We have removed the remap allocator for x86-32, and x86-64 never had
it (and doesn't need it).  Remove residual reference to it.
Reported-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/CAE9FiQVn6_QZi3fNQ-JHYiR-7jeDJ5hT0SyT_%2BzVvfOj=PzF3w@mail.gmail.com

This code was an optimization for 32-bit NUMA systems.

It has probably been the cause of a number of subtle bugs over
the years, although the conditions to excite them would have
been hard to trigger.  Essentially, we remap part of the kernel
linear mapping area, and then sometimes part of that area gets
freed back in to the bootmem allocator.  If those pages get
used by kernel data structures (say mem_map[] or a dentry),
there's no big deal.  But, if anyone ever tried to use the
linear mapping for these pages _and_ cared about their physical
address, bad things happen.

For instance, say you passed __GFP_ZERO to the page allocator
and then happened to get handed one of these pages, it zero the
remapped page, but it would make a pte to the _old_ page.
There are probably a hundred other ways that it could screw
with things.

We don't need to hang on to performance optimizations for
these old boxes any more.  All my 32-bit NUMA systems are long
dead and buried, and I probably had access to more than most
people.

This code is causing real things to break today:

	https://lkml.org/lkml/2013/1/9/376

I looked in to actually fixing this, but it requires surgery
to way too much brittle code, as well as stuff like
per_cpu_ptr_to_phys().

[ hpa: Cc: this for -stable, since it is a memory corruption issue.
  However, an alternative is to simply mark NUMA as depends BROKEN
  rather than EXPERIMENTAL in the X86_32 subclause... ]

Link: http://lkml.kernel.org/r/20130131005616.1C79F411@kernel.stglabs.ibm.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>

... and fix the following warning:

  arch/x86/mm/numa.c: In function ‘setup_node_data’:
  arch/x86/mm/numa.c:222:3: warning: passing argument 1 of ‘__phys_addr_nodebug’ makes integer from pointer without a cast
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NDave Hansen <dave@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1359245901-8512-1-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

The KVM code has some repeated bugs in it around use of __pa() on
per-cpu data.  Those data are not in an area on which using
__pa() is valid.  However, they are also called early enough in
boot that __vmalloc_start_set is not set, and thus the
CONFIG_DEBUG_VIRTUAL debugging does not catch them.

This adds a check to also verify __pa() calls against max_low_pfn,
which we can use earler in boot than is_vmalloc_addr().  However,
if we are super-early in boot, max_low_pfn=0 and this will trip
on every call, so also make sure that max_low_pfn is set before
we try to use it.

With this patch applied, CONFIG_DEBUG_VIRTUAL will actually
catch the bug I was chasing (and fix later in this series).

I'd love to find a generic way so that any __pa() call on percpu
areas could do a BUG_ON(), but there don't appear to be any nice
and easy ways to check if an address is a percpu one.  Anybody
have ideas on a way to do this?
Signed-off-by: NDave Hansen <dave@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20130122212430.F46F8159@kernel.stglabs.ibm.comSigned-off-by: NH. Peter Anvin <hpa@linux.intel.com>

Print physical address info in a style consistent with the %pR style used
elsewhere in the kernel.  For example:

    -found SMP MP-table at [ffff8800000fce90] fce90
    +found SMP MP-table at [mem 0x000fce90-0x000fce9f] mapped at [ffff8800000fce90]
    -initial memory mapped : 0 - 20000000
    +initial memory mapped: [mem 0x00000000-0x1fffffff]
    -Base memory trampoline at [ffff88000009c000] 9c000 size 8192
    +Base memory trampoline [mem 0x0009c000-0x0009dfff] mapped at [ffff88000009c000]
    -SRAT: Node 0 PXM 0 0-80000000
    +SRAT: Node 0 PXM 0 [mem 0x00000000-0x7fffffff]
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

node_to_cpumask() has been replaced by cpumask_of_node(), and wholly
removed since commit 29c337a0 ("cpumask: remove obsolete node_to_cpumask
now everyone uses cpumask_of_node").

So update the comments for setup_node_to_cpumask_map().
Signed-off-by: NWanlong Gao <gaowanlong@cn.fujitsu.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds constraint checks to the numa_set_distance()
function.

When the check triggers (this should not happen normally) it
emits a warning and avoids a store to a negative index in
numa_distance[] array - i.e. avoids memory corruption.

Negative ids can be passed when the pxm-to-nids mapping is not
properly filled while parsing the SRAT.
Signed-off-by: NPetr Holasek <pholasek@redhat.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Anton Arapov <anton@redhat.com>
Link: http://lkml.kernel.org/r/20111208121640.GA2229@dhcp-27-244.brq.redhat.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

Other than sanity check and debug message, the x86 specific version of
memblock reserve/free functions are simple wrappers around the generic
versions - memblock_reserve/free().

This patch adds debug messages with caller identification to the
generic versions and replaces x86 specific ones and kills them.
arch/x86/include/asm/memblock.h and arch/x86/mm/memblock.c are empty
after this change and removed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-14-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

memblock_x86_hole_size() calculates the total size of holes in a given
range according to memblock and is used by numa emulation code and
numa_meminfo_cover_memory().

Since conversion to MEMBLOCK_NODE_MAP, absent_pages_in_range() also
uses memblock and gives the same result.  This patch replaces
memblock_x86_hole_size() uses with absent_pages_in_range().  After the
conversion the x86 function doesn't have any user left and is killed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310462166-31469-12-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

From 5732e1247898d67cbf837585150fe9f68974671d Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 14 Jul 2011 11:22:16 +0200

Convert x86 to HAVE_MEMBLOCK_NODE_MAP.  The only difference in memory
handling is that allocations can't no longer cross node boundaries
whether they're node affine or not, which shouldn't matter at all.

This conversion will enable further simplification of boot memory
handling.

-v2: Fix build failure on !NUMA configurations discovered by hpa.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110714094423.GG3455@htj.dyndns.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

With the previous changes, generic NUMA aware memblock API has feature
parity with memblock_x86_find_in_range_node().  There currently are
two users - x86 setup_node_data() and __alloc_memory_core_early() in
nobootmem.c.

This patch converts the former to use memblock_alloc_nid() and the
latter memblock_find_range_in_node(), and kills
memblock_x86_find_in_range_node() and related functions including
find_memory_early_core_early() in page_alloc.c.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310460395-30913-9-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

25818f0f (memblock: Make MEMBLOCK_ERROR be 0) thankfully made
MEMBLOCK_ERROR 0 and there already are codes which expect error return
to be 0.  There's no point in keeping MEMBLOCK_ERROR around.  End its
misery.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1310457490-3356-6-git-send-email-tj@kernel.org
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

SPARSEMEM w/o VMEMMAP and DISCONTIGMEM, both used only on 32bit, use
sections array to map pfn to nid which is limited in granularity.  If
NUMA nodes are laid out such that the mapping cannot be accurate, boot
will fail triggering BUG_ON() in mminit_verify_page_links().

On 32bit, it's 512MiB w/ PAE and SPARSEMEM.  This seems to have been
granular enough until commit 2706a0bf (x86, NUMA: Enable
CONFIG_AMD_NUMA on 32bit too).  Apparently, there is a machine which
aligns NUMA nodes to 128MiB and has only AMD NUMA but not SRAT.  This
led to the following BUG_ON().

 On node 0 totalpages: 2096615
   DMA zone: 32 pages used for memmap
   DMA zone: 0 pages reserved
   DMA zone: 3927 pages, LIFO batch:0
   Normal zone: 1740 pages used for memmap
   Normal zone: 220978 pages, LIFO batch:31
   HighMem zone: 16405 pages used for memmap
   HighMem zone: 1853533 pages, LIFO batch:31
 BUG: Int 6: CR2   (null)
      EDI   (null)  ESI 00000002  EBP 00000002  ESP c1543ecc
      EBX f2400000  EDX 00000006  ECX   (null)  EAX 00000001
      err   (null)  EIP c16209aa   CS 00000060  flg 00010002
 Stack: f2400000 00220000 f7200800 c1620613 00220000 01000000 04400000 00238000
          (null) f7200000 00000002 f7200b58 f7200800 c1620929 000375fe   (null)
        f7200b80 c16395f0 00200a02 f7200a80   (null) 000375fe 00000002   (null)
 Pid: 0, comm: swapper Not tainted 2.6.39-rc5-00181-g2706a0bf #17
 Call Trace:
  [<c136b1e5>] ? early_fault+0x2e/0x2e
  [<c16209aa>] ? mminit_verify_page_links+0x12/0x42
  [<c1620613>] ? memmap_init_zone+0xaf/0x10c
  [<c1620929>] ? free_area_init_node+0x2b9/0x2e3
  [<c1607e99>] ? free_area_init_nodes+0x3f2/0x451
  [<c1601d80>] ? paging_init+0x112/0x118
  [<c15f578d>] ? setup_arch+0x791/0x82f
  [<c15f43d9>] ? start_kernel+0x6a/0x257

This patch implements node_map_pfn_alignment() which determines
maximum internode alignment and update numa_register_memblks() to
reject NUMA configuration if alignment exceeds the pfn -> nid mapping
granularity of the memory model as determined by PAGES_PER_SECTION.

This makes the problematic machine boot w/ flatmem by rejecting the
NUMA config and provides protection against crazy NUMA configurations.
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110712074534.GB2872@htj.dyndns.org
LKML-Reference: <20110628174613.GP478@escobedo.osrc.amd.com>
Reported-and-Tested-by: NHans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Conny Seidel <conny.seidel@amd.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>

During testing 32bit numa unifying code from tj, found one system with
more than 64g fails to use numa.  It turns out we do not trim numa
meminfo correctly against max_pfn in case start address of a node is
higher than 64GiB.  Bug fix made it to tip tree.

This patch moves the checking and trimming to a separate loop.  So we
don't need to compare low/high in following merge loops.  It makes the
code more readable.

Also it makes the node merge printouts less strange.  On a 512GiB numa
system with 32bit,

before:
> NUMA: Node 0 [0,a0000) + [100000,80000000) -> [0,80000000)
> NUMA: Node 0 [0,80000000) + [100000000,1080000000) -> [0,1000000000)

after:
> NUMA: Node 0 [0,a0000) + [100000,80000000) -> [0,80000000)
> NUMA: Node 0 [0,80000000) + [100000000,1000000000) -> [0,1000000000)
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
[Updated patch description and comment slightly.]
Signed-off-by: NTejun Heo <tj@kernel.org>

After using memblock to replace bootmem, that function only sets up
node_data now.

Change the name to reflect what it actually does.

tj: Minor adjustment to the patch description.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NTejun Heo <tj@kernel.org>

numa_init_array() no longer has users outside of numa.c.  Make it
static.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

With both _numa_init() methods converted and the rest of init code
adjusted, numa_32.c now can switch from the 32bit only init code to
the common one in numa.c.

* Shim get_memcfg_*()'s are dropped and initmem_init() calls
  x86_numa_init(), which is updated to handle NUMAQ.

* All boilerplate operations including node range limiting, pgdat
  alloc/init are handled by numa_init().  32bit only implementation is
  removed.

* 32bit numa_add_memblk(), numa_set_distance() and
  memory_add_physaddr_to_nid() removed and common versions in
  numa_32.c enabled for 32bit.

This change causes the following behavior changes.

* NODE_DATA()->node_start_pfn/node_spanned_pages properly initialized
  for 32bit too.

* Much more sanity checks and configuration cleanups.

* Proper handling of node distances.

* The same NUMA init messages as 64bit.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

setup_node_bootmem() is taken from 64bit and doesn't use remap
allocator.  It's about to be shared with 32bit so add support for it.
If NODE_DATA is remapped, it's noted in the debug message and node
locality check is skipped as the __pa() of the remapped address
doesn't reflect the actual physical address.

On 64bit, remap allocator becomes noop and doesn't affect the
behavior.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Code moved from numa_64.c has assumption that long is 64bit in several
places.  This patch removes the assumption by using {s|u}64_t
explicity, using PFN_PHYS() for page number -> addr conversions and
adjusting printf formats.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Generic NUMA init code was moved to numa.c from numa_64.c but is still
guaraded by CONFIG_X86_64.  This patch removes the compile guard and
enables compiling on 32bit.

* numa_add_memblk() and numa_set_distance() clash with the shim
  implementation in numa_32.c and are left out.

* memory_add_physaddr_to_nid() clashes with 32bit implementation and
  is left out.

* MAX_DMA_PFN definition in dma.h moved out of !CONFIG_X86_32.

* node_data definition in numa_32.c removed in favor of the one in
  numa.c.

There are places where ulong is assumed to be 64bit.  The next patch
will fix them up.  Note that although the code is compiled it isn't
used yet and this patch doesn't cause any functional change.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Move the generic 64bit NUMA init machinery from numa_64.c to numa.c.

* node_data[], numa_mem_info and numa_distance
* numa_add_memblk[_to](), numa_remove_memblk[_from]()
* numa_set_distance() and friends
* numa_init() and all the numa_meminfo handling helpers called from it
* dummy_numa_init()
* memory_add_physaddr_to_nid()

A new function x86_numa_init() is added and the content of
numa_64.c::initmem_init() is moved into it.  initmem_init() now simply
calls x86_numa_init().

Constants and numa_off declaration are moved from numa_{32|64}.h to
numa.h.

This is code reorganization and doesn't involve any functional change.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Move numa_nodes_parsed from numa_64.[hc] to numa.[hc] to prepare for
NUMA init path unification.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

Currently, the only meaningful user of apic->x86_32_numa_cpu_node() is
NUMAQ which returns valid mapping only after CPU is initialized during
SMP bringup; thus, the previous patch to set apicid -> node in
setup_local_APIC() makes __apicid_to_node[] always contain the correct
mapping whether custom apic->x86_32_numa_cpu_node() is used or not.

So, there is no reason to keep separate 32bit implementation.  We can
always consult __apicid_to_node[].  Move 64bit implementation from
numa_64.c to numa.c and remove 32bit implementation from numa_32.c.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>

The cpu<->node mappings under CONFIG_DEBUG_PER_CPU_MAPS=y
when NUMA emulation is enabled is currently broken because it does
not iterate through every emulated node and bind cpus that have
affinity to it.

NUMA emulation should bind each cpu to every local node to
accurately represent the true NUMA topology of the underlying
machine.

debug_cpumask_set_cpu() needs to be fixed at the same time so
that the debugging information that it emits shows the new
cpumask of the node being assigned when the cpu is being added
or removed.

It can now take responsibility of setting or clearing the cpu
itself to remove the need for duplicate code.

Also change its last parameter, "enable", to have the correct bool
type since it can only be true or false.

 -v2: Fix the return statements, by Kosaki Motohiro
Acked-and-Tested-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1104201918470.12634@chino.kir.corp.google.comSigned-off-by: NIngo Molnar <mingo@elte.hu>

CONFIG_DEBUG_PER_CPU_MAPS may return NUMA_NO_NODE when an
early_cpu_to_node() mapping hasn't been initialized.  In such a
case, it emits a warning and continues without an issue but
callers may try to use the return value to index into an array.

We can catch those errors and fail silently since a warning has
already been emitted.  No current user of numa_add_cpu()
requires this error checking to avoid a crash, but it's better
to be proactive in case a future user happens to have a bug and
a user tries to diagnose it with CONFIG_DEBUG_PER_CPU_MAPS.
Reported-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Tejun Heo <tj@kernel.org>
LKML-Reference: <alpine.DEB.2.00.1102071407250.7812@chino.kir.corp.google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Now that everything else is unified, NUMA initialization can be
unified too.

* numa_init_array() and init_cpu_to_node() are moved from
  numa_64 to numa.

* numa_32::initmem_init() is updated to call numa_init_array()
  and setup_arch() to call init_cpu_to_node() on 32bit too.

* x86_cpu_to_node_map is now initialized to NUMA_NO_NODE on
  32bit too. This is safe now as numa_init_array() will initialize
  it early during boot.

This makes NUMA mapping fully initialized before
setup_per_cpu_areas() on 32bit too and thus makes the first
percpu chunk which contains all the static variables and some of
dynamic area allocated with NUMA affinity correctly considered.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-17-git-send-email-tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: NPekka Enberg <penberg@kernel.org>

x86_32 has been managing node_to_cpumask_map explicitly from
map_cpu_to_node() and friends in a rather ugly way.  With
previous changes, it's now possible to share the code with
64bit.

* When CONFIG_NUMA_EMU is disabled, numa_add/remove_cpu() are
  implemented in numa.c and shared by 32 and 64bit.  CONFIG_NUMA_EMU
  versions still live in numa_64.c.

  NUMA_EMU's dependency on 64bit is planned to be removed and the
  above should go away together.

* identify_cpu() now calls numa_add_cpu() for 32bit too.  This
  makes the explicit mask management from map_cpu_to_node() unnecessary.

* The whole x86_32 specific map_cpu_to_node() chunk is no longer
  necessary.  Dropped.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NPekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-16-git-send-email-tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>

Unlike 64bit, 32bit has been using its own cpu_to_node_map[] for
CPU -> NUMA node mapping.  Replace it with early_percpu variable
x86_cpu_to_node_map and share the mapping code with 64bit.

* USE_PERCPU_NUMA_NODE_ID is now enabled for 32bit too.

* x86_cpu_to_node_map and numa_set/clear_node() are moved from
  numa_64 to numa.  For now, on 32bit, x86_cpu_to_node_map is initialized
  with 0 instead of NUMA_NO_NODE.  This is to avoid introducing unexpected
  behavior change and will be updated once init path is unified.

* srat_detect_node() is now enabled for x86_32 too.  It calls
  numa_set_node() and initializes the mapping making explicit
  cpu_to_node_map[] updates from map/unmap_cpu_to_node() unnecessary.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-15-git-send-email-tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>

The mapping between cpu/apicid and node is done via
apicid_to_node[] on 64bit and apicid_2_node[] +
apic->x86_32_numa_cpu_node() on 32bit. This difference makes it
difficult to further unify 32 and 64bit NUMA handling.

This patch unifies it by replacing both apicid_to_node[] and
apicid_2_node[] with __apicid_to_node[] array, which is accessed
by two accessors - set_apicid_to_node() and numa_cpu_node().  On
64bit, numa_cpu_node() always consults __apicid_to_node[]
directly while 32bit goes through apic->numa_cpu_node() method
to allow apic implementations to override it.

srat_detect_node() for amd cpus contains workaround for broken
NUMA configuration which assumes relationship between APIC ID,
HT node ID and NUMA topology.  Leave it to access
__apicid_to_node[] directly as mapping through CPU might result
in undesirable behavior change.  The comment is reformatted and
updated to note the ugliness.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reviewed-by: NPekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-14-git-send-email-tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>

In order to be able to suppress the use of SRAT tables that
32-bit Linux can't deal with (in one case known to lead to a
non-bootable system, unless disabling ACPI altogether), move the
"numa=" option handling to common code.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Reviewed-by: NThomas Renninger <trenn@suse.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Renninger <trenn@suse.de>
LKML-Reference: <4D36B581020000780002D0FF@vpn.id2.novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

DBG() macro for CONFIG_DEBUG_PER_CPU_MAPS is unused.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <1274706291-13554-1-git-send-email-akinobu.mita@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This reverts commit 0ac0c0d0, which
caused cross-architecture build problems for all the wrong reasons.
IA64 already added its own version of __node_random(), but the fact is,
there is nothing architectural about the function, and the original
commit was just badly done. Revert it, since no fix is forthcoming.
Requested-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some workloads that create a large number of small files tend to assign
too many pages to node 0 (multi-node systems).  Part of the reason is that
the rotor (in cpuset_mem_spread_node()) used to assign nodes starts at
node 0 for newly created tasks.

This patch changes the rotor to be initialized to a random node number of
the cpuset.

[akpm@linux-foundation.org: fix layout]
[Lee.Schermerhorn@hp.com: Define stub numa_random() for !NUMA configuration]
Signed-off-by: NJack Steiner <steiner@sgi.com>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Paul Menage <menage@google.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Impact: fix (CONFIG_MAXSMP=y only) boot crash

c032ef60 "cpumask: convert
node_to_cpumask_map[] to cpumask_var_t" didn't get this one
conversion.  There was a compile warning, but I missed it.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903132342.42813.rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

We are removing cpumask_t in favour of struct cpumask: mainly as a
marker of what code is now CONFIG_CPUMASK_OFFSTACK-safe.

The only non-trivial change here is vector_allocation_domain():
explicitly clear the mask and set the first word, rather than using
assignment.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y

Straightforward conversion: done for 32 and 64 bit kernels.
node_to_cpumask_map is now a cpumask_var_t array.

64-bit used to be a dynamic cpumask_t array, and 32-bit used to be a
static cpumask_t array.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

We take the 64-bit code and use it on 32-bit as well.  The new file
is called mm/numa.c.

In a minor cleanup, we use cpu_none_mask instead of declaring a local
cpu_mask_none.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>