ashmem: Fix deadlock when System is low on memory
My own defconfig
init/main.c: execute lockdep_init as early as possible
From: Ming Lei <tom.leiming@gmail.com>

This patch removes the lockdep warning[1] on ARM platform.
The warning is caused by printk inside smp_setup_processor_id.

It is safe to do this because lockdep_init doesn't depend on
smp_setup_processor_id, so make printk can be called as early
as possible without lockdep complainment.

[1], lockdep warning
[    0.000000] WARNING: lockdep init error! Arch code didn't call
lockdep_init() early enough?
[    0.000000] Call stack leading to lockdep invocation was:
[    0.000000]  [<c00164bc>] save_stack_trace_tsk+0x0/0x90
[    0.000000]  [<ffffffff>] 0xffffffff
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
lowmemorykiller: Don't try to kill the same pid over and over

  Under certain circumstances, a process can take awhile to
handle a sig-kill (especially if it's in a scheduler group with
a very low share ratio). When this occurs, lowmemkiller returns
to vmscan indicating the process memory has been freed - even
though the process is still waiting to die. Since the memory
hasn't actually freed, lowmemkiller is called again shortly after,
and picks the same process to die; regardless of the fact that
it has already been 'scheduled' to die and the memory has already
been reported to vmscan as having been freed.

  Solution is to check fatal_signal_pending() on the selected
task, and if it's already pending destruction return; indicating
to vmscan that no resources were freed on this pass.

Signed-off-by: San Mehat <san@google.com>
Added optimized ARM RWSEM algorithm.
sched: don't call task_group() many times in set_task_rq()

It improves perfomance, especially if autogroup enabled.

The size of set_task_rq() was 0x180 and now it is 0xa0.

Signed-off-by: Andrew Vagin <avagin@openvz.org>
sched/rt: code cleanup, remove a redundant function call

The second time call to sched_rt_period is redundant, because the value of the
rt_runtime was already read and it was protected by the rurt_runtime_lock.

Signed-off-by: Shan Hai <haishan.bai@gmail.com>
nohz: Remove ts->inidle checks before restarting the tick

ts->inidle is set by tick_nohz_stop_sched_tick(1) and unset
by tick_nohz_restart_sched_tick(). These two calls are assumed
to be always paired. This means that by the time we call
tick_nohz_restart_sched_tick(), ts->inidle is supposed to
be always set to 1.

Remove the checks for ts->inidle in tick_nohz_restart_sched_tick().
This simplifies a bit the code and improves its debuggability
(ie: ensure the call is paired with a tick_nohz_stop_sched_tick() call).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
sched: enable ARCH_POWER

Enable the scheduler feature that allows use of arch_scale_smt_power. Stub out
the broken x86 implementation.

Signed-off-by: Joel Schopp <jschopp@xxxxxxxxxxxxxx>
RCU: Joe's RCU

Forward port jRCU to linux-3.0.

Thanks goes to Francisco Franco for his help
in testing out this version on the Android
Galaxy Nexus phone.

Signed-off-by: Joe Korty <joe.korty@ccur.com>
Signed-off-by: Ezekeel <notezekeel@googlemail.com>
Proportional Rate Reduction for TCP - by Google
neither TCP resets nor ICMP destination-unreachable packets will be sent in response to packets sent to ports for which no associated listening process exists
lib: add generic strnlen_user() function

This adds a new generic optimized strnlen_user() function that uses the
<asm/word-at-a-time.h> infrastructure to portably do efficient string
handling.

In many ways, strnlen is much simpler than strncpy, and in particular we
can always pre-align the words we load from memory.  That means that all
the worries about alignment etc are a non-issue, so this one can easily
be used on any architecture.  You obviously do have to do the
appropriate word-at-a-time.h macros.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NOATIME and NODIRATIME by default