mm/swap: fix race on swap_info reuse between swapoff and swapon
DateThu, 09 Jan 2014 13:39:55 +0800

swapoff clear swap_info's SWP_USED flag prematurely and free its resources
after that. A concurrent swapon will reuse this swap_info while its previous
resources are not cleared completely.

These late freed resources are:
- p->percpu_cluster
- swap_cgroup_ctrl[type]
- block_device setting
- inode->i_flags &= ~S_SWAPFILE

This patch clear SWP_USED flag after all its resources freed, so that swapon
can reuse this swap_info by alloc_swap_info() safely.

Change-Id: I64609c8a1d266dac812eb81e73f3bb338a97290f
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Signed-off-by: Paul Reioux <reioux@gmail.com>
f2fs: call mark_inode_dirty to flush dirty pages

If a dentry page is updated, we should call mark_inode_dirty to add the inode
into the dirty list, so that its dentry pages are flushed to the disk.
Otherwise, the inode can be evicted without flush.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: move a branch for code redability

This patch moves a function in f2fs_delete_entry for code readability.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: add help function META_MAPPING

Introduce help function META_MAPPING() to get the cache meta blocks'
address space.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: remove the orphan block page array

As the orphan_blocks may be max to 504, so it is not security
and rigorous to store such a large array in the kernel stack
as Dan Carpenter said.
In fact, grab_meta_page has locked the page in the page cache,
and we can use find_get_page() to fetch the page safely in the
downstream, so we can remove the page array directly.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: introduce NODE_MAPPING for code consistency

This patch adds NODE_MAPPING which is similar as META_MAPPING introduced by
Gu Zheng.

Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
f2fs: drop obsolete node page when it is truncated

If a node page is trucated, we'd better drop the page in the node_inode's page
cache for better memory footprint.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
drivers/cpufreq: Update Zzmove to v0.7d (Dual Core Mode)
fs/f2fs: Add Missing REQ_PRIO defines
block: Add a new REQ_PRIO, f2fs quick hack

Taken from Christoph Hellwig <hch@infradead.org> patch
block: separate priority boosting from REQ_META
drivers/cpufreq: Updated Zzmoove to Version 0.8 - cool down baby

Changelog:

- indroduced scaling block cycles (in normal and legacy mode) to reduce unwanted jumps to higher frequencies (how high depends on settings)
  when a load comes up just for a short peroid of time or is hitting the scaling up threshold more often because it is within some higher
  to mid load range. reducing these jumps lowers CPU temperature in general and may also save some juice. so with this function u can influence
  the little bit odd scaling behaving when you are running apps like for example games which are constantly 'holding' system load in
  some range and the freq is scaled up too high for that range. in fact it just looks like so, monitoring apps are mostly too slow to catch load in
  realtime so you are watching almost only 'the past'. so actually it's not really odd it's more like: an app is stressing the system and holding
  it on a higher load level, due to this load level scaling up threshold is more often reached (even if monitoring shows a lower load
  than up_threshold) the governor scales up very fast (usual zzmoove behaving) and almost never scales down again (even if monitoring shows
  a lower load than down_threshold). now in patricular these scaling block cycles are throttling up scaling by just skipping it
  for the amount of cycles that you have set up and after that are making a forced scale down in addition for the same amount of cycles. this
  should bring us down to a 'appropriate' frequency when load is hanging around near up threshold.
- indroduced (D)ynamic (S)ampling (R)ate - thx to hellsgod for having the same idea at the same time and pointing me to an example. even though
  at the end i did 'my way' :) DSR switches between two sampling rates depending on the given load threshold from an 'idle' to a 'normal' one.
- added read only tuneable 'sampling_rate_current' for DSR to show current SR and internally use this sampling rate instead of automatically
  changing 'sampling_rate' tuneable in DSR. this keeps things more compatible and avoids problems when governor tuneables are set with tuning
  apps which are saving actual shown values.
- changed setting of sampling rate in governor from 'sampling_rate' to 'sampling_rate_current' and the value at suspend to 'sampling_rate_idle'
  value instead of using current active sampling rate to avoid accidentally setting of 'normal operation' sampling rate in sampling rate idle mode
  which has usually a much lower value
- indroduced build-in profiles in seperate header file (credits to Yank555 for idea and prototype header file)
  you can switch between multible build in profiles by just piping a number into the tuneable 'profile_number'. all tuneable values of the set
  profile will be applied on-the-fly then. if a profile is active and you change any tuneable value from it to a custom one the profile will
  switch to '0' in 'profile_number' and 'custom' in 'profile' for information. with this profiles support developers can simplify their governor
  settings handling by adding all their desired and well proven governor settings into the governor itself instead of having to fiddle around with
  init.d scripts or tuning apps. NOTE: this is just an optional feature, you can still set all tuneables as usual just pay attention that the
  tuneable 'profile_number' is set to '0' then to avoid overwriting values by any build-in profile. for further details about profiles and
  adding own ones check provided 'cpufreq_zzmoove_profiles.h' file.
- added 'profiles_version' tuneable to be able to show seperate profiles header file version
- added enabling of offline cores on governor exit to avoid cores 'stucking' in offline state when switching to a non-hotplug-able governor
  and by the way reduced reduntant code by using an inline function for switching cores on and using the better 'sheduled_work_on-way'
  at all needed places in the code for that purpose
- moved some code parts to legacy mode macro which has only relevance when including the legacy mode in the governor and in addition
  excluded it during runtime if legacy mode is disabled.
- improved freq limit handling in tuneables and in dbs_check_cpu function
- changed value restriction from '11' to '1' in hotplug down threshold and grad up tuneables as this restriction is only nessesary in
  scaling down tuneable
- added missing fast scaling down/normal scaling up mode to fast scaling functionality (value range 9-12 and only available in non-legacy mode
  thx OldBoy.Gr for pointing me to that missing mode)
- added auto fast scaling aka 'insane' scaling mode to fast scaling functionality - lucky number 13 enables this mode in fast_scaling tuneable
  NOTE: a really funny mode, try it :) but keep in mind setting this in combination with a set freq limit (at sleep or awake)would not make much
  sense as there is not enough frequency range available to jump around then.
- back from the precautious 'mutex_try_lock' to normal 'mutex_lock' in governor 'LIMIT' case -> this should be save again,
  no deadlocks expected any more since hotplug logic has significantly changed in zzmoove version 0.6
- removed also the no longer required and precautious skipping of hotplugging and dbs_check_cpu on multiple places in code and removed
  the mutex locks at governor stop and early suspend/late resume
- added hotlug freq thresholds to legacy scaling mode (same usage as in normal scaling mode)
- seperated hotplug down and up block cycles to be more flexible. this replaces 'hotplug_block_cycles' with 'hotplug_block_up_cycles' tuneable
  and adds one new tunable 'hotplug_block_down_cycles'. functionality is the same as before but u can now differentiate the up and down value.
- added 'early demand sleep' combined with automatic fast scaling (fixed to scaling up mode 2) and if not set already automatic
  (depending on load) switching of sampling rate sleep multiplier to a fixed minimum possible multiplier of 2.
  this should avoid mostly audio or general device connection problems with 'resource hungrier' apps like some music players,
  skype, navigation apps etc. and/or in combination with using bluetooth equipment during screen is off.
  NOTE: this overwrites a possible fast 'scaling_sleep' setting so use either this or 'fast_scaling_sleep'
- added some missing governor tunebable default value definitions
- removed tuneable apply order exception and removed analog value checks in hotplug threshold and hotplug frequency tuneables to avoid
  tuneable values not changing issues. NOTE: keep in mind that all 'down' values should be lower then the analog 'up' values and vice versa.
- removed 200 mhz up hotplugging restriction, so up hotplugging starts at 200 mhz now
- removed some unnecessary macros in scaling logic
- added maximum fast scaling and frequency boost to late resume to react wakeup lags
- merged some improvements from ktoonservativeq governor version for the SGS4 (credits to ktoonsez)
  changes from here: https://github.com/ktoonsez/KT-SGS4/commits/aosp4.4/drivers/cpufreq/cpufreq_ktoonservativeq.c
  Use dedicated high-priority workqueues
  Use NEW high-priority workqueue for hotplugging
  Improved hotplugging in general by reducing calls to plugging functions if they are currently running,
  by reducing calls to external function in up plugging and by changing the down plug loop to an optimized one
- added hotplug boost switch to early demand functionality and up hotplugging function
- added 'hotplug_idle_freq' tuneable to be able to adjust at which frequency idle should begin
- transfered code for frequency table order detection and limit optimisation into a inline function
  and use this function in START,LIMIT case and early suspend/late resume instead of using redundant code
- execute table order detection and freq limit optimization calculations at 'START' and 'LIMIT' case to avoid possible wrong setting of freq
  max after governor start (currently set max frequency value was sometimes not applied) and a wrong soft limit optimization setting
  after undercutting the soft limit with a lower hard limit value
- minor optimisation in hotplug, hotplug block and in all freq search logic parts
- added debugging sysfs interface (can be included/excluded using #define ZZMOOVE_DEBUG) - credits to Yank555
- added some missing annotation as a prepareation and mainly to avoid some errors when compiling zzmoove in combination with 3.4+ kernel sources
- fixed hotplugging issues when cpufreq limit was set under one or more hotplugging frequency thresholds
  NOTE: now hotplugging frequency thresholds will be completely disabled and a fall back to normal load thresholds will happen
  if the maximal possible frequency will undercut any frequency thresholds
- fixed wrong setting of sampling rate idle when early demand sleep was off
  (under some circumstances this led to sampling rate = 0 = a full stop in the governor, oops *g*)
- fixed stopping of up scaling at 100% load when up threshold tuneable is set to the max value of 100
- fixed smooth up not active at 100% load when smooth up tuneable is set to the max value of 100
- fixed many code style and dokumentation issues and made a massive code re-arrangement

for this functions following new tuneables were indroduced:

early_demand_sleep              -> same function as early demand on awake but in addition combined with fast scaling and sampling rate
                                   switch and only active at sleep. (possible values 0 disable or 1 enable, default is 1)
grad_up_threshold_sleep         -> 2 way functionality: early demand sleep grad up (load gradient) threshold and at the same time load threshold
                                   for switching internally (tuneables are staying at set values) sampling_rate_sleep_multiplier to 2 and
                                   fast_scaling to 2 (possible values from 1 to 100, default is 35)
hotplug_block_up_cycles         -> (replaces hotplug_block_cycles) slow down up hotplugging by waiting a given amount of cycles before plugging.
                                   possible values 0 disbale, any values above 0 (default is 0)
hotplug_block_down_cycles       -> (replaces hotplug_block_cycles) slow down down hotplugging by waiting a given amount of cycles before plugging.
                                   possible values 0 disbale, any values above 0 (default is 0)
hotplug_idle_freq               -> freq at which the idle should be active (possible values 0 disable and any possible scaling freq, default is 0)
sampling_rate_current           -> read only and shows currently active sampling rate
sampling_rate_idle              -> sampling rate which should be used at 'idle times'
                                   (possible values are any sampling rate > 'min_sampling_rate', 0 to disable whole function, default is 0)
sampling_rate_idle_delay        -> delay in cycles for switching from idle to normal sampling rate and vice versa
                                   (possible values are any value and 0 to disable delay, default is 0)
sampling_rate_idle_threshold    -> threshold under which idle sampling rate should be active
                                   (possible values 1 to 100, 0 to disable function, default is 0)
scaling_block_cycles            -> amount of gradients which should be counted (if block threshold is set) and at the same time up scaling should be
                                   blocked and after that a forced down scaling should happen (possible values are any value, 0 to disable that
                                   function, default is 0)
scaling_bock_freq               -> frequency at and above the blocking should be active
                                   (possible values are any possible scaling freq, 0 to enable blocking permanently at every frequency, default is 0)
scaling_block_threshold         -> gradient (min value) of load in both directions (up/down) to count-up cycles
                                   (possible value are 1 to 100, 0 to disable gradient counting)
scaling_block_force_down        -> multiplicator for the maximal amount of forced down scaling cycles (force down cycles = block_cycles * force_down)
                                   therefore the forced down scaling duration (possible value are 2 to any value, 0 to disable forced down scaling
                                   and use only scaling up blocks)
profile                         -> read only and shows name of currently active profile ('none' = no profile, 'custom' = a profile value has changed)
profile_number                  -> switches profile (possible value depends on amount of profiles in cpufreq_zzmoove_profiles.h file,
                                   please check this file for futher details) 0 no profile set = tuneable mode, default 0)
version_profiles                -> read only and shows version of profile header file

if ZZMOOVE_DEBUG is defined:
debug                           -> read only and shows various usefull debugging infos
timekeeping: Fix time moving backwards

Changed the calculation logic that sometimes calculates
the time wrong.

Sometimes there is an overflow when the tv_nsec field in
the timespec structure is being added since it is 32-bit.

To resolve this issue nsec variable is being added first
so that the addition is performed in 64 bit signed format.

Bug 1217429

Change-Id: I9c65da88f02596ba73c47be6342ed909e650db22
Signed-off-by: Ajay Nandakumar <anandakumarm@nvidia.com>
Reviewed-on: http://git-master/r/195092
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Reviewed-by: Shridhar Rasal <srasal@nvidia.com>
Reviewed-by: Bo Yan <byan@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Tested-by: Shridhar Rasal <srasal@nvidia.com>
cpufreq: zzmoove v0.8 - fix settings for yank profiles
LMK update from I9300 OSRC update 13
Add F2FS driver to kernel
Tweak android logger memory
Fix Fsync merge
 lib/int_sqrt.c: optimize square root algorithm

Signed-off-by: flar2 <asegaert@gmail.com>

Fix a madvise merge
Update kernel power driver
Add export header