writeback: I believe these defines were calculated with HZ=1000 in mi…

…nd. Since our devices are HZ=100 I hardcoded the values on this
constants. I'm not 100% sure if this code was made for HZ with 1000 but
I couldn't track it to understand clearly. Although I didn't see any
drawback of using this as it is now. If anyone knows the answer please
chime in.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
writeback: fix writeback cache thrashing

From: Namjae Jeon <namjae.jeon@samsung.com>

Consider Process A: huge I/O on sda
        doing heavy write operation - dirty memory becomes more
        than dirty_background_ratio
        on HDD - flusher thread flush-8:0

Consider Process B: small I/O on sdb
        doing while [1]; read 1024K + rewrite 1024K + sleep 2sec
        on Flash device - flusher thread flush-8:16

As Process A is a heavy dirtier, dirty memory becomes more
than dirty_background_thresh. Due to this, below check becomes
true(checking global_page_state in over_bground_thresh)
for all bdi devices(even for very small dirtied bdi - sdb):

In this case, even small cached data on 'sdb' is forced to flush
and writeback cache thrashing happens.

When we added debug prints inside above 'if' condition and ran
above Process A(heavy dirtier on bdi with flush-8:0) and
Process B(1024K frequent read/rewrite on bdi with flush-8:16)
we got below prints:

[Test setup: ARM dual core CPU, 512 MB RAM]

[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  56064 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  56704 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 84720 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 94720 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   384 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   960 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =    64 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 92160 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   256 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   768 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =    64 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   256 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   320 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =     0 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 92032 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 91968 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   192 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =  1024 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =    64 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   192 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   576 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =     0 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 84352 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   192 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =   512 KB
[over_bground_thresh]: wakeup flush-8:16 : BDI_RECLAIMABLE =     0 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 92608 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE = 92544 KB

As mentioned in above log, when global dirty memory > global
background_thresh
small cached data is also forced to flush by flush-8:16.
If removing global background_thresh checking code, we can reduce cache
thrashing of frequently used small data.
And It will be great if we can reserve a portion of writeback cache
using
min_ratio.

After applying patch:
$ echo 5 > /sys/block/sdb/bdi/min_ratio
$ cat /sys/block/sdb/bdi/min_ratio
5
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  56064 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  56704 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  84160 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  96960 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  94080 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  93120 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  93120 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  91520 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  89600 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  93696 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  93696 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  72960 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  90624 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  90624 KB
[over_bground_thresh]: wakeup flush-8:0 : BDI_RECLAIMABLE =  90688 KB

As mentioned in the above logs, once cache is reserved for Process B,
and patch is applied there is less writeback cache thrashing on sdb
by frequent forced writeback by flush-8:16 in over_bground_thresh.

After all, small cached data will be flushed by periodic writeback
once every dirty_writeback_interval.

Suggested-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>

The original code has been modified to compile on this Kernel version.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
wakelock: remove deprecated create_singlethread_workqueue and replace…

… with the modern alloc_workqueue.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Lower voltage for gpu
writeback: I believe these defines were calculated with HZ=1000 in mind.
Since our devices are HZ=100 I hardcoded the values on this constants.
I'm not 100% sure if this code was made for HZ with 1000 but I couldn't
track it to understand clearly. Although I didn't see any drawback of
using this as it is now. If anyone knows the answer please chime in.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
removed 51mhz and 102mhz for tf201 devices (BETA)
min freq to 204mhz to avoid sod's
video memory remap from new tf300t sources

/**
 * vm_iomap_memory - remap memory to userspace
 * @vma: user vma to map to
 * @start: start of area
 * @len: size of area
 *
 * This is a simplified io_remap_pfn_range() for common driver use. The
 * driver just needs to give us the physical memory range to be mapped,
 * we'll figure out the rest from the vma information.
 *
 * NOTE! Some drivers might want to tweak vma->vm_page_prot first to get
 * whatever write-combining details or similar.
 */
attempt to fix the discharging dock issue
new config v3.3.4
Added exfat-nofuse driver
added http://www.tuxera.com/community/ntfs-3g-download/

to build for arm open a cmd and go to:

/fs/ntfs-3g_ntfsprogs

enter: sh build_for_arm.sh
EXFAT 1.2.5
rt_config interface for runnable threads hotplugging and some changed
parameters
CPU_WAKE_FREQ_LOW fix
suspend index fix, added 51 and 102MHz back
lp_core uv and removed user_mv_table because its not needed anymore
because i changed the cpu_uv if
tf300t new kernel source merge
added gpu uv interface and changed cpu uv interface
interactive tuning