Block: Add the BFQ-v5 I/O scheduler to 3.1

The general structure is borrowed from CFQ, as much code. A
(bfq_)queue is associated to each task doing I/O on a device,
and each time a scheduling decision has to be taken a queue is
selected and it is served until it expires.

    - Slices are given in the service domain: tasks are
      assigned budgets, measured in number of sectors. Once got
      the disk, a task must however consume its assigned budget
      within a configurable maximum time (by default, the
      maximum possible value of the budgets is automatically
      computed to comply with this timeout). This allows the
      desired latency vs "throughput boosting" tradeoff to be
      set.

    - Budgets are scheduled according to a variant of WF2Q+,
      implemented using an augmented rb-tree to take
      eligibility into account while preserving an O(log N)
      overall complexity.

    - A low-latency tunable is provided; if enabled, both
      interactive and soft real-time applications are
      guaranteed very low latency.

    - Latency guarantees are preserved also in presence of NCQ.

    - High throughput with flash-based devices, while still
      preserving latency guarantees.

    - Useful features borrowed from CFQ: cooperating-queues
      merging (with some additional optimizations with respect
      to the original CFQ version), static fallback queue for
      OOM.

    - BFQ supports full hierarchical scheduling, exporting a
      cgroups interface.  Each node has a full scheduler, so
      each group can be assigned its own ioprio and an
      ioprio_class.

    - If the cgroups interface is used, weights can be
      explictly assigned, otherwise ioprio values are mapped
      to weights using the relation
      weight = IOPRIO_BE_NR - ioprio.

    - ioprio classes are served in strict priority order,
      i.e., lower priority queues are not served as long as
      there are higher priority queues.  Among queues in the
      same class the bandwidth is distributed in proportion to
      the weights of each queue. A very thin extra bandwidth
      is however guaranteed to the Idle class, to prevent it
      from starving.

Signed-off-by: Paul Beeler <sparksco@gmail.com>
Enable BFQ Scheduler
bq27541: Add current_now property

The current is returned by the charger as a twos
complement signed integer in milliamps.  Applications
such as CurrentWidget expect this to be microamps.

Signed-off-by: Andrew Dodd <atd7@cornell.edu>
Change-Id: I053b3d1f24ec04391e982fdcb4b3486241c3aa34
lowmemorykiller: Compact memory when killing processes

* Memory compaction is never invoked on Android because we avoid swap
   and don't allocate huge pages. Fix it by invoking compaction from the LMK when
   a process is killed to reduce memory fragmentation.

Change-Id: I2bda790c2093e65fd6f43d52ea5149d6b57cb1e9

Conflicts:

	drivers/staging/android/lowmemorykiller.c
lowmemorykiller: Use asynchronous compaction

Change-Id: I6a65d06fc30b88fcedaaf1abf1855fdd19e3c912
drivers: staging: android: lmk compile fixup

Signed-off-by: Dennis Rassmann <showp1984@gmail.com>
scripts/Kbuild.include: Fix portability problem of "echo -e"

"echo -e" is a GNU extension. When cross-compiling the kernel on a
BSD-like operating system (Mac OS X in my case), this doesn't work.

One could install a GNU version of echo, put that in the $PATH before
the system echo and use "/usr/bin/env echo", but the solution with
printf is simpler.

Since it is no disadvantage on Linux, I hope that gets accepted even if
cross-compiling the Linux kernel on another Unix operating system is
quite a rare use case.

Signed-off-by: Bernhard Walle <bernhard@bwalle.de>
Andreas Bießmann <andreas@biessmann.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>