~ # cat /sys/class/rtc/rtc0/wakealarm
1347442831
KazeNoTani ~ # echo 0 > /sys/class/rtc/rtc0/wakealarm
KazeNoTani ~ # cat /sys/class/rtc/rtc0/wakealarm
KazeNoTani ~ # rtcwake -m show
alarm: off


rtcwake -m disable doesn't remove the alarm. This is because as it is
implemented now "-m disable" does nothing but break and rely on the call to
RTC_AIE_OFF that was always done at the end of the execution of rtcwake, but now
is conditional on "ioctl_aie_on" that doesn't get set in most cases.

Thanks,

Giacomo