linux.git/mm/memblock.c, branch v4.5

memblock: don't mark memblock_phys_mem_size() as __init

2016-02-06T02:10:40+00:00

At the moment memblock_phys_mem_size() is marked as __init, and so is
discarded after boot.  This is different from most of the memblock
functions which are marked __init_memblock, and are only discarded after
boot if memory hotplug is not configured.

To allow for upcoming code which will need memblock_phys_mem_size() in
the hotplug path, change it from __init to __init_memblock.

Signed-off-by: David Gibson 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock: introduce for_each_memblock_type()

2016-01-15T00:00:49+00:00

We already have the for_each_memblock() macro in 
which provides ability to iterate over memblock regions of a known type.
The for_each_memblock() macro allows us to pass the pointer to the
struct memblock_type, instead we need to pass name of the type.

This patch introduces a new macro for_each_memblock_type() which allows
us iterate over memblock regions with the given type when the type is
unknown.

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock: remove rgnbase and rgnsize variables

2016-01-15T00:00:49+00:00

Remove rgnbase and rgnsize variables from memblock_overlaps_region().
We use these variables only for passing to the memblock_addrs_overlap()
function and that's all.  Let's remove them.

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock.c: memblock_is_memory()/reserved() can be boolean

2016-01-15T00:00:49+00:00

Make memblock_is_memory() and memblock_is_reserved return bool to
improve readability due to these particular functions only using either
one or zero as their return value.

No functional change.

Signed-off-by: Yaowei Bai 
Acked-by: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock: add MEMBLOCK_NOMAP attribute to memblock memory table

2015-12-09T16:56:58+00:00

This introduces the MEMBLOCK_NOMAP attribute and the required plumbing
to make it usable as an indicator that some parts of normal memory
should not be covered by the kernel direct mapping. It is up to the
arch to actually honor the attribute when laying out this mapping,
but the memblock code itself is modified to disregard these regions
for allocations and other general use.

Cc: linux-mm@kvack.org
Cc: Alexander Kuleshov 
Cc: Andrew Morton 
Reviewed-by: Matt Fleming 
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Will Deacon

mm/memblock: make memblock_remove_range() static

2015-11-06T03:34:48+00:00

memblock_remove_range() is only used in the mm/memblock.c, so we can make
it static.

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock.c: fix comment in __next_mem_range()

2015-09-08T22:35:28+00:00

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock.c: fiy typos in comments

2015-09-08T22:35:28+00:00

s/succees/success/

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/memblock.c: rename local variable of memblock_type to 'type'

2015-09-08T22:35:28+00:00

Since commit e3239ff92a17 ("memblock: Rename memblock_region to
memblock_type and memblock_property to memblock_region"), all local
variables of the membock_type type were renamed to 'type'.  This commit
renames all remaining local variables with the memblock_type type to the
same view.

Signed-off-by: Alexander Kuleshov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mem-hotplug: handle node hole when initializing numa_meminfo.

2015-09-08T22:35:28+00:00

When parsing SRAT, all memory ranges are added into numa_meminfo.  In
numa_init(), before entering numa_cleanup_meminfo(), all possible memory
ranges are in numa_meminfo.  And numa_cleanup_meminfo() removes all
ranges over max_pfn or empty.

But, this only works if the nodes are continuous.  Let's have a look at
the following example:

We have an SRAT like this:
SRAT: Node 0 PXM 0 [mem 0x00000000-0x5fffffff]
SRAT: Node 0 PXM 0 [mem 0x100000000-0x1ffffffffff]
SRAT: Node 1 PXM 1 [mem 0x20000000000-0x3ffffffffff]
SRAT: Node 4 PXM 2 [mem 0x40000000000-0x5ffffffffff] hotplug
SRAT: Node 5 PXM 3 [mem 0x60000000000-0x7ffffffffff] hotplug
SRAT: Node 2 PXM 4 [mem 0x80000000000-0x9ffffffffff] hotplug
SRAT: Node 3 PXM 5 [mem 0xa0000000000-0xbffffffffff] hotplug
SRAT: Node 6 PXM 6 [mem 0xc0000000000-0xdffffffffff] hotplug
SRAT: Node 7 PXM 7 [mem 0xe0000000000-0xfffffffffff] hotplug

On boot, only node 0,1,2,3 exist.

And the numa_meminfo will look like this:
numa_meminfo.nr_blks = 9
1. on node 0: [0, 60000000]
2. on node 0: [100000000, 20000000000]
3. on node 1: [20000000000, 40000000000]
4. on node 4: [40000000000, 60000000000]
5. on node 5: [60000000000, 80000000000]
6. on node 2: [80000000000, a0000000000]
7. on node 3: [a0000000000, a0800000000]
8. on node 6: [c0000000000, a0800000000]
9. on node 7: [e0000000000, a0800000000]

And numa_cleanup_meminfo() will merge 1 and 2, and remove 8,9 because the
end address is over max_pfn, which is a0800000000.  But 4 and 5 are not
removed because their end addresses are less then max_pfn.  But in fact,
node 4 and 5 don't exist.

In a word, numa_cleanup_meminfo() is not able to handle holes between nodes.

Since memory ranges in node 4 and 5 are in numa_meminfo, in
numa_register_memblks(), node 4 and 5 will be mistakenly set to online.

If you run lscpu, it will show:
NUMA node0 CPU(s):     0-14,128-142
NUMA node1 CPU(s):     15-29,143-157
NUMA node2 CPU(s):
NUMA node3 CPU(s):
NUMA node4 CPU(s):     62-76,190-204
NUMA node5 CPU(s):     78-92,206-220

In this patch, we use memblock_overlaps_region() to check if ranges in
numa_meminfo overlap with ranges in memory_block.  Since memory_block
contains all available memory at boot time, if they overlap, it means the
ranges exist.  If not, then remove them from numa_meminfo.

After this patch, lscpu will show:
NUMA node0 CPU(s):     0-14,128-142
NUMA node1 CPU(s):     15-29,143-157
NUMA node4 CPU(s):     62-76,190-204
NUMA node5 CPU(s):     78-92,206-220

Signed-off-by: Tang Chen 
Reviewed-by: Yasuaki Ishimatsu 
Cc: Thomas Gleixner 
Cc: Tejun Heo 
Cc: Luiz Capitulino 
Cc: Xishi Qiu 
Cc: Will Deacon 
Cc: Vladimir Murzin 
Cc: Fabian Frederick 
Cc: Alexander Kuleshov 
Cc: Baoquan He 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds