Re: rtcwake doesn't reset wakealarm

[Karel Zak <kzak@redhat.com>]

On Wed, Sep 12, 2012 at 12:09:16PM +0200, Karel Zak wrote:
> 
>  Let's add Paul to CC ;-)
> 
> On Wed, Sep 12, 2012 at 09:52:14AM +0000, Giacomo wrote:
> > 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:

 Please, test the patch below. I hope it fixes the problem.

    Karel



>From 7413ac3f50102236415267f19b23f9839a6403b0 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Wed, 12 Sep 2012 12:22:13 +0200
Subject: [PATCH] rtcwake: reset wakealarm

> 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.

Reported-by: Giacomo <giacomo.perale@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
---
 sys-utils/rtcwake.c |   12 +++++++-----
 1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/sys-utils/rtcwake.c b/sys-utils/rtcwake.c
index 0e16bd3..6e2701a 100644
--- a/sys-utils/rtcwake.c
+++ b/sys-utils/rtcwake.c
@@ -64,7 +64,7 @@ enum ClockMode {
 
 static unsigned		verbose;
 static unsigned		dryrun;
-static unsigned		ioctl_aie_on;  /* ioctl(AIE_ON) succeeded */
+static unsigned		alarm_on;  /* RTC_ALM_SET+RTC_AIE_ON or RTC_WKALM_SET */
 enum ClockMode		clock_mode = CM_AUTO;
 
 static struct option long_options[] = {
@@ -243,12 +243,13 @@ static int setup_alarm(int fd, time_t *wakeup)
 				warn(_("enable rtc alarm failed"));
 				return -1;
 			}
-			ioctl_aie_on = 1;
+			alarm_on = 1;
 		} else {
 			warn(_("set rtc wake alarm failed"));
 			return -1;
 		}
-	}
+	} else if (!dryrun)
+		alarm_on = 1;
 
 	return 0;
 }
@@ -524,6 +525,7 @@ int main(int argc, char **argv)
 				alarm, sys_time, rtc_time, seconds);
 
 	if (strcmp(suspend, "show") && strcmp(suspend, "disable")) {
+
 		if (strcmp(suspend, "no") && strcmp(suspend, "on") &&
 		    strcmp(suspend, "off") && is_suspend_available(suspend) <= 0) {
 			errx(EXIT_FAILURE, _("suspend to \"%s\" unavailable"), suspend);
@@ -598,7 +600,7 @@ int main(int argc, char **argv)
 		}
 
 	} else if (strcmp(suspend, "disable") == 0) {
-		/* just break, alarm gets disabled in the end */
+		alarm_on = 1;  /* alarm gets disabled in the end */
 		if (verbose)
 			printf(_("suspend mode: disable; disabling alarm\n"));
 
@@ -616,7 +618,7 @@ int main(int argc, char **argv)
 		suspend_system(suspend);
 	}
 
-	if (!dryrun && ioctl_aie_on && ioctl(fd, RTC_AIE_OFF, 0) < 0)
+	if (!dryrun && alarm_on && ioctl(fd, RTC_AIE_OFF, 0) < 0)
 		warn(_("disable rtc alarm interrupt failed"));
 
 	close(fd);
-- 
1.7.7.6