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From here: http://www.xenomai.org/documentation/xenomai-2.6/TROUBLESHOOTING

Q: Which CONFIG_* items are latency killers, and should be avoided ?
APM: The APM model assigns power management control to the BIOS, and BIOS code is never written with RT-latency in mind. If configured, APM routines are invoked with SMI priority, which breaks the rule that adeos-ipipe must be in charge of such things. DISABLE_SMI doesnt help here (more later).

The problem is that I am not able to find this APM thing anywhere.

enter image description here

enter image description here

"ACPI (Advanced Configuration and Power Interface) Support" results in the following menu:

 --- ACPI (Advanced Configuration and Power Interface) Support
[*]   Deprecated /proc/acpi files
[*]   Deprecated power /proc/acpi directories
 <M>   ACPI 4.0 power meter
 < >   EC read/write access through /sys/kernel/debug/ec (NEW)
[*]   Deprecated /proc/acpi/event support
<M>   AC Adapter
<M>   Battery
{M}   Button
{M}   Video
<M>   Fan
[*]   Dock
<M>   Processor
< >   IPMI (NEW)
<M>   Processor Aggregator
<M>   Thermal Zone
-*-   NUMA support
()    Custom DSDT
Table file to include
[*]   Debug Statements
[ ]   Additionally enable ACPI function tracing
<M>   PCI slot detection driver
{M}   Container and Module Devices (EXPERIMENTAL)
<M>   Memory Hotplug
<M>   Smart Battery System
< >   Hardware Error Device (NEW)
[ ]   ACPI Platform Error Interface (APEI) (NEW)

Please help.

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up vote 3 down vote accepted

You can find this option yourself:

Press / in the menu menuconfig interface , and put CONFIG_APM there , if you find anything , it's supported

I can only give you output from 3.3.7 version:

enter image description here

But anyway , you could edit the .config file yourself , and append CONFIG_APM=y , then redo make menuconfig ,

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Actually, I am missing some point here. I am using "make menuconfig". That shows a GUI. This option isn't there in "Power management and ACPI support". I did attach the screenshot. what am I over looking? – TheIndependentAquarius Jun 1 '12 at 8:28
@AnishaKaul if you're running this kernel already , can you show the output of zgrep APM /proc/config.gz – warl0ck Jun 1 '12 at 8:35
I am not running this kernel yet. I have to configure this first. :) I am kind of stuck here. :( – TheIndependentAquarius Jun 1 '12 at 8:41
@AnishaKaul what about grep APM .config (inside kernel folder , provided you've saved your config) – warl0ck Jun 1 '12 at 8:45
I ran the command like this, didn't say anything: linux-y3pi:/usr/src/linux- # grep APM .config – TheIndependentAquarius Jun 1 '12 at 8:46

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