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>
2017-11-01 21:07:57 +07:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2005-10-30 08:16:52 +07:00
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#ifndef __LINUX_MEMORY_HOTPLUG_H
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#define __LINUX_MEMORY_HOTPLUG_H
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#include <linux/mmzone.h>
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#include <linux/spinlock.h>
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2005-10-30 08:16:54 +07:00
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#include <linux/notifier.h>
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2011-11-24 08:12:59 +07:00
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#include <linux/bug.h>
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2005-10-30 08:16:52 +07:00
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2006-03-07 06:42:49 +07:00
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struct page;
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struct zone;
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struct pglist_data;
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2008-04-28 16:12:01 +07:00
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struct mem_section;
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2012-10-09 06:34:01 +07:00
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struct memory_block;
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2015-06-25 22:35:49 +07:00
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struct resource;
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2017-12-29 14:53:53 +07:00
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struct vmem_altmap;
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2006-03-07 06:42:49 +07:00
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2005-10-30 08:16:52 +07:00
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#ifdef CONFIG_MEMORY_HOTPLUG
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2017-07-07 05:37:56 +07:00
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/*
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* Return page for the valid pfn only if the page is online. All pfn
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* walkers which rely on the fully initialized page->flags and others
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* should use this rather than pfn_valid && pfn_to_page
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*/
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mm/hotplug: invalid PFNs from pfn_to_online_page()
On an arm64 ThunderX2 server, the first kmemleak scan would crash [1]
with CONFIG_DEBUG_VM_PGFLAGS=y due to page_to_nid() found a pfn that is
not directly mapped (MEMBLOCK_NOMAP). Hence, the page->flags is
uninitialized.
This is due to the commit 9f1eb38e0e11 ("mm, kmemleak: little
optimization while scanning") starts to use pfn_to_online_page() instead
of pfn_valid(). However, in the CONFIG_MEMORY_HOTPLUG=y case,
pfn_to_online_page() does not call memblock_is_map_memory() while
pfn_valid() does.
Historically, the commit 68709f45385a ("arm64: only consider memblocks
with NOMAP cleared for linear mapping") causes pages marked as nomap
being no long reassigned to the new zone in memmap_init_zone() by
calling __init_single_page().
Since the commit 2d070eab2e82 ("mm: consider zone which is not fully
populated to have holes") introduced pfn_to_online_page() and was
designed to return a valid pfn only, but it is clearly broken on arm64.
Therefore, let pfn_to_online_page() call pfn_valid_within(), so it can
handle nomap thanks to the commit f52bb98f5ade ("arm64: mm: always
enable CONFIG_HOLES_IN_ZONE"), while it will be optimized away on
architectures where have no HOLES_IN_ZONE.
[1]
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000006
Mem abort info:
ESR = 0x96000005
Exception class = DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000005
CM = 0, WnR = 0
Internal error: Oops: 96000005 [#1] SMP
CPU: 60 PID: 1408 Comm: kmemleak Not tainted 5.0.0-rc2+ #8
pstate: 60400009 (nZCv daif +PAN -UAO)
pc : page_mapping+0x24/0x144
lr : __dump_page+0x34/0x3dc
sp : ffff00003a5cfd10
x29: ffff00003a5cfd10 x28: 000000000000802f
x27: 0000000000000000 x26: 0000000000277d00
x25: ffff000010791f56 x24: ffff7fe000000000
x23: ffff000010772f8b x22: ffff00001125f670
x21: ffff000011311000 x20: ffff000010772f8b
x19: fffffffffffffffe x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: ffff802698b19600
x13: ffff802698b1a200 x12: ffff802698b16f00
x11: ffff802698b1a400 x10: 0000000000001400
x9 : 0000000000000001 x8 : ffff00001121a000
x7 : 0000000000000000 x6 : ffff0000102c53b8
x5 : 0000000000000000 x4 : 0000000000000003
x3 : 0000000000000100 x2 : 0000000000000000
x1 : ffff000010772f8b x0 : ffffffffffffffff
Process kmemleak (pid: 1408, stack limit = 0x(____ptrval____))
Call trace:
page_mapping+0x24/0x144
__dump_page+0x34/0x3dc
dump_page+0x28/0x4c
kmemleak_scan+0x4ac/0x680
kmemleak_scan_thread+0xb4/0xdc
kthread+0x12c/0x13c
ret_from_fork+0x10/0x18
Code: d503201f f9400660 36000040 d1000413 (f9400661)
---[ end trace 4d4bd7f573490c8e ]---
Kernel panic - not syncing: Fatal exception
SMP: stopping secondary CPUs
Kernel Offset: disabled
CPU features: 0x002,20000c38
Memory Limit: none
---[ end Kernel panic - not syncing: Fatal exception ]---
Link: http://lkml.kernel.org/r/20190122132916.28360-1-cai@lca.pw
Fixes: 9f1eb38e0e11 ("mm, kmemleak: little optimization while scanning")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-02 05:20:51 +07:00
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#define pfn_to_online_page(pfn) \
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({ \
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struct page *___page = NULL; \
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unsigned long ___pfn = pfn; \
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unsigned long ___nr = pfn_to_section_nr(___pfn); \
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\
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if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr) && \
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pfn_valid_within(___pfn)) \
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___page = pfn_to_page(___pfn); \
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___page; \
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2017-07-07 05:37:56 +07:00
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})
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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 16:13:31 +07:00
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/*
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2011-01-14 06:47:00 +07:00
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* Types for free bootmem stored in page->lru.next. These have to be in
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* some random range in unsigned long space for debugging purposes.
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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 16:13:31 +07:00
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*/
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2011-01-14 06:47:00 +07:00
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enum {
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MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
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SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
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MIX_SECTION_INFO,
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NODE_INFO,
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MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
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};
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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 16:13:31 +07:00
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2014-08-07 06:05:13 +07:00
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/* Types for control the zone type of onlined and offlined memory */
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mm, memory-hotplug: dynamic configure movable memory and portion memory
Add online_movable and online_kernel for logic memory hotplug. This is
the dynamic version of "movablecore" & "kernelcore".
We have the same reason to introduce it as to introduce "movablecore" &
"kernelcore". It has the same motive as "movablecore" & "kernelcore", but
it is dynamic/running-time:
o We can configure memory as kernelcore or movablecore after boot.
Userspace workload is increased, we need more hugepage, we can't use
"online_movable" to add memory and allow the system use more
THP(transparent-huge-page), vice-verse when kernel workload is increase.
Also help for virtualization to dynamic configure host/guest's memory,
to save/(reduce waste) memory.
Memory capacity on Demand
o When a new node is physically online after boot, we need to use
"online_movable" or "online_kernel" to configure/portion it as we
expected when we logic-online it.
This configuration also helps for physically-memory-migrate.
o all benefit as the same as existed "movablecore" & "kernelcore".
o Preparing for movable-node, which is very important for power-saving,
hardware partitioning and high-available-system(hardware fault
management).
(Note, we don't introduce movable-node here.)
Action behavior:
When a memoryblock/memorysection is onlined by "online_movable", the kernel
will not have directly reference to the page of the memoryblock,
thus we can remove that memory any time when needed.
When it is online by "online_kernel", the kernel can use it.
When it is online by "online", the zone type doesn't changed.
Current constraints:
Only the memoryblock which is adjacent to the ZONE_MOVABLE
can be online from ZONE_NORMAL to ZONE_MOVABLE.
[akpm@linux-foundation.org: use min_t, cleanups]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 07:03:16 +07:00
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enum {
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2014-08-07 06:05:13 +07:00
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MMOP_OFFLINE = -1,
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MMOP_ONLINE_KEEP,
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MMOP_ONLINE_KERNEL,
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MMOP_ONLINE_MOVABLE,
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mm, memory-hotplug: dynamic configure movable memory and portion memory
Add online_movable and online_kernel for logic memory hotplug. This is
the dynamic version of "movablecore" & "kernelcore".
We have the same reason to introduce it as to introduce "movablecore" &
"kernelcore". It has the same motive as "movablecore" & "kernelcore", but
it is dynamic/running-time:
o We can configure memory as kernelcore or movablecore after boot.
Userspace workload is increased, we need more hugepage, we can't use
"online_movable" to add memory and allow the system use more
THP(transparent-huge-page), vice-verse when kernel workload is increase.
Also help for virtualization to dynamic configure host/guest's memory,
to save/(reduce waste) memory.
Memory capacity on Demand
o When a new node is physically online after boot, we need to use
"online_movable" or "online_kernel" to configure/portion it as we
expected when we logic-online it.
This configuration also helps for physically-memory-migrate.
o all benefit as the same as existed "movablecore" & "kernelcore".
o Preparing for movable-node, which is very important for power-saving,
hardware partitioning and high-available-system(hardware fault
management).
(Note, we don't introduce movable-node here.)
Action behavior:
When a memoryblock/memorysection is onlined by "online_movable", the kernel
will not have directly reference to the page of the memoryblock,
thus we can remove that memory any time when needed.
When it is online by "online_kernel", the kernel can use it.
When it is online by "online", the zone type doesn't changed.
Current constraints:
Only the memoryblock which is adjacent to the ZONE_MOVABLE
can be online from ZONE_NORMAL to ZONE_MOVABLE.
[akpm@linux-foundation.org: use min_t, cleanups]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 07:03:16 +07:00
|
|
|
};
|
|
|
|
|
|
2019-05-14 07:21:26 +07:00
|
|
|
/*
|
|
|
|
|
* Restrictions for the memory hotplug:
|
|
|
|
|
* flags: MHP_ flags
|
|
|
|
|
* altmap: alternative allocator for memmap array
|
|
|
|
|
*/
|
|
|
|
|
struct mhp_restrictions {
|
|
|
|
|
unsigned long flags;
|
|
|
|
|
struct vmem_altmap *altmap;
|
|
|
|
|
};
|
|
|
|
|
|
2005-10-30 08:16:53 +07:00
|
|
|
/*
|
|
|
|
|
* Zone resizing functions
|
mm, memory-hotplug: dynamic configure movable memory and portion memory
Add online_movable and online_kernel for logic memory hotplug. This is
the dynamic version of "movablecore" & "kernelcore".
We have the same reason to introduce it as to introduce "movablecore" &
"kernelcore". It has the same motive as "movablecore" & "kernelcore", but
it is dynamic/running-time:
o We can configure memory as kernelcore or movablecore after boot.
Userspace workload is increased, we need more hugepage, we can't use
"online_movable" to add memory and allow the system use more
THP(transparent-huge-page), vice-verse when kernel workload is increase.
Also help for virtualization to dynamic configure host/guest's memory,
to save/(reduce waste) memory.
Memory capacity on Demand
o When a new node is physically online after boot, we need to use
"online_movable" or "online_kernel" to configure/portion it as we
expected when we logic-online it.
This configuration also helps for physically-memory-migrate.
o all benefit as the same as existed "movablecore" & "kernelcore".
o Preparing for movable-node, which is very important for power-saving,
hardware partitioning and high-available-system(hardware fault
management).
(Note, we don't introduce movable-node here.)
Action behavior:
When a memoryblock/memorysection is onlined by "online_movable", the kernel
will not have directly reference to the page of the memoryblock,
thus we can remove that memory any time when needed.
When it is online by "online_kernel", the kernel can use it.
When it is online by "online", the zone type doesn't changed.
Current constraints:
Only the memoryblock which is adjacent to the ZONE_MOVABLE
can be online from ZONE_NORMAL to ZONE_MOVABLE.
[akpm@linux-foundation.org: use min_t, cleanups]
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-12 07:03:16 +07:00
|
|
|
*
|
|
|
|
|
* Note: any attempt to resize a zone should has pgdat_resize_lock()
|
|
|
|
|
* zone_span_writelock() both held. This ensure the size of a zone
|
|
|
|
|
* can't be changed while pgdat_resize_lock() held.
|
2005-10-30 08:16:53 +07:00
|
|
|
*/
|
|
|
|
|
static inline unsigned zone_span_seqbegin(struct zone *zone)
|
|
|
|
|
{
|
|
|
|
|
return read_seqbegin(&zone->span_seqlock);
|
|
|
|
|
}
|
|
|
|
|
static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
|
|
|
|
|
{
|
|
|
|
|
return read_seqretry(&zone->span_seqlock, iv);
|
|
|
|
|
}
|
|
|
|
|
static inline void zone_span_writelock(struct zone *zone)
|
|
|
|
|
{
|
|
|
|
|
write_seqlock(&zone->span_seqlock);
|
|
|
|
|
}
|
|
|
|
|
static inline void zone_span_writeunlock(struct zone *zone)
|
|
|
|
|
{
|
|
|
|
|
write_sequnlock(&zone->span_seqlock);
|
|
|
|
|
}
|
|
|
|
|
static inline void zone_seqlock_init(struct zone *zone)
|
|
|
|
|
{
|
|
|
|
|
seqlock_init(&zone->span_seqlock);
|
|
|
|
|
}
|
2005-10-30 08:16:54 +07:00
|
|
|
extern int zone_grow_free_lists(struct zone *zone, unsigned long new_nr_pages);
|
|
|
|
|
extern int zone_grow_waitqueues(struct zone *zone, unsigned long nr_pages);
|
|
|
|
|
extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
|
|
|
|
|
/* VM interface that may be used by firmware interface */
|
2020-01-31 13:14:54 +07:00
|
|
|
extern int online_pages(unsigned long pfn, unsigned long nr_pages,
|
|
|
|
|
int online_type, int nid);
|
2020-02-04 08:34:26 +07:00
|
|
|
extern struct zone *test_pages_in_a_zone(unsigned long start_pfn,
|
|
|
|
|
unsigned long end_pfn);
|
2019-05-14 07:21:24 +07:00
|
|
|
extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
|
|
|
|
|
unsigned long end_pfn);
|
2007-10-16 15:26:14 +07:00
|
|
|
|
2019-03-06 06:42:14 +07:00
|
|
|
typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
|
2011-07-26 07:12:05 +07:00
|
|
|
|
2019-12-01 08:53:51 +07:00
|
|
|
extern void generic_online_page(struct page *page, unsigned int order);
|
2011-07-26 07:12:05 +07:00
|
|
|
extern int set_online_page_callback(online_page_callback_t callback);
|
|
|
|
|
extern int restore_online_page_callback(online_page_callback_t callback);
|
|
|
|
|
|
2013-11-13 06:07:25 +07:00
|
|
|
extern int try_online_node(int nid);
|
|
|
|
|
|
2019-05-14 07:21:26 +07:00
|
|
|
extern int arch_add_memory(int nid, u64 start, u64 size,
|
|
|
|
|
struct mhp_restrictions *restrictions);
|
2019-02-14 17:42:39 +07:00
|
|
|
extern u64 max_mem_size;
|
|
|
|
|
|
2016-03-16 04:56:48 +07:00
|
|
|
extern bool memhp_auto_online;
|
2017-07-07 05:41:05 +07:00
|
|
|
/* If movable_node boot option specified */
|
|
|
|
|
extern bool movable_node_enabled;
|
|
|
|
|
static inline bool movable_node_is_enabled(void)
|
|
|
|
|
{
|
|
|
|
|
return movable_node_enabled;
|
|
|
|
|
}
|
2016-03-16 04:56:48 +07:00
|
|
|
|
2019-05-14 07:21:46 +07:00
|
|
|
extern void arch_remove_memory(int nid, u64 start, u64 size,
|
|
|
|
|
struct vmem_altmap *altmap);
|
2020-01-05 03:59:33 +07:00
|
|
|
extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
|
|
|
|
|
struct vmem_altmap *altmap);
|
2010-10-27 04:21:30 +07:00
|
|
|
|
2017-07-07 05:38:11 +07:00
|
|
|
/* reasonably generic interface to expand the physical pages */
|
2017-12-29 14:53:53 +07:00
|
|
|
extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
|
2019-05-14 07:21:26 +07:00
|
|
|
struct mhp_restrictions *restrictions);
|
2006-06-27 16:53:30 +07:00
|
|
|
|
2017-09-09 06:11:39 +07:00
|
|
|
#ifndef CONFIG_ARCH_HAS_ADD_PAGES
|
|
|
|
|
static inline int add_pages(int nid, unsigned long start_pfn,
|
2019-05-14 07:21:26 +07:00
|
|
|
unsigned long nr_pages, struct mhp_restrictions *restrictions)
|
2017-09-09 06:11:39 +07:00
|
|
|
{
|
2019-05-14 07:21:26 +07:00
|
|
|
return __add_pages(nid, start_pfn, nr_pages, restrictions);
|
2017-09-09 06:11:39 +07:00
|
|
|
}
|
|
|
|
|
#else /* ARCH_HAS_ADD_PAGES */
|
2017-12-29 14:53:53 +07:00
|
|
|
int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
|
2019-05-14 07:21:26 +07:00
|
|
|
struct mhp_restrictions *restrictions);
|
2017-09-09 06:11:39 +07:00
|
|
|
#endif /* ARCH_HAS_ADD_PAGES */
|
|
|
|
|
|
2006-06-27 16:53:30 +07:00
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
|
extern int memory_add_physaddr_to_nid(u64 start);
|
|
|
|
|
#else
|
|
|
|
|
static inline int memory_add_physaddr_to_nid(u64 start)
|
|
|
|
|
{
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
#endif
|
|
|
|
|
|
2006-06-27 16:53:32 +07:00
|
|
|
#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION
|
|
|
|
|
/*
|
|
|
|
|
* For supporting node-hotadd, we have to allocate a new pgdat.
|
|
|
|
|
*
|
|
|
|
|
* If an arch has generic style NODE_DATA(),
|
|
|
|
|
* node_data[nid] = kzalloc() works well. But it depends on the architecture.
|
|
|
|
|
*
|
|
|
|
|
* In general, generic_alloc_nodedata() is used.
|
|
|
|
|
* Now, arch_free_nodedata() is just defined for error path of node_hot_add.
|
|
|
|
|
*
|
|
|
|
|
*/
|
2006-06-27 16:53:40 +07:00
|
|
|
extern pg_data_t *arch_alloc_nodedata(int nid);
|
|
|
|
|
extern void arch_free_nodedata(pg_data_t *pgdat);
|
[PATCH] pgdat allocation and update for ia64 of memory hotplug: update pgdat address array
This is to refresh node_data[] array for ia64. As I mentioned previous
patches, ia64 has copies of information of pgdat address array on each node as
per node data.
At v2 of node_add, this function used stop_machine_run() to update them. (I
wished that they were copied safety as much as possible.) But, in this patch,
this arrays are just copied simply, and set node_online_map bit after
completion of pgdat initialization.
So, kernel must touch NODE_DATA() macro after checking node_online_map().
(Current code has already done it.) This is more simple way for just
hot-add.....
Note : It will be problem when hot-remove will occur,
because, even if online_map bit is set, kernel may
touch NODE_DATA() due to race condition. :-(
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 16:53:39 +07:00
|
|
|
extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
|
2006-06-27 16:53:32 +07:00
|
|
|
|
|
|
|
|
#else /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
|
|
|
|
|
|
|
|
|
|
#define arch_alloc_nodedata(nid) generic_alloc_nodedata(nid)
|
|
|
|
|
#define arch_free_nodedata(pgdat) generic_free_nodedata(pgdat)
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
|
/*
|
|
|
|
|
* If ARCH_HAS_NODEDATA_EXTENSION=n, this func is used to allocate pgdat.
|
|
|
|
|
* XXX: kmalloc_node() can't work well to get new node's memory at this time.
|
|
|
|
|
* Because, pgdat for the new node is not allocated/initialized yet itself.
|
|
|
|
|
* To use new node's memory, more consideration will be necessary.
|
|
|
|
|
*/
|
|
|
|
|
#define generic_alloc_nodedata(nid) \
|
|
|
|
|
({ \
|
|
|
|
|
kzalloc(sizeof(pg_data_t), GFP_KERNEL); \
|
|
|
|
|
})
|
|
|
|
|
/*
|
|
|
|
|
* This definition is just for error path in node hotadd.
|
|
|
|
|
* For node hotremove, we have to replace this.
|
|
|
|
|
*/
|
|
|
|
|
#define generic_free_nodedata(pgdat) kfree(pgdat)
|
|
|
|
|
|
2006-06-27 16:53:33 +07:00
|
|
|
extern pg_data_t *node_data[];
|
|
|
|
|
static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
|
|
|
|
|
{
|
|
|
|
|
node_data[nid] = pgdat;
|
|
|
|
|
}
|
|
|
|
|
|
2006-06-27 16:53:32 +07:00
|
|
|
#else /* !CONFIG_NUMA */
|
|
|
|
|
|
|
|
|
|
/* never called */
|
|
|
|
|
static inline pg_data_t *generic_alloc_nodedata(int nid)
|
|
|
|
|
{
|
|
|
|
|
BUG();
|
|
|
|
|
return NULL;
|
|
|
|
|
}
|
|
|
|
|
static inline void generic_free_nodedata(pg_data_t *pgdat)
|
|
|
|
|
{
|
|
|
|
|
}
|
2006-06-27 16:53:33 +07:00
|
|
|
static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
|
|
|
|
|
{
|
|
|
|
|
}
|
2006-06-27 16:53:32 +07:00
|
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
|
#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
|
|
|
|
|
|
2013-02-23 07:33:00 +07:00
|
|
|
#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
|
2016-05-28 05:23:32 +07:00
|
|
|
extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
|
2013-02-23 07:33:00 +07:00
|
|
|
#else
|
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 16:13:31 +07:00
|
|
|
static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
|
|
|
|
|
{
|
|
|
|
|
}
|
|
|
|
|
#endif
|
2013-02-23 07:33:00 +07:00
|
|
|
extern void put_page_bootmem(struct page *page);
|
|
|
|
|
extern void get_page_bootmem(unsigned long ingo, struct page *page,
|
|
|
|
|
unsigned long type);
|
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 16:13:31 +07:00
|
|
|
|
mem-hotplug: implement get/put_online_mems
kmem_cache_{create,destroy,shrink} need to get a stable value of
cpu/node online mask, because they init/destroy/access per-cpu/node
kmem_cache parts, which can be allocated or destroyed on cpu/mem
hotplug. To protect against cpu hotplug, these functions use
{get,put}_online_cpus. However, they do nothing to synchronize with
memory hotplug - taking the slab_mutex does not eliminate the
possibility of race as described in patch 2.
What we need there is something like get_online_cpus, but for memory.
We already have lock_memory_hotplug, which serves for the purpose, but
it's a bit of a hammer right now, because it's backed by a mutex. As a
result, it imposes some limitations to locking order, which are not
desirable, and can't be used just like get_online_cpus. That's why in
patch 1 I substitute it with get/put_online_mems, which work exactly
like get/put_online_cpus except they block not cpu, but memory hotplug.
[ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by
myself, because it used an rw semaphore for get/put_online_mems,
making them dead lock prune. ]
This patch (of 2):
{un}lock_memory_hotplug, which is used to synchronize against memory
hotplug, is currently backed by a mutex, which makes it a bit of a
hammer - threads that only want to get a stable value of online nodes
mask won't be able to proceed concurrently. Also, it imposes some
strong locking ordering rules on it, which narrows down the set of its
usage scenarios.
This patch introduces get/put_online_mems, which are the same as
get/put_online_cpus, but for memory hotplug, i.e. executing a code
inside a get/put_online_mems section will guarantee a stable value of
online nodes, present pages, etc.
lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-05 06:07:18 +07:00
|
|
|
void get_online_mems(void);
|
|
|
|
|
void put_online_mems(void);
|
2010-12-03 05:31:19 +07:00
|
|
|
|
2015-04-15 05:45:11 +07:00
|
|
|
void mem_hotplug_begin(void);
|
|
|
|
|
void mem_hotplug_done(void);
|
|
|
|
|
|
2005-10-30 08:16:52 +07:00
|
|
|
#else /* ! CONFIG_MEMORY_HOTPLUG */
|
2017-07-07 05:37:56 +07:00
|
|
|
#define pfn_to_online_page(pfn) \
|
|
|
|
|
({ \
|
|
|
|
|
struct page *___page = NULL; \
|
|
|
|
|
if (pfn_valid(pfn)) \
|
|
|
|
|
___page = pfn_to_page(pfn); \
|
|
|
|
|
___page; \
|
|
|
|
|
})
|
|
|
|
|
|
2005-10-30 08:16:53 +07:00
|
|
|
static inline unsigned zone_span_seqbegin(struct zone *zone)
|
|
|
|
|
{
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
static inline int zone_span_seqretry(struct zone *zone, unsigned iv)
|
|
|
|
|
{
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
static inline void zone_span_writelock(struct zone *zone) {}
|
|
|
|
|
static inline void zone_span_writeunlock(struct zone *zone) {}
|
|
|
|
|
static inline void zone_seqlock_init(struct zone *zone) {}
|
2005-10-30 08:16:54 +07:00
|
|
|
|
|
|
|
|
static inline int mhp_notimplemented(const char *func)
|
|
|
|
|
{
|
|
|
|
|
printk(KERN_WARNING "%s() called, with CONFIG_MEMORY_HOTPLUG disabled\n", func);
|
|
|
|
|
dump_stack();
|
|
|
|
|
return -ENOSYS;
|
|
|
|
|
}
|
|
|
|
|
|
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 16:13:31 +07:00
|
|
|
static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
|
|
|
|
|
{
|
|
|
|
|
}
|
|
|
|
|
|
2013-11-13 06:07:25 +07:00
|
|
|
static inline int try_online_node(int nid)
|
|
|
|
|
{
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
|
|
|
|
|
mem-hotplug: implement get/put_online_mems
kmem_cache_{create,destroy,shrink} need to get a stable value of
cpu/node online mask, because they init/destroy/access per-cpu/node
kmem_cache parts, which can be allocated or destroyed on cpu/mem
hotplug. To protect against cpu hotplug, these functions use
{get,put}_online_cpus. However, they do nothing to synchronize with
memory hotplug - taking the slab_mutex does not eliminate the
possibility of race as described in patch 2.
What we need there is something like get_online_cpus, but for memory.
We already have lock_memory_hotplug, which serves for the purpose, but
it's a bit of a hammer right now, because it's backed by a mutex. As a
result, it imposes some limitations to locking order, which are not
desirable, and can't be used just like get_online_cpus. That's why in
patch 1 I substitute it with get/put_online_mems, which work exactly
like get/put_online_cpus except they block not cpu, but memory hotplug.
[ v1 can be found at https://lkml.org/lkml/2014/4/6/68. I NAK'ed it by
myself, because it used an rw semaphore for get/put_online_mems,
making them dead lock prune. ]
This patch (of 2):
{un}lock_memory_hotplug, which is used to synchronize against memory
hotplug, is currently backed by a mutex, which makes it a bit of a
hammer - threads that only want to get a stable value of online nodes
mask won't be able to proceed concurrently. Also, it imposes some
strong locking ordering rules on it, which narrows down the set of its
usage scenarios.
This patch introduces get/put_online_mems, which are the same as
get/put_online_cpus, but for memory hotplug, i.e. executing a code
inside a get/put_online_mems section will guarantee a stable value of
online nodes, present pages, etc.
lock_memory_hotplug()/unlock_memory_hotplug() are removed altogether.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-05 06:07:18 +07:00
|
|
|
static inline void get_online_mems(void) {}
|
|
|
|
|
static inline void put_online_mems(void) {}
|
2010-12-03 05:31:19 +07:00
|
|
|
|
2015-04-15 05:45:11 +07:00
|
|
|
static inline void mem_hotplug_begin(void) {}
|
|
|
|
|
static inline void mem_hotplug_done(void) {}
|
|
|
|
|
|
2017-07-07 05:41:05 +07:00
|
|
|
static inline bool movable_node_is_enabled(void)
|
|
|
|
|
{
|
|
|
|
|
return false;
|
|
|
|
|
}
|
2005-10-30 08:16:53 +07:00
|
|
|
#endif /* ! CONFIG_MEMORY_HOTPLUG */
|
2006-04-08 00:49:15 +07:00
|
|
|
|
2018-04-06 06:22:27 +07:00
|
|
|
#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)
|
|
|
|
|
/*
|
|
|
|
|
* pgdat resizing functions
|
|
|
|
|
*/
|
|
|
|
|
static inline
|
|
|
|
|
void pgdat_resize_lock(struct pglist_data *pgdat, unsigned long *flags)
|
|
|
|
|
{
|
|
|
|
|
spin_lock_irqsave(&pgdat->node_size_lock, *flags);
|
|
|
|
|
}
|
|
|
|
|
static inline
|
|
|
|
|
void pgdat_resize_unlock(struct pglist_data *pgdat, unsigned long *flags)
|
|
|
|
|
{
|
|
|
|
|
spin_unlock_irqrestore(&pgdat->node_size_lock, *flags);
|
|
|
|
|
}
|
|
|
|
|
static inline
|
|
|
|
|
void pgdat_resize_init(struct pglist_data *pgdat)
|
|
|
|
|
{
|
|
|
|
|
spin_lock_init(&pgdat->node_size_lock);
|
|
|
|
|
}
|
|
|
|
|
#else /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
|
|
|
|
|
/*
|
|
|
|
|
* Stub functions for when hotplug is off
|
|
|
|
|
*/
|
|
|
|
|
static inline void pgdat_resize_lock(struct pglist_data *p, unsigned long *f) {}
|
|
|
|
|
static inline void pgdat_resize_unlock(struct pglist_data *p, unsigned long *f) {}
|
|
|
|
|
static inline void pgdat_resize_init(struct pglist_data *pgdat) {}
|
|
|
|
|
#endif /* !(CONFIG_MEMORY_HOTPLUG || CONFIG_DEFERRED_STRUCT_PAGE_INIT) */
|
|
|
|
|
|
2008-07-24 11:28:19 +07:00
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
|
|
|
|
2016-05-20 07:11:26 +07:00
|
|
|
extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
|
2013-02-23 07:33:27 +07:00
|
|
|
extern void try_offline_node(int nid);
|
2013-06-02 03:24:07 +07:00
|
|
|
extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
|
2019-07-17 06:30:31 +07:00
|
|
|
extern int remove_memory(int nid, u64 start, u64 size);
|
mm/memory_hotplug: make remove_memory() take the device_hotplug_lock
Patch series "mm: online/offline_pages called w.o. mem_hotplug_lock", v3.
Reading through the code and studying how mem_hotplug_lock is to be used,
I noticed that there are two places where we can end up calling
device_online()/device_offline() - online_pages()/offline_pages() without
the mem_hotplug_lock. And there are other places where we call
device_online()/device_offline() without the device_hotplug_lock.
While e.g.
echo "online" > /sys/devices/system/memory/memory9/state
is fine, e.g.
echo 1 > /sys/devices/system/memory/memory9/online
Will not take the mem_hotplug_lock. However the device_lock() and
device_hotplug_lock.
E.g. via memory_probe_store(), we can end up calling
add_memory()->online_pages() without the device_hotplug_lock. So we can
have concurrent callers in online_pages(). We e.g. touch in
online_pages() basically unprotected zone->present_pages then.
Looks like there is a longer history to that (see Patch #2 for details),
and fixing it to work the way it was intended is not really possible. We
would e.g. have to take the mem_hotplug_lock in device/base/core.c, which
sounds wrong.
Summary: We had a lock inversion on mem_hotplug_lock and device_lock().
More details can be found in patch 3 and patch 6.
I propose the general rules (documentation added in patch 6):
1. add_memory/add_memory_resource() must only be called with
device_hotplug_lock.
2. remove_memory() must only be called with device_hotplug_lock. This is
already documented and holds for all callers.
3. device_online()/device_offline() must only be called with
device_hotplug_lock. This is already documented and true for now in core
code. Other callers (related to memory hotplug) have to be fixed up.
4. mem_hotplug_lock is taken inside of add_memory/remove_memory/
online_pages/offline_pages.
To me, this looks way cleaner than what we have right now (and easier to
verify). And looking at the documentation of remove_memory, using
lock_device_hotplug also for add_memory() feels natural.
This patch (of 6):
remove_memory() is exported right now but requires the
device_hotplug_lock, which is not exported. So let's provide a variant
that takes the lock and only export that one.
The lock is already held in
arch/powerpc/platforms/pseries/hotplug-memory.c
drivers/acpi/acpi_memhotplug.c
arch/powerpc/platforms/powernv/memtrace.c
Apart from that, there are not other users in the tree.
Link: http://lkml.kernel.org/r/20180925091457.28651-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Rashmica Gupta <rashmica.g@gmail.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 05:10:18 +07:00
|
|
|
extern void __remove_memory(int nid, u64 start, u64 size);
|
2008-07-24 11:28:19 +07:00
|
|
|
|
|
|
|
|
#else
|
2016-05-20 07:11:26 +07:00
|
|
|
static inline bool is_mem_section_removable(unsigned long pfn,
|
2008-07-24 11:28:19 +07:00
|
|
|
unsigned long nr_pages)
|
|
|
|
|
{
|
2016-05-20 07:11:26 +07:00
|
|
|
return false;
|
2008-07-24 11:28:19 +07:00
|
|
|
}
|
2013-02-23 07:33:27 +07:00
|
|
|
|
|
|
|
|
static inline void try_offline_node(int nid) {}
|
2013-06-02 03:24:07 +07:00
|
|
|
|
|
|
|
|
static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
|
|
|
|
|
{
|
|
|
|
|
return -EINVAL;
|
|
|
|
|
}
|
|
|
|
|
|
2019-07-17 06:30:31 +07:00
|
|
|
static inline int remove_memory(int nid, u64 start, u64 size)
|
|
|
|
|
{
|
|
|
|
|
return -EBUSY;
|
|
|
|
|
}
|
|
|
|
|
|
mm/memory_hotplug: make remove_memory() take the device_hotplug_lock
Patch series "mm: online/offline_pages called w.o. mem_hotplug_lock", v3.
Reading through the code and studying how mem_hotplug_lock is to be used,
I noticed that there are two places where we can end up calling
device_online()/device_offline() - online_pages()/offline_pages() without
the mem_hotplug_lock. And there are other places where we call
device_online()/device_offline() without the device_hotplug_lock.
While e.g.
echo "online" > /sys/devices/system/memory/memory9/state
is fine, e.g.
echo 1 > /sys/devices/system/memory/memory9/online
Will not take the mem_hotplug_lock. However the device_lock() and
device_hotplug_lock.
E.g. via memory_probe_store(), we can end up calling
add_memory()->online_pages() without the device_hotplug_lock. So we can
have concurrent callers in online_pages(). We e.g. touch in
online_pages() basically unprotected zone->present_pages then.
Looks like there is a longer history to that (see Patch #2 for details),
and fixing it to work the way it was intended is not really possible. We
would e.g. have to take the mem_hotplug_lock in device/base/core.c, which
sounds wrong.
Summary: We had a lock inversion on mem_hotplug_lock and device_lock().
More details can be found in patch 3 and patch 6.
I propose the general rules (documentation added in patch 6):
1. add_memory/add_memory_resource() must only be called with
device_hotplug_lock.
2. remove_memory() must only be called with device_hotplug_lock. This is
already documented and holds for all callers.
3. device_online()/device_offline() must only be called with
device_hotplug_lock. This is already documented and true for now in core
code. Other callers (related to memory hotplug) have to be fixed up.
4. mem_hotplug_lock is taken inside of add_memory/remove_memory/
online_pages/offline_pages.
To me, this looks way cleaner than what we have right now (and easier to
verify). And looking at the documentation of remove_memory, using
lock_device_hotplug also for add_memory() feels natural.
This patch (of 6):
remove_memory() is exported right now but requires the
device_hotplug_lock, which is not exported. So let's provide a variant
that takes the lock and only export that one.
The lock is already held in
arch/powerpc/platforms/pseries/hotplug-memory.c
drivers/acpi/acpi_memhotplug.c
arch/powerpc/platforms/powernv/memtrace.c
Apart from that, there are not other users in the tree.
Link: http://lkml.kernel.org/r/20180925091457.28651-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Rashmica Gupta <rashmica.g@gmail.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: Mathieu Malaterre <malat@debian.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 05:10:18 +07:00
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static inline void __remove_memory(int nid, u64 start, u64 size) {}
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2008-07-24 11:28:19 +07:00
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#endif /* CONFIG_MEMORY_HOTREMOVE */
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2019-12-01 08:54:10 +07:00
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extern void set_zone_contiguous(struct zone *zone);
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extern void clear_zone_contiguous(struct zone *zone);
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mm/page_alloc: Introduce free_area_init_core_hotplug
Currently, whenever a new node is created/re-used from the memhotplug
path, we call free_area_init_node()->free_area_init_core(). But there is
some code that we do not really need to run when we are coming from such
path.
free_area_init_core() performs the following actions:
1) Initializes pgdat internals, such as spinlock, waitqueues and more.
2) Account # nr_all_pages and # nr_kernel_pages. These values are used later on
when creating hash tables.
3) Account number of managed_pages per zone, substracting dma_reserved and
memmap pages.
4) Initializes some fields of the zone structure data
5) Calls init_currently_empty_zone to initialize all the freelists
6) Calls memmap_init to initialize all pages belonging to certain zone
When called from memhotplug path, free_area_init_core() only performs
actions #1 and #4.
Action #2 is pointless as the zones do not have any pages since either the
node was freed, or we are re-using it, eitherway all zones belonging to
this node should have 0 pages. For the same reason, action #3 results
always in manages_pages being 0.
Action #5 and #6 are performed later on when onlining the pages:
online_pages()->move_pfn_range_to_zone()->init_currently_empty_zone()
online_pages()->move_pfn_range_to_zone()->memmap_init_zone()
This patch does two things:
First, moves the node/zone initializtion to their own function, so it
allows us to create a small version of free_area_init_core, where we only
perform:
1) Initialization of pgdat internals, such as spinlock, waitqueues and more
4) Initialization of some fields of the zone structure data
These two functions are: pgdat_init_internals() and zone_init_internals().
The second thing this patch does, is to introduce
free_area_init_core_hotplug(), the memhotplug version of
free_area_init_core():
Currently, we call free_area_init_node() from the memhotplug path. In
there, we set some pgdat's fields, and call calculate_node_totalpages().
calculate_node_totalpages() calculates the # of pages the node has.
Since the node is either new, or we are re-using it, the zones belonging
to this node should not have any pages, so there is no point to calculate
this now.
Actually, we re-set these values to 0 later on with the calls to:
reset_node_managed_pages()
reset_node_present_pages()
The # of pages per node and the # of pages per zone will be calculated when
onlining the pages:
online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_zone_range()
online_pages()->move_pfn_range()->move_pfn_range_to_zone()->resize_pgdat_range()
Also, since free_area_init_core/free_area_init_node will now only get called during early init, let us replace
__paginginit with __init, so their code gets freed up.
[osalvador@techadventures.net: fix section usage]
Link: http://lkml.kernel.org/r/20180731101752.GA473@techadventures.net
[osalvador@suse.de: v6]
Link: http://lkml.kernel.org/r/20180801122348.21588-6-osalvador@techadventures.net
Link: http://lkml.kernel.org/r/20180730101757.28058-5-osalvador@techadventures.net
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Pasha Tatashin <Pavel.Tatashin@microsoft.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 11:53:43 +07:00
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extern void __ref free_area_init_core_hotplug(int nid);
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2018-10-31 05:10:24 +07:00
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extern int __add_memory(int nid, u64 start, u64 size);
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2006-06-27 16:53:30 +07:00
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extern int add_memory(int nid, u64 start, u64 size);
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2018-12-28 15:35:36 +07:00
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extern int add_memory_resource(int nid, struct resource *resource);
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2017-07-07 05:38:11 +07:00
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extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
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2017-12-29 14:53:57 +07:00
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unsigned long nr_pages, struct vmem_altmap *altmap);
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2020-01-05 03:59:33 +07:00
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extern void remove_pfn_range_from_zone(struct zone *zone,
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unsigned long start_pfn,
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unsigned long nr_pages);
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2013-02-23 07:32:52 +07:00
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extern bool is_memblock_offlined(struct memory_block *mem);
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2019-07-19 05:58:22 +07:00
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extern int sparse_add_section(int nid, unsigned long pfn,
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unsigned long nr_pages, struct vmem_altmap *altmap);
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2019-07-19 05:58:26 +07:00
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extern void sparse_remove_section(struct mem_section *ms,
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2019-07-19 05:58:22 +07:00
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unsigned long pfn, unsigned long nr_pages,
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2017-12-29 14:53:56 +07:00
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unsigned long map_offset, struct vmem_altmap *altmap);
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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 16:13:31 +07:00
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extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
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unsigned long pnum);
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2017-07-07 05:38:11 +07:00
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extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
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int online_type);
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2017-09-07 06:19:37 +07:00
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extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
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2017-07-07 05:38:18 +07:00
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unsigned long nr_pages);
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2005-10-30 08:16:52 +07:00
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#endif /* __LINUX_MEMORY_HOTPLUG_H */
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