Re: ondemand governor and passive cooling broken?

[Thomas Renninger <mail@renninger.de>]

Hi,

This makes ondemand governor aware of thermal limits.
The policy was buffered and new policy values never reached the governor.

I just used the cpufreq_get_policy call every time the load is checked,
maybe the new policy should be made available via notifier as it is done
for the cur_freq in the userspace governor?
If this sounds reasonable I can come up with a bigger patch on Monday.

However, thermal cooling still does not always work right:

  - Sometimes the limit is not decreased correctly in polling frequency time
    (I saw it at max for more than 20 secs, polling freq 5 secs, passive tp exceeded).
    Strange enough, that seems to happen only in rare cases.
  - I also saw the limit stuck at lowest frequency even after getting back in
    normal temperature zones.
  - And once you entered passive cooling you always see the "cooling: passive"
    flag set in /proc/acpi/thermal_zone/*/cooling_mode


    Thomas


--- drivers/cpufreq/cpufreq_ondemand.c.orig     2005-08-20 19:26:18.000000000 -0600
+++ drivers/cpufreq/cpufreq_ondemand.c  2005-08-20 19:28:04.000000000 -0600
@@ -254,6 +254,10 @@
        if (!this_dbs_info->enable)
                return;

+       int ret = cpufreq_get_policy(this_dbs_info->cur_policy, cpu);
+       if (ret)
+               return;
+
        policy = this_dbs_info->cur_policy;
        /*
         * Every sampling_rate, we check, if current idle time is less