arm: tegra: hotplug: modify down_delay

Modified the hot-plug governor down_delay to be 500ms instead of 2s

Bug 958978

Change-Id: I55b5a4994f8e4564879cfd206fc683ff6f32d9ac
Signed-off-by: Wen Yi <wyi@nvidia.com>
(cherry picked from commit dd47739)
Reviewed-on: http://git-master/r/111640
Reviewed-by: Sai Gurrappadi <sgurrappadi@nvidia.com>
Tested-by: Sai Gurrappadi <sgurrappadi@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Peter Boonstoppel <pboonstoppel@nvidia.com>
Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
Add Joe's RCU. Original patch from Joe Korty.
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>
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
drivers: mmc: disable CRC.

Enabling software CRCs on the data blocks can be a significant (30%)
performance cost, and for other reasons may not always be desired.
So we allow it it to be disabled.
hrtimer: Prevent hrtimer_enqueue_reprogram race

hrtimer_enqueue_reprogram contains a race which could result in
timer.base switch during unlock/lock sequence.

hrtimer_enqueue_reprogram is releasing the lock protecting the timer
base for calling raise_softirq_irqsoff() due to a lock ordering issue
versus rq->lock.

If during that time another CPU calls __hrtimer_start_range_ns() on
the same hrtimer, the timer base might switch, before the current CPU
can lock base->lock again and therefor the unlock_timer_base() call
will unlock the wrong lock.

[ tglx: Added comment and massaged changelog ]

Change-Id: I327d862c28f24b77a62861764393c4bf660a7318
Signed-off-by: Leonid Shatz <leonid.shatz@ravellosystems.com>
Signed-off-by: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: stable@vger.kernel.org
Link:

http://lkml.kernel.org/r/1359981217-389-1-git-send-email-izik.eidus@ravellosystems.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Git-commit: b22affe
Git-repo:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
hrtimer: Consider preemption when migrating hrtimer cpu_bases

When switching to a new cpu_base in switch_hrtimer_base(), we
briefly enable preemption by unlocking the cpu_base lock in two
places. During this interval it's possible for the running thread
to be swapped to a different CPU.

Consider the following example:

CPU #0                                 CPU #1
----                                   ----
hrtimer_start()                        ...
lock_hrtimer_base()
switch_hrtimer_base()
this_cpu = 0;
target_cpu_base = 0;
raw_spin_unlock(&cpu_base->lock)
<migrate to CPU 1>
...                                    this_cpu == 0
cpu == this_cpu
timer->base = CPU #0
timer->base != LOCAL_CPU

Since the cached this_cpu is no longer accurate, we'll skip the
hrtimer_check_target() check. Once we eventually go to program
the hardware, we'll decide not to do so since it knows the real
CPU that we're running on is not the same as the chosen base. As
a consequence, we may end up missing the hrtimer's deadline.

Fix this by updating the local CPU number each time we retake a
cpu_base lock in switch_hrtimer_base().

Another possibility is to disable preemption across the whole of
switch_hrtimer_base.  This looks suboptimal since preemption
would be disabled while waiting for lock(s).

Change-Id: I3f76d528ab2288ef5f950f4d048e7f3fa6cf1228
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
hrtimer: Prevent enqueue of hrtimer on dead CPU

When switching the hrtimer cpu_base, we briefly allow for
preemption to become enabled by unlocking the cpu_base lock.
During this time, the CPU corresponding to the new cpu_base
that was selected may in fact go offline. In this scenario, the
hrtimer is enqueued to a CPU that's not online, and therefore
it never fires.

As an example, consider this example:

CPU #0                          CPU #1
----                            ----
...                             hrtimer_start()
lock_hrtimer_base()
switch_hrtimer_base()
cpu = hrtimer_get_target() -> 1
spin_unlock(&cpu_base->lock)
<migrate thread to CPU #0>
<offline>
spin_lock(&new_base->lock)
this_cpu = 0
cpu != this_cpu
enqueue_hrtimer(cpu_base #1)

To prevent this scenario, verify that the CPU corresponding to
the new cpu_base is indeed online before selecting it in
hrtimer_switch_base(). If it's not online, fallback to using the
base of the current CPU.

Change-Id: I6359cb299ba7e08abf25d3360fcdd925b4c03b69
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
switch do_fsync() to fget_light()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Makefile: Added ARM optimizations
add arm optimizations
Increased default readahead value to 1024kB.
Added FSync Control version 1 by Ezekeel

fsync default : false
cpufreq: interactive: Add Uevent Signal on Gov Start

Sends kobject_uevent signal back to userspace to signal that
the cpufreq governor has been set to interactive

Bug 1039141

Change-Id: I699e9d5834a1874b36c675764c080112ccba0f9f
Signed-off-by: Matt Wagner <mwagner@nvidia.com>
Reviewed-on: http://git-master/r/131224
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Dan Willemsen <dwillemsen@nvidia.com>
adapted for Grouper from NV reference

Signed-off-by: faux123 <reioux@gmail.com>
set GPU @ 520 MHz

credit to showp1984