]> git.karo-electronics.de Git - linux-beck.git/commit
powernv/cpuidle: Redesign idle states management
authorShreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Tue, 9 Dec 2014 18:56:52 +0000 (00:26 +0530)
committerMichael Ellerman <mpe@ellerman.id.au>
Sun, 14 Dec 2014 23:46:40 +0000 (10:46 +1100)
commit7cba160ad789a3ad7e68b92bf20eaad6ed171f80
treeef57d54fcf61e5acf912e03004c0913457d3832b
parent8eb8ac89a364305d05ad16be983b7890eb462cc3
powernv/cpuidle: Redesign idle states management

Deep idle states like sleep and winkle are per core idle states. A core
enters these states only when all the threads enter either the
particular idle state or a deeper one. There are tasks like fastsleep
hardware bug workaround and hypervisor core state save which have to be
done only by the last thread of the core entering deep idle state and
similarly tasks like timebase resync, hypervisor core register restore
that have to be done only by the first thread waking up from these
state.

The current idle state management does not have a way to distinguish the
first/last thread of the core waking/entering idle states. Tasks like
timebase resync are done for all the threads. This is not only is
suboptimal, but can cause functionality issues when subcores and kvm is
involved.

This patch adds the necessary infrastructure to track idle states of
threads in a per-core structure. It uses this info to perform tasks like
fastsleep workaround and timebase resync only once per core.

Signed-off-by: Shreyas B. Prabhu <shreyas@linux.vnet.ibm.com>
Originally-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: linux-pm@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/cpuidle.h [new file with mode: 0644]
arch/powerpc/include/asm/opal.h
arch/powerpc/include/asm/paca.h
arch/powerpc/include/asm/processor.h
arch/powerpc/kernel/asm-offsets.c
arch/powerpc/kernel/exceptions-64s.S
arch/powerpc/kernel/idle_power7.S
arch/powerpc/platforms/powernv/opal-wrappers.S
arch/powerpc/platforms/powernv/setup.c
arch/powerpc/platforms/powernv/smp.c
drivers/cpuidle/cpuidle-powernv.c