msm: Allow lowmem to be non contiguous and mixed.

Any image that is expected to have a lifetime of
the entire system can give the virtual address
space back for use in vmalloc.

Change-Id: I81ce848cd37e8573d706fa5d1aa52147b3c8da12
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
msm: Increase the kernel virtual area to include lowmem

Even though lowmem is accounted for in vmalloc space, allocation
comes only from the region bounded by VMALLOC_START and VMALLOC_END.
The kernel virtual area can now allocate from any unmapped region
starting from PAGE_OFFSET.

Change-Id: I291b9eb443d3f7445fd979bd7b09e9241ff22ba3
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
mm: Remove __init annotations from free_bootmem_late

free_bootmem_late is currently set up to only be used in init
functions. Some clients need to use this function past initcalls.
The functions themselves have no restrictions on being used later
minus the __init annotations so remove the annotation.

Change-Id: I7c7e15cf2780a8843ebb4610da5b633c9abb0b3d
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: panic on the first bad page table entry access

Sometimes having a number of bad page table entries precipitates in
a crash much later. Because of this, we do not have any context for
the point at which the first bad pte entry was encountered. Hence,
panic on first such instance to help gather context for debug.

Change-Id: Idddf2b977214eb1463d08e16630e98264b9af487
Signed-off-by: Pushkar Joshi <pushkarj@codeaurora.org>
debug-pagealloc: Panic on pagealloc corruption

Currently, we just print the pagealloc corruption warnings and
proceed. Sometimes, we are getting multiple errors printed down
the line. It will be good to get the device state as early as
possible when we get the first pagealloc error.

Change-Id: I79155ac8a039b30a3a98d5dd1384d3923082712f
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
mm: Update is_vmalloc_addr to account for vmalloc savings

is_vmalloc_addr current assumes that all vmalloc addresses
exist between VMALLOC_START and VMALLOC_END. This may not be
the case when interleaving vmalloc and lowmem. Update the
is_vmalloc_addr to properly check for this.

Change-Id: I5def3d6ae1a4de59ea36f095b8c73649a37b1f36
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
mm: methods for teaching filesystems about PG_swapcache pages

In order to teach filesystems to handle swap cache pages, three new page
functions are introduced:

  pgoff_t page_file_index(struct page *);
  loff_t page_file_offset(struct page *);
  struct address_space *page_file_mapping(struct page *);

page_file_index() - gives the offset of this page in the file in
PAGE_CACHE_SIZE blocks.  Like page->index is for mapped pages, this
function also gives the correct index for PG_swapcache pages.

page_file_offset() - uses page_file_index(), so that it will give the
expected result, even for PG_swapcache pages.

page_file_mapping() - gives the mapping backing the actual page; that is
for swap cache pages it will give swap_file->f_mapping.

Change-Id: I13d18bb25be606760eac26cc842eb7c9fc9e4766
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Paris <eparis@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Xiaotian Feng <dfeng@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit: f981c5950fa85916ba49bea5d9a7a5078f47e569
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
[ohaugan@codeaurora.org: Resolved merge issues]
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
mm: swap: Rate limit swap write errors

If an error occurs in the swap subsystem when writing pages
out to a swap device the system might get overflowed with
logging errors because the mm subsystem will continously try
to swap out pages even in the event of error on the swap
device.

Reduce the amount of logging to prevent the kernel log
from being filled with these error messages.

Change-Id: Iddaf6c32ae87132817482cc4cb68b909a1c527e6
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Kconfig: Enable config to allow vmalloc savings

Select the config to reclaim the vmalloc space in lowmem
and disable the map around the hole config, where selected,
as both the configs cannot be enabled together

CRs-Fixed: 568470
Change-Id: I9dd3e0123e4fe3e33554cdbdf5a82e344c230f47
Signed-off-by: Neeti Desai <neetid@codeaurora.org>

Conflicts:
	arch/arm/mach-msm/Kconfig
Kconfig: Add config option to support vmalloc savings

The virtual space belonging to any subsystem which is
expected to have a lifetime of the entire system can be
reclaimed. Adding config option to enable or disable
this feature.

Change-Id: I56faef4b71c948185fdfe336054a5951dfa8d011
Signed-off-by: Neeti Desai <neetid@codeaurora.org>

Conflicts:
	arch/arm/Kconfig
Kconfig: Add menu choice option to reclaim virtual memory

Add menu choice options for selecting the method of reclaiming
virtual memory, either by mapping around the largest hole or
reclaiming virtual memory belonging to any subsystem expected to
have a lifetime of the entire system. By default virtual memory
is not reclaimed.

Change-Id: I1b8a1492062bb9532700122878618989e5148647
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
msm: Update the kernel log messages

After reclaiming vmalloc and adjusting lowmem, the two regions
are no longer contiguous. Update the messages printed during
bootup to list all regions corresponding to low memory and vmalloc
respectively

Change-Id: I2aeb25026c068e27860c3df1496fc6f5c420b818
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
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>
Git-commit: 92189d47f66c67e5fd92eafaa287e153197a454f
Git-repo: https://android.googlesource.com/kernel/common/
[bhargavuln@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Bhargav Upperla <bhargavuln@codeaurora.org>
msm: Adjust the low memory boundary

The unused virtual address space in low memory is given to
vmalloc for use. This reduces the low memory space and
increases vmalloc space. Adjust the vmalloc_min in order
to increase the low memory.

Change-Id: I0dbef5b6e5ec3d19f5f93f06ed03a4cf1215dc4d
Signed-off-by: Neeti Desai <neetid@codeaurora.org>
mm: make is_vmalloc_addr lockless

is_vmalloc_addr currently takes the vmap_area_lock and walks
the list of vmalloc areas to determine if an address is actually
a vmalloc address. Unfortunately, the current locking structure
with vmap_area_lock does not disable irqs which means that it may
be possible to recusively take the vmap_area_lock if an irq occurs
while walking the tree list. Considering the list of possible
vmalloc vs. not vmalloc ranges is not going to change after bootup,
skip the tree walking and just keep a bitmap of which virtual
addresses are set aside for vmalloc and which are not.

Change-Id: I0c159e09dc17b5c6641d08dcf630e6116b991cd5
CRs-Fixed: 591797
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
defconfig: Update

Signed-off-by: Kostas K <mpokwsths@gmail.com>
Revert "mm: make is_vmalloc_addr lockless"

This reverts commit 7fbec2ba211503b3ca7cfdbac98ad90ab6f818e7.
mm: make is_vmalloc_addr work properly.

There was a typo in the config guard for CONFIG_ENABLE_VMALLOC_SAVING
which meant that the code was never actually being compiled. As a
result, it was never noticed that the code had major flaws. Fix
the code to actually work as intended.

Change-Id: Ief3c00d16cf54e3b945ffb1bfde6b1fea2fa142e
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>

Conflicts:
	mm/vmalloc.c
mm: make is_vmalloc_addr lockless

is_vmalloc_addr currently takes the vmap_area_lock and walks
the list of vmalloc areas to determine if an address is actually
a vmalloc address. Unfortunately, the current locking structure
with vmap_area_lock does not disable irqs which means that it may
be possible to recusively take the vmap_area_lock if an irq occurs
while walking the tree list. Considering the list of possible
vmalloc vs. not vmalloc ranges is not going to change after bootup,
skip the tree walking and just keep a bitmap of which virtual
addresses are set aside for vmalloc and which are not.

Change-Id: I0c159e09dc17b5c6641d08dcf630e6116b991cd5
CRs-Fixed: 591797
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>

Conflicts:
	arch/arm/mm/mmu.c
ARM: smp: Save CPU registers before IPI_CPU_STOP processing

When a kernel panic occurs on one CPU, other CPUs are instructed to stop
execution via the IPI_CPU_STOP message. These other CPUs dump their stack,
which may not be good enough to reconstruct their context to perform
post-mortem analysis. Dump each CPU's context
(before it started procesing the IPI) into a globally accessible structure
to allow for easier post-mortem debugging.

Change-Id: I68ac75f73d7ddaebaff9122b23e341bcb00e8fb9
Signed-off-by: Tingting Yang <tingting@codeaurora.org>