return Jun 28, 2013
sched: task_times() explosion avoidance for tasks with > 2^32 acrued ticks

If stime + utime > 2^32, and lower 32 are 0 when user calls getrusage(),
you've got a dead box.
Signed-off-by: Mike Galbraith <efault@gmx.de>
backported from Linux 3.5+ to Linux 3.0 by faux123
sched,rt: fix isolated CPUs leaving root_task_group indefinitely throttled

Speaking of old "parches" lying about, the below fixes a real problem if
you're using either 'should die' isolcpus or 'should work' cpusets to
isolate cores.

sched,rt: fix isolated CPUs leaving root_task_group indefinitely throttled

Root task group bandwidth replenishment must service all CPUs, regardless of
where the timer was last started, and regardless of the isolation mechanism,
lest 'Quoth the Raven, "Nevermore"' become rt scheduling policy.

Signed-off-by: Mike Galbraith <efault@gmx.de>
backported from Linux 3.5+ to linux 3.0 by faux123
sched: clock wrap bug in 2.6.35-stable kills scheduling

On Mon, 2012-06-25 at 11:45 +0200, Peter Zijlstra wrote:
> On Sun, 2012-06-24 at 19:32 +0200, Thomas Lange wrote:
> > Bug was introduced in 2.6.35.12 and is still present in linux-2.6.35.y HEAD.
>
> Ok, so nobody cares about that.. what does something recent like 3.5-rc4
> do?
>
> If that's fixed, find the patch that fixes it. If not, we'll have a
> look.

If anything, I think something like the below ought to cure things.
sched/fair: Improve the ->group_imb logic

Group imbalance is meant to deal with situations where affinity masks
and sched domains don't align well, such as 3 cpus from one group and
6 from another. In this case the domain based balancer will want to
put an equal amount of tasks on each side even though they don't have
equal cpus.

Currently group_imb is set whenever two cpus of a group have a weight
difference of at least one avg task and the heaviest cpu has at least
two tasks. A group with imbalance set will always be picked as busiest
and a balance pass will be forced.
The problem is that even if there are no affinity masks this stuff can
trigger and cause weird balancing decisions, eg. the observed
behaviour was that of 6 cpus, 5 had 2 and 1 had 3 tasks, due to the
difference of 1 avg load (they all had the same weight) and nr_running
being >1 the group_imbalance logic triggered and did the weird thing
of pulling more load instead of trying to move the 1 excess task to
the other domain of 6 cpus that had 5 cpu with 2 tasks and 1 cpu with
1 task.
Curb the group_imbalance stuff by making the nr_running condition
weaker by also tracking the min_nr_running and using the difference in
nr_running over the set instead of the absolute max nr_running.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-9s7dedozxo8kjsb9kqlrukkf@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
modified for Linux 3.0 from Linux 3.4+ by faux123
sched: fix OOPS when build_sched_domains percpu allocation fails

From: "he, bo" <bo.he@intel.com>

Under extreme memory used up situation, percpu allocation
might fails. We hit it when system go to suspend-to-ram.

EIP: [<c124411a>] build_sched_domains+0x23a/0xad0
SS:ESP 0068:de725d04
CR2: 0000000034811000
---[ end trace d6086359b670b975 ]---
Kernel panic - not syncing: Fatal exception
Pid: 3026, comm: kworker/u:3 Tainted: G      D W
3.0.8-137473-gf42fbef #1
Call Trace:
 [<c18cc4f2>] panic+0x66/0x16c
 [<c12521a1>] ? oops_exit+0x61/0x90
 [<c1205f89>] oops_end+0xb9/0xd0
 [<c1227796>] no_context+0xc6/0x1f0
 [<c1227958>] __bad_area_nosemaphore+0x98/0x140
 [<c1204ebf>] ? dump_trace+0x7f/0xf0
 [<c1227d30>] ? pgtable_bad+0x130/0x130
 [<c1227a17>] bad_area_nosemaphore+0x17/0x20
 [<c1227fa0>] do_page_fault+0x270/0x3c0
 [<c1306afa>] ? pcpu_alloc+0x12ca/0x1300
 [<c1227d30>] ? pgtable_bad+0x130/0x130
 [<c1227d30>] ? pgtable_bad+0x130/0x130
 [<c18d09d3>] error_code+0x5f/0x64
 [<c13000d8>] ? shmem_setattr+0x198/0x230
 [<c1227d30>] ? pgtable_bad+0x130/0x130
 [<c124411a>] ? build_sched_domains+0x23a/0xad0
 [<c18d01a6>] ? _raw_spin_unlock_irqrestore+0x26/0x50
 [<c1244c37>] partition_sched_domains+0x287/0x4b0
 [<c12a77be>] cpuset_update_active_cpus+0x1fe/0x210
 [<c1673017>] ? __cpufreq_remove_dev+0x167/0x360
 [<c18cf03c>] ? down_write+0x1c/0x40
 [<c123712d>] cpuset_cpu_inactive+0x1d/0x30
 [<c127dff2>] notifier_call_chain+0x52/0x90
 [<c127e04e>] __raw_notifier_call_chain+0x1e/0x30
 [<c18b37c9>] _cpu_down+0x89/0x230
 [<c12547f9>] disable_nonboot_cpus+0x79/0x100
 [<c1299fb3>] suspend_devices_and_enter+0x133/0x2e0
 [<c129a27d>] enter_state+0x11d/0x180
 [<c129a307>] pm_suspend+0x27/0x70
 [<c129b8b6>] suspend+0x96/0x1d0
 [<c1271aa3>] process_one_work+0x103/0x400
 [<c129b820>] ? power_suspend_late+0x90/0x90
 [<c12728ac>] worker_thread+0x12c/0x4b0
 [<c123748d>] ? sub_preempt_count+0x3d/0x50
 [<c18d01a6>] ? _raw_spin_unlock_irqrestore+0x26/0x50
 [<c1272780>] ? manage_workers+0x520/0x520
 [<c1276f44>] kthread+0x74/0x80
 [<c1276ed0>] ? __init_kthread_worker+0x30/0x30
 [<c18d113a>] kernel_thread_helper+0x6/0x10
Signed-off-by: he, bo <bo.he@intel.com>
Reviewed-by: Zhang, Yanmin <yanmin.zhang@intel.com>
backported for Linux 3.0 from Linux 3.4+ by faux123
HZ value Change
sched.h: Fix load average calculation for HZ=250 -anarkia1976
Change SIO source
lib: add weak clz/ctz functions
Some architectures need __c[lt]z[sd]i2() for __builtin_c[lt]z[ll] and
It causes build failure. They can be implemented using the fls()/__ffs() and
overridden by linking arch-specific versions may not be implemented yet.

Reference: https://lkml.org/lkml/2013/4/18/603
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Chanho Min <chanho.min@lge.com>
decompressor: Add LZ4decompressor module
This patch adds support for LZ4 decompression in the Linux Kernel.
LZ4 Decompression APIs for kernel are based on LZ4 implementation
by Yann Collet.

LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
LZ4 source repository : http://code.google.com/p/lz4/

Signed-off-by: Kyungsik Lee <kyungsik.lee at lge.com>

v2:
- Clean up code
- Enable unaligned access for ARM v6 and above with
  CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
- Add lz4_decompress() for faster decompression with
  uncompressed output size
v3:
- Fix indent errors
- Prevent double evaluation by using an inline function
lib: Add support forLZ4-compressed kernel
This patch adds support for extracting LZ4-compressed kernel images,
as well as LZ4-compressed ramdisk images in the kernel boot process.

This depends on the patch below
decompressor: Add LZ4 decompressor module

Signed-off-by: Kyungsik Lee <kyungsik.lee at lge.com>

v2:
- Clean up code
- Use lz4_decompress() for LZ4-compressed kernel during boot-process
v3:
- Use an inline function instead of macro to prevent double evaluation
- Add LZ4 description and note for uncompressed chunk size
arm: Add support forLZ4-compressed kernel
This patch integrates the LZ4 decompression code to the arm pre-boot code.
And it depends on two patchs below

lib: Add support for LZ4-compressed kernel
decompressor: Add LZ4 decompressor module

Signed-off-by: Kyungsik Lee <kyungsik.lee at lge.com>

v2:
- Apply CFLAGS, -Os to decompress.o to improve decompress
  performance during boot-up process
lib: Add lz4 compressor module
This patch adds support for LZ4 compression in the Linux Kernel.
LZ4 Compression APIs for kernel are based on LZ4 implementation
by Yann Collet and changed with kernel coding style.

LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
LZ4 source repository : http://code.google.com/p/lz4/
svn revision : r90

Two APIs are added:
lz4_compress() support basic lz4 compression whereas lz4hc_compress() support
high compression or CPU performance get lower but compression ratio get higher.
Also, we require the pre-allocated working memory with the defined size and
destination buffer must be allocated with the size of lz4_compressbound.
crypto: Add lz4 Cryptographic API
This patch adds support for lz4 and lz4hc compression algorithm
using the lib/lz4/* codebase.
Signed-off-by: Chanho Min <chanho.min@lge.com>
msm_ion.c: fix zcache compatibility issues
Signed-off-by: Paul Reioux <reioux@gmail.com>
mm: frontswap: core swap subsystem hooks and headers

This patch, 2of4, contains the changes to the core swap subsystem.
This includes:

(1) makes available core swap data structures (swap_lock, swap_list and
swap_info) that are needed by frontswap.c but we don't need to expose them
to the dozens of files that include swap.h so we create a new swapfile.h
just to extern-ify these and modify their declarations to non-static

(2) adds frontswap-related elements to swap_info_struct.  Frontswap_map
points to vzalloc'ed one-bit-per-swap-page metadata that indicates
whether the swap page is in frontswap or in the device and frontswap_pages
counts how many pages are in frontswap.

(3) adds hooks in the swap subsystem and extends try_to_unuse so that
frontswap_shrink can do a "partial swapoff".

Note that a failed frontswap_map allocation is safe... failure is noted
by lack of "FS" in the subsequent printk.

Conflicts:
	mm/swapfile.c
Add FrontSwap
Update CleanCache
mm: frontswap: doc files
frontswap: s/put_page/store/g s/get_page/load
Sounds so much more natural.

Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>