powerpc/pseries/cpuidle: smt-snooze-delay cleanup.
authorDeepthi Dharwar <deepthi@linux.vnet.ibm.com>
Tue, 14 Jan 2014 10:56:38 +0000 (16:26 +0530)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Wed, 29 Jan 2014 06:02:24 +0000 (17:02 +1100)
commit3fa8cad82b94d0bed002571bd246f2299ffc876b
tree3c85c1da6f6d78a8f96348df0e4d23a38256ebe9
parentbf7f61f2dfc5c5764e862bee317a5a227091d0d2
powerpc/pseries/cpuidle: smt-snooze-delay cleanup.

smt-snooze-delay was designed to disable NAP state or delay the entry
to the NAP state prior to adoption of cpuidle framework. This
is per-cpu variable. With the coming of CPUIDLE framework,
states can be disabled on per-cpu basis using the cpuidle/enable
sysfs entry.

Also, with the coming of cpuidle driver each state's target residency
is per-driver unlike earlier which was per-device. Therefore,
the per-cpu sysfs smt-snooze-delay which decides the target residency
of the idle state on a particular cpu causes more confusion to the user
as we cannot have different smt-snooze-delay (target residency)
values for each cpu.

In the current code, smt-snooze-delay functionality is completely broken.
It makes sense to remove smt-snooze-delay from idle driver with the
coming of cpuidle framework.
However, sysfs files are retained as ppc64_util currently
utilises it. Once we fix ppc64_util, propose to clean
up the kernel code.

Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/include/asm/processor.h
arch/powerpc/kernel/sysfs.c
drivers/cpuidle/cpuidle-pseries.c