Android LNK: reduced protected apps / services from Kill to release RAM.

Services are auto start again FRESH without leaking RAM.

so let LNK kill them in case there is no more free RAM!

Also removed minfree_screen_on setting as it's not needed.

On screen OFF, kernel copy lowmem_minfree to lowmem_minfree_screen_on
and then set the lowmem_minfree_screen_off to lowmem_minfree

so when screen will be ON lowmem_minfree_screen_on will push data
to lowmem_minfree table!
Android LMK: Updated with more info about task killed + function mods!

Also impoved skip task kill function to allow kill protected task
if it's reach 100Mb ram usage!
staging: android: lowmemorykiller: select a new task to kill

Under certain circumstances, a process may take time to handle a SIGKILL.
When lowmemkiller is called again shortly after, it would pick the same
process to kill over and over, so that we cann't get free memory for long time.

Solution is to check fatal_signal_pending() on the selected task, and if it's
already pending, select a new task to kill.

Cherry-pick 5e3358093351e5d48e21250e31896b855542f22c
Reviewed-on: http://gerrit.pcs.mot.com/479831

Change-Id: I53445114451ffaba293f3c7174fb0b01ed0d34b6
Signed-off-by: Tianshui Shi <kfp634@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/505410
Tested-by: Jira Key <JIRAKEY@motorola.com>
Reviewed-by: Yi-Wei Zhao <gbjc64@motorola.com>
Reviewed-by: Jason Hrycay <jason.hrycay@motorola.com>
Reviewed-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
(cherry picked from commit da093001caf06ed2296b4f79c84cc48ce713eac6)
trace: memkill: trace LMK and OOM kills

How to enable tracer:

  # mount -t debugfs nodev /sys/kernel/debug
  # echo 1 > /sys/kernel/debug/tracing/tracing_on
  # echo 1 > /sys/kernel/debug/tracing/events/memkill/enable
  # cat /sys/kernel/debug/tracing/trace

Event format:

  oom_kill: <pid> <comm> <total_vm> <anon_rss> <file_rss> <oom_score_adj> <order> <points> <cached> <freeswap>
  oom_kill_shared: <pid> <comm>
  lmk_kill: <pid> <comm> <selected_oom_adj> <selected_tasksize> <min_adj> <cached> <freeswap>

Change-Id: Ic45e181c62aead9b19d2a40363217f9220896096
Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/480746
Reviewed-on: http://gerrit.pcs.mot.com/513174
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Jason Hrycay <jason.hrycay@motorola.com>
Reviewed-by: Klocwork kwcheck <klocwork-kwcheck@sourceforge.mot.com>
Reviewed-by: Thirumarai Selvi S <a16462@motorola.com>
Reviewed-by: Check Patch <CHEKPACH@motorola.com>
Reviewed-by: Christopher Fries <qcf001@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
(cherry picked from commit ef733ddfbb73cd33daf36720fa474ce4c8acb1f7)
trace: allow memkill tracing to be selectively enabled

Change-Id: I8a50d6b121192b0dc94e2a9a0e05246a47045e81
Signed-off-by: Jeffrey Carlyle <jeff.carlyle@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/482673
Reviewed-on: http://gerrit.pcs.mot.com/513906
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Klocwork kwcheck <klocwork-kwcheck@sourceforge.mot.com>
Reviewed-by: Thirumarai Selvi S <a16462@motorola.com>
Reviewed-by: Check Patch <CHEKPACH@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
(cherry picked from commit fd9bd32cd8f005b0d2f6438935fdd0bc9654c938)
staging: android: lowmemorykiller: implement task's adj rbtree

Based on the current LMK implementation, LMK has to scan all processes to
select the correct task to kill during low memory.
The basic idea for the optimization is to :
queue all tasks with oom_score_adj priority, and then LMK just selects the
proper task from the queue(rbtree) to kill.

performance improvement:
the current implementation: average time to find a task to kill : 1004us
the optimized implementation: average time to find a task to kill: 43us

Change-Id: I4dbbdd5673314dbbdabb71c3eff0dc229ce4ea91
Signed-off-by: Hong-Mei Li <a21834@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/548917
SLT-Approved: Slta Waiver <sltawvr@motorola.com>
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Yi-Wei Zhao <gbjc64@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
staging: android: lmk: check free memory when tasks switch to background

Add more free-memory check point.
This patch trigger low memory killer to scan free memory when a process is moved
to background task groups.

Change-Id: If50eef2fb2c05f57ab808f95a9408204058f4f9b
Signed-off-by: Hong-Mei Li <a21834@motorola.com>
Reviewed-on: http://gerrit.pcs.mot.com/557973
Tested-by: Jira Key <jirakey@motorola.com>
Reviewed-by: Yi-Wei Zhao <gbjc64@motorola.com>
SLTApproved: Yi-Wei Zhao <gbjc64@motorola.com>
Submit-Approved: Jira Key <jirakey@motorola.com>
LMK: more clean implementation of ANDROID_LMK_ADJ_RBTREE

when i merge new code i need to know every new mod that added to code!

this tweak to LMK is not exist in main line code.
page_alloc: Make watermarks tunable separately

This patch introduces three new sysctls to /proc/sys/vm:
wmark_min_kbytes, wmark_low_kbytes and wmark_high_kbytes.

Each entry is used to compute watermark[min], watermark[low]
and watermark[high] for each zone.

These parameters are also updated when min_free_kbytes are
changed because originally they are set based on min_free_kbytes.
On the other hand, min_free_kbytes is updated when wmark_free_kbytes
changes.

By using the parameters one can adjust the difference among
watermark[min], watermark[low] and watermark[high] and as a result
one can tune the kernel reclaim behaviour to fit their requirement.

Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>

modified and tuned for Hammerhead

Signed-off-by: Paul Reioux <reioux@gmail.com>
Merged part of LMK from my I9100 Kernel.
Added missing OOM control file. for OOM set on screen ON
Android LMK: Updated with more info about task killed + function mods!

Also impoved skip task kill function to allow kill protected task
if it's reach 100Mb ram usage!