[PATCH 0/2] Quiet power limit notification
From: Fenghua Yu
Date: Wed May 15 2013 - 16:44:12 EST
From: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Power Limit Notification (X86_FEATURE_PLN) was added in Sandy Bridge
to give the OS the option of knowing when the package has reached
a configured power threshold.
Linux-2.6.36 enabled this feature:
0199114c31798af5b83841b21759b64171060d9b
(x86, hwmon: Package Level Thermal/Power: power limit)
It enabld the interrupt, and the interrupt hander
added to the MCE log and printed to the console:
printk(KERN_CRIT "CPU%d: %s power limit notification (total events = %lu)
printk(KERN_INFO "CPU%d: %s power limit normal\n"
However, these events are quite routine on some systems under some conditions,
alarming customers and provoking un-necessary customer support calls.
So the MCE log entry was deleted in Linux-3.3:
29e9bf1841e4f9df13b4992a716fece7087dd237
(x86, mce, therm_throt: Don't report power limit and package level thermal throttle events in mcelog)
Here we delete the corresponding kernel console messages,
and then we disable the interrupt by default -- allowing it
to be enabled by cmdline for diagnosis purposes.
https://bugzilla.kernel.org/show_bug.cgi?id=36182
This pair of patches applies cleanly back to Linux-3.3.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/