NUMA emulation needs to update node distance information.  It did it
by remapping apicid to PXM mapping, even when amdtopology is being
used.  There is no reason to go through such convolution.  The generic
code has all the information necessary to transform the distance table
to the emulated nid space.

Implement generic distance table transformation in numa_emulation()
and drop private implementations in srat_64 and amdtopology_64.  This
makes find_node_by_addr() and fake_physnodes() and related functions
unnecessary, drop them.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

NUMA emulation changes node mappings and thus apicid -> node mapping
needs to be updated accordingly.  srat_64 and amdtopology_64 did this
separately; however, all the necessary information is the mapping from
emulated nodes to physical nodes which is available in
emu_nid_to_phys[].

Implement common __apicid_to_node[] transformation in numa_emulation()
and drop duplicate implementations.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

NUMA emulation built physnodes[] array which could only represent
configurations from the physical meminfo and emulated nodes using the
information.  There's no reason to take this extra level of
indirection.  Update emulation functions so that they operate directly
on numa_meminfo.  This simplifies the code and makes emulation layout
behave better with interleaved physical nodes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Both emulation layout functions - split_nodes[_size]_interleave() -
didn't wrap emulated nid while laying out the fake nodes and tried to
avoid interating over the specified number of nodes, which is fragile.

Now that the emulation code generates numa_meminfo, the node memblks
don't need to be consecutive and emulated node IDs can simply wrap.
This makes the code more robust and is necessary for updates to better
handle the cases where the physical nodes are interleaved.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

NUMA emulation code built nodes[] array and had its own registration
path to set up the emulated nodes.  Update it such that it generates
emulated numa_meminfo and returns control to initmem_init() and shares
the same registration path with non-emulated cases.

Because {acpi|amd}_fake_nodes() expect nodes[] parameter,
fake_physnodes() now generates nodes[] from numa_meminfo.  This will
go away with further updates.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

NUMA emulation copied physical NUMA configuration into physnodes[] and
used it to reverse-map emulated nodes to physical nodes, which is
unnecessarily convoluted.  Build emu_nid_to_phys[] array to map
emulated nids directly to the matching physical nids and use it in
numa_add_cpu().

physnodes[] will be removed with further patches.

- v2: Build failure when CONFIG_DEBUG_PER_CPU_MAPS due to missing
  local variable definition fixed.  Reported by Ingo.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

* Separate out numa_add_memblk_to() from numa_add_memblk() so that
  different numa_meminfo can be used.

* Rename cmdline to emu_cmdline.

* Drop @start/last_pfn from numa_emulation() and use max_pfn directly.

This patch doesn't introduce any behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Node distance either used direct node comparison, ACPI PXM comparison
or ACPI SLIT table lookup.  This patch implements generic node
distance handling.  NUMA init methods can call numa_set_distance() to
set distance between nodes and the common __node_distance()
implementation will report the set distance.

Due to the way NUMA emulation is implemented, the generic node
distance handling is used only when emulation is not used.  Later
patches will update NUMA emulation to use the generic distance
mechanism.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

With all memory configuration information now carried in numa_meminfo,
there's no need to keep mem_nodes_parsed separate.  Drop it and use
numa_nodes_parsed for CPU / memory-less nodes.

A new helper numa_nodemask_from_meminfo() is added to calculate
memnode mask on the fly which is currently used to set
node_possible_map.

This simplifies NUMA init methods a bit and removes a source of
possible inconsistencies.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

It's no longer necessary to keep both cpu_nodes_parsed and
mem_nodes_parsed.  In preparation for merge, rename cpu_nodes_parsed
to numa_nodes_parsed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

numa_nodes[] doesn't carry any information which isn't present in
numa_meminfo.  Each entry is simply min/max range of all the memblks
for the node.  This is not only redundant but also inaccurate when
memblks for different nodes interleave - for example,
find_node_by_addr() can return the wrong nodeid.

Kill numa_nodes[] and always use numa_meminfo instead.

* nodes_cover_memory() is renamed to numa_meminfo_cover_memory() and
  now operations on numa_meminfo and returns bool.

* setup_node_bootmem() needs min/max range.  Compute the range on the
  fly.  setup_node_bootmem() invocation is restructured to use outer
  loop instead of hardcoding the double invocations.

* find_node_by_addr() now operates on numa_meminfo.

* setup_physnodes() builds physnodes[] from memblks.  This will go
  away when emulation code is updated to use struct numa_meminfo.

This patch also makes the following misc changes.

* Clearing of nodes_add[] clearing is converted to memset().

* numa_add_memblk() in amd_numa_init() is moved down a bit for
  consistency.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

srat_64.c and amdtopology_64.c had their own versions of
find_node_by_addr() which were basically the same.  Add common one in
numa_64.c and remove the duplicates.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

memblk sanity check was scattered around and incomplete.  Consolidate
and improve.

* Confliction detection and cutoff_node() logic are moved to
  numa_cleanup_meminfo().

* numa_cleanup_meminfo() clears the unused memblks before returning.

* Check and warn about invalid input parameters in numa_add_memblk().

* Check the maximum number of memblk isn't exceeded in
  numa_add_memblk().

* numa_cleanup_meminfo() is now called before numa_emulation() so that
  the emulation code also uses the cleaned up version.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

* Factor out numa_remove_memblk_from().

* Hole detection doesn't need separate start/end.  Calculate start/end
  once.

* Relocate comment.

* Define iterators at the top and remove unnecessary prefix
  increments.

This prepares for further improvements to the function.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Separate out numa_cleanup_meminfo() from numa_register_memblks().
node_possible_map initialization is moved to the top of the split
numa_register_memblks().

This patch doesn't cause behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Arrays for memblks and nodeids and their length lived in separate
variables making things unnecessarily cumbersome.  Introduce struct
numa_meminfo which contains all memory configuration info.  This patch
doesn't cause any behavior change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

numa_emulation() called compute_hash_shift() with %NULL @nodeids which
meant identity mapping between index and nodeid.  Make
numa_emulation() build identity array and drop %NULL @nodeids handling
from populate_memnodemap() and thus from compute_hash_shift().  This
is to prepare for transition to using memblks instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

They are empty now.  Kill them.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Move the remaining memblk registration logic from acpi_scan_nodes() to
numa_register_memblks() and initmem_init().

This applies nodes_cover_memory() sanity check, memory node sorting
and node_online() checking, which were only applied to acpi, to all
init methods.

As all memblk registration is moved to common code, active range
clearing is moved to initmem_init() too and removed from bad_srat().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Make both amd and dummy use numa_add_memblk() to describe the detected
memory blocks.  This allows initmem_init() to call
numa_register_memblk() regardless of init method in use.  Drop custom
memory registration codes from amd and dummy.

After this change, memblk merge/cleanup in numa_register_memblks() is
applied to all init methods.

As this makes compute_hash_shift() and numa_register_memblks() used
only inside numa_64.c, make them static.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Factor out memblk handling from srat_64.c into two functions in
numa_64.c.  This patch doesn't introduce any behavior change.  The
next patch will make all init methods use these functions.

- v2: Fixed build failure on 32bit due to misplaced NR_NODE_MEMBLKS.
      Reported by Ingo.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

With common numa_nodes[], common code in numa_64.c can access it
directly.  Copy directly and kill {acpi|amd}_get_nodes().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

ACPI and amd are using separate nodes[] array.  Add numa_nodes[] and
use them in all NUMA init methods.  cutoff_node() cleanup is moved
from srat_64.c to numa_64.c and applied in initmem_init() regardless
of init methods.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

This brings amd initialization behavior closer to that of acpi.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Use weight count on mem_nodes_parsed instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

ACPI and amd are using separate nodes_parsed masks.  Add
{cpu|mem}_nodes_parsed and use them in all NUMA init methods.
Initialization of the masks and building node_possible_map are now
handled commonly by initmem_init().

dummy_numa_init() is updated to set node 0 on both masks.  While at
it, move the info messages from scan to init.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Reorganize initmem_init() such that,

* Different NUMA init methods are iterated in a consistent way.

* Each iteration re-initializes all the parameters and different
  method can be tried after a failure.

* Dummy init is handled the same as other methods.

Apart from how retry after failure, this patch doesn't change the
behavior.  The call sequences are kept equivalent across the
conversion.

After the change, bad_srat() doesn't need to clear apic to node
mapping or worry about numa_off.  Simplified accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

There's no reason for these to live in setup_arch().  Move them inside
initmem_init().

- v2: x86-32 initmem_init() weren't updated breaking 32bit builds.
  Fixed.  Found by Ankita.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ankita Garg <ankita@in.ibm.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Because of the way ACPI tables are parsed, the generic
acpi_numa_init() couldn't return failure when error was detected by
arch hooks.  Instead, the failure state was recorded and later arch
dependent init hook - acpi_scan_nodes() - would fail.

Wrap acpi_numa_init() with x86_acpi_numa_init() so that failure can be
indicated as return value immediately.  This is in preparation for
further NUMA init cleanups.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

The functions used during NUMA initialization - *_numa_init() and
*_scan_nodes() - have different arguments and return values.  Unify
them such that they all take no argument and return 0 on success and
-errno on failure.  This is in preparation for further NUMA init
cleanups.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

initmem_init() extensively accesses and modifies global data
structures and the parameters aren't even followed depending on which
path is being used.  Drop @start/last_pfn and let it deal with
@max_pfn directly.  This is in preparation for further NUMA init
cleanups.

- v2: x86-32 initmem_init() weren't updated breaking 32bit builds.
  Fixed.  Found by Yinghai.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Hotplug node handling in acpi_numa_memory_affinity_init() was
unnecessarily complicated with storing the original nodes[] entry and
restoring it afterwards.  Simplify it by not modifying the nodes[]
entry for hotplug nodes from the beginning.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Dummy node initialization in initmem_init() didn't initialize apicid
to node mapping and set cpu to node mapping directly by caling
numa_set_node(), which is different from non-dummy init paths.

Update it such that they behave similarly.  Initialize apicid to node
mapping and call numa_init_array().  The actual cpu to node mapping is
handled by init_cpu_to_node() later.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@linux.intel.com>

Merge reason: consolidate it into the more generic x86/mm tree to prevent conflicts
              with ongoing NUMA work.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge reason: consolidate it into the more generic x86/mm tree to prevent conflicts.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge reason: the topic is ready - consolidate it into the more generic x86/mm tree
              and prevent conflicts.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Commit d518573d ("x86, amd: Normalize compute unit IDs on
multi-node processors") introduced compute unit normalization
but causes a compiler warning:

 arch/x86/kernel/cpu/amd.c: In function 'amd_detect_cmp':
 arch/x86/kernel/cpu/amd.c:268: warning: 'cores_per_cu' may be used uninitialized in this function
 arch/x86/kernel/cpu/amd.c:268: note: 'cores_per_cu' was declared here

The compiler is right - initialize it with a proper value.

Also, fix up a comment while at it.
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
LKML-Reference: <20110214171451.GB10076@kryptos.osrc.amd.com>
Signed-off-by: Ingo 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: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: David 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: Ingo Molnar <mingo@elte.hu>

Merge reason: Merge latest fixes before applying new patch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Emit warning when "mem=nopentium" is specified on any arch other
than x86_32 (the only that arch supports it).
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
BugLink: http://bugs.launchpad.net/bugs/553464
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
LKML-Reference: <1296783486-23033-2-git-send-email-kamal@canonical.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>