[Xenomai-core] Make watchdog-timer configurable

[Xenomai-core] Make watchdog-timer configurable

[Johan Borkhuis]

I made the following change to Xenomai (version 2.3.2, but it could also 
be applied to 2.4 as the watchdog code has not been changed).

The watchdog timeout is fixed at 4 seconds. For us this is a problem as 
there are some processes that take more time than this.

I made the following change to allow this to be changed through the 
Linux kernel configuration. The value is configurable between 1 and 60 
seconds.

Below is a patchfile that implements this change. Please let me know if 
you have comments on this, or if there are problems with this change.

================
diff -u -r org/xenomai-2.3.2/ksrc/nucleus/Kconfig 
xenomai-2.3.2/ksrc/nucleus/Kconfig
--- org/xenomai-2.3.2/ksrc/nucleus/Kconfig      2007-07-06 
18:42:14.000000000 +0200
+++ xenomai-2.3.2/ksrc/nucleus/Kconfig  2007-09-04 14:13:41.000000000 +0200
@@ -172,6 +172,17 @@
        behalf of the timer tick handler, thus is only active after
        the timer has been started.
 
+config XENO_OPT_WATCHDOG_PERIOD
+       depends on XENO_OPT_WATCHDOG
+       int "Watchdog period (s)"
+       default 4
+    range 1 60
+       help
+
+    Nr of seconds of uninterrupted real-time activity after which
+    the watchdog triggers.
+
+
 menu "Timing"
 
 config XENO_OPT_TIMING_PERIODIC
diff -u -r org/xenomai-2.3.2/ksrc/nucleus/pod.c 
xenomai-2.3.2/ksrc/nucleus/pod.c
--- org/xenomai-2.3.2/ksrc/nucleus/pod.c        2007-07-07 
10:18:57.000000000 +0200
+++ xenomai-2.3.2/ksrc/nucleus/pod.c    2007-09-04 14:06:35.000000000 +0200
@@ -2925,7 +2925,7 @@
        return nkpod->svctable.faulthandler(fltinfo);
 }
 
-#ifdef CONFIG_XENO_OPT_WATCHDOG
+#if (defined CONFIG_XENO_OPT_WATCHDOG) && 
(CONFIG_XENO_OPT_WATCHDOG_PERIOD > 0)
 
 /*!
  * @internal
@@ -2948,7 +2948,7 @@
                return;
        }
 
-       if (unlikely(++sched->wd_count >= 4)) {
+       if (unlikely(++sched->wd_count >= 
CONFIG_XENO_OPT_WATCHDOG_PERIOD)) {
                xnltt_log_event(xeno_ev_watchdog, thread->name);
                xnprintf("watchdog triggered -- killing runaway thread 
'%s'\n",
                         thread->name);

================

Kind regards,
    Johan Borkhuis

Re: [Xenomai-core] Make watchdog-timer configurable

[Philippe Gerum]

On Tue, 2007-09-04 at 15:12 +0200, Johan Borkhuis wrote:
> I made the following change to Xenomai (version 2.3.2, but it could also 
> be applied to 2.4 as the watchdog code has not been changed).
> 
> The watchdog timeout is fixed at 4 seconds. For us this is a problem as 
> there are some processes that take more time than this.
> 
> I made the following change to allow this to be changed through the 
> Linux kernel configuration. The value is configurable between 1 and 60 
> seconds.
> 
> Below is a patchfile that implements this change. Please let me know if 
> you have comments on this, or if there are problems with this change.
> 

Looks good. Will merge, thanks.

> ================
> diff -u -r org/xenomai-2.3.2/ksrc/nucleus/Kconfig 
> xenomai-2.3.2/ksrc/nucleus/Kconfig
> --- org/xenomai-2.3.2/ksrc/nucleus/Kconfig      2007-07-06 
> 18:42:14.000000000 +0200
> +++ xenomai-2.3.2/ksrc/nucleus/Kconfig  2007-09-04 14:13:41.000000000 +0200
> @@ -172,6 +172,17 @@
>         behalf of the timer tick handler, thus is only active after
>         the timer has been started.
>  
> +config XENO_OPT_WATCHDOG_PERIOD
> +       depends on XENO_OPT_WATCHDOG
> +       int "Watchdog period (s)"
> +       default 4
> +    range 1 60
> +       help
> +
> +    Nr of seconds of uninterrupted real-time activity after which
> +    the watchdog triggers.
> +
> +
>  menu "Timing"
>  
>  config XENO_OPT_TIMING_PERIODIC
> diff -u -r org/xenomai-2.3.2/ksrc/nucleus/pod.c 
> xenomai-2.3.2/ksrc/nucleus/pod.c
> --- org/xenomai-2.3.2/ksrc/nucleus/pod.c        2007-07-07 
> 10:18:57.000000000 +0200
> +++ xenomai-2.3.2/ksrc/nucleus/pod.c    2007-09-04 14:06:35.000000000 +0200
> @@ -2925,7 +2925,7 @@
>         return nkpod->svctable.faulthandler(fltinfo);
>  }
>  
> -#ifdef CONFIG_XENO_OPT_WATCHDOG
> +#if (defined CONFIG_XENO_OPT_WATCHDOG) && 
> (CONFIG_XENO_OPT_WATCHDOG_PERIOD > 0)
>  
>  /*!
>   * @internal
> @@ -2948,7 +2948,7 @@
>                 return;
>         }
>  
> -       if (unlikely(++sched->wd_count >= 4)) {
> +       if (unlikely(++sched->wd_count >= 
> CONFIG_XENO_OPT_WATCHDOG_PERIOD)) {
>                 xnltt_log_event(xeno_ev_watchdog, thread->name);
>                 xnprintf("watchdog triggered -- killing runaway thread 
> '%s'\n",
>                          thread->name);
> 
> ================
> 
> Kind regards,
>     Johan Borkhuis
> 
> 
> _______________________________________________
> Xenomai-core mailing list
> Xenomai-core@domain.hid
> https://mail.gna.org/listinfo/xenomai-core
-- 
Philippe.

Re: [Xenomai-core] Make watchdog-timer configurable

[Gilles Chanteperdrix]

Philippe Gerum wrote:
 > On Tue, 2007-09-04 at 15:12 +0200, Johan Borkhuis wrote:
 > > I made the following change to Xenomai (version 2.3.2, but it could also 
 > > be applied to 2.4 as the watchdog code has not been changed).
 > > 
 > > The watchdog timeout is fixed at 4 seconds. For us this is a problem as 
 > > there are some processes that take more time than this.
 > > 
 > > I made the following change to allow this to be changed through the 
 > > Linux kernel configuration. The value is configurable between 1 and 60 
 > > seconds.
 > > 
 > > Below is a patchfile that implements this change. Please let me know if 
 > > you have comments on this, or if there are problems with this change.
 > > 
 > 
 > Looks good. Will merge, thanks.

I have nothing against the patch.

That said, if you have a real-time activity that does not let Linux run
for 4 seconds, you are risking some troubles when the real-time activity
gives back the control to Linux, such as random lockups for example.

-- 


					    Gilles Chanteperdrix.

Re: [Xenomai-core] Make watchdog-timer configurable

[Philippe Gerum]

On Wed, 2007-09-05 at 16:47 +0200, Gilles Chanteperdrix wrote:
> Philippe Gerum wrote:
>  > On Tue, 2007-09-04 at 15:12 +0200, Johan Borkhuis wrote:
>  > > I made the following change to Xenomai (version 2.3.2, but it could also 
>  > > be applied to 2.4 as the watchdog code has not been changed).
>  > > 
>  > > The watchdog timeout is fixed at 4 seconds. For us this is a problem as 
>  > > there are some processes that take more time than this.
>  > > 
>  > > I made the following change to allow this to be changed through the 
>  > > Linux kernel configuration. The value is configurable between 1 and 60 
>  > > seconds.
>  > > 
>  > > Below is a patchfile that implements this change. Please let me know if 
>  > > you have comments on this, or if there are problems with this change.
>  > > 
>  > 
>  > Looks good. Will merge, thanks.
> 
> I have nothing against the patch.
> 
> That said, if you have a real-time activity that does not let Linux run
> for 4 seconds, you are risking some troubles when the real-time activity
> gives back the control to Linux, such as random lockups for example.
> 

You could also use this feature to lower the deadline below 4 secs,
which is already pretty high.

-- 
Philippe.

Re: [Xenomai-core] Make watchdog-timer configurable

[Philippe Gerum]

On Tue, 2007-09-04 at 15:12 +0200, Johan Borkhuis wrote:
> I made the following change to Xenomai (version 2.3.2, but it could also 
> be applied to 2.4 as the watchdog code has not been changed).
> 

Merged, with forward port to 2.4. Thanks.

> The watchdog timeout is fixed at 4 seconds. For us this is a problem as 
> there are some processes that take more time than this.
> 
> I made the following change to allow this to be changed through the 
> Linux kernel configuration. The value is configurable between 1 and 60 
> seconds.
> 
> Below is a patchfile that implements this change. Please let me know if 
> you have comments on this, or if there are problems with this change.
> 
> ================
> diff -u -r org/xenomai-2.3.2/ksrc/nucleus/Kconfig 
> xenomai-2.3.2/ksrc/nucleus/Kconfig
> --- org/xenomai-2.3.2/ksrc/nucleus/Kconfig      2007-07-06 
> 18:42:14.000000000 +0200
> +++ xenomai-2.3.2/ksrc/nucleus/Kconfig  2007-09-04 14:13:41.000000000 +0200
> @@ -172,6 +172,17 @@
>         behalf of the timer tick handler, thus is only active after
>         the timer has been started.
>  
> +config XENO_OPT_WATCHDOG_PERIOD
> +       depends on XENO_OPT_WATCHDOG
> +       int "Watchdog period (s)"
> +       default 4
> +    range 1 60
> +       help
> +
> +    Nr of seconds of uninterrupted real-time activity after which
> +    the watchdog triggers.
> +
> +
>  menu "Timing"
>  
>  config XENO_OPT_TIMING_PERIODIC
> diff -u -r org/xenomai-2.3.2/ksrc/nucleus/pod.c 
> xenomai-2.3.2/ksrc/nucleus/pod.c
> --- org/xenomai-2.3.2/ksrc/nucleus/pod.c        2007-07-07 
> 10:18:57.000000000 +0200
> +++ xenomai-2.3.2/ksrc/nucleus/pod.c    2007-09-04 14:06:35.000000000 +0200
> @@ -2925,7 +2925,7 @@
>         return nkpod->svctable.faulthandler(fltinfo);
>  }
>  
> -#ifdef CONFIG_XENO_OPT_WATCHDOG
> +#if (defined CONFIG_XENO_OPT_WATCHDOG) && 
> (CONFIG_XENO_OPT_WATCHDOG_PERIOD > 0)
>  
>  /*!
>   * @internal
> @@ -2948,7 +2948,7 @@
>                 return;
>         }
>  
> -       if (unlikely(++sched->wd_count >= 4)) {
> +       if (unlikely(++sched->wd_count >= 
> CONFIG_XENO_OPT_WATCHDOG_PERIOD)) {
>                 xnltt_log_event(xeno_ev_watchdog, thread->name);
>                 xnprintf("watchdog triggered -- killing runaway thread 
> '%s'\n",
>                          thread->name);
> 
> ================
> 
> Kind regards,
>     Johan Borkhuis
> 
> 
> _______________________________________________
> Xenomai-core mailing list
> Xenomai-core@domain.hid
> https://mail.gna.org/listinfo/xenomai-core
-- 
Philippe.