wip: intellidemand tweaks
intellidemand patch up
defconfig stuff
cpufreq: Add cpu utilization statistics to aid decisions made by userspace.

Understanding system load as seen by cpufreq can help userspace
algorithms make better decisions to improve system responsiveness.
One such example would be the MP decision algorithm which mines
various system info to make decisions on hotplugging in/out
the additional cores.

Change-Id: I277db7e1a7803a3822b61e7befa25131487cfe17
Signed-off-by: Anitha Anand <anithas@codeaurora.org>
sched: track the runnable average on a per-task entitiy basis

From: Paul Turner <pjt@google.com>

Instead of tracking averaging the load parented by a cfs_rq, we can track
entity load directly.  With the load for a given cfs_rq then being the sum of
its children.

To do this we represent the historical contribution to runnable average within each
trailing 1024us of execution as the coefficients of a geometric series.

We can express this for a given task t as:
  runnable_sum(t) = \Sum u_i * y^i, runnable_avg_period(t) = \Sum 1024 * y^i
  load(t) = weight_t * runnable_sum(t) / runnable_avg_period(t)

Where: u_i is the usage in the last i`th 1024us period (approximately 1ms) ~ms
and y is chosen such that y^k = 1/2.  We currently choose k to be 32 which
roughly translates to about a sched period.

Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
backported to Linux 3.0.x by faux123 from Linux 3.5+
sched: maintain per-rq runnable averages

From: Ben Segall <bsegall@google.com>

Since runqueues do not have a corresponding sched_entity we instead embed a
sched_avg structure directly.

Signed-off-by: Ben Segall <bsegall@google.com>
Reviewed-by: Paul Turner <pjt@google.com>
backported from Linux 3.5+ to Linux 3.0 by faux123

Conflicts:
	kernel/sched_fair.c
sched: aggregate load contributed by task entities on parenting cfs_rq

From: Paul Turner <pjt@google.com>

For a given task t, we can compute its contribution to load as:
  task_load(t) = runnable_avg(t) * weight(t)

On a parenting cfs_rq we can then aggregate
  runnable_load(cfs_rq) = \Sum task_load(t), for all runnable children t

Maintain this bottom up, with task entities adding their contributed load to
the parenting cfs_rq sum.  When a task entity's load changes we add the same
delta to the maintained sum.

Signed-off-by: Paul Turner <pjt@google.com>
Reviewed-by: Ben Segall <bsegall@google.com>
backported by faux123 for Linux 3.0 kernel from Linux 3.5+