cpufreq: interactive: Move definition of cpufreq_gov_interactive downwards

This moves definition of cpufreq_gov_interactive towards the bottom of file, so
that we don't have to add prototype of cpufreq_governor_interactive() in the
beginning of file.

Change-Id: I04bd1004954eb36502c5cd7e35d3d7274cddaf95
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Git-commit: e50d640cacfe61e69f1b4fa92fa0174c688e919c
Git-Repo: https://android.googlesource.com/kernel/common.git
[junjiew@codeaurora.org: Resolve merge conflicts]
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: MassStash <MassStash@gmail.com>

Signed-off-by: MassStash <MassStash@gmail.com>

Conflicts:
	drivers/cpufreq/cpufreq_interactive.c
cpufreq: interactive: merge back stock bacon interactive code to merge the next patches. Will re-apply some of the custom code after the merges.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>

Conflicts:
	drivers/cpufreq/cpufreq_interactive.c
cpufreq: interactive: Squashed cleanup patches

Revert "cpufreq: interactive: Remove unnecessary cpu_online() check"

This reverts commit 7b46e2e6d8a3c3c32706ee3c3c3b507d050bedfb.

Revert "cpufreq: interactive: Allow 1 ms error in above_hispeed_delay comparisons"

This reverts commit ff6af80775231f1dfab8353d0b665718222218bf.

Commit ff6af807 tries to avoid a corner case where frequency is stuck in
hispeed_freq for one additional window. For example, if timer_rate is
20ms, and go_hispeed_delay is 40ms, frequency might be stuck at
hispeed_freq for 60ms due to imprecision in jiffies. Same problem can be
easily solved by making go_hispeed_delay 1ms smaller instead of changing
the code.

Signed-off-by: Junjie Wu <junjiew@codeaurora.org>

cpufreq: interactive: Revert timer start modification

commit f8b276565ce95bd788af0fc8d060f92632590a40
(cpufreq: Sync on thread migration optimizations)
introduced a change to cpufreq_interactive_timer_start() in order
to reschedule the timer differently based on whether min or max
is changed. A better way is to reschedule the timer only when
necessary.

Revert timer start modification in preparation for the final fix.

Signed-off-by: Junjie Wu <junjiew@codeaurora.org>

Revert "cpufreq: interactive: Optimize sync_freq implementation"

This reverts commit 4da7f27d4dbd5bcfb8479467444f2cf198217933.

cpufreq: interactive: Revert sync on thread migration optimizations

Commit f8b276565ce95bd788af0fc8d060f92632590a40
(cpufreq: Sync on thread migration optimizations) is no longer needed
for targets with synchronous CPUs.

Part of that commit has already been reverted in
a913b3afcaa55356f5f793ae895312c8ae7e1f71
(cpufreq: interactive: Revert timer start modification)

This commit reverts the remaining changes.

Signed-off-by: Junjie Wu <junjiew@codeaurora.org>

cpufreq: interactive: Revert sync freq feature

Sync freq feature is not valid for a HMP system with clusters.

This commit reverts commit f3d1980b4db4c20f21acaed59cc511c2df84cec2
(cpufreq: interactive: sync freq feature for interactive governor)

Signed-off-by: Junjie Wu <junjiew@codeaurora.org>

cpufreq: interactive: Remove sampling_down_factor

Remove sampling_down_factor feature.

This commit revert d094d23694edf41fee50ebc544795d6116451643
(cpufreq: interactive: Add a sampling_down_factor for max frequencies)
and subsequent modifications related to sampling down factor.

Signed-off-by: Junjie Wu <junjiew@codeaurora.org>

Conflicts:
	drivers/cpufreq/cpufreq_interactive.c

Change-Id: I9e5fd451e7eaefe8ef7775365cc5a4527d37188f
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>
cpufreq: interactive: Align timer windows for all CPUs

It's more advantageous to evaluate all CPUs at same time so that
interactive governor gets a complete picture of the load on
each CPU at a specific time. It could also reduce number of speed
changes made if there are many CPUs controlled by same policy. In
addition, waking up all CPUs at same time would allow the cluster
to go into a deeper sleep state when it's idle.

Change-Id: I6915050c5339ef1af106eb906ebe4b7c618061e2
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
cpufreq: interactive: Reset last evaluated jiffy in idle callback

When CPU has been busy for a long time, last evaluated jiffy will be
quite behind because the timer would have been canceled. We don't want
to schedule a timer to fire in the past as load will always be 100%.

Reset last evaluated jiffy so that timer will be scheduled for the
next window.

Change-Id: Ie25e65eab1f16acdeda267987ca605d653f1f32a
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
cpufreq: interactive: Round up timer_rate to match jiffy

Timers are scheduled in unit of jiffies. Round up timer_rate so that
it matches the actual sampling period.

Change-Id: I47e666f835752528331f50b1e76784e6d67f8bcf
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
cpufreq: interactive: Use del_timer/add_timer_on to rearm timers

Replace mod_timer_pinned() with del_timer(), add_timer_on().
mod_timer_pinned() always adds timer onto current CPU. Interactive
governor expects each CPU's timers to be running on the same CPU.
If cpufreq_interactive_timer_resched() is called from another CPU,
the timer will be armed on the wrong CPU.

Replacing mod_timer_pinned() with del_timer() and add_timer_on()
guarantees timers are still run on the right CPU even if another
CPU reschedules the timer. This would provide more flexibility
for future changes.

Change-Id: I3a10be37632afc0ea4e0cc9c86323b9783b216b1
Signed-off-by: Junjie Wu <junjiew@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
smp: Add task_struct argument to __cpu_up()

Preparatory patch to make the idle thread allocation for secondary
cpus generic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de

Conflicts:
	arch/arm/kernel/smp.c

Change-Id: Idd1ab4a309918acee2b934fba3de5879663b7fec
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>
arm: Use generic idle thread allocation

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Tested-by: Frank Rowand <frank.rowand@am.sony.com>
Link: http://lkml.kernel.org/r/20120420124557.448826362@linutronix.de

Conflicts:
	arch/arm/Kconfig
	arch/arm/kernel/smp.c

Change-Id: I5d578157a22fc7accd152a4515e4dd2c9b086b75
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>
cpu: Fix generic idle thread allocation

 * This was missed in the backport, rendering it ineffective.

Change-Id: I1cb079531d0dce913ce3693a9557e99f324ad346
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>
cpufreq: interactive: add the hook to get the current load at any point in time.

Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: MassStash <MassStash@gmail.com>
ARM: Introduce arch_read_hardware_id

Moving towards device tree and arm single binary refering to
machine descriptor name for hardware id information under
/proc/cpuinfo is not suitable for certain soc vendors. Add a
hook for soc vendors to supply a per-soc hardware read method.

Change-Id: I8d6f77dbb8037c943d58e0d39fcaa9b54366650e
Signed-off-by: Abhimanyu Kapur <abhimany@codeaurora.org>
ARM: 7680/1: Detect support for SDIV/UDIV from ISAR0 register

The ISAR0 register indicates support for the SDIV and UDIV
instructions in both the Thumb and ARM instruction set. Read the
register to detect the supported instructions and update the
elf_hwcap mask as appropriate. This is better than adding more
and more cpuid checks in proc-v7.S for each new cpu variant that
supports these instructions.

Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
ARM: 7587/1: implement optimized percpu variable access

Use the previously unused TPIDRPRW register to store percpu offsets.
TPIDRPRW is only accessible in PL1, so it can only be used in the kernel.

This replaces 2 loads with a mrc instruction for each percpu variable
access. With hackbench, the performance improvement is 1.4% on Cortex-A9
(highbank). Taking an average of 30 runs of "hackbench -l 1000" yields:

Before: 6.2191
After: 6.1348

Will Deacon reported similar delta on v6 with 11MPCore.

The asm "memory clobber" are needed here to ensure the percpu offset
gets reloaded. Testing by Will found that this would not happen in
__schedule() which is a bit of a special case as preemption is disabled
but the execution can move cores.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Conflicts:
	arch/arm/include/asm/Kbuild
	arch/arm/kernel/smp.c

Change-Id: Ie143b692a5eea090e615e86e22df90f6ecd7fc2c
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>