sched: Skip load update for idle task

Load statistics for idle tasks is not useful in any manner. Skip load
update for such idle tasks.

CRs-Fixed: 665706
Change-Id: If3a908bad7fbb42dcb3d0a1d073a3750cf32fcf9
Signed-off-by: Srivatsa Vaddagiri <vatsa@codeaurora.org>
cpufreq: fix sleeping in atomic context when realloc freq_table for all_time_in_state

Commit (cpufreq: Persist cpufreq time in state data across hotplug)
causes the following call trace to be spit on boot:

BUG: sleeping function called from invalid context at mm/slub.c:936
in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0
CPU: 6 PID: 1 Comm: swapper/0 Not tainted 3.10.9-20140624.172707-eng-gd6c0f69-dirty #50
Backtrace:
[<c0012270>] (dump_backtrace+0x0/0x10c) from [<c001256c>] (show_stack+0x18/0x1c)
 r6:ffff1788 r5:c0c020c0 r4:e609c000 r3:00000000
[<c0012554>] (show_stack+0x0/0x1c) from [<c07a2970>] (dump_stack+0x20/0x28)
[<c07a2950>] (dump_stack+0x0/0x28) from [<c0057678>] (__might_sleep+0x104/0x120)
[<c0057574>] (__might_sleep+0x0/0x120) from [<c00ff000>] (__kmalloc_track_caller+0x144/0x274)
 r6:00000000 r5:e609c000 r4:e6802140
[<c00feebc>] (__kmalloc_track_caller+0x0/0x274) from [<c00da098>] (krealloc+0x58/0xb0)
[<c00da040>] (krealloc+0x0/0xb0) from [<c050266c>] (cpufreq_allstats_create+0x120/0x204)
 r8:e4c4ff00 r7:c0d266b8 r6:0013d620 r5:e4c4e600 r4:00000001
r3:e535d6d0
[<c050254c>] (cpufreq_allstats_create+0x0/0x204) from [<c0502e38>] (cpufreq_stat_notifier_policy+0xb8/0xd0)
[<c0502d80>] (cpufreq_stat_notifier_policy+0x0/0xd0) from [<c00517cc>] (notifier_call_chain+0x4c/0x8c)
 r5:00000000 r4:fffffffe
[<c0051780>] (notifier_call_chain+0x0/0x8c) from [<c00519fc>] (__blocking_notifier_call_chain+0x50/0x68)
 r8:c0cd4d00 r7:00000002 r6:e609dd7c r5:ffffffff r4:c0d25a4c
r3:ffffffff
[<c00519ac>] (__blocking_notifier_call_chain+0x0/0x68) from [<c0051a34>] (blocking_notifier_call_chain+0x20/0x28)
 r7:c0e24f30 r6:00000000 r5:e53e1e00 r4:e609dd7c
[<c0051a14>] (blocking_notifier_call_chain+0x0/0x28) from [<c0500fec>] (__cpufreq_set_policy+0xc0/0x1d0)
[<c0500f2c>] (__cpufreq_set_policy+0x0/0x1d0) from [<c0501308>] (cpufreq_add_dev_interface+0x20c/0x270)
 r7:00000008 r6:00000000 r5:e53e1e00 r4:e53e1e58
[<c05010fc>] (cpufreq_add_dev_interface+0x0/0x270) from [<c05016a8>] (cpufreq_add_dev+0x33c/0x420)
[<c050136c>] (cpufreq_add_dev+0x0/0x420) from [<c03604a4>] (subsys_interface_register+0x80/0xbc)
[<c0360424>] (subsys_interface_register+0x0/0xbc) from [<c050035c>] (cpufreq_register_driver+0x8c/0x194)

Change-Id: If77a656d0ea60a8fc4083283d104509fa6c07f8f
Signed-off-by: Minsung Kim <ms925.kim@samsung.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
net: wireless: Increase scan entry expiration to fit new scan time

Change-Id: I0e23ce45d78d7c17633670973f49943a5ed6032d
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
cfg80211: ignore supported rates for nonexistant bands on scan

Fixes wpa_supplicant p2p_find on 5GHz-only devices

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-commit: 1b09cd82d8c479700ef6185665839d1020b02519
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Change-Id: Icadd03bfff17c5fd8da3e15e7b69b42a730e0ef0
Signed-off-by: Ahmad Kholaif <akholaif@codeaurora.org>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
sched/cpuidle: reduce IPI store. Backport upstream 3.16 scheduler updates

Signed-off-by: Paul Reioux <reioux@gmail.com>
lz4: ensure length does not wrap

Given some pathologically compressed data, lz4 could possibly decide to
wrap a few internal variables, causing unknown things to happen.  Catch
this before the wrapping happens and abort the decompression.

Reported-by: "Don A. Bailey" <donb@securitymouse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
lz4: fix another possible overrun

There is one other possible overrun in the lz4 code as implemented by
Linux at this point in time (which differs from the upstream lz4
codebase, but will get synced at in a future kernel release.)  As
pointed out by Don, we also need to check the overflow in the data
itself.

While we are at it, replace the odd error return value with just a
"simple" -1 value as the return value is never used for anything other
than a basic "did this work or not" check.

Reported-by: "Don A. Bailey" <donb@securitymouse.com>
Reported-by: Willy Tarreau <w@1wt.eu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
GPU Simple Governor: adapt GPU Simple Governor for Snapdrgaon 800 SOCs

initial coding for a Simple GPU governor based on my own work 2 years ago
from Sensation GB kernel commit: c1ea8f6

Signed-off-by: Paul Reioux <reioux@gmail.com>
Simple GPU governor: fix a merge derp

Signed-off-by: Paul Reioux <reioux@gmail.com>
defconfig: enable GPU simple governor
lib/memcopy: use glibc version

the kernel's memcpy and memmove is very inefficient. But the glibc version is
quite fast, in some cases it is 10 times faster than the kernel version. So I
introduce some memory copy macros and functions of the glibc to improve the
kernel version's performance.

The strategy of the memory functions is:
1. Copy bytes until the destination pointer is aligned.
2. Copy words in unrolled loops.  If the source and destination are not
   aligned in the same way, use word memory operations, but shift and merge
   two read words before writing.
3. Copy the few remaining bytes.

Signed-off-by: Miao Xie <miaox*******>
Signed-off-by: faux123 <reioux@gmail.com>
lib/string: use glibc version

the performance of memcpy and memmove of the general version is very
inefficient, this patch improved them.

Signed-off-by: Miao Xie <miaox*******>
Signed-off-by: faux123 <reioux@gmail.com>
arm/crypto: Add optimized AES and SHA1 routines

Add assembler versions of AES and SHA1 for ARM platforms.  This has provided
up to a 50% improvement in IPsec/TCP throughout for tunnels using AES128/SHA1.

Platform   CPU SPeed    Endian   Before (bps)   After (bps)   Improvement

IXP425      533 MHz      big     11217042        15566294        ~38%
KS8695      166 MHz     little    3828549         5795373        ~51%

Signed-off-by: David McCullough <ucdevel@gmail.com>
Signed-off-by: faux123 <reioux@gmail.com>
defconfig: enable optimized AES and SHA1 routines
Optimized ARM RWSEM algorithm

RWSEM implementation for ARM using atomic functions.
Heavily based on arch/sh/include/asm/rwsem.h

Signed-off-by: Ashwin Chaugule <ashwinc@codeaurora.org>
defconfig: enable ARM RWSEM algorithm
lib/int_sqrt.c: optimize square root algorithm

Optimize the current version of the shift-and-subtract (hardware)
algorithm, described by John von Newmann[1] and Guy L Steele.

Iterating 1,000,000 times, perf shows for the current version:

 Performance counter stats for './sqrt-curr' (10 runs):

         27.170996 task-clock                #    0.979 CPUs utilized            ( +-  3.19% )
                 3 context-switches          #    0.103 K/sec                    ( +-  4.76% )
                 0 cpu-migrations            #    0.004 K/sec                    ( +-100.00% )
               104 page-faults               #    0.004 M/sec                    ( +-  0.16% )
        64,921,199 cycles                    #    2.389 GHz                      ( +-  0.03% )
        28,967,789 stalled-cycles-frontend   #   44.62% frontend cycles idle     ( +-  0.18% )
   <not supported> stalled-cycles-backend
       104,502,623 instructions              #    1.61  insns per cycle
                                             #    0.28  stalled cycles per insn  ( +-  0.00% )
        34,088,368 branches                  # 1254.587 M/sec                    ( +-  0.00% )
             4,901 branch-misses             #    0.01% of all branches          ( +-  1.32% )

       0.027763015 seconds time elapsed                                          ( +-  3.22% )

And for the new version:

Performance counter stats for './sqrt-new' (10 runs):

          0.496869 task-clock                #    0.519 CPUs utilized            ( +-  2.38% )
                 0 context-switches          #    0.000 K/sec
                 0 cpu-migrations            #    0.403 K/sec                    ( +-100.00% )
               104 page-faults               #    0.209 M/sec                    ( +-  0.15% )
           590,760 cycles                    #    1.189 GHz                      ( +-  2.35% )
           395,053 stalled-cycles-frontend   #   66.87% frontend cycles idle     ( +-  3.67% )
   <not supported> stalled-cycles-backend
           398,963 instructions              #    0.68  insns per cycle
                                             #    0.99  stalled cycles per insn  ( +-  0.39% )
            70,228 branches                  #  141.341 M/sec                    ( +-  0.36% )
             3,364 branch-misses             #    4.79% of all branches          ( +-  5.45% )

       0.000957440 seconds time elapsed                                          ( +-  2.42% )

Furthermore, this saves space in instruction text:

   text    data     bss     dec     hex filename
    111       0       0     111      6f lib/int_sqrt-baseline.o
     89       0       0      89      59 lib/int_sqrt.o

[1] http://en.wikipedia.org/wiki/First_Draft_of_a_Report_on_the_EDVAC

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Reviewed-by: Jonathan Gonzalez <jgonzlez@linets.cl>
Tested-by: Jonathan Gonzalez <jgonzlez@linets.cl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
ARM: be strict about FP exceptions in kernel mode

The support code in vfp_support_entry does not care whether the
exception that caused it to be invoked occurred in kernel mode or
in user mode. However, neither condition that could trigger this
exception (lazy restore and VFP bounce to support code) is
currently allowable in kernel mode.

In either case, print a message describing the condition before
letting the undefined instruction handler run its course and trigger
an oops.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
Acked-by: Nicolas Pitre <nico at linaro.org>
Signed-off-by: Paul Reioux <reioux@gmail.com>
ARM: add support for kernel mode NEON

In order to safely support the use of NEON instructions in
kernel mode, some precautions need to be taken:
- the userland context that may be present in the registers (even
  if the NEON/VFP is currently disabled) must be stored under the
  correct task (which may not be 'current' in the UP case),
- to avoid having to keep track of additional vfpstates for the
  kernel side, disallow the use of NEON in interrupt context
  and run with preemption disabled,
- after use, re-enable preemption and re-enable the lazy restore
  machinery by disabling the NEON/VFP unit.

This patch adds the functions kernel_neon_begin() and
kernel_neon_end() which take care of the above. It also adds
the Kconfig symbol KERNEL_MODE_NEON to enable it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Paul Reioux <reioux@gmail.com>
defconfig: enable kernel_mode_NEON