Intelli_plug (squashed)
sched: Make scheduler aware of cpu frequency state
Capacity of a cpu (how much performance it can deliver) is partly
determined by its frequency (P) state, both current frequency as well
as max frequency it can reach.  Knowing frequency state of cpus will
help scheduler optimize various functions such as tracking every
task's cpu demand and placing tasks on various cpus.

This patch has scheduler registering for cpufreq notifications to
become aware of cpu's frequency state. Subsequent patches will make
use of derived information for various purposes, such as task's scaled
load (cpu demand) accounting and task placement.

Change-Id: I376dffa1e7f3f47d0496cd7e6ef8b5642ab79016
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
sched: window-based load stats for tasks

Provide a metric per task that specifies how cpu bound a task is. Task
execution is monitored over several time windows and the fraction of
the window for which task was found to be executing or wanting to run
is recorded as task's demand. Windows over which task was sleeping are
ignored. We track last 5 recent windows for every task and the maximum
demand seen in any of the previous 5 windows (where task had some
activity) drives freq demand for every task.

A per-cpu metric (rq->cumulative_runnable_avg) is also provided which
is an aggregation of cpu demand of all tasks currently enqueued on it.
rq->cumulative_runnable_avg will be useful to know if cpu frequency
will need to be changed to match task demand.

Change-Id: Ib83207b9ba8683cd3304ee8a2290695c34f08fe2
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
sysctl: add cold_boot sysctl entry

Add a cold_boot parameter which supplements the
boot_reason sysctl entry with information about
whether the system was booted from cold or warm state.

/proc/sys/kernel/cold_boot entry is updated with 1 or 0 when
system was booted from cold or warm boot state respecitively.

CRs-Fixed: 461256
Change-Id: I2bc5d80c8f26eb9e9dbb4b34960d991a51a224e4
Signed-off-by: David Keitel <dkeitel@codeaurora.org>
cpufreq: cpu-boost: Introduce scheduler assisted load based syncs
Previously, on getting a migration notification cpu-boost changed
the scaling min of the destination frequency to match that of the
source frequency or sync_threshold whichever was minimum.

If the scheduler migration notification is extended with task load
(cpu demand) information, the cpu boost driver can use this load to
compute a suitable frequency for the migrating task. The required
frequency for the task is calculated by taking the load percentage
of the max frequency and no sync is performed if the load is less
than a particular value (migration_load_threshold).This change is
beneficial for both perf and power as demand of a task is taken into
consideration while making cpufreq decisions and unnecessary syncs
for lightweight tasks are avoided.

The task load information provided by scheduler comes from a
window-based load collection mechanism which also normalizes the
load collected by the scheduler to the max possible frequency
across all CPUs.

Change-Id: Id2ba91cc4139c90602557f9b3801fb06b3c38992
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: cpu-boost: Handle wakeup hints received for foreground tasks

A previous change modifies the notification conditions in the scheduler
to call the notifier chain even on foreground_thread wakeups for tasks
having load more than a threshold value.

If load_based_syncs is turned OFF then we do not need to perform
cpu boost for wakeup hints for foreground tasks from scheduler

Change-Id: Ifbdd3eccac5c9892dfc3a3c3edbfc0df766478ed
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
sched: Disable wakeup hints for foreground tasks by default

By default sched_wakeup_load_threshold is set to 60 and therefore
wakeup hints are sent out for those tasks whose loads are higher
that value. This might cause unnecessary wakeup boosts to happen
when load based syncing is turned ON for cpu-boost.
Disable the wake up hints by setting the sched_wakeup_load_threshold
to a value higher than 100 so that wakeup boost doesnt happen unless
it is explicitly turned ON from adb shell.

Change-Id: I9b8a594c2bfdf2e092cc645e50c0c21efc514c2f
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
sched: Window-based load stat improvements

Some tasks can have a sporadic load pattern such that they can suddenly
start running for longer intervals of time after running for shorter
durations. To recognize such sharp increase in tasks' demands, max
between the average of 5 window load samples and the most recent sample
is chosen as the task demand.

Make the window size (sched_ravg_window) configurable at boot up
time. To prevent users from setting inappropriate values for window
size, min and max limits are defined. As 'ravg' struct tracks load for
both real-time and non real-time tasks it is moved out of sched_entity
struct.

In order to prevent changing function signatures for move_tasks() and
move_one_task() per-cpu variables are defined to track the total load
moved. In case multiple tasks are selected to migrate in one load
balance operation, loads > 100 could be sent through migration notifiers.
Prevent this scenario by setting mnd.load to 100 in such cases.

Define wrapper functions to compute cpu demands for tasks and to change
rq->cumulative_runnable_avg.

Change-Id: I9abfbf3b5fe23ae615a6acd3db9580cfdeb515b4
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
context_tracking: New context tracking susbsystem

Create a new subsystem that probes on kernel boundaries
to keep track of the transitions between level contexts
with two basic initial contexts: user or kernel.

This is an abstraction of some RCU code that use such tracking
to implement its userspace extended quiescent state.

We need to pull this up from RCU into this new level of indirection
because this tracking is also going to be used to implement an "on
demand" generic virtual cputime accounting. A necessary step to
shutdown the tick while still accounting the cputime.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[ paulmck: fix whitespace error and email address. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Conflicts:
	kernel/sched/core.c
	kernel/sched/fair.c
sched: add PF_WAKE_UP_IDLE
Certain workloads may benefit from the SD_SHARE_PKG_RESOURCES behavior
of waking their tasks up on idle CPUs. The feature has too much of a
negative impact on other workloads however to apply globally. The
PF_WAKE_UP_IDLE flag tells the scheduler to wake up tasks that have this
flag set, or tasks woken by tasks with this flag set, on an idle CPU
if one is available.

Change-Id: I20b28faf35029f9395e9d9f5ddd57ce2de795039
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
sched: add sysctl for controlling task migrations on wake

The PF_WAKE_UP_IDLE per-task flag made it impossible to enable
the old behavior of SD_SHARE_PKG_RESOURCES, where every task
migrates to an idle CPU on wakeup.

The sched_wake_to_idle sysctl value, when made nonzero, will cause
all tasks to migrate to an idle CPU if one is available when the
task is woken up. This is regardless of how PF_WAKE_UP_IDLE is
configured for tasks in the system. Similar to PF_WAKE_UP_IDLE,
the SD_SHARE_PKG_RESOURCES scheduler domain flag must be enabled
for the sysctl value to have an effect.

Change-Id: I23bed846d26502c7aed600bfcf1c13053a7e5f61
Signed-off-by: Steve Muckle <smuckle@codeaurora.org>
(cherry picked from commit 9d5b38dc0025d19df5b756b16024b4269e73f282)

Conflicts:

	kernel/sched/fair.c
add extra free kbytes tunable

Add a userspace visible knob to tell the VM to keep an extra amount
of memory free, by increasing the gap between each zone's min and
low watermarks.

This is useful for realtime applications that call system
calls and have a bound on the number of allocations that happen
in any short time period.  In this application, extra_free_kbytes
would be left at an amount equal to or larger than than the
maximum number of allocations that happen in any burst.

It may also be useful to reduce the memory use of virtual
machines (temporarily?), in a way that does not cause memory
fragmentation like ballooning does.

[ccross]
Revived for use on old kernels where no other solution exists.
The tunable will be removed on kernels that do better at avoiding
direct reclaim.

Change-Id: I765a42be8e964bfd3e2886d1ca85a29d60c3bb3e
Signed-off-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Colin Cross <ccross@android.com>
Git-commit: 92189d47f66c67e5fd92eafaa287e153197a454f
Git-repo: https://android.googlesource.com/kernel/common/
[bhargavuln@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Bhargav Upperla <bhargavuln@codeaurora.org>
cpufreq: cpu-boost: Export cpu boost status

* This will help hotplug drivers to know boost status
  of CPU and act accordingly.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
update cpu-boost driver
context_tracking: New context tracking susbsystem
Create a new subsystem that probes on kernel boundaries
to keep track of the transitions between level contexts
with two basic initial contexts: user or kernel.

This is an abstraction of some RCU code that use such tracking
to implement its userspace extended quiescent state.

We need to pull this up from RCU into this new level of indirection
because this tracking is also going to be used to implement an "on
demand" generic virtual cputime accounting. A necessary step to
shutdown the tick while still accounting the cputime.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[ paulmck: fix whitespace error and email address. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
add extra free kbytes tunable

Add a userspace visible knob to tell the VM to keep an extra amount
of memory free, by increasing the gap between each zone's min and
low watermarks.

This is useful for realtime applications that call system
calls and have a bound on the number of allocations that happen
in any short time period.  In this application, extra_free_kbytes
would be left at an amount equal to or larger than than the
maximum number of allocations that happen in any burst.

It may also be useful to reduce the memory use of virtual
machines (temporarily?), in a way that does not cause memory
fragmentation like ballooning does.

[ccross]
Revived for use on old kernels where no other solution exists.
The tunable will be removed on kernels that do better at avoiding
direct reclaim.

Change-Id: I765a42be8e964bfd3e2886d1ca85a29d60c3bb3e
Signed-off-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Colin Cross <ccross@android.com>
Git-commit: 92189d47f66c67e5fd92eafaa287e153197a454f
Git-repo: https://android.googlesource.com/kernel/common/
[bhargavuln@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Bhargav Upperla <bhargavuln@codeaurora.org>
msm_sleeper (squashed)
Signed-off-by: flar2 <asegaert@gmail.com>
Add hyper CPU governor
cpufreq: cpu-boost: Export wakeup_boost

* This is needed to unify boost functions in cpu boost
  and hotplug drivers.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
intelli_plug: Use wakeup_boost hint

* In current scenario, we boost (turn all cores online)
  whenever LCD turns on. This is really not required when
  we have good hotplug mechanism in place. The mechanism
  should detect load and put appropriate cpus online.
* Boosting CPUs each time will increase battery consumption
  (maybe not so much but we should prevent this)
* So boost CPUs and apply downlock only in two cases viz.
  hotplug was suspended and user requested wakeup_boost
  via cpu-boost driver from userspace.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
intelli_plug: Fixes for suspend/resume work rare issues

* It is observed that suspend_defer_time is not
  working as required. It should suspend as soon as defer
  time is completed. Therefore, make use of separate freezable
  workqueue to do this smoothly.
* Organize sequence for initiating and cancelling work.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
intelli_plug: Initiate suspend defer time with default value

* Thanks to @Dorimanx for notifying.

Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>