cpufreq: ondemand: Boost CPU frequency only for touch input

Originally CPU frequency were boosted for any input event.
In some case, sensor sends a lot of input event, which
keep CPU in high frequency.  CPU frequency only need to
be boosted when real user interaction happens.

Change-Id: Ia3ad755b98d8363a17729926610b5dd6f0075288
CR-Fixed: 507519
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
cpufreq: ondemand: Fix update_sampling_rate race with hotplug

update_sampling_rate has a for loop which goes through each
online cpu and possibly queue up the ondemand work for them.
But while doing this it doesnt take any hotplug lock which
could potentially cause a race condition where ondemand work
is queued after the hotplug code (which sets the policy to NULL)
in the governor has cancelled any pending work. This could cause
a crash while trying to access the NULL policy in dbs_check_cpu.

Protecting the for_each_online_cpu loop with get_online_cpus()
and put_online_cpus().

Change-Id: Ia3f43ca7e4bed542834ab03ca1191d728f13311c
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
cpufreq: ondemand: Fix hotplug deadlock with store_powersave_bias

store_powersave_bias() acquires the hotplug lock and the dbs_mutex
lock, but does so in the wrong order.  Deadlocks like the following
can result.

Thread A:
    get_online_cpus+0x3c/0x5c           <- acquires 'cpu_hotplug.lock'
    store_powersave_bias+0x80/0x3f4     <- acquires 'dbs_mutex'
    kobj_attr_store+0x14/0x20
    sysfs_write_file+0x108/0x13c
    vfs_write+0xb0/0x128
    sys_write+0x38/0x64

Thread B:
    cpufreq_governor_dbs+0x7c/0x55c     <- acquires 'dbs_mutex'
    __cpufreq_governor+0x90/0xe0
    __cpufreq_set_policy+0x1b0/0x258
    cpufreq_add_dev_interface+0x2cc/0x334
    cpufreq_add_dev+0x514/0x580
    cpufreq_cpu_callback+0x88/0x9c
    notifier_call_chain+0x38/0x68
    __cpu_notify+0x28/0x40
    _cpu_up+0xe4/0x118                  <- acquires 'cpu_hotplug.lock'
    cpu_up+0x64/0x80
    store_online+0x48/0x78
    dev_attr_store+0x18/0x24
    sysfs_write_file+0x108/0x13c
    vfs_write+0xb0/0x128
    sys_write+0x38/0x64

Fix this by flipping the order in which the locks are acquired and
released in store_powersave_bias so that it is the same as in the
hotplug path.

Change-Id: Idc59fb29d60b8f7fceb8ed0f2bb9eff4670abda7
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
cpufreq: ondemand: add input_boost interface

Currently Ondemand governor handles any input event
like touch by scaling the CPU frequency to maximum
available on the target.

This change adds a new sysfs interface "input_boost"
whereby the CPU will scale to this frequency on input events.
The value of this sysfs is user defined so input events
can now be handled by scaling the CPU to lower frequencies
than target max.

Change-Id: I5428fd8797c9984b17a66b01a44557f2160e8b68
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: allow arbitrary speed / delay mappings

Accept a string of delays and speeds at which to apply the delay before
raising each step above hispeed. For example, "80000 1300000:200000
1500000:40000" means that the delay at or above 1GHz, until 1.3GHz is 80 msecs,
the delay until 1.5GHz is 200 msecs and the delay at or above 1.5GHz is 40
msecs when hispeed_freq is 1GHz.

[toddpoynor@google.com: add documentation]
Change-Id: Ifeebede8b1acbdd0a53e5c6916bccbf764dc854f
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Git-commit: e43dde3b6cec1e1d36a477713bcfb1dda070bef2
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: add io_is_busy interface

Previously the idle time returned from get_cpu_idle_time_us included the
iowait time. So the iowait time was always calculated as idle time.

But now the idle time returned from get_cpu_idle_time_us does not include
the iowait time anymore because of below commit which cause the iowait time
always calculated as busy time:
    6beea0c nohz: Fix update_ts_time_stat idle accounting

Add the io_is_busy interface, as does the ondemand governor, and let the user
configure the iowait time as busy or idle through the io_is_busy sysfs
interface.

By default, io_is_busy is disabled.

[toddpoynor@google.com: minor updates]
Change-Id: If7d70ff864c43bc9c8d7fd7cfc66f930d339f9b4
Signed-off-by: Lianwei Wang <lian-wei.wang@motorola.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Git-commit: fbcad7234e0aef2725d9f33ac5a0c3a9cc61a9ac
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: fix crash on error paths in get_tokenized_data

Use separate variable for error code, free proper pointer.

Change-Id: Ia83cccb195997789ac6afbf5b8761f7b278196d6
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Git-commit: cad1684410541be5363d4af9ae8f3f35683a4dd4
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: base above_hispeed_delay on target freq, not current

Time to wait should be based on the intended target speed, not the
actual speed (which may be held high by another CPU).

Change-Id: Ifc5bb55d06adddb9a02af90af05398a78f282272
Reported-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Git-commit: c4483b5550079c46dbc68005920a14f371d3f4eb
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: fix uninitialized spinlock

Add missing spinlock init

Backtrace:
[<c0011ce4>] (dump_backtrace+0x0/0x10c) from [<c0662a68>] (dump_stack+0x18/0x1c)
 r6:00000032 r5:c0bd09ec r4:e6848000 r3:00000000
[<c0662a50>] (dump_stack+0x0/0x1c) from [<c06670b0>] (spin_dump+0x80/0x94)
[<c0667030>] (spin_dump+0x0/0x94) from [<c06670f0>] (spin_bug+0x2c/0x30)
 r5:c08f91fc r4:c0bd09ec
[<c06670c4>] (spin_bug+0x0/0x30) from [<c0245f74>] (do_raw_spin_unlock+0x88/0xcc)
 r5:e547bac0 r4:c0bd09ec
[<c0245eec>] (do_raw_spin_unlock+0x0/0xcc) from [<c066c9cc>] (_raw_spin_unlock_irqrestore+0x14/0x40)
 r5:e547bac0 r4:60000013
[<c066c9b8>] (_raw_spin_unlock_irqrestore+0x0/0x40) from [<c044b884>] (store_above_hispeed_delay+0x6c/0x80)
 r4:c0b4cf78 r3:00000007
[<c044b818>] (store_above_hispeed_delay+0x0/0x80) from [<c0235d24>] (kobj_attr_store+0x1c/0x28)
 r7:e68ff000 r6:00000032 r5:e58137c0 r4:e61cde80
[<c0235d08>] (kobj_attr_store+0x0/0x28) from [<c0156b78>] (sysfs_write_file+0x104/0x184)
[<c0156a74>] (sysfs_write_file+0x0/0x184) from [<c0100680>] (vfs_write+0xb0/0x140)
[<c01005d0>] (vfs_write+0x0/0x140) from [<c0100900>] (sys_write+0x44/0x70)
 r8:00000000 r7:00000004 r6:00000032 r5:bee43c90 r4:e5600300
[<c01008bc>] (sys_write+0x0/0x70) from [<c000e400>] (ret_fast_syscall+0x0/0x30)
 r9:e6842000 r8:c000e584 r6:00000032 r5:bee43c90 r4:00000009

Change-Id: I80a1e0b3fecb24adba501ff44f568479deeff7fa
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Git-commit: 2e745d359ffaa9f4acc4b00950d14322ff364919
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: handle errors from cpufreq_frequency_table_target

Add checks for error return from cpufreq_frequency_table_target, and be
less noisy on the existing call with an error check.  CPU hotplug and
system shutdown may cause this call to return -EINVAL.

Bug: 8613560
Change-Id: Id78d8829920462c0db1c7e14e717d91740d6cb44
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Git-commit: 952c6d49444061849e2e254b0d701ebb1664f4b3
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: reduce chance of zero time delta on load eval

Reschedule load sampling timer after timestamp of sample start taken,
hold spinlock across entire sequence to avoid preemption.  Avoid the
WARN for zero time delta in the load sampling timer function.

Change-Id: Idc10a756f09141decb6df92669521a1ebf0dbc10
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Git-commit: 20075d8e9d42aac6e248c7cbe6a2f8a0a00d4ba4
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: avoid underflow on active time calculation

Check for idle time delta less than elapsed time delta, avoid
underflow computing active time.

Change-Id: I3e4c6ef1ad794eec49ed379c0c50fa727fd6ad28
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Git-commit: 3022f93a1aff25b3c9174ac659d7e4a143892267
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: fix race on cpufreq TRANSITION notifier

The cpufreq TRANSTION notifier callback does not check the
governor_enabled state on affected CPUS, which will case
kernel panic in update_load because the policy object maybe
NULL or invalid when governor_enabled is false.

Change-Id: Ie0f1718124f61e2f9b5da57abc6981ada5b83908
Signed-off-by: Lianwei Wang <a22439@motorola.com>
Git-commit: 44011f4524e86ca5a5e90bb941499cbe37a21987
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: resched timer if max freq raised

When the policy max freq is raised, and before the timer is
rescheduled in idle callback, the cpu freq may stuck at a
lower freq.

The target_freq shall be updated too, else on a high load
situation, the new_freq is always equal to target_freq and
which will cause freq stuck at a lower freq too.

Reschedule the timer on gov limits callback.

Change-Id: I6c187001ab43e859731429b64f75a74eebc37a24
Signed-off-by: Lianwei Wang <a22439@motorola.com>
Git-commit: 0edc2b4c9c30a695d9500d3204acdf5f3ddfa027
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
cpufreq: interactive: fix show_target_loads and show_above_hispeed_delay

Remove a trailing whitespace from target_loads and above_hispeed_delay. Problem
happens when user-space program tried to restore parameters that saved before
changing parameters. In this case was returned error(EINVAL).

Change-Id: I5a74e3824602cd6f2b74651adda5ec1b627e61e9
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Git-commit: e116c66cdee9080bf8ecb35c2179d79bd00c3043
Git-repo: https://android.googlesource.com/kernel/common/
Signed-off-by: Dilip Gudlur <dgudlur@codeaurora.org>
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: 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>