add extra free kbytes tunable

Add a userspace visible knob to tell the VM to keep an extra amount
of memory free, by increasing the gap between each zone's min and
low watermarks.

This is useful for realtime applications that call system
calls and have a bound on the number of allocations that happen
in any short time period.  In this application, extra_free_kbytes
would be left at an amount equal to or larger than than the
maximum number of allocations that happen in any burst.

It may also be useful to reduce the memory use of virtual
machines (temporarily?), in a way that does not cause memory
fragmentation like ballooning does.

[ccross]
Revived for use on old kernels where no other solution exists.
The tunable will be removed on kernels that do better at avoiding
direct reclaim.

Change-Id: I765a42be8e964bfd3e2886d1ca85a29d60c3bb3e
Signed-off-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Colin Cross <ccross@android.com>
msm: scm: Add scm_call_noalloc and helper macros

Currently, scm_call internally calls kmalloc() to allocate a command
buffer structure. This prevents scm_call from working before kmalloc
structures are initialized or during atomic contexts. Allow clients
to pass in a pre-allocated buffer for scm_call to be used for internal
structures.

Change-Id: Id09500c8c696298228aefdcc2a61953e654677c9
CRs-Fixed: 498392
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
kref: Implement kref_get_unless_zero v3

This function is intended to simplify locking around refcounting for
objects that can be looked up from a lookup structure, and which are
removed from that lookup structure in the object destructor.
Operations on such objects require at least a read lock around
lookup + kref_get, and a write lock around kref_put + remove from lookup
structure. Furthermore, RCU implementations become extremely tricky.
With a lookup followed by a kref_get_unless_zero *with return value check*
locking in the kref_put path can be deferred to the actual removal from
the lookup structure and RCU lookups become trivial.

v2: Formatting fixes.
v3: Invert the return value.

Change-Id: I391623ee7458428eab6d7f361630f8646d6790b0
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Git-commit: 4b20db3de8dab005b07c74161cb041db8c5ff3a7
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[shrenujb@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Shrenuj Bansal <shrenujb@codeaurora.org>
tamsui: include correct kgsl header for new kgsl

Change-Id: Ie1f1e4a1a8beac13089341eb697162c062ea46ce
kgsl: bulk update to kk-2.7

Change-Id: I3b28ae6a4134cd8d1ad45e8f52457959397b0caf