Commit Graph

169 Commits

Author SHA1 Message Date
Wei Yang
d538c164fc mm/sparse.c: check __highest_present_section_nr only for a present section
When searching a present section, there are two boundaries:

    * __highest_present_section_nr
    * NR_MEM_SECTIONS

And it is known, __highest_present_section_nr is a more strict boundary
than NR_MEM_SECTIONS.  This means it would be necessary to check
__highest_present_section_nr only.

Link: http://lkml.kernel.org/r/20180326081956.75275-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00
Pavel Tatashin
27227c7338 mm: sections are not offlined during memory hotremove
Memory hotplug and hotremove operate with per-block granularity.  If the
machine has a large amount of memory (more than 64G), the size of a
memory block can span multiple sections.  By mistake, during hotremove
we set only the first section to offline state.

The bug was discovered because kernel selftest started to fail:
  https://lkml.kernel.org/r/20180423011247.GK5563@yexl-desktop

After commit, "mm/memory_hotplug: optimize probe routine".  But, the bug
is older than this commit.  In this optimization we also added a check
for sections to be in a proper state during hotplug operation.

Link: http://lkml.kernel.org/r/20180427145257.15222-1-pasha.tatashin@oracle.com
Fixes: 2d070eab2e ("mm: consider zone which is not fully populated to have holes")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-11 17:28:45 -07:00
Pavel Tatashin
d0dc12e86b mm/memory_hotplug: optimize memory hotplug
During memory hotplugging we traverse struct pages three times:

1. memset(0) in sparse_add_one_section()
2. loop in __add_section() to set do: set_page_node(page, nid); and
   SetPageReserved(page);
3. loop in memmap_init_zone() to call __init_single_pfn()

This patch removes the first two loops, and leaves only loop 3.  All
struct pages are initialized in one place, the same as it is done during
boot.

The benefits:

 - We improve memory hotplug performance because we are not evicting the
   cache several times and also reduce loop branching overhead.

 - Remove condition from hotpath in __init_single_pfn(), that was added
   in order to fix the problem that was reported by Bharata in the above
   email thread, thus also improve performance during normal boot.

 - Make memory hotplug more similar to the boot memory initialization
   path because we zero and initialize struct pages only in one
   function.

 - Simplifies memory hotplug struct page initialization code, and thus
   enables future improvements, such as multi-threading the
   initialization of struct pages in order to improve hotplug
   performance even further on larger machines.

[pasha.tatashin@oracle.com: v5]
  Link: http://lkml.kernel.org/r/20180228030308.1116-7-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180215165920.8570-7-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:25 -07:00
Linus Torvalds
f5a8eb632b arch: remove obsolete architecture ports
This removes the entire architecture code for blackfin, cris, frv, m32r,
 metag, mn10300, score, and tile, including the associated device drivers.
 
 I have been working with the (former) maintainers for each one to ensure
 that my interpretation was right and the code is definitely unused in
 mainline kernels. Many had fond memories of working on the respective
 ports to start with and getting them included in upstream, but also saw
 no point in keeping the port alive without any users.
 
 In the end, it seems that while the eight architectures are extremely
 different, they all suffered the same fate: There was one company
 in charge of an SoC line, a CPU microarchitecture and a software
 ecosystem, which was more costly than licensing newer off-the-shelf
 CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems
 that all the SoC product lines are still around, but have not used the
 custom CPU architectures for several years at this point. In contrast,
 CPU instruction sets that remain popular and have actively maintained
 kernel ports tend to all be used across multiple licensees.
 
 The removal came out of a discussion that is now documented at
 https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
 marking any ports as deprecated but remove them all at once after I made
 sure that they are all unused. Some architectures (notably tile, mn10300,
 and blackfin) are still being shipped in products with old kernels,
 but those products will never be updated to newer kernel releases.
 
 After this series, we still have a few architectures without mainline
 gcc support:
 
 - unicore32 and hexagon both have very outdated gcc releases, but the
   maintainers promised to work on providing something newer. At least
   in case of hexagon, this will only be llvm, not gcc.
 
 - openrisc, risc-v and nds32 are still in the process of finishing their
   support or getting it added to mainline gcc in the first place.
   They all have patched gcc-7.3 ports that work to some degree, but
   complete upstream support won't happen before gcc-8.1. Csky posted
   their first kernel patch set last week, their situation will be similar.
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Merge tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pul removal of obsolete architecture ports from Arnd Bergmann:
 "This removes the entire architecture code for blackfin, cris, frv,
  m32r, metag, mn10300, score, and tile, including the associated device
  drivers.

  I have been working with the (former) maintainers for each one to
  ensure that my interpretation was right and the code is definitely
  unused in mainline kernels. Many had fond memories of working on the
  respective ports to start with and getting them included in upstream,
  but also saw no point in keeping the port alive without any users.

  In the end, it seems that while the eight architectures are extremely
  different, they all suffered the same fate: There was one company in
  charge of an SoC line, a CPU microarchitecture and a software
  ecosystem, which was more costly than licensing newer off-the-shelf
  CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
  seems that all the SoC product lines are still around, but have not
  used the custom CPU architectures for several years at this point. In
  contrast, CPU instruction sets that remain popular and have actively
  maintained kernel ports tend to all be used across multiple licensees.

  [ See the new nds32 port merged in the previous commit for the next
    generation of "one company in charge of an SoC line, a CPU
    microarchitecture and a software ecosystem"   - Linus ]

  The removal came out of a discussion that is now documented at
  https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
  marking any ports as deprecated but remove them all at once after I
  made sure that they are all unused. Some architectures (notably tile,
  mn10300, and blackfin) are still being shipped in products with old
  kernels, but those products will never be updated to newer kernel
  releases.

  After this series, we still have a few architectures without mainline
  gcc support:

   - unicore32 and hexagon both have very outdated gcc releases, but the
     maintainers promised to work on providing something newer. At least
     in case of hexagon, this will only be llvm, not gcc.

   - openrisc, risc-v and nds32 are still in the process of finishing
     their support or getting it added to mainline gcc in the first
     place. They all have patched gcc-7.3 ports that work to some
     degree, but complete upstream support won't happen before gcc-8.1.
     Csky posted their first kernel patch set last week, their situation
     will be similar

  [ Palmer Dabbelt points out that RISC-V support is in mainline gcc
    since gcc-7, although gcc-7.3.0 is the recommended minimum  - Linus ]"

This really says it all:

 2498 files changed, 95 insertions(+), 467668 deletions(-)

* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
  MAINTAINERS: UNICORE32: Change email account
  staging: iio: remove iio-trig-bfin-timer driver
  tty: hvc: remove tile driver
  tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
  serial: remove tile uart driver
  serial: remove m32r_sio driver
  serial: remove blackfin drivers
  serial: remove cris/etrax uart drivers
  usb: Remove Blackfin references in USB support
  usb: isp1362: remove blackfin arch glue
  usb: musb: remove blackfin port
  usb: host: remove tilegx platform glue
  pwm: remove pwm-bfin driver
  i2c: remove bfin-twi driver
  spi: remove blackfin related host drivers
  watchdog: remove bfin_wdt driver
  can: remove bfin_can driver
  mmc: remove bfin_sdh driver
  input: misc: remove blackfin rotary driver
  input: keyboard: remove bf54x driver
  ...
2018-04-02 20:20:12 -07:00
David Rientjes
fc5d1073ca x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic
node_memmap_size_bytes() has been unused since the v3.9 kernel, so remove it.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: f03574f2d5 ("x86-32, mm: Rip out x86_32 NUMA remapping code")
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1803262325540.256524@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27 08:45:02 +02:00
Arnd Bergmann
79375ea3ec mm: remove obsolete alloc_remap()
Tile was the only remaining architecture to implement alloc_remap(),
and since that is being removed, there is no point in keeping this
function.

Removing all callers simplifies the mem_map handling.

Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-16 10:56:13 +01:00
Linus Torvalds
3ff1b28caa libnvdimm for 4.16
* Require struct page by default for filesystem DAX to remove a number of
   surprising failure cases.  This includes failures with direct I/O, gdb and
   fork(2).
 
 * Add support for the new Platform Capabilities Structure added to the NFIT in
   ACPI 6.2a.  This new table tells us whether the platform supports flushing
   of CPU and memory controller caches on unexpected power loss events.
 
 * Revamp vmem_altmap and dev_pagemap handling to clean up code and better
   support future future PCI P2P uses.
 
 * Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has become
   out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL spec, and
   instead rely on the generic ND_CMD_CALL approach used by the two other IOCTL
   families, NVDIMM_FAMILY_{HPE,MSFT}.
 
 * Enhance nfit_test so we can test some of the new things added in version 1.6
   of the DSM specification.  This includes testing firmware download and
   simulating the Last Shutdown State (LSS) status.
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Merge tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Ross Zwisler:

 - Require struct page by default for filesystem DAX to remove a number
   of surprising failure cases. This includes failures with direct I/O,
   gdb and fork(2).

 - Add support for the new Platform Capabilities Structure added to the
   NFIT in ACPI 6.2a. This new table tells us whether the platform
   supports flushing of CPU and memory controller caches on unexpected
   power loss events.

 - Revamp vmem_altmap and dev_pagemap handling to clean up code and
   better support future future PCI P2P uses.

 - Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has
   become out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL
   spec, and instead rely on the generic ND_CMD_CALL approach used by
   the two other IOCTL families, NVDIMM_FAMILY_{HPE,MSFT}.

 - Enhance nfit_test so we can test some of the new things added in
   version 1.6 of the DSM specification. This includes testing firmware
   download and simulating the Last Shutdown State (LSS) status.

* tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (37 commits)
  libnvdimm, namespace: remove redundant initialization of 'nd_mapping'
  acpi, nfit: fix register dimm error handling
  libnvdimm, namespace: make min namespace size 4K
  tools/testing/nvdimm: force nfit_test to depend on instrumented modules
  libnvdimm/nfit_test: adding support for unit testing enable LSS status
  libnvdimm/nfit_test: add firmware download emulation
  nfit-test: Add platform cap support from ACPI 6.2a to test
  libnvdimm: expose platform persistence attribute for nd_region
  acpi: nfit: add persistent memory control flag for nd_region
  acpi: nfit: Add support for detect platform CPU cache flush on power loss
  device-dax: Fix trailing semicolon
  libnvdimm, btt: fix uninitialized err_lock
  dax: require 'struct page' by default for filesystem dax
  ext2: auto disable dax instead of failing mount
  ext4: auto disable dax instead of failing mount
  mm, dax: introduce pfn_t_special()
  mm: Fix devm_memremap_pages() collision handling
  mm: Fix memory size alignment in devm_memremap_pages_release()
  memremap: merge find_dev_pagemap into get_dev_pagemap
  memremap: change devm_memremap_pages interface to use struct dev_pagemap
  ...
2018-02-06 10:41:33 -08:00
Ross Zwisler
ee95f4059a Merge branch 'for-4.16/nfit' into libnvdimm-for-next 2018-02-03 00:26:26 -07:00
Petr Tesarik
def9b71ee6 include/linux/mmzone.h: fix explanation of lower bits in the SPARSEMEM mem_map pointer
The comment is confusing.  On the one hand, it refers to 32-bit
alignment (struct page alignment on 32-bit platforms), but this would
only guarantee that the 2 lowest bits must be zero.  On the other hand,
it claims that at least 3 bits are available, and 3 bits are actually
used.

This is not broken, because there is a stronger alignment guarantee,
just less obvious.  Let's fix the comment to make it clear how many bits
are available and why.

Although memmap arrays are allocated in various places, the resulting
pointer is encoded eventually, so I am adding a BUG_ON() here to enforce
at runtime that all expected bits are indeed available.

I have also added a BUILD_BUG_ON to check that PFN_SECTION_SHIFT is
sufficient, because this part of the calculation can be easily checked
at build time.

[ptesarik@suse.com: v2]
  Link: http://lkml.kernel.org/r/20180125100516.589ea6af@ezekiel.suse.cz
Link: http://lkml.kernel.org/r/20180119080908.3a662e6f@ezekiel.suse.cz
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 17:18:39 -08:00
Christoph Hellwig
24b6d41643 mm: pass the vmem_altmap to vmemmap_free
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig
7b73d978a5 mm: pass the vmem_altmap to vmemmap_populate
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Baoquan He
d09cfbbfa0 mm/sparse.c: wrong allocation for mem_section
In commit 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime
for CONFIG_SPARSEMEM_EXTREME=y") mem_section is allocated at runtime to
save memory.

It allocates the first dimension of array with sizeof(struct mem_section).

It costs extra memory, should be sizeof(struct mem_section *).

Fix it.

Link: http://lkml.kernel.org/r/1513932498-20350-1-git-send-email-bhe@redhat.com
Fixes: 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Signed-off-by: Baoquan He <bhe@redhat.com>
Tested-by: Dave Young <dyoung@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Atsushi Kumagai <ats-kumagai@wm.jp.nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-04 16:45:09 -08:00
Pavel Tatashin
f7f99100d8 mm: stop zeroing memory during allocation in vmemmap
vmemmap_alloc_block() will no longer zero the block, so zero memory at
its call sites for everything except struct pages.  Struct page memory
is zero'd by struct page initialization.

Replace allocators in sparse-vmemmap to use the non-zeroing version.
So, we will get the performance improvement by zeroing the memory in
parallel when struct pages are zeroed.

Add struct page zeroing as a part of initialization of other fields in
__init_single_page().

This single thread performance collected on: Intel(R) Xeon(R) CPU E7-8895
v3 @ 2.60GHz with 1T of memory (268400646 pages in 8 nodes):

                         BASE            FIX
sparse_init     11.244671836s   0.007199623s
zone_sizes_init  4.879775891s   8.355182299s
                  --------------------------
Total           16.124447727s   8.362381922s

sparse_init is where memory for struct pages is zeroed, and the zeroing
part is moved later in this patch into __init_single_page(), which is
called from zone_sizes_init().

[akpm@linux-foundation.org: make vmemmap_alloc_block_zero() private to sparse-vmemmap.c]
Link: http://lkml.kernel.org/r/20171013173214.27300-10-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:05 -08:00
Ingo Molnar
d04fdafc06 Merge branch 'x86/mm' into x86/asm, to merge branches
Most of x86/mm is already in x86/asm, so merge the rest too.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-10 08:05:30 +01:00
Kirill A. Shutemov
629a359bdb mm/sparsemem: Fix ARM64 boot crash when CONFIG_SPARSEMEM_EXTREME=y
Since commit:

  83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")

we allocate the mem_section array dynamically in sparse_memory_present_with_active_regions(),
but some architectures, like arm64, don't call the routine to initialize sparsemem.

Let's move the initialization into memory_present() it should cover all
architectures.

Reported-and-tested-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Fixes: 83e3c48729 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Link: http://lkml.kernel.org/r/20171107083337.89952-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 11:16:08 +01:00
Ingo Molnar
b3d9a13681 Merge branch 'linus' into x86/asm, to pick up fixes and resolve conflicts
Conflicts:
	arch/x86/kernel/cpu/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:53:06 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Kirill A. Shutemov
83e3c48729 mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y
Size of the mem_section[] array depends on the size of the physical address space.

In preparation for boot-time switching between paging modes on x86-64
we need to make the allocation of mem_section[] dynamic, because otherwise
we waste a lot of RAM: with CONFIG_NODE_SHIFT=10, mem_section[] size is 32kB
for 4-level paging and 2MB for 5-level paging mode.

The patch allocates the array on the first call to sparse_memory_present_with_active_regions().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170929140821.37654-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-20 13:07:09 +02:00
Michal Hocko
b4ccec41af mm/sparse.c: fix typo in online_mem_sections
online_mem_sections() accidentally marks online only the first section
in the given range.  This is a typo which hasn't been noticed because I
haven't tested large 2GB blocks previously.  All users of
pfn_to_online_page would get confused on the the rest of the pfn range
in the block.

All we need to fix this is to use iterator (pfn) rather than start_pfn.

Link: http://lkml.kernel.org/r/20170904112210.3401-1-mhocko@kernel.org
Fixes: 2d070eab2e ("mm: consider zone which is not fully populated to have holes")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:47 -07:00
Michal Hocko
b95046b047 mm, sparse, page_ext: drop ugly N_HIGH_MEMORY branches for allocations
Commit f52407ce2d ("memory hotplug: alloc page from other node in
memory online") has introduced N_HIGH_MEMORY checks to only use NUMA
aware allocations when there is some memory present because the
respective node might not have any memory yet at the time and so it
could fail or even OOM.

Things have changed since then though.  Zonelists are now always
initialized before we do any allocations even for hotplug (see
959ecc48fc ("mm/memory_hotplug.c: fix building of node hotplug
zonelist")).

Therefore these checks are not really needed.  In fact caller of the
allocator should never care about whether the node is populated because
that might change at any time.

Link: http://lkml.kernel.org/r/20170721143915.14161-10-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
Michal Hocko
f1dd2cd13c mm, memory_hotplug: do not associate hotadded memory to zones until online
The current memory hotplug implementation relies on having all the
struct pages associate with a zone/node during the physical hotplug
phase (arch_add_memory->__add_pages->__add_section->__add_zone).  In the
vast majority of cases this means that they are added to ZONE_NORMAL.
This has been so since 9d99aaa31f ("[PATCH] x86_64: Support memory
hotadd without sparsemem") and it wasn't a big deal back then because
movable onlining didn't exist yet.

Much later memory hotplug wanted to (ab)use ZONE_MOVABLE for movable
onlining 511c2aba8f ("mm, memory-hotplug: dynamic configure movable
memory and portion memory") and then things got more complicated.
Rather than reconsidering the zone association which was no longer
needed (because the memory hotplug already depended on SPARSEMEM) a
convoluted semantic of zone shifting has been developed.  Only the
currently last memblock or the one adjacent to the zone_movable can be
onlined movable.  This essentially means that the online type changes as
the new memblocks are added.

Let's simulate memory hot online manually
  $ echo 0x100000000 > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory32/valid_zones
  Normal Movable

  $ echo $((0x100000000+(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  $ echo $((0x100000000+2*(128<<20))) > /sys/devices/system/memory/probe
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  $ echo online_movable > /sys/devices/system/memory/memory34/state
  $ grep . /sys/devices/system/memory/memory3?/valid_zones
  /sys/devices/system/memory/memory32/valid_zones:Normal
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable Normal

This is an awkward semantic because an udev event is sent as soon as the
block is onlined and an udev handler might want to online it based on
some policy (e.g.  association with a node) but it will inherently race
with new blocks showing up.

This patch changes the physical online phase to not associate pages with
any zone at all.  All the pages are just marked reserved and wait for
the onlining phase to be associated with the zone as per the online
request.  There are only two requirements

	- existing ZONE_NORMAL and ZONE_MOVABLE cannot overlap

	- ZONE_NORMAL precedes ZONE_MOVABLE in physical addresses

the latter one is not an inherent requirement and can be changed in the
future.  It preserves the current behavior and made the code slightly
simpler.  This is subject to change in future.

This means that the same physical online steps as above will lead to the
following state: Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Normal Movable

  /sys/devices/system/memory/memory32/valid_zones:Normal Movable
  /sys/devices/system/memory/memory33/valid_zones:Normal Movable
  /sys/devices/system/memory/memory34/valid_zones:Movable

Implementation:
The current move_pfn_range is reimplemented to check the above
requirements (allow_online_pfn_range) and then updates the respective
zone (move_pfn_range_to_zone), the pgdat and links all the pages in the
pfn range with the zone/node.  __add_pages is updated to not require the
zone and only initializes sections in the range.  This allowed to
simplify the arch_add_memory code (s390 could get rid of quite some of
code).

devm_memremap_pages is the only user of arch_add_memory which relies on
the zone association because it only hooks into the memory hotplug only
half way.  It uses it to associate the new memory with ZONE_DEVICE but
doesn't allow it to be {on,off}lined via sysfs.  This means that this
particular code path has to call move_pfn_range_to_zone explicitly.

The original zone shifting code is kept in place and will be removed in
the follow up patch for an easier review.

Please note that this patch also changes the original behavior when
offlining a memory block adjacent to another zone (Normal vs.  Movable)
used to allow to change its movable type.  This will be handled later.

[richard.weiyang@gmail.com: simplify zone_intersects()]
  Link: http://lkml.kernel.org/r/20170616092335.5177-1-richard.weiyang@gmail.com
[richard.weiyang@gmail.com: remove duplicate call for set_page_links]
  Link: http://lkml.kernel.org/r/20170616092335.5177-2-richard.weiyang@gmail.com
[akpm@linux-foundation.org: remove unused local `i']
Link: http://lkml.kernel.org/r/20170515085827.16474-12-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # For s390 bits
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Michal Hocko
2d070eab2e mm: consider zone which is not fully populated to have holes
__pageblock_pfn_to_page has two users currently, set_zone_contiguous
which checks whether the given zone contains holes and
pageblock_pfn_to_page which then carefully returns a first valid page
from the given pfn range for the given zone.  This doesn't handle zones
which are not fully populated though.  Memory pageblocks can be offlined
or might not have been onlined yet.  In such a case the zone should be
considered to have holes otherwise pfn walkers can touch and play with
offline pages.

Current callers of pageblock_pfn_to_page in compaction seem to work
properly right now because they only isolate PageBuddy
(isolate_freepages_block) or PageLRU resp.  __PageMovable
(isolate_migratepages_block) which will be always false for these pages.
It would be safer to skip these pages altogether, though.

In order to do this patch adds a new memory section state
(SECTION_IS_ONLINE) which is set in memory_present (during boot time) or
in online_pages_range during the memory hotplug.  Similarly
offline_mem_sections clears the bit and it is called when the memory
range is offlined.

pfn_to_online_page helper is then added which check the mem section and
only returns a page if it is onlined already.

Use the new helper in __pageblock_pfn_to_page and skip the whole page
block in such a case.

[mhocko@suse.com: check valid section number in pfn_to_online_page (Vlastimil),
 mark sections online after all struct pages are initialized in
 online_pages_range (Vlastimil)]
  Link: http://lkml.kernel.org/r/20170518164210.GD18333@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/20170515085827.16474-8-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Daniel Kiper <daniel.kiper@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:32 -07:00
Dave Hansen
c4e1be9ec1 mm, sparsemem: break out of loops early
There are a number of times that we loop over NR_MEM_SECTIONS, looking
for section_present() on each section.  But, when we have very large
physical address spaces (large MAX_PHYSMEM_BITS), NR_MEM_SECTIONS
becomes very large, making the loops quite long.

With MAX_PHYSMEM_BITS=46 and a section size of 128MB, the current loops
are 512k iterations, which we barely notice on modern hardware.  But,
raising MAX_PHYSMEM_BITS higher (like we will see on systems that
support 5-level paging) makes this 64x longer and we start to notice,
especially on slower systems like simulators.  A 10-second delay for
512k iterations is annoying.  But, a 640- second delay is crippling.

This does not help if we have extremely sparse physical address spaces,
but those are quite rare.  We expect that most of the "slow" systems
where this matters will also be quite small and non-sparse.

To fix this, we track the highest section we've ever encountered.  This
lets us know when we will *never* see another section_present(), and
lets us break out of the loops earlier.

Doing the whole for_each_present_section_nr() macro is probably
overkill, but it will ensure that any future loop iterations that we
grow are more likely to be correct.

Kirrill said "It shaved almost 40 seconds from boot time in qemu with
5-level paging enabled for me".

Link: http://lkml.kernel.org/r/20170504174434.C45A4735@viggo.jf.intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:31 -07:00
Wei Yang
60a7a88dbb mm/sparse: refine usemap_size() a little
The current implementation calculates usemap_size in two steps:
    * calculate number of bytes to cover these bits
    * calculate number of "unsigned long" to cover these bytes

It would be more clear by:
    * calculate number of "unsigned long" to cover these bits
    * multiple it with sizeof(unsigned long)

This patch refine usemap_size() a little to make it more easy to
understand.

Link: http://lkml.kernel.org/r/20170310043713.96871-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-03 15:52:09 -07:00
Yasuaki Ishimatsu
ddffe98d16 mm/memory_hotplug: set magic number to page->freelist instead of page->lru.next
To identify that pages of page table are allocated from bootmem
allocator, magic number sets to page->lru.next.

But page->lru list is initialized in reserve_bootmem_region().  So when
calling free_pagetable(), the function cannot find the magic number of
pages.  And free_pagetable() frees the pages by free_reserved_page() not
put_page_bootmem().

But if the pages are allocated from bootmem allocator and used as page
table, the pages have private flag.  So before freeing the pages, we
should clear the private flag by put_page_bootmem().

Before applying the commit 7bfec6f47b ("mm, page_alloc: check multiple
page fields with a single branch"), we could find the following visible
issue:

  BUG: Bad page state in process kworker/u1024:1
  page:ffffea103cfd8040 count:0 mapcount:0 mappi
  flags: 0x6fffff80000800(private)
  page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
  bad because of flags: 0x800(private)
  <snip>
  Call Trace:
  [...] dump_stack+0x63/0x87
  [...] bad_page+0x114/0x130
  [...] free_pages_prepare+0x299/0x2d0
  [...] free_hot_cold_page+0x31/0x150
  [...] __free_pages+0x25/0x30
  [...] free_pagetable+0x6f/0xb4
  [...] remove_pagetable+0x379/0x7ff
  [...] vmemmap_free+0x10/0x20
  [...] sparse_remove_one_section+0x149/0x180
  [...] __remove_pages+0x2e9/0x4f0
  [...] arch_remove_memory+0x63/0xc0
  [...] remove_memory+0x8c/0xc0
  [...] acpi_memory_device_remove+0x79/0xa5
  [...] acpi_bus_trim+0x5a/0x8d
  [...] acpi_bus_trim+0x38/0x8d
  [...] acpi_device_hotplug+0x1b7/0x418
  [...] acpi_hotplug_work_fn+0x1e/0x29
  [...] process_one_work+0x152/0x400
  [...] worker_thread+0x125/0x4b0
  [...] kthread+0xd8/0xf0
  [...] ret_from_fork+0x22/0x40

And the issue still silently occurs.

Until freeing the pages of page table allocated from bootmem allocator,
the page->freelist is never used.  So the patch sets magic number to
page->freelist instead of page->lru.next.

[isimatu.yasuaki@jp.fujitsu.com: fix merge issue]
  Link: http://lkml.kernel.org/r/722b1cc4-93ac-dd8b-2be2-7a7e313b3b0b@gmail.com
Link: http://lkml.kernel.org/r/2c29bd9f-5b67-02d0-18a3-8828e78bbb6f@gmail.com
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22 16:41:29 -08:00
Yasuaki Ishimatsu
857e522a00 mm/sparse: use page_private() to get page->private value
free_map_bootmem() uses page->private directly to set
removing_section_nr argument.  But to get page->private value,
page_private() has been prepared.

So free_map_bootmem() should use page_private() instead of
page->private.

Link: http://lkml.kernel.org/r/1d34eaa5-a506-8b7a-6471-490c345deef8@gmail.com
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22 16:41:29 -08:00
Fabian Frederick
bd721ea73e treewide: replace obsolete _refok by __ref
There was only one use of __initdata_refok and __exit_refok

__init_refok was used 46 times against 82 for __ref.

Those definitions are obsolete since commit 312b1485fb ("Introduce new
section reference annotations tags: __ref, __refdata, __refconst")

This patch removes the following compatibility definitions and replaces
them treewide.

/* compatibility defines */
#define __init_refok     __ref
#define __initdata_refok __refdata
#define __exit_refok     __ref

I can also provide separate patches if necessary.
(One patch per tree and check in 1 month or 2 to remove old definitions)

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 17:31:41 -04:00
Zhou Chengming
91fd8b95d6 make __section_nr() more efficient
When CONFIG_SPARSEMEM_EXTREME is disabled, __section_nr can get the
section number with a subtraction directly.

Link: http://lkml.kernel.org/r/1468988310-11560-1-git-send-email-zhouchengming1@huawei.com
Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Li Bin <huawei.libin@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28 16:07:41 -07:00
Joe Perches
1170532bb4 mm: convert printk(KERN_<LEVEL> to pr_<level>
Most of the mm subsystem uses pr_<level> so make it consistent.

Miscellanea:

 - Realign arguments
 - Add missing newline to format
 - kmemleak-test.c has a "kmemleak: " prefix added to the
   "Kmemleak testing" logging message via pr_fmt

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>	[percpu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Joe Perches
756a025f00 mm: coalesce split strings
Kernel style prefers a single string over split strings when the string is
'user-visible'.

Miscellanea:

 - Add a missing newline
 - Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>	[percpu]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Dan Williams
4b94ffdc41 x86, mm: introduce vmem_altmap to augment vmemmap_populate()
In support of providing struct page for large persistent memory
capacities, use struct vmem_altmap to change the default policy for
allocating memory for the memmap array.  The default vmemmap_populate()
allocates page table storage area from the page allocator.  Given
persistent memory capacities relative to DRAM it may not be feasible to
store the memmap in 'System Memory'.  Instead vmem_altmap represents
pre-allocated "device pages" to satisfy vmemmap_alloc_block_buf()
requests.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
Gideon Israel Dsouza
3b32123d73 mm: use macros from compiler.h instead of __attribute__((...))
To increase compiler portability there is <linux/compiler.h> which
provides convenience macros for various gcc constructs.  Eg: __weak for
__attribute__((weak)).  I've replaced all instances of gcc attributes with
the right macro in the memory management (/mm) subsystem.

[akpm@linux-foundation.org: while-we're-there consistency tweaks]
Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:35:54 -07:00
Li Zhong
c800bcd5f5 sparse: fix comment
retmain -> remain

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-04-02 09:16:17 +02:00
Santosh Shilimkar
bb016b8416 mm/sparse: use memblock apis for early memory allocations
Switch to memblock interfaces for early memory allocator instead of
bootmem allocator.  No functional change in beahvior than what it is in
current code from bootmem users points of view.

Archs already converted to NO_BOOTMEM now directly use memblock
interfaces instead of bootmem wrappers build on top of memblock.  And
the archs which still uses bootmem, these new apis just fallback to
exiting bootmem APIs.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21 16:19:47 -08:00
Zhang Yanfei
81556b0252 mm/sparsemem: fix a bug in free_map_bootmem when CONFIG_SPARSEMEM_VMEMMAP
We pass the number of pages which hold page structs of a memory section
to free_map_bootmem().  This is right when !CONFIG_SPARSEMEM_VMEMMAP but
wrong when CONFIG_SPARSEMEM_VMEMMAP.  When CONFIG_SPARSEMEM_VMEMMAP, we
should pass the number of pages of a memory section to free_map_bootmem.

So the fix is removing the nr_pages parameter.  When
CONFIG_SPARSEMEM_VMEMMAP, we directly use the prefined marco
PAGES_PER_SECTION in free_map_bootmem.  When !CONFIG_SPARSEMEM_VMEMMAP,
we calculate page numbers needed to hold the page structs for a memory
section and use the value in free_map_bootmem().

This was found by reading the code.  And I have no machine that support
memory hot-remove to test the bug now.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:06 +09:00
Zhang Yanfei
85b35feaec mm/sparsemem: use PAGES_PER_SECTION to remove redundant nr_pages parameter
For below functions,

- sparse_add_one_section()
- kmalloc_section_memmap()
- __kmalloc_section_memmap()
- __kfree_section_memmap()

they are always invoked to operate on one memory section, so it is
redundant to always pass a nr_pages parameter, which is the page numbers
in one section.  So we can directly use predefined macro PAGES_PER_SECTION
instead of passing the parameter.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:06 +09:00
Wanpeng Li
187320932d mm/sparse: introduce alloc_usemap_and_memmap
After commit 9bdac91424 ("sparsemem: Put mem map for one node
together."), vmemmap for one node will be allocated together, its logic
is similar as memory allocation for pageblock flags.  This patch
introduces alloc_usemap_and_memmap to extract the same logic of memory
alloction for pageblock flags and vmemmap.

Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:58:01 -07:00
Zhang Yanfei
f3deb6872b mm/sparse.c: put clear_hwpoisoned_pages within CONFIG_MEMORY_HOTREMOVE
With CONFIG_MEMORY_HOTREMOVE unset, there is a compile warning:

  mm/sparse.c:755: warning: `clear_hwpoisoned_pages' defined but not used

And Bisecting it ended up pointing to 4edd7ceff ("mm, hotplug: avoid
compiling memory hotremove functions when disabled").

This is because the commit above put sparse_remove_one_section() within
the protection of CONFIG_MEMORY_HOTREMOVE but the only user of
clear_hwpoisoned_pages() is sparse_remove_one_section(), and it is not
within the protection of CONFIG_MEMORY_HOTREMOVE.

So put clear_hwpoisoned_pages within CONFIG_MEMORY_HOTREMOVE should fix
the warning.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:22 -07:00
Linus Torvalds
80cc38b163 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  treewide: relase -> release
  Documentation/cgroups/memory.txt: fix stat file documentation
  sysctl/net.txt: delete reference to obsolete 2.4.x kernel
  spinlock_api_smp.h: fix preprocessor comments
  treewide: Fix typo in printk
  doc: device tree: clarify stuff in usage-model.txt.
  open firmware: "/aliasas" -> "/aliases"
  md: bcache: Fixed a typo with the word 'arithmetic'
  irq/generic-chip: fix a few kernel-doc entries
  frv: Convert use of typedef ctl_table to struct ctl_table
  sgi: xpc: Convert use of typedef ctl_table to struct ctl_table
  doc: clk: Fix incorrect wording
  Documentation/arm/IXP4xx fix a typo
  Documentation/networking/ieee802154 fix a typo
  Documentation/DocBook/media/v4l fix a typo
  Documentation/video4linux/si476x.txt fix a typo
  Documentation/virtual/kvm/api.txt fix a typo
  Documentation/early-userspace/README fix a typo
  Documentation/video4linux/soc-camera.txt fix a typo
  lguest: fix CONFIG_PAE -> CONFIG_x86_PAE in comment
  ...
2013-07-04 11:40:58 -07:00
Cody P Schafer
55878e88c5 sparsemem: add BUILD_BUG_ON when sizeof mem_section is non-power-of-2
Instead of leaving a hidden trap for the next person who comes along and
wants to add something to mem_section, add a big fat warning about it
needing to be a power-of-2, and insert a BUILD_BUG_ON() in sparse_init()
to catch mistakes.

Right now non-power-of-2 mem_sections cause a number of WARNs at boot
(which don't clearly point to the size of mem_section as an issue), but
the system limps on (temporarily, at least).

This is based upon Dave Hansen's earlier RFC where he ran into the same
issue:
	"sparsemem: fix boot when SECTIONS_PER_ROOT is not power-of-2"
	http://lkml.indiana.edu/hypermail/linux/kernel/1205.2/03077.html

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:40 -07:00
Zhang Yanfei
9d1936cf86 mm/sparse: Remove unused ret in sparse_index_init
The ret variable is not used in the function, so remove it and
directly return 0 at the end of the function.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-28 12:02:13 +02:00
David Rientjes
4edd7ceff0 mm, hotplug: avoid compiling memory hotremove functions when disabled
__remove_pages() is only necessary for CONFIG_MEMORY_HOTREMOVE.  PowerPC
pseries will return -EOPNOTSUPP if unsupported.

Adding an #ifdef causes several other functions it depends on to also
become unnecessary, which saves in .text when disabled (it's disabled in
most defconfigs besides powerpc, including x86).  remove_memory_block()
becomes static since it is not referenced outside of
drivers/base/memory.c.

Build tested on x86 and powerpc with CONFIG_MEMORY_HOTREMOVE both enabled
and disabled.

Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:37 -07:00
Johannes Weiner
0aad818b2d sparse-vmemmap: specify vmemmap population range in bytes
The sparse code, when asking the architecture to populate the vmemmap,
specifies the section range as a starting page and a number of pages.

This is an awkward interface, because none of the arch-specific code
actually thinks of the range in terms of 'struct page' units and always
translates it to bytes first.

In addition, later patches mix huge page and regular page backing for
the vmemmap.  For this, they need to call vmemmap_populate_basepages()
on sub-section ranges with PAGE_SIZE and PMD_SIZE in mind.  But these
are not necessarily multiples of the 'struct page' size and so this unit
is too coarse.

Just translate the section range into bytes once in the generic sparse
code, then pass byte ranges down the stack.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Bernhard Schmidt <Bernhard.Schmidt@lrz.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: David S. Miller <davem@davemloft.net>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 15:54:35 -07:00
Xishi Qiu
293c07e31a memory-failure: use num_poisoned_pages instead of mce_bad_pages
Since MCE is an x86 concept, and this code is in mm/, it would be better
to use the name num_poisoned_pages instead of mce_bad_pages.

[akpm@linux-foundation.org: fix mm/sparse.c]
Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:15 -08:00
Wen Congyang
8a356ce38e memory-hotplug: consider compound pages when free memmap
usemap could also be allocated as compound pages.  Should also consider
compound pages when freeing memmap.

If we don't fix it, there could be problems when we free vmemmap
pagetables which are stored in compound pages.  The old pagetables will
not be freed properly, and when we add the memory again, no new
pagetable will be created.  And the old pagetable entry is used, than
the kernel will panic.

The call trace is like the following:

  BUG: unable to handle kernel paging request at ffffea0040000000
  IP: [<ffffffff816a483f>] sparse_add_one_section+0xef/0x166
  PGD 7ff7d4067 PUD 78e035067 PMD 78e11d067 PTE 0
  Oops: 0002 [#1] SMP
  Modules linked in: ip6table_filter ip6_tables ebtable_nat ebtables nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack ipt_REJECT xt_CHECKSUM iptable_mangle iptable_filter ip_tables bridge stp llc sunrpc binfmt_misc dm_mirror dm_region_hash dm_log dm_mod vhost_net macvtap macvlan tun uinput iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm crc32c_intel microcode pcspkr sg lpc_ich mfd_core i2c_i801 i2c_core i7core_edac edac_core ioatdma e1000e igb dca ptp pps_core sd_mod crc_t10dif megaraid_sas mptsas mptscsih mptbase scsi_transport_sas scsi_mod
  CPU 0
  Pid: 4, comm: kworker/0:0 Tainted: G        W 3.8.0-rc3-phy-hot-remove+ #3 FUJITSU-SV PRIMEQUEST 1800E/SB
  RIP: 0010:[<ffffffff816a483f>]  [<ffffffff816a483f>] sparse_add_one_section+0xef/0x166
  RSP: 0018:ffff8807bdcb35d8  EFLAGS: 00010006
  RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000200000
  RDX: ffff88078df01148 RSI: 0000000000000282 RDI: ffffea0040000000
  RBP: ffff8807bdcb3618 R08: 4cf05005b019467a R09: 0cd98fa09631467a
  R10: 0000000000000000 R11: 0000000000030e20 R12: 0000000000008000
  R13: ffffea0040000000 R14: ffff88078df66248 R15: ffff88078ea13b10
  FS:  0000000000000000(0000) GS:ffff8807c1a00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: ffffea0040000000 CR3: 0000000001c0c000 CR4: 00000000000007f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process kworker/0:0 (pid: 4, threadinfo ffff8807bdcb2000, task ffff8807bde18000)
  Call Trace:
    __add_pages+0x85/0x120
    arch_add_memory+0x71/0xf0
    add_memory+0xd6/0x1f0
    acpi_memory_device_add+0x170/0x20c
    acpi_device_probe+0x50/0x18a
    really_probe+0x6c/0x320
    driver_probe_device+0x47/0xa0
    __device_attach+0x53/0x60
    bus_for_each_drv+0x6c/0xa0
    device_attach+0xa8/0xc0
    bus_probe_device+0xb0/0xe0
    device_add+0x301/0x570
    device_register+0x1e/0x30
    acpi_device_register+0x1d8/0x27c
    acpi_add_single_object+0x1df/0x2b9
    acpi_bus_check_add+0x112/0x18f
    acpi_ns_walk_namespace+0x105/0x255
    acpi_walk_namespace+0xcf/0x118
    acpi_bus_scan+0x5b/0x7c
    acpi_bus_add+0x2a/0x2c
    container_notify_cb+0x112/0x1a9
    acpi_ev_notify_dispatch+0x46/0x61
    acpi_os_execute_deferred+0x27/0x34
    process_one_work+0x20e/0x5c0
    worker_thread+0x12e/0x370
    kthread+0xee/0x100
    ret_from_fork+0x7c/0xb0
  Code: 00 00 48 89 df 48 89 45 c8 e8 3e 71 b1 ff 48 89 c2 48 8b 75 c8 b8 ef ff ff ff f6 02 01 75 4b 49 63 cc 31 c0 4c 89 ef 48 c1 e1 06 <f3> aa 48 8b 02 48 83 c8 01 48 85 d2 48 89 02 74 29 a8 01 74 25
  RIP  [<ffffffff816a483f>] sparse_add_one_section+0xef/0x166
   RSP <ffff8807bdcb35d8>
  CR2: ffffea0040000000
  ---[ end trace e7f94e3a34c442d4 ]---
  Kernel panic - not syncing: Fatal exception

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:13 -08:00
Tang Chen
0197518cd3 memory-hotplug: remove memmap of sparse-vmemmap
Introduce a new API vmemmap_free() to free and remove vmemmap
pagetables.  Since pagetable implements are different, each architecture
has to provide its own version of vmemmap_free(), just like
vmemmap_populate().

Note: vmemmap_free() is not implemented for ia64, ppc, s390, and sparc.

[mhocko@suse.cz: fix implicit declaration of remove_pagetable]
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Wu Jianguo <wujianguo@huawei.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:12 -08:00
Tang Chen
cd099682e4 memory-hotplug: move pgdat_resize_lock into sparse_remove_one_section()
In __remove_section(), we locked pgdat_resize_lock when calling
sparse_remove_one_section().  This lock will disable irq.  But we don't
need to lock the whole function.  If we do some work to free pagetables
in free_section_usemap(), we need to call flush_tlb_all(), which need
irq enabled.  Otherwise the WARN_ON_ONCE() in smp_call_function_many()
will be triggered.

If we lock the whole sparse_remove_one_section(), then we come to this call trace:

  ------------[ cut here ]------------
  WARNING: at kernel/smp.c:461 smp_call_function_many+0xbd/0x260()
  Hardware name: PRIMEQUEST 1800E
  ......
  Call Trace:
    smp_call_function_many+0xbd/0x260
    smp_call_function+0x3b/0x50
    on_each_cpu+0x3b/0xc0
    flush_tlb_all+0x1c/0x20
    remove_pagetable+0x14e/0x1d0
    vmemmap_free+0x18/0x20
    sparse_remove_one_section+0xf7/0x100
    __remove_section+0xa2/0xb0
    __remove_pages+0xa0/0xd0
    arch_remove_memory+0x6b/0xc0
    remove_memory+0xb8/0xf0
    acpi_memory_device_remove+0x53/0x96
    acpi_device_remove+0x90/0xb2
    __device_release_driver+0x7c/0xf0
    device_release_driver+0x2f/0x50
    acpi_bus_remove+0x32/0x6d
    acpi_bus_trim+0x91/0x102
    acpi_bus_hot_remove_device+0x88/0x16b
    acpi_os_execute_deferred+0x27/0x34
    process_one_work+0x20e/0x5c0
    worker_thread+0x12e/0x370
    kthread+0xee/0x100
    ret_from_fork+0x7c/0xb0
  ---[ end trace 25e85300f542aa01 ]---

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Wu Jianguo <wujianguo@huawei.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-23 17:50:12 -08:00
Wen Congyang
3ac19f8efe memory-hotplug, mm/sparse.c: clear the memory to store struct page
If sparse memory vmemmap is enabled, we can't free the memory to store
struct page when a memory device is hotremoved, because we may store
struct page in the memory to manage the memory which doesn't belong to
this memory device.  When we hotadded this memory device again, we will
reuse this memory to store struct page, and struct page may contain some
obsolete information, and we will get bad-page state:

  init_memory_mapping: [mem 0x80000000-0x9fffffff]
  Built 2 zonelists in Node order, mobility grouping on.  Total pages: 547617
  Policy zone: Normal
  BUG: Bad page state in process bash  pfn:9b6dc
  page:ffffea0002200020 count:0 mapcount:0 mapping:          (null) index:0xfdfdfdfdfdfdfdfd
  page flags: 0x2fdfdfdfd5df9fd(locked|referenced|uptodate|dirty|lru|active|slab|owner_priv_1|private|private_2|writeback|head|tail|swapcache|reclaim|swapbacked|unevictable|uncached|compound_lock)
  Modules linked in: netconsole acpiphp pci_hotplug acpi_memhotplug loop kvm_amd kvm microcode tpm_tis tpm tpm_bios evdev psmouse serio_raw i2c_piix4 i2c_core parport_pc parport processor button thermal_sys ext3 jbd mbcache sg sr_mod cdrom ata_generic virtio_net ata_piix virtio_blk libata virtio_pci virtio_ring virtio scsi_mod
  Pid: 988, comm: bash Not tainted 3.6.0-rc7-guest #12
  Call Trace:
   [<ffffffff810e9b30>] ? bad_page+0xb0/0x100
   [<ffffffff810ea4c3>] ? free_pages_prepare+0xb3/0x100
   [<ffffffff810ea668>] ? free_hot_cold_page+0x48/0x1a0
   [<ffffffff8112cc08>] ? online_pages_range+0x68/0xa0
   [<ffffffff8112cba0>] ? __online_page_increment_counters+0x10/0x10
   [<ffffffff81045561>] ? walk_system_ram_range+0x101/0x110
   [<ffffffff814c4f95>] ? online_pages+0x1a5/0x2b0
   [<ffffffff8135663d>] ? __memory_block_change_state+0x20d/0x270
   [<ffffffff81356756>] ? store_mem_state+0xb6/0xf0
   [<ffffffff8119e482>] ? sysfs_write_file+0xd2/0x160
   [<ffffffff8113769a>] ? vfs_write+0xaa/0x160
   [<ffffffff81137977>] ? sys_write+0x47/0x90
   [<ffffffff814e2f25>] ? async_page_fault+0x25/0x30
   [<ffffffff814ea239>] ? system_call_fastpath+0x16/0x1b
  Disabling lock debugging due to kernel taint

This patch clears the memory to store struct page to avoid unexpected error.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reported-by: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11 17:22:23 -08:00
Wen Congyang
95a4774d05 memory-hotplug: update mce_bad_pages when removing the memory
When we hotremove a memory device, we will free the memory to store struct
page.  If the page is hwpoisoned page, we should decrease mce_bad_pages.

[akpm@linux-foundation.org: cleanup ifdefs]
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-11 17:22:22 -08:00
Jianguo Wu
ae64ffcac3 mm/vmemmap: fix wrong use of virt_to_page
I enable CONFIG_DEBUG_VIRTUAL and CONFIG_SPARSEMEM_VMEMMAP, when doing
memory hotremove, there is a kernel BUG at arch/x86/mm/physaddr.c:20.

It is caused by free_section_usemap()->virt_to_page(), virt_to_page() is
only used for kernel direct mapping address, but sparse-vmemmap uses
vmemmap address, so it is going wrong here.

  ------------[ cut here ]------------
  kernel BUG at arch/x86/mm/physaddr.c:20!
  invalid opcode: 0000 [#1] SMP
  Modules linked in: acpihp_drv acpihp_slot edd cpufreq_conservative cpufreq_userspace cpufreq_powersave acpi_cpufreq mperf fuse vfat fat loop dm_mod coretemp kvm crc32c_intel ipv6 ixgbe igb iTCO_wdt i7core_edac edac_core pcspkr iTCO_vendor_support ioatdma microcode joydev sr_mod i2c_i801 dca lpc_ich mfd_core mdio tpm_tis i2c_core hid_generic tpm cdrom sg tpm_bios rtc_cmos button ext3 jbd mbcache usbhid hid uhci_hcd ehci_hcd usbcore usb_common sd_mod crc_t10dif processor thermal_sys hwmon scsi_dh_alua scsi_dh_hp_sw scsi_dh_rdac scsi_dh_emc scsi_dh ata_generic ata_piix libata megaraid_sas scsi_mod
  CPU 39
  Pid: 6454, comm: sh Not tainted 3.7.0-rc1-acpihp-final+ #45 QCI QSSC-S4R/QSSC-S4R
  RIP: 0010:[<ffffffff8103c908>]  [<ffffffff8103c908>] __phys_addr+0x88/0x90
  RSP: 0018:ffff8804440d7c08  EFLAGS: 00010006
  RAX: 0000000000000006 RBX: ffffea0012000000 RCX: 000000000000002c
  ...

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Reviewd-by: Wen Congyang <wency@cn.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-30 08:51:17 -08:00
Gavin Shan
c1c9518331 mm/sparse: remove index_init_lock
sparse_index_init() uses the index_init_lock spinlock to protect root
mem_section assignment.  The lock is not necessary anymore because the
function is called only during boot (during paging init which is executed
only from a single CPU) and from the hotplug code (by add_memory() via
arch_add_memory()) which uses mem_hotplug_mutex.

The lock was introduced by 28ae55c9 ("sparsemem extreme: hotplug
preparation") and sparse_index_init() was used only during boot at that
time.

Later when the hotplug code (and add_memory()) was introduced there was no
synchronization so it was possible to online more sections from the same
root probably (though I am not 100% sure about that).  The first
synchronization has been added by 6ad696d2 ("mm: allow memory hotplug and
hibernation in the same kernel") which was later replaced by the
mem_hotplug_mutex - 20d6c96b ("mem-hotplug: introduce
{un}lock_memory_hotplug()").

Let's remove the lock as it is not needed and it makes the code more
confusing.

[mhocko@suse.cz: changelog]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:49 -07:00
Gavin Shan
db36a46113 mm/sparse: more checks on mem_section number
__section_nr() was implemented to retrieve the corresponding memory
section number according to its descriptor.  It's possible that the
specified memory section descriptor doesn't exist in the global array.  So
add more checking on that and report an error for a wrong case.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:49 -07:00
Gavin Shan
5b760e64a6 mm/sparse: optimize sparse_index_alloc
With CONFIG_SPARSEMEM_EXTREME, the two levels of memory section
descriptors are allocated from slab or bootmem.  When allocating from
slab, let slab/bootmem allocator clear the memory chunk.  We needn't clear
it explicitly.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:49 -07:00
Xishi Qiu
ca57df79d4 mm: setup pageblock_order before it's used by sparsemem
On architectures with CONFIG_HUGETLB_PAGE_SIZE_VARIABLE set, such as
Itanium, pageblock_order is a variable with default value of 0.  It's set
to the right value by set_pageblock_order() in function
free_area_init_core().

But pageblock_order may be used by sparse_init() before free_area_init_core()
is called along path:
sparse_init()
    ->sparse_early_usemaps_alloc_node()
	->usemap_size()
	    ->SECTION_BLOCKFLAGS_BITS
		->((1UL << (PFN_SECTION_SHIFT - pageblock_order)) *
NR_PAGEBLOCK_BITS)

The uninitialized pageblock_size will cause memory wasting because
usemap_size() returns a much bigger value then it's really needed.

For example, on an Itanium platform,
sparse_init() pageblock_order=0 usemap_size=24576
free_area_init_core() before pageblock_order=0, usemap_size=24576
free_area_init_core() after pageblock_order=12, usemap_size=8

That means 24K memory has been wasted for each section, so fix it by calling
set_pageblock_order() from sparse_init().

Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Keping Chen <chenkeping@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:43 -07:00
Yinghai Lu
99ab7b1944 mm: sparse: fix usemap allocation above node descriptor section
After commit f5bf18fa22 ("bootmem/sparsemem: remove limit constraint
in alloc_bootmem_section"), usemap allocations may easily be placed
outside the optimal section that holds the node descriptor, even if
there is space available in that section.  This results in unnecessary
hotplug dependencies that need to have the node unplugged before the
section holding the usemap.

The reason is that the bootmem allocator doesn't guarantee a linear
search starting from the passed allocation goal but may start out at a
much higher address absent an upper limit.

Fix this by trying the allocation with the limit at the section end,
then retry without if that fails.  This keeps the fix from f5bf18fa22
of not panicking if the allocation does not fit in the section, but
still makes sure to try to stay within the section at first.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>	[3.3.x, 3.4.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-11 16:04:49 -07:00
Yinghai Lu
07b4e2bc9c mm: sparse: fix section usemap placement calculation
Commit 238305bb4d ("mm: remove sparsemem allocation details from the
bootmem allocator") introduced a bug in the allocation goal calculation
that put section usemaps not in the same section as the node
descriptors, creating unnecessary hotplug dependencies between them:

  node 0 must be removed before remove section 16399
  node 1 must be removed before remove section 16399
  node 2 must be removed before remove section 16399
  node 3 must be removed before remove section 16399
  node 4 must be removed before remove section 16399
  node 5 must be removed before remove section 16399
  node 6 must be removed before remove section 16399

The reason is that it applies PAGE_SECTION_MASK to the physical address
of the node descriptor when finding a suitable place to put the usemap,
when this mask is actually intended to be used with PFNs.  Because the
PFN mask is wider, the target address will point beyond the wanted
section holding the node descriptor and the node must be offlined before
the section holding the usemap can go.

Fix this by extending the mask to address width before use.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-11 16:04:49 -07:00
Johannes Weiner
238305bb4d mm: remove sparsemem allocation details from the bootmem allocator
alloc_bootmem_section() derives allocation area constraints from the
specified sparsemem section.  This is a bit specific for a generic memory
allocator like bootmem, though, so move it over to sparsemem.

As __alloc_bootmem_node_nopanic() already retries failed allocations with
relaxed area constraints, the fallback code in sparsemem.c can be removed
and the code becomes a bit more compact overall.

[akpm@linux-foundation.org: fix build]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-29 16:22:22 -07:00
Nishanth Aravamudan
f5bf18fa22 bootmem/sparsemem: remove limit constraint in alloc_bootmem_section
While testing AMS (Active Memory Sharing) / CMO (Cooperative Memory
Overcommit) on powerpc, we tripped the following:

  kernel BUG at mm/bootmem.c:483!
  cpu 0x0: Vector: 700 (Program Check) at [c000000000c03940]
      pc: c000000000a62bd8: .alloc_bootmem_core+0x90/0x39c
      lr: c000000000a64bcc: .sparse_early_usemaps_alloc_node+0x84/0x29c
      sp: c000000000c03bc0
     msr: 8000000000021032
    current = 0xc000000000b0cce0
    paca    = 0xc000000001d80000
      pid   = 0, comm = swapper
  kernel BUG at mm/bootmem.c:483!
  enter ? for help
  [c000000000c03c80] c000000000a64bcc
  .sparse_early_usemaps_alloc_node+0x84/0x29c
  [c000000000c03d50] c000000000a64f10 .sparse_init+0x12c/0x28c
  [c000000000c03e20] c000000000a474f4 .setup_arch+0x20c/0x294
  [c000000000c03ee0] c000000000a4079c .start_kernel+0xb4/0x460
  [c000000000c03f90] c000000000009670 .start_here_common+0x1c/0x2c

This is

        BUG_ON(limit && goal + size > limit);

and after some debugging, it seems that

	goal = 0x7ffff000000
	limit = 0x80000000000

and sparse_early_usemaps_alloc_node ->
sparse_early_usemaps_alloc_pgdat_section calls

	return alloc_bootmem_section(usemap_size() * count, section_nr);

This is on a system with 8TB available via the AMS pool, and as a quirk
of AMS in firmware, all of that memory shows up in node 0.  So, we end
up with an allocation that will fail the goal/limit constraints.

In theory, we could "fall-back" to alloc_bootmem_node() in
sparse_early_usemaps_alloc_node(), but since we actually have HOTREMOVE
defined, we'll BUG_ON() instead.  A simple solution appears to be to
unconditionally remove the limit condition in alloc_bootmem_section,
meaning allocations are allowed to cross section boundaries (necessary
for systems of this size).

Johannes Weiner pointed out that if alloc_bootmem_section() no longer
guarantees section-locality, we need check_usemap_section_nr() to print
possible cross-dependencies between node descriptors and the usemaps
allocated through it.  That makes the two loops in
sparse_early_usemaps_alloc_node() identical, so re-factor the code a
bit.

[akpm@linux-foundation.org: code simplification]
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Anton Blanchard <anton@au1.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ben Herrenschmidt <benh@kernel.crashing.org>
Cc: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org>	[3.3.1]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21 17:54:58 -07:00
Paul Gortmaker
b95f1b31b7 mm: Map most files to use export.h instead of module.h
The files changed within are only using the EXPORT_SYMBOL
macro variants.  They are not using core modular infrastructure
and hence don't need module.h but only the export.h header.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 09:20:12 -04:00
Ian Campbell
33dd4e0ec9 mm: make some struct page's const
These uses are read-only and in a subsequent patch I have a const struct
page in my hand...

[akpm@linux-foundation.org: fix warnings in lowmem_page_address()]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:07 -07:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Andrea Arcangeli
5f24ce5fd3 thp: remove PG_buddy
PG_buddy can be converted to _mapcount == -2.  So the PG_compound_lock can
be added to page->flags without overflowing (because of the sparse section
bits increasing) with CONFIG_X86_PAE=y and CONFIG_X86_PAT=y.  This also
has to move the memory hotplug code from _mapcount to lru.next to avoid
any risk of clashes.  We can't use lru.next for PG_buddy removal, but
memory hotplug can use lru.next even more easily than the mapcount
instead.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:43 -08:00
Yinghai Lu
e48e67e08c sparsemem: on no vmemmap path put mem_map on node high too
We need to put mem_map high when virtual memmap is not used.

before this patch
free mem pfn range on first node:
[    0.000000]  19 - 1f
[    0.000000]  28 40 - 80 95
[    0.000000]  702 740 - 1000 1000
[    0.000000]  347c - 347e
[    0.000000]  34e7 3500 - 3b80 3b8b
[    0.000000]  73b8b 73bc0 - 73c00 73c00
[    0.000000]  73ddd - 73e00
[    0.000000]  73fdd - 74000
[    0.000000]  741dd - 74200
[    0.000000]  743dd - 74400
[    0.000000]  745dd - 74600
[    0.000000]  747dd - 74800
[    0.000000]  749dd - 74a00
[    0.000000]  74bdd - 74c00
[    0.000000]  74ddd - 74e00
[    0.000000]  74fdd - 75000
[    0.000000]  751dd - 75200
[    0.000000]  753dd - 75400
[    0.000000]  755dd - 75600
[    0.000000]  757dd - 75800
[    0.000000]  759dd - 75a00
[    0.000000]  79bdd 79c00 - 7d540 7d550
[    0.000000]  7f745 - 7f750
[    0.000000]  10000b 100040 - 2080000 2080000
so only 79c00 - 7d540 are major free block under 4g...

after this patch, we will get
[    0.000000]  19 - 1f
[    0.000000]  28 40 - 80 95
[    0.000000]  702 740 - 1000 1000
[    0.000000]  347c - 347e
[    0.000000]  34e7 3500 - 3600 3600
[    0.000000]  37dd - 3800
[    0.000000]  39dd - 3a00
[    0.000000]  3bdd - 3c00
[    0.000000]  3ddd - 3e00
[    0.000000]  3fdd - 4000
[    0.000000]  41dd - 4200
[    0.000000]  43dd - 4400
[    0.000000]  45dd - 4600
[    0.000000]  47dd - 4800
[    0.000000]  49dd - 4a00
[    0.000000]  4bdd - 4c00
[    0.000000]  4ddd - 4e00
[    0.000000]  4fdd - 5000
[    0.000000]  51dd - 5200
[    0.000000]  53dd - 5400
[    0.000000]  95dd 9600 - 7d540 7d550
[    0.000000]  7f745 - 7f750
[    0.000000]  17000b 170040 - 2080000 2080000
we will have 9600 - 7d540 for major free block...

sparse-vmemmap path already used __alloc_bootmem_node_high()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:06:56 -07:00
Tejun Heo
5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Yinghai Lu
81d0d950e5 sparsemem: Fix compilation on PowerPC
Stephen reported:
build (powerpc
ppc64_defconfig) produced these warnings:

mm/sparse.c: In function 'sparse_init':
mm/sparse.c:488: warning: unused variable 'map_count'
mm/sparse.c:484: warning: unused variable 'size2'
mm/sparse.c:481: warning: unused variable 'map_map'
mm/sparse.c: At top level:
mm/sparse.c:442: warning: 'sparse_early_mem_maps_alloc_node' defined but not used

Introduced by commit 9bdac91424
("sparsemem: Put mem map for one node together").

Conditionalize the bits appropriately based on the setting of
CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B895682.1080706@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-03-01 17:59:24 -08:00
Yinghai Lu
9bdac91424 sparsemem: Put mem map for one node together.
Add vmemmap_alloc_block_buf for mem map only.

It will fallback to the old way if it cannot get a block that big.

Before this patch, when a node have 128g ram installed, memmap are
split into two parts or more.
[    0.000000]  [ffffea0000000000-ffffea003fffffff] PMD -> [ffff880100600000-ffff88013e9fffff] on node 1
[    0.000000]  [ffffea0040000000-ffffea006fffffff] PMD -> [ffff88013ec00000-ffff88016ebfffff] on node 1
[    0.000000]  [ffffea0070000000-ffffea007fffffff] PMD -> [ffff882000600000-ffff8820105fffff] on node 0
[    0.000000]  [ffffea0080000000-ffffea00bfffffff] PMD -> [ffff882010800000-ffff8820507fffff] on node 0
[    0.000000]  [ffffea00c0000000-ffffea00dfffffff] PMD -> [ffff882050a00000-ffff8820709fffff] on node 0
[    0.000000]  [ffffea00e0000000-ffffea00ffffffff] PMD -> [ffff884000600000-ffff8840205fffff] on node 2
[    0.000000]  [ffffea0100000000-ffffea013fffffff] PMD -> [ffff884020800000-ffff8840607fffff] on node 2
[    0.000000]  [ffffea0140000000-ffffea014fffffff] PMD -> [ffff884060a00000-ffff8840709fffff] on node 2
[    0.000000]  [ffffea0150000000-ffffea017fffffff] PMD -> [ffff886000600000-ffff8860305fffff] on node 3
[    0.000000]  [ffffea0180000000-ffffea01bfffffff] PMD -> [ffff886030800000-ffff8860707fffff] on node 3
[    0.000000]  [ffffea01c0000000-ffffea01ffffffff] PMD -> [ffff888000600000-ffff8880405fffff] on node 4
[    0.000000]  [ffffea0200000000-ffffea022fffffff] PMD -> [ffff888040800000-ffff8880707fffff] on node 4
[    0.000000]  [ffffea0230000000-ffffea023fffffff] PMD -> [ffff88a000600000-ffff88a0105fffff] on node 5
[    0.000000]  [ffffea0240000000-ffffea027fffffff] PMD -> [ffff88a010800000-ffff88a0507fffff] on node 5
[    0.000000]  [ffffea0280000000-ffffea029fffffff] PMD -> [ffff88a050a00000-ffff88a0709fffff] on node 5
[    0.000000]  [ffffea02a0000000-ffffea02bfffffff] PMD -> [ffff88c000600000-ffff88c0205fffff] on node 6
[    0.000000]  [ffffea02c0000000-ffffea02ffffffff] PMD -> [ffff88c020800000-ffff88c0607fffff] on node 6
[    0.000000]  [ffffea0300000000-ffffea030fffffff] PMD -> [ffff88c060a00000-ffff88c0709fffff] on node 6
[    0.000000]  [ffffea0310000000-ffffea033fffffff] PMD -> [ffff88e000600000-ffff88e0305fffff] on node 7
[    0.000000]  [ffffea0340000000-ffffea037fffffff] PMD -> [ffff88e030800000-ffff88e0707fffff] on node 7

after patch will get
[    0.000000]  [ffffea0000000000-ffffea006fffffff] PMD -> [ffff880100200000-ffff88016e5fffff] on node 0
[    0.000000]  [ffffea0070000000-ffffea00dfffffff] PMD -> [ffff882000200000-ffff8820701fffff] on node 1
[    0.000000]  [ffffea00e0000000-ffffea014fffffff] PMD -> [ffff884000200000-ffff8840701fffff] on node 2
[    0.000000]  [ffffea0150000000-ffffea01bfffffff] PMD -> [ffff886000200000-ffff8860701fffff] on node 3
[    0.000000]  [ffffea01c0000000-ffffea022fffffff] PMD -> [ffff888000200000-ffff8880701fffff] on node 4
[    0.000000]  [ffffea0230000000-ffffea029fffffff] PMD -> [ffff88a000200000-ffff88a0701fffff] on node 5
[    0.000000]  [ffffea02a0000000-ffffea030fffffff] PMD -> [ffff88c000200000-ffff88c0701fffff] on node 6
[    0.000000]  [ffffea0310000000-ffffea037fffffff] PMD -> [ffff88e000200000-ffff88e0701fffff] on node 7

-v2: change buf to vmemmap_buf instead according to Ingo
     also add CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER according to Ingo
-v3: according to Andrew, use sizeof(name) instead of hard coded 15

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-19-git-send-email-yinghai@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-12 09:42:38 -08:00
Yinghai Lu
a4322e1bad sparsemem: Put usemap for one node together
Could save some buffer space instead of applying one by one.

Could help that system that is going to use early_res instead of bootmem
less entries in early_res make search more faster on system with more memory.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-18-git-send-email-yinghai@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-12 09:42:37 -08:00
Shaohua Li
f52407ce2d memory hotplug: alloc page from other node in memory online
To initialize hotadded node, some pages are allocated.  At that time, the
node hasn't memory, this makes the allocation always fail.  In such case,
let's allocate pages from other nodes.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Yakui Zhao <yakui.zhao@intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:26 -07:00
Cyrill Gorcunov
ef161a9863 mm: mminit_validate_memmodel_limits(): remove redundant test
In case if start_pfn overlap the upper bound no need to test end_pfn again
since we have it already trimmed.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:11 -07:00
Al Viro
31168481c3 meminit section warnings
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-30 10:03:35 -08:00
Huang Weiyi
fc1efbdb7a mm/sparse.c: removed duplicated include
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:30 -07:00
Adrian Bunk
9e5c6da71e make mm/sparse.c: make a function static
This patch makes the needlessly global sparse_early_mem_map_alloc()
static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:12 -07:00
Yasunori Goto
48c906823f memory hotplug: allocate usemap on the section with pgdat
Usemaps are allocated on the section which has pgdat by this.

Because usemap size is very small, many other sections usemaps are
allocated on only one page.  If a section has usemap, it can't be removed
until removing other sections.  This dependency is not desirable for
memory removing.

Pgdat has similar feature.  When a section has pgdat area, it must be the
last section for removing on the node.  So, if section A has pgdat and
section B has usemap for section A, Both sections can't be removed due to
dependency each other.

To solve this issue, this patch collects usemap on same section with pgdat
as much as possible.  If other sections doesn't have any dependency, this
section will be able to be removed finally.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: David Miller <davem@davemloft.net>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hiroyuki KAMEZAWA <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:21 -07:00
Mel Gorman
2dbb51c49f mm: make defensive checks around PFN values registered for memory usage
There are a number of different views to how much memory is currently active.
There is the arch-independent zone-sizing view, the bootmem allocator and
memory models view.

Architectures register this information at different times and is not
necessarily in sync particularly with respect to some SPARSEMEM limitations.

This patch introduces mminit_validate_memmodel_limits() which is able to
validate and correct PFN ranges with respect to the memory model.  It is only
SPARSEMEM that currently validates itself.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:13 -07:00
Andrew Morton
5167464446 revert "memory hotplug: allocate usemap on the section with pgdat"
This:

commit 86f6dae137
Author: Yasunori Goto <y-goto@jp.fujitsu.com>
Date:   Mon Apr 28 02:13:33 2008 -0700

    memory hotplug: allocate usemap on the section with pgdat

    Usemaps are allocated on the section which has pgdat by this.

    Because usemap size is very small, many other sections usemaps are allocated
    on only one page.  If a section has usemap, it can't be removed until removing
    other sections.  This dependency is not desirable for memory removing.

    Pgdat has similar feature.  When a section has pgdat area, it must be the last
    section for removing on the node.  So, if section A has pgdat and section B
    has usemap for section A, Both sections can't be removed due to dependency
    each other.

    To solve this issue, this patch collects usemap on same section with pgdat.
    If other sections doesn't have any dependency, this section will be able to be
    removed finally.

    Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
    Cc: Badari Pulavarty <pbadari@us.ibm.com>
    Cc: Yinghai Lu <yhlu.kernel@gmail.com>
    Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

broke davem's sparc64 bootup.  Revert it while we work out what went wrong.

Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:55 -07:00
Harvey Harrison
d40cee245f mm: remove remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Yasunori Goto
0c0a4a517a memory hotplug: free memmaps allocated by bootmem
This patch is to free memmaps which is allocated by bootmem.

Freeing usemap is not necessary.  The pages of usemap may be necessary for
other sections.

If removing section is last section on the node, its section is the final user
of usemap page.  (usemaps are allocated on its section by previous patch.) But
it shouldn't be freed too, because the section must be logical offline state
which all pages are isolated against page allocater.  If it is freed, page
alloctor may use it which will be removed physically soon.  It will be
disaster.  So, this patch keeps it as it is.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:26 -07:00
Yasunori Goto
86f6dae137 memory hotplug: allocate usemap on the section with pgdat
Usemaps are allocated on the section which has pgdat by this.

Because usemap size is very small, many other sections usemaps are allocated
on only one page.  If a section has usemap, it can't be removed until removing
other sections.  This dependency is not desirable for memory removing.

Pgdat has similar feature.  When a section has pgdat area, it must be the last
section for removing on the node.  So, if section A has pgdat and section B
has usemap for section A, Both sections can't be removed due to dependency
each other.

To solve this issue, this patch collects usemap on same section with pgdat.
If other sections doesn't have any dependency, this section will be able to be
removed finally.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:25 -07:00
Yasunori Goto
9d99217a02 memory hotplug: align memmap to page size
To free memmap easier, this patch aligns it to page size.  Bootmem allocater
may mix some objects in one pages.  It's not good for freeing memmap of memory
hot-remove.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:25 -07:00
Yasunori Goto
0475327876 memory hotplug: register section/node id to free
This patch set is to free pages which is allocated by bootmem for
memory-hotremove.  Some structures of memory management are allocated by
bootmem.  ex) memmap, etc.

To remove memory physically, some of them must be freed according to
circumstance.  This patch set makes basis to free those pages, and free
memmaps.

Basic my idea is using remain members of struct page to remember information
of users of bootmem (section number or node id).  When the section is
removing, kernel can confirm it.  By this information, some issues can be
solved.

  1) When the memmap of removing section is allocated on other
     section by bootmem, it should/can be free.
  2) When the memmap of removing section is allocated on the
     same section, it shouldn't be freed. Because the section has to be
     logical memory offlined already and all pages must be isolated against
     page allocater. If it is freed, page allocator may use it which will
     be removed physically soon.
  3) When removing section has other section's memmap,
     kernel will be able to show easily which section should be removed
     before it for user. (Not implemented yet)
  4) When the above case 2), the page isolation will be able to check and skip
     memmap's page when logical memory offline (offline_pages()).
     Current page isolation code fails in this case because this page is
     just reserved page and it can't distinguish this pages can be
     removed or not. But, it will be able to do by this patch.
     (Not implemented yet.)
  5) The node information like pgdat has similar issues. But, this
     will be able to be solved too by this.
     (Not implemented yet, but, remembering node id in the pages.)

Fortunately, current bootmem allocator just keeps PageReserved flags,
and doesn't use any other members of page struct. The users of
bootmem doesn't use them too.

This patch:

This is to register information which is node or section's id.  Kernel can
distinguish which node/section uses the pages allcated by bootmem.  This is
basis for hot-remove sections or nodes.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:25 -07:00
Badari Pulavarty
ea01ea937d hotplug memory remove: generic __remove_pages() support
Generic helper function to remove section mappings and sysfs entries for the
section of the memory we are removing.  offline_pages() correctly adjusted
zone and marked the pages reserved.

TODO: Yasunori Goto is working on patches to free up allocations from bootmem.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:17 -07:00
Yinghai Lu
c2b91e2eec x86_64/mm: check and print vmemmap allocation continuous
On big systems with lots of memory, don't print out too much during
bootup, and make it easy to find if it is continuous.

on 256G 8 sockets system will get
 [ffffe20000000000-ffffe20002bfffff] PMD -> [ffff810001400000-ffff810003ffffff] on node 0
[ffffe2001c700000-ffffe2001c7fffff] potential offnode page_structs
 [ffffe20002c00000-ffffe2001c7fffff] PMD -> [ffff81000c000000-ffff8100255fffff] on node 0
[ffffe20038700000-ffffe200387fffff] potential offnode page_structs
 [ffffe2001c800000-ffffe200387fffff] PMD -> [ffff810820200000-ffff81083c1fffff] on node 1
 [ffffe20040000000-ffffe2007fffffff] PUD ->ffff811027a00000 on node 2
 [ffffe20038800000-ffffe2003fffffff] PMD -> [ffff811020200000-ffff8110279fffff] on node 2
[ffffe20054700000-ffffe200547fffff] potential offnode page_structs
 [ffffe20040000000-ffffe200547fffff] PMD -> [ffff811027c00000-ffff81103c3fffff] on node 2
[ffffe20070700000-ffffe200707fffff] potential offnode page_structs
 [ffffe20054800000-ffffe200707fffff] PMD -> [ffff811820200000-ffff81183c1fffff] on node 3
 [ffffe20080000000-ffffe200bfffffff] PUD ->ffff81202fa00000 on node 4
 [ffffe20070800000-ffffe2007fffffff] PMD -> [ffff812020200000-ffff81202f9fffff] on node 4
[ffffe2008c700000-ffffe2008c7fffff] potential offnode page_structs
 [ffffe20080000000-ffffe2008c7fffff] PMD -> [ffff81202fc00000-ffff81203c3fffff] on node 4
[ffffe200a8700000-ffffe200a87fffff] potential offnode page_structs
 [ffffe2008c800000-ffffe200a87fffff] PMD -> [ffff812820200000-ffff81283c1fffff] on node 5
 [ffffe200c0000000-ffffe200ffffffff] PUD ->ffff813037a00000 on node 6
 [ffffe200a8800000-ffffe200bfffffff] PMD -> [ffff813020200000-ffff8130379fffff] on node 6
[ffffe200c4700000-ffffe200c47fffff] potential offnode page_structs
 [ffffe200c0000000-ffffe200c47fffff] PMD -> [ffff813037c00000-ffff81303c3fffff] on node 6
 [ffffe200c4800000-ffffe200e07fffff] PMD -> [ffff813820200000-ffff81383c1fffff] on node 7

instead of a very long print out...

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-26 22:51:09 +02:00
Yinghai Lu
e123dd3f0e mm: make mem_map allocation continuous
vmemmap allocation currently has this layout:

 [ffffe20000000000-ffffe200001fffff] PMD ->ffff810001400000 on node 0
 [ffffe20000200000-ffffe200003fffff] PMD ->ffff810001800000 on node 0
 [ffffe20000400000-ffffe200005fffff] PMD ->ffff810001c00000 on node 0
 [ffffe20000600000-ffffe200007fffff] PMD ->ffff810002000000 on node 0
 [ffffe20000800000-ffffe200009fffff] PMD ->ffff810002400000 on node 0
...

note that there is a 2M hole between them - not optimal.

the root cause is that usemap (24 bytes) will be allocated after every 2M
mem_map, and it will push next vmemmap (2M) to the next (2M) alignment.

solution: try to allocate the mem_map continously.

after the patch, we get:

 [ffffe20000000000-ffffe200001fffff] PMD ->ffff810001400000 on node 0
 [ffffe20000200000-ffffe200003fffff] PMD ->ffff810001600000 on node 0
 [ffffe20000400000-ffffe200005fffff] PMD ->ffff810001800000 on node 0
 [ffffe20000600000-ffffe200007fffff] PMD ->ffff810001a00000 on node 0
 [ffffe20000800000-ffffe200009fffff] PMD ->ffff810001c00000 on node 0
...

which is the ideal layout.

and usemap will share a page because of they are allocated continuously too:

sparse_early_usemap_alloc: usemap = ffff810024e00000 size = 24
sparse_early_usemap_alloc: usemap = ffff810024e00080 size = 24
sparse_early_usemap_alloc: usemap = ffff810024e00100 size = 24
sparse_early_usemap_alloc: usemap = ffff810024e00180 size = 24
...

so we make the bootmem allocation more compact and use less memory
for usemap => mission accomplished ;-)

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 22:51:07 +02:00
Ingo Molnar
bead9a3abd mm: sparsemem memory_present() fix
Fix memory corruption and crash on 32-bit x86 systems.

If a !PAE x86 kernel is booted on a 32-bit system with more than 4GB of
RAM, then we call memory_present() with a start/end that goes outside
the scope of MAX_PHYSMEM_BITS.

That causes this loop to happily walk over the limit of the sparse
memory section map:

    for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
                unsigned long section = pfn_to_section_nr(pfn);
                struct mem_section *ms;

                sparse_index_init(section, nid);
                set_section_nid(section, nid);

                ms = __nr_to_section(section);
                if (!ms->section_mem_map)
                        ms->section_mem_map = sparse_encode_early_nid(nid) |
			                                SECTION_MARKED_PRESENT;

'ms' will be out of bounds and we'll corrupt a small amount of memory by
encoding the node ID and writing SECTION_MARKED_PRESENT (==0x1) over it.

The corruption might happen when encoding a non-zero node ID, or due to
the SECTION_MARKED_PRESENT which is 0x1:

	mmzone.h:#define	SECTION_MARKED_PRESENT	(1UL<<0)

The fix is to sanity check anything the architecture passes to
sparsemem.

This bug seems to be rather old (as old as sparsemem support itself),
but the exact incarnation depended on random details like configs, which
made this bug more prominent in v2.6.25-to-be.

An additional enhancement might be to print a warning about ignored or
trimmed memory ranges.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <Yinghai.Lu@sun.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-15 19:30:19 -07:00
Sam Ravnborg
a322f8ab66 mm: fix section mismatch warning in sparse.c
Fix following warning:
WARNING: mm/built-in.o(.text+0x22069): Section mismatch in reference from the function sparse_early_usemap_alloc() to the function .init.text:__alloc_bootmem_node()

static sparse_early_usemap_alloc() were used only by sparse_init()
and with sparse_init() annotated _init it is safe to
annotate sparse_early_usemap_alloc with __init too.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:19 -08:00
Christoph Lameter
9e2779fa28 is_vmalloc_addr(): Check if an address is within the vmalloc boundaries
Checking if an address is a vmalloc address is done in a couple of places.
Define a common version in mm.h and replace the other checks.

Again the include structures suck.  The definition of VMALLOC_START and
VMALLOC_END is not available in vmalloc.h since highmem.c cannot be included
there.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05 09:44:14 -08:00
WANG Cong
bbd0682596 mm/sparse.c: improve the error handling for sparse_add_one_section()
Improve the error handling for mm/sparse.c::sparse_add_one_section().  And I
see no reason to check 'usemap' until holding the 'pgdat_resize_lock'.

[geoffrey.levand@am.sony.com: sparse_index_init() returns -EEXIST]
Cc: Christoph Lameter <clameter@sgi.com>
Acked-by: Dave Hansen <haveblue@us.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:16 -08:00
WANG Cong
af0cd5a7c3 mm/sparse.c: check the return value of sparse_index_alloc()
Since sparse_index_alloc() can return NULL on memory allocation failure,
we must deal with the failure condition when calling it.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-17 19:28:16 -08:00
Linus Torvalds
6a22c57b8d Revert "x86_64: allocate sparsemem memmap above 4G"
This reverts commit 2e1c49db4c.

First off, testing in Fedora has shown it to cause boot failures,
bisected down by Martin Ebourne, and reported by Dave Jobes.  So the
commit will likely be reverted in the 2.6.23 stable kernels.

Secondly, in the 2.6.24 model, x86-64 has now grown support for
SPARSEMEM_VMEMMAP, which disables the relevant code anyway, so while the
bug is not visible any more, it's become invisible due to the code just
being irrelevant and no longer enabled on the only architecture that
this ever affected.

Reported-by: Dave Jones <davej@redhat.com>
Tested-by: Martin Ebourne <fedora@ebourne.me.uk>
Cc: Zou Nan hai <nanhai.zou@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-29 14:05:37 -07:00
Yasunori Goto
98f3cfc1dc memory hotplug: Hot-add with sparsemem-vmemmap
This patch is to avoid panic when memory hot-add is executed with
sparsemem-vmemmap.  Current vmemmap-sparsemem code doesn't support memory
hot-add.  Vmemmap must be populated when hot-add.  This is for
2.6.23-rc2-mm2.

Todo: # Even if this patch is applied, the message "[xxxx-xxxx] potential
        offnode page_structs" is displayed. To allocate memmap on its node,
        memmap (and pgdat) must be initialized itself like chicken and
        egg relationship.

      # vmemmap_unpopulate will be necessary for followings.
         - For cancel hot-add due to error.
         - For unplug.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:02 -07:00
Mel Gorman
5c0e306647 Fix corruption of memmap on IA64 SPARSEMEM when mem_section is not a power of 2
There are problems in the use of SPARSEMEM and pageblock flags that causes
problems on ia64.

The first part of the problem is that units are incorrect in
SECTION_BLOCKFLAGS_BITS computation.  This results in a map_section's
section_mem_map being treated as part of a bitmap which isn't good.  This
was evident with an invalid virtual address when mem_init attempted to free
bootmem pages while relinquishing control from the bootmem allocator.

The second part of the problem occurs because the pageblock flags bitmap is
be located with the mem_section.  The SECTIONS_PER_ROOT computation using
sizeof (mem_section) may not be a power of 2 depending on the size of the
bitmap.  This renders masks and other such things not power of 2 base.
This issue was seen with SPARSEMEM_EXTREME on ia64.  This patch moves the
bitmap outside of mem_section and uses a pointer instead in the
mem_section.  The bitmaps are allocated when the section is being
initialised.

Note that sparse_early_usemap_alloc() does not use alloc_remap() like
sparse_early_mem_map_alloc().  The allocation required for the bitmap on
x86, the only architecture that uses alloc_remap is typically smaller than
a cache line.  alloc_remap() pads out allocations to the cache size which
would be a needless waste.

Credit to Bob Picco for identifying the original problem and effecting a
fix for the SECTION_BLOCKFLAGS_BITS calculation.  Credit to Andy Whitcroft
for devising the best way of allocating the bitmaps only when required for
the section.

[wli@holomorphy.com: warning fix]
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: William Irwin <bill.irwin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:00 -07:00
Christoph Lameter
8f6aac419b Generic Virtual Memmap support for SPARSEMEM
SPARSEMEM is a pretty nice framework that unifies quite a bit of code over all
the arches.  It would be great if it could be the default so that we can get
rid of various forms of DISCONTIG and other variations on memory maps.  So far
what has hindered this are the additional lookups that SPARSEMEM introduces
for virt_to_page and page_address.  This goes so far that the code to do this
has to be kept in a separate function and cannot be used inline.

This patch introduces a virtual memmap mode for SPARSEMEM, in which the memmap
is mapped into a virtually contigious area, only the active sections are
physically backed.  This allows virt_to_page page_address and cohorts become
simple shift/add operations.  No page flag fields, no table lookups, nothing
involving memory is required.

The two key operations pfn_to_page and page_to_page become:

   #define __pfn_to_page(pfn)      (vmemmap + (pfn))
   #define __page_to_pfn(page)     ((page) - vmemmap)

By having a virtual mapping for the memmap we allow simple access without
wasting physical memory.  As kernel memory is typically already mapped 1:1
this introduces no additional overhead.  The virtual mapping must be big
enough to allow a struct page to be allocated and mapped for all valid
physical pages.  This vill make a virtual memmap difficult to use on 32 bit
platforms that support 36 address bits.

However, if there is enough virtual space available and the arch already maps
its 1-1 kernel space using TLBs (f.e.  true of IA64 and x86_64) then this
technique makes SPARSEMEM lookups even more efficient than CONFIG_FLATMEM.
FLATMEM needs to read the contents of the mem_map variable to get the start of
the memmap and then add the offset to the required entry.  vmemmap is a
constant to which we can simply add the offset.

This patch has the potential to allow us to make SPARSMEM the default (and
even the only) option for most systems.  It should be optimal on UP, SMP and
NUMA on most platforms.  Then we may even be able to remove the other memory
models: FLATMEM, DISCONTIG etc.

[apw@shadowen.org: config cleanups, resplit code etc]
[kamezawa.hiroyu@jp.fujitsu.com: Fix sparsemem_vmemmap init]
[apw@shadowen.org: vmemmap: remove excess debugging]
[apw@shadowen.org: simplify initialisation code and reduce duplication]
[apw@shadowen.org: pull out the vmemmap code into its own file]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:51 -07:00
Andy Whitcroft
540557b943 sparsemem: record when a section has a valid mem_map
We have flags to indicate whether a section actually has a valid mem_map
associated with it.  This is never set and we rely solely on the present bit
to indicate a section is valid.  By definition a section is not valid if it
has no mem_map and there is a window during init where the present bit is set
but there is no mem_map, during which pfn_valid() will return true
incorrectly.

Use the existing SECTION_HAS_MEM_MAP flag to indicate the presence of a valid
mem_map.  Switch valid_section{,_nr} and pfn_valid() to this bit.  Add a new
present_section{,_nr} and pfn_present() interfaces for those users who care to
know that a section is going to be valid.

[akpm@linux-foundation.org: coding-syle fixes]
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:51 -07:00
Andy Whitcroft
cd881a6b22 sparsemem: clean up spelling error in comments
SPARSEMEM is a pretty nice framework that unifies quite a bit of code over all
the arches.  It would be great if it could be the default so that we can get
rid of various forms of DISCONTIG and other variations on memory maps.  So far
what has hindered this are the additional lookups that SPARSEMEM introduces
for virt_to_page and page_address.  This goes so far that the code to do this
has to be kept in a separate function and cannot be used inline.

This patch introduces a virtual memmap mode for SPARSEMEM, in which the memmap
is mapped into a virtually contigious area, only the active sections are
physically backed.  This allows virt_to_page page_address and cohorts become
simple shift/add operations.  No page flag fields, no table lookups, nothing
involving memory is required.

The two key operations pfn_to_page and page_to_page become:

   #define __pfn_to_page(pfn)      (vmemmap + (pfn))
   #define __page_to_pfn(page)     ((page) - vmemmap)

By having a virtual mapping for the memmap we allow simple access without
wasting physical memory.  As kernel memory is typically already mapped 1:1
this introduces no additional overhead.  The virtual mapping must be big
enough to allow a struct page to be allocated and mapped for all valid
physical pages.  This vill make a virtual memmap difficult to use on 32 bit
platforms that support 36 address bits.

However, if there is enough virtual space available and the arch already maps
its 1-1 kernel space using TLBs (f.e.  true of IA64 and x86_64) then this
technique makes SPARSEMEM lookups even more efficient than CONFIG_FLATMEM.
FLATMEM needs to read the contents of the mem_map variable to get the start of
the memmap and then add the offset to the required entry.  vmemmap is a
constant to which we can simply add the offset.

This patch has the potential to allow us to make SPARSMEM the default (and
even the only) option for most systems.  It should be optimal on UP, SMP and
NUMA on most platforms.  Then we may even be able to remove the other memory
models: FLATMEM, DISCONTIG etc.

The current aim is to bring a common virtually mapped mem_map to all
architectures.  This should facilitate the removal of the bespoke
implementations from the architectures.  This also brings performance
improvements for most architecture making sparsmem vmemmap the more desirable
memory model.  The ultimate aim of this work is to expand sparsemem support to
encompass all the features of the other memory models.  This could allow us to
drop support for and remove the other models in the longer term.

Below are some comparitive kernbench numbers for various architectures,
comparing default memory model against SPARSEMEM VMEMMAP.  All but ia64 show
marginal improvement; we expect the ia64 figures to be sorted out when the
larger mapping support returns.

x86-64 non-NUMA
             Base    VMEMAP    % change (-ve good)
User        85.07     84.84    -0.26
System      34.32     33.84    -1.39
Total      119.38    118.68    -0.59

ia64
             Base    VMEMAP    % change (-ve good)
User      1016.41   1016.93    0.05
System      50.83     51.02    0.36
Total     1067.25   1067.95    0.07

x86-64 NUMA
             Base   VMEMAP    % change (-ve good)
User        30.77   431.73     0.22
System      45.39    43.98    -3.11
Total      476.17   475.71    -0.10

ppc64
             Base   VMEMAP    % change (-ve good)
User       488.77   488.35    -0.09
System      56.92    56.37    -0.97
Total      545.69   544.72    -0.18

Below are some AIM bencharks on IA64 and x86-64 (thank Bob).  The seems
pretty much flat as you would expect.

ia64 results 2 cpu non-numa 4Gb SCSI disk

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	extreme	Jun  1 07:17:24 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	98.9		100	58.9	1.3	1.6482
101	5547.1		95	106.0	79.4	0.9154
201	6377.7		95	183.4	158.3	0.5288
301	6932.2		95	252.7	237.3	0.3838
401	7075.8		93	329.8	316.7	0.2941
501	7235.6		94	403.0	396.2	0.2407
600	7387.5		94	472.7	475.0	0.2052

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	vmemmap	Jun  1 09:59:04 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	99.1		100	58.8	1.2	1.6509
101	5480.9		95	107.2	79.2	0.9044
201	6490.3		95	180.2	157.8	0.5382
301	6886.6		94	254.4	236.8	0.3813
401	7078.2		94	329.7	316.0	0.2942
501	7250.3		95	402.2	395.4	0.2412
600	7399.1		94	471.9	473.9	0.2055

open power 710 2 cpu, 4 Gb, SCSI and configured physically

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	extreme	May 29 15:42:53 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	25.7		100	226.3	4.3	0.4286
101	1096.0		97	536.4	199.8	0.1809
201	1236.4		96	946.1	389.1	0.1025
301	1280.5		96	1368.0	582.3	0.0709
401	1270.2		95	1837.4	771.0	0.0528
501	1251.4		96	2330.1	955.9	0.0416
601	1252.6		96	2792.4	1139.2	0.0347
701	1245.2		96	3276.5	1334.6	0.0296
918	1229.5		96	4345.4	1728.7	0.0223

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	vmemmap	May 30 07:28:26 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	25.6		100	226.9	4.3	0.4275
101	1049.3		97	560.2	198.1	0.1731
201	1199.1		97	975.6	390.7	0.0994
301	1261.7		96	1388.5	591.5	0.0699
401	1256.1		96	1858.1	771.9	0.0522
501	1220.1		96	2389.7	955.3	0.0406
601	1224.6		96	2856.3	1133.4	0.0340
701	1252.0		96	3258.7	1314.1	0.0298
915	1232.8		96	4319.7	1704.0	0.0225

amd64 2 2-core, 4Gb and SATA

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	extreme	Jun  2 03:59:48 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	13.0		100	446.4	2.1	0.2173
101	533.4		97	1102.0	110.2	0.0880
201	578.3		97	2022.8	220.8	0.0480
301	583.8		97	3000.6	332.3	0.0323
401	580.5		97	4020.1	442.2	0.0241
501	574.8		98	5072.8	558.8	0.0191
600	566.5		98	6163.8	671.0	0.0157

Benchmark	Version	Machine	Run Date
AIM Multiuser Benchmark - Suite VII	"1.1"	vmemmap	Jun  3 04:19:31 2007

Tasks	Jobs/Min	JTI	Real	CPU	Jobs/sec/task
1	13.0		100	447.8	2.0	0.2166
101	536.5		97	1095.6	109.7	0.0885
201	567.7		97	2060.5	219.3	0.0471
301	582.1		96	3009.4	330.2	0.0322
401	578.2		96	4036.4	442.4	0.0240
501	585.1		98	4983.2	555.1	0.0195
600	565.5		98	6175.2	660.6	0.0157

This patch:

Fix some spelling errors.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:51 -07:00
Andy Whitcroft
85770ffe4f sparsemem: ensure we initialise the node mapping for SPARSEMEM_STATIC
Booting SPARSEMEM on NUMA systems trips a BUG in page_alloc.c:

	Initializing HighMem for node 0 (00038000:00100000)
	Initializing HighMem for node 1 (00100000:001ffe00)
	------------[ cut here ]------------
	kernel BUG at /home/apw/git/linux-2.6/mm/page_alloc.c:456!
	[...]

This occurs because the section to node id mapping is not being
setup correctly during init under SPARSEMEM_STATIC, leading to an
attempt to free pages from all nodes into the zones on node 0.

When the zone_table[] was removed in the following commit, a new
section to node mapping table was introduced:

    commit 89689ae7f9
    [PATCH] Get rid of zone_table[]

That conversion inadvertantly only initialised the node mapping in
SPARSEMEM_EXTREME.  Ensure we initialise the node mapping in
SPARSEMEM_STATIC.

[akpm@linux-foundation.org: make the stubs static inline]
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-22 19:52:44 -07:00
Sam Ravnborg
dec2e6b7aa x86_64: fix section mismatch warning in init.c
Fix following warning:
WARNING: vmlinux.o(.text+0x188ea): Section mismatch: reference to .init.text:__alloc_bootmem_core (between 'alloc_bootmem_high_node' and 'get_gate_vma')

alloc_bootmem_high_node() is only used from __init scope so declare it __init.
And in addition declare the weak variant __init too.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-22 11:03:38 -07:00
Stephen Rothwell
193faea928 Move three functions that are only needed for CONFIG_MEMORY_HOTPLUG
into the appropriate #ifdef.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-08 17:23:33 -07:00
Zou Nan hai
2e1c49db4c x86_64: allocate sparsemem memmap above 4G
On systems with huge amount of physical memory, VFS cache and memory memmap
may eat all available system memory under 4G, then the system may fail to
allocate swiotlb bounce buffer.

There was a fix for this issue in arch/x86_64/mm/numa.c, but that fix dose
not cover sparsemem model.

This patch add fix to sparsemem model by first try to allocate memmap above
4G.

Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-01 08:18:27 -07:00
Sam Ravnborg
577a32f620 mm: fix section mismatch warnings
modpost had two cases hardcoded for mm/
Shift over to __init_refok and kill the
hardcoded function names in modpost.

This has the drawback that the functions
will always be kept no matter configuration.
With previous code the function were placed in
init section if configuration allowed it.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-19 09:11:58 +02:00
Yasunori Goto
72280ede31 Add white list into modpost.c for memory hotplug code and ia64's machvec section
This patch is add white list into modpost.c for some functions and
ia64's section to fix section mismatchs.

  sparse_index_alloc() and zone_wait_table_init() calls bootmem allocator
  at boot time, and kmalloc/vmalloc at hotplug time. If config
  memory hotplug is on, there are references of bootmem allocater(init text)
  from them (normal text). This is cause of section mismatch.

  Bootmem is called by many functions and it must be
  used only at boot time. I think __init of them should keep for
  section mismatch check. So, I would like to register sparse_index_alloc()
  and zone_wait_table_init() into white list.

  In addition, ia64's .machvec section is function table of some platform
  dependent code. It is mixture of .init.text and normal text. These
  reference of __init functions are valid too.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:14:57 -07:00