cpufreq: interactive: Add a sampling_down_factor for max frequencies

Change min_sample_time to 100ms when running at max

Change-Id: Ia7e35b0625bedf20e7ef3a1f52e5828ffbfed93e
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Allow 1 ms error in above_hispeed_delay comparisons

Allow for an error of 1 ms while taking into account
above_hispeed_delay for a frequency

Change-Id: I744e44387152e4efb5978df4f2b9533bf79d4582
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: sync freq feature for interactive governor

1) Add load info to cpufreq_interactive_cpuinfo
2) If load on any other online cpu exceeds sync_freq_load_threshold,
   do not allow the frequency to drop below sync_freq

Change-Id: I3617e10f87b85178914a18bcf04ac2a31a4f1ec1
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>

Conflicts:
	drivers/cpufreq/cpufreq_interactive.c
cpufreq: interactive: Reset floor_validate_time if busy at max for 100ms

When the interactive governor selects to run at max frequency it doesn't
re-schedule the timer until it hits an idle. This change checks if the CPU
has been continuously busy for last 100ms on hitting an idle start. If yes,
then floor_validate_time is reset so that the CPU stays at max frequency
for at least another 100 ms before stepping down.
This is an important feature for detecting CPU intensive workloads which
require high frequencies for achieving better performance.

Change-Id: I7d48ffbc3d50a80af9be3bf94667ee3d0120b763
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Remove trace event from idle_start handler

Removed the trace_cpufreq_interactive_idle_start.
Also fix a crash resulting from accessing NULL policy before taking
the pcpu->enable_sem lock. The policy can be NULL if the core is
hotplugged out before the enable_sem lock is taken.

Change-Id: I7e2809cc016b3b383a44cdf3c697013e2d2b5417
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Modifying sync_freq implementation

1. Check for up_threshold_any_cpu_freq instead of sync_freq to
   boost the frequency to sync_freq.
2. Change the load threshold name from sync_freq_load_threshold to
   up_threshold_any_cpu_load
3. Do not consider CPUs with load less than up_threshold_any_cpu_load
   while evaluating max load across CPUs

Change-Id: Ia0e537edbf38a5006c1a22f5c472daa0d086ffc9
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Use default min_sample_time if SDF is zero

Use min_sample_time to step down from max frequencies if
sampling_down_factor is set to zero.

Change-Id: I2e89bef6220557cb95efd20d658e0c05753b4c3c
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Fix null pointer dereference in interactive governor

For the sync_freq feature currently we check pcpu->policy->cur frequency
for each online cpu.  But for a CPU that isn't using interactive governor
or for an offline CPU, pcpu->policy can be null or an invalid value.
This patch tries to avoid that scenario by using pcpu->target_freq
instead of policy->cur to get the frequency of an online CPU.

Kernel crash without this patch:
[   20.132373] Unable to handle kernel NULL pointer dereference at virtual address 00000028
[   20.132375] pgd = c34f34c0
[   20.132377] pgd = ef6f2440
[   20.132383] [00000028] *pgd=00000000
[   20.132385]
[   20.132388] [00000028] *pgd=2e98f003, *pmd=00000000
[   20.132390] Internal error: Oops: 205 [#1] PREEMPT SMP ARM
[   20.132394] Modules linked in:
[   20.132398] CPU: 0 PID: 1560 Comm: chown Tainted: G        W    3.10.0-perf-gb12057b-00001-ga2c6c16-dirty #7
[   20.132401] task: ef9af300 ti: ee49c000 task.ti: ee49c000
[   20.132411] PC is at cpufreq_interactive_timer+0x10c/0x650
[   20.132415] LR is at cpufreq_interactive_timer+0x128/0x650
<snip>
[   20.133002] [<c07eb204>] (cpufreq_interactive_timer+0x10c/0x650) from [<c02804d8>] (call_timer_fn+0x80/0x198)
[   20.133012] [<c02804d8>] (call_timer_fn+0x80/0x198) from [<c0280acc>] (run_timer_softirq+0x1f8/0x270)
[   20.133019] [<c0280acc>] (run_timer_softirq+0x1f8/0x270) from [<c0279e20>] (__do_softirq+0x12c/0x2d4)
[   20.133025] [<c0279e20>] (__do_softirq+0x12c/0x2d4) from [<c027a2d4>] (irq_exit+0x74/0xc8)
[   20.133034] [<c027a2d4>] (irq_exit+0x74/0xc8) from [<c0206a00>] (handle_IRQ+0x68/0x8c)
[   20.133041] [<c0206a00>] (handle_IRQ+0x68/0x8c) from [<c02004b8>] (gic_handle_irq+0x3c/0x60)
[   20.133051] [<c02004b8>] (gic_handle_irq+0x3c/0x60) from [<c0ac6900>] (__irq_svc+0x40/0x70)
<snip>

Change-Id: Ie834f5d383de4d41e0fe6fbd40c8b0a0c05d82f5
Signed-off-by: Vijay Ganti <viganti@codeaurora.org>
cpufreq: interactive: delete timers for GOV_START

Make sure that timers cpu_timer and cpu_slack_timer
deactivated before addition of new.

Change-Id: If31c4049606871df6f00efdc24b1d713c86a6f69
Signed-off-by: Shridhar Rasal <srasal@nvidia.com>
Signed-off-by: Bharat Nihalani <bnihalani@nvidia.com>
Git-commit: b430123367e78a6557bac3cf1558bcb85193fb12
Git-repo: https://android.googlesource.com/kernel/common/
[mattw@codeaurora.org: resolved trivial context conflict]
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
cpufreq: Add cpu-boost driver

When certain bursty and important events take place, it might take a while
for the current cpufreq governor to notice the new load and react to it.
That would result in poor user experience. To alleviate this, the cpu-boost
driver boosts the frequency of a CPU for a short duration to maintain good
user experience while the governor catches up.

Specifically, this commit deals with ensuring that when "important" tasks
migrate from a fast CPU to a slow CPU, the frequency of the slow CPU is
boosted to be at least as high as the fast CPU for a short duration.

Since this driver enforces the boost by hooking into standard cpufreq
ADJUST notifiers, it has several advantages:
- More portable across kernel versions where the cpufreq internals might
  have been rewritten.
- Governor agnostic and hence works with multiple governors like
  conservative, ondemand, interactive, etc.
- Does not affect the sampling period/logic of existing governors.
- Can have the boost period adjusted independent of governor sampling
  period.

Change-Id: Ibd814a20043d0aba64ee7637a4a79b9ffa1b0991
Signed-off-by: Saravana Kannan <skannan@codeaurora.org>
cpufreq: Add a sync limit to cpu-boost

Perform frequency synchronization only when source CPU's frequency
is less than sync_threshold, else sync to the sync_threshold.

Change-Id: I544c414568d4e015b80ce5891dd215275bac95da
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: Add Input Boost feature to the cpu-boost driver

On incoming input events boost the frequency of all online cpus
for at least input_boost_ms ms. This is accomplished by changing
the policy->min of all the online cpus to input_boost_freq.

Change-Id: Idb0ab75d68ae4ceff259cbbaaec1a9bb3bc871d3
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: Disable cpu-boost by default

Disable cpu-boost by default, so that it can be turned ON only by
setting the module parameter boost_ms through command prompt when
required.

Change-Id: Ia9bc280892f65ed1d2e8051d1951e51922ad13db
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: cpu-boost: Use hotplug thread infrastructure

Before this patch, thread migration ran in uninterruptible threads.
Use the relatively new hotplug thread infrastructure with parked
threads to reduce cpu load (x4).

Change-Id: I4fa1f3a6d6b2b68ecb6e751678584f24abd85992
cpufreq: cpu-boost: Fix queue_delayed_work_on() race with hotplug

Calling queue_delayed_work_on() on a CPU that's in the process of getting
hotplugged out can result in that CPU infinitely looping in
msm_pm_wait_cpu_shutdown(). If queue_delayed_work_on() is called after the
CPU is hotplugged out, it could wake up the CPU without going through the
hotplug path and cause instability. To avoid this, make sure the CPU is and
stays online while queuing a work on it.

Signed-off-by: Saravana Kannan <skannan@codeaurora.org>

Conflicts:
	drivers/cpufreq/cpu-boost.c

Change-Id: I35bc30380f253bce39db22ad59af9258803e9735
cpufreq: cpu-boost: Remove unused waitqueue

Change-Id: I2e72d8ee5f2777bffe8d7817122934d8857c78b6
cpufreq: Sync on thread migration optimizations

When threads migrate between CPUs the destination CPU will temporarily
have a boosted frequency and the source CPU will have a residual higher
frequency even though the load could have just been reduced. To avoid
leaving CPUs at a high frequencies notify the source CPU after a thread
migration and make the interactive governor's timer reschedule
conditionally.

Change-Id: Id55055f2a116ca7ffd2a34dc3d0ec519c888a111
Signed-off-by: Patrick Cain <pcain@codeaurora.org>
cpufreq: interactive: Don't reset sampling down factor at max freq

A previous patch sets the min_sample_time to zero if the cpufreq
min/max limits have changed which would bring down the frequency
in the next sample even if min_sample_time doesnt allow it to do so.
This could severly affect benchmarks if this is applied to max
frequencies as min_sample_time for max frequencies is set to
sampling_down_factor.
This patch resets the limits_changed flag for cases where timer fires
while running at max frequencies so that sampling_down_factor is
still applicable as before.

Change-Id: I397133cb15eea4ab999d0f69617b4922438c6e11
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: interactive: Remove unnecessary cpu_online() check

Cpufreq no longer calls governor callback for offlined cpus. i.e. All
policy->cpus are guaranteed to be online. Hence we don't need explicit check to
see if cpu is online or not.

Change-Id: I9ad85ea4addd5b4a40952e59ed730dd15e328690
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
cpufreq: interactive: Optimize sync_freq implementation

Don't let frequency drop below sync_freq if either load or
frequency among other cpus is above a certain threshold,
not necessarily both.

Change-Id: Iada28e08e812498e16d5189b309a7314f88814dd