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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 08:07:57 -06:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_MEMORY_HOTPLUG_H
#define __LINUX_MEMORY_HOTPLUG_H
#include <linux/mmzone.h>
#include <linux/spinlock.h>
#include <linux/notifier.h>
#include <linux/bug.h>
struct page;
struct zone;
struct pglist_data;
struct mem_section;
struct memory_block;
struct resource;
struct vmem_altmap;
#ifdef CONFIG_MEMORY_HOTPLUG
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 16:37:56 -06:00
/*
* Return page for the valid pfn only if the page is online. All pfn
* walkers which rely on the fully initialized page->flags and others
* should use this rather than pfn_valid && pfn_to_page
*/
#define pfn_to_online_page(pfn) \
({ \
struct page *___page = NULL; \
unsigned long ___nr = pfn_to_section_nr(pfn); \
\
if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr))\
___page = pfn_to_page(pfn); \
___page; \
})
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 03:13:31 -06:00
/*
* Types for free bootmem stored in page->lru.next. These have to be in
* some random range in unsigned long space for debugging purposes.
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 03:13:31 -06:00
*/
enum {
MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,
SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
MIX_SECTION_INFO,
NODE_INFO,
MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
};
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 03:13:31 -06:00
/* Types for control the zone type of onlined and offlined memory */
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>
2012-12-11 17:03:16 -07:00
enum {
MMOP_OFFLINE = -1,
MMOP_ONLINE_KEEP,
MMOP_ONLINE_KERNEL,
MMOP_ONLINE_MOVABLE,
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>
2012-12-11 17:03:16 -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>
2012-12-11 17:03:16 -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.
*/
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);
}
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 */
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>
2012-12-11 17:03:16 -07:00
extern int online_pages(unsigned long, unsigned long, int);
base/memory, hotplug: fix a kernel oops in show_valid_zones() Reading a sysfs "memoryN/valid_zones" file leads to the following oops when the first page of a range is not backed by struct page. show_valid_zones() assumes that 'start_pfn' is always valid for page_zone(). BUG: unable to handle kernel paging request at ffffea017a000000 IP: show_valid_zones+0x6f/0x160 This issue may happen on x86-64 systems with 64GiB or more memory since their memory block size is bumped up to 2GiB. [1] An example of such systems is desribed below. 0x3240000000 is only aligned by 1GiB and this memory block starts from 0x3200000000, which is not backed by struct page. BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable Since test_pages_in_a_zone() already checks holes, fix this issue by extending this function to return 'valid_start' and 'valid_end' for a given range. show_valid_zones() then proceeds with the valid range. [1] 'Commit bdee237c0343 ("x86: mm: Use 2GB memory block size on large-memory x86-64 systems")' Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.com Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> [4.4+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-03 14:13:23 -07:00
extern int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
unsigned long *valid_start, unsigned long *valid_end);
extern void __offline_isolated_pages(unsigned long, unsigned long);
typedef void (*online_page_callback_t)(struct page *page);
extern int set_online_page_callback(online_page_callback_t callback);
extern int restore_online_page_callback(online_page_callback_t callback);
extern void __online_page_set_limits(struct page *page);
extern void __online_page_increment_counters(struct page *page);
extern void __online_page_free(struct page *page);
extern int try_online_node(int nid);
memory-hotplug: add automatic onlining policy for the newly added memory Currently, all newly added memory blocks remain in 'offline' state unless someone onlines them, some linux distributions carry special udev rules like: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online" to make this happen automatically. This is not a great solution for virtual machines where memory hotplug is being used to address high memory pressure situations as such onlining is slow and a userspace process doing this (udev) has a chance of being killed by the OOM killer as it will probably require to allocate some memory. Introduce default policy for the newly added memory blocks in /sys/devices/system/memory/auto_online_blocks file with two possible values: "offline" which preserves the current behavior and "online" which causes all newly added memory blocks to go online as soon as they're added. The default is "offline". Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: David Vrabel <david.vrabel@citrix.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 15:56:48 -06:00
extern bool memhp_auto_online;
/* If movable_node boot option specified */
extern bool movable_node_enabled;
static inline bool movable_node_is_enabled(void)
{
return movable_node_enabled;
}
memory-hotplug: add automatic onlining policy for the newly added memory Currently, all newly added memory blocks remain in 'offline' state unless someone onlines them, some linux distributions carry special udev rules like: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online" to make this happen automatically. This is not a great solution for virtual machines where memory hotplug is being used to address high memory pressure situations as such onlining is slow and a userspace process doing this (udev) has a chance of being killed by the OOM killer as it will probably require to allocate some memory. Introduce default policy for the newly added memory blocks in /sys/devices/system/memory/auto_online_blocks file with two possible values: "offline" which preserves the current behavior and "online" which causes all newly added memory blocks to go online as soon as they're added. The default is "offline". Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: David Vrabel <david.vrabel@citrix.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 15:56:48 -06:00
#ifdef CONFIG_MEMORY_HOTREMOVE
extern int arch_remove_memory(u64 start, u64 size,
struct vmem_altmap *altmap);
extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages, struct vmem_altmap *altmap);
#endif /* CONFIG_MEMORY_HOTREMOVE */
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 9d99aaa31f59 ("[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 511c2aba8f07 ("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 16:38:11 -06:00
/* reasonably generic interface to expand the physical pages */
extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
struct vmem_altmap *altmap, bool want_memblock);
mm/memory_hotplug: introduce add_pages There are new users of memory hotplug emerging. Some of them require different subset of arch_add_memory. There are some which only require allocation of struct pages without mapping those pages to the kernel address space. We currently have __add_pages for that purpose. But this is rather lowlevel and not very suitable for the code outside of the memory hotplug. E.g. x86_64 wants to update max_pfn which should be done by the caller. Introduce add_pages() which should care about those details if they are needed. Each architecture should define its implementation and select CONFIG_ARCH_HAS_ADD_PAGES. All others use the currently existing __add_pages. Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Nellans <dnellans@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Sherry Cheung <SCheung@nvidia.com> Cc: Subhash Gutti <sgutti@nvidia.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Bob Liu <liubo95@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 17:11:39 -06:00
#ifndef CONFIG_ARCH_HAS_ADD_PAGES
static inline int add_pages(int nid, unsigned long start_pfn,
unsigned long nr_pages, struct vmem_altmap *altmap,
bool want_memblock)
mm/memory_hotplug: introduce add_pages There are new users of memory hotplug emerging. Some of them require different subset of arch_add_memory. There are some which only require allocation of struct pages without mapping those pages to the kernel address space. We currently have __add_pages for that purpose. But this is rather lowlevel and not very suitable for the code outside of the memory hotplug. E.g. x86_64 wants to update max_pfn which should be done by the caller. Introduce add_pages() which should care about those details if they are needed. Each architecture should define its implementation and select CONFIG_ARCH_HAS_ADD_PAGES. All others use the currently existing __add_pages. Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Nellans <dnellans@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Sherry Cheung <SCheung@nvidia.com> Cc: Subhash Gutti <sgutti@nvidia.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Bob Liu <liubo95@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 17:11:39 -06:00
{
return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
mm/memory_hotplug: introduce add_pages There are new users of memory hotplug emerging. Some of them require different subset of arch_add_memory. There are some which only require allocation of struct pages without mapping those pages to the kernel address space. We currently have __add_pages for that purpose. But this is rather lowlevel and not very suitable for the code outside of the memory hotplug. E.g. x86_64 wants to update max_pfn which should be done by the caller. Introduce add_pages() which should care about those details if they are needed. Each architecture should define its implementation and select CONFIG_ARCH_HAS_ADD_PAGES. All others use the currently existing __add_pages. Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Nellans <dnellans@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Sherry Cheung <SCheung@nvidia.com> Cc: Subhash Gutti <sgutti@nvidia.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Bob Liu <liubo95@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 17:11:39 -06:00
}
#else /* ARCH_HAS_ADD_PAGES */
int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
struct vmem_altmap *altmap, bool want_memblock);
mm/memory_hotplug: introduce add_pages There are new users of memory hotplug emerging. Some of them require different subset of arch_add_memory. There are some which only require allocation of struct pages without mapping those pages to the kernel address space. We currently have __add_pages for that purpose. But this is rather lowlevel and not very suitable for the code outside of the memory hotplug. E.g. x86_64 wants to update max_pfn which should be done by the caller. Introduce add_pages() which should care about those details if they are needed. Each architecture should define its implementation and select CONFIG_ARCH_HAS_ADD_PAGES. All others use the currently existing __add_pages. Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Nellans <dnellans@nvidia.com> Cc: Evgeny Baskakov <ebaskakov@nvidia.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mark Hairgrove <mhairgrove@nvidia.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Sherry Cheung <SCheung@nvidia.com> Cc: Subhash Gutti <sgutti@nvidia.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Bob Liu <liubo95@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 17:11:39 -06:00
#endif /* ARCH_HAS_ADD_PAGES */
#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
#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.
*
*/
extern pg_data_t *arch_alloc_nodedata(int nid);
extern void arch_free_nodedata(pg_data_t *pgdat);
extern void arch_refresh_nodedata(int nid, pg_data_t *pgdat);
#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)
extern pg_data_t *node_data[];
static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
{
node_data[nid] = pgdat;
}
#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)
{
}
static inline void arch_refresh_nodedata(int nid, pg_data_t *pgdat)
{
}
#endif /* CONFIG_NUMA */
#endif /* CONFIG_HAVE_ARCH_NODEDATA_EXTENSION */
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.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: 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: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-22 17:33:00 -07:00
#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
extern void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.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: 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: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-22 17:33:00 -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 03:13:31 -06:00
static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
{
}
#endif
memory-hotplug: implement register_page_bootmem_info_section of sparse-vmemmap For removing memmap region of sparse-vmemmap which is allocated bootmem, memmap region of sparse-vmemmap needs to be registered by get_page_bootmem(). So the patch searches pages of virtual mapping and registers the pages by get_page_bootmem(). NOTE: register_page_bootmem_memmap() is not implemented for ia64, ppc, s390, and sparc. So introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node() when platform doesn't support it. It's implemented by adding a new Kconfig option named CONFIG_HAVE_BOOTMEM_INFO_NODE, which will be automatically selected by memory-hotplug feature fully supported archs(currently only on x86_64). Since we have 2 config options called MEMORY_HOTPLUG and MEMORY_HOTREMOVE used for memory hot-add and hot-remove separately, and codes in function register_page_bootmem_info_node() are only used for collecting infomation for hot-remove, so reside it under MEMORY_HOTREMOVE. Besides page_isolation.c selected by MEMORY_ISOLATION under MEMORY_HOTPLUG is also such case, move it too. [mhocko@suse.cz: put register_page_bootmem_memmap inside CONFIG_MEMORY_HOTPLUG_SPARSE] [linfeng@cn.fujitsu.com: introduce CONFIG_HAVE_BOOTMEM_INFO_NODE and revert register_page_bootmem_info_node()] [mhocko@suse.cz: remove the arch specific functions without any implementation] [linfeng@cn.fujitsu.com: mm/Kconfig: move auto selects from MEMORY_HOTPLUG to MEMORY_HOTREMOVE as needed] [rientjes@google.com: fix defined but not used warning] Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Wu Jianguo <wujianguo@huawei.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.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: 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: Lin Feng <linfeng@cn.fujitsu.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-22 17:33:00 -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 03:13:31 -06:00
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>
2014-06-04 17:07:18 -06:00
void get_online_mems(void);
void put_online_mems(void);
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:45:11 -06:00
void mem_hotplug_begin(void);
void mem_hotplug_done(void);
Revert "mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE" This reverts the following commits that change CMA design in MM. 3d2054ad8c2d ("ARM: CMA: avoid double mapping to the CMA area if CONFIG_HIGHMEM=y") 1d47a3ec09b5 ("mm/cma: remove ALLOC_CMA") bad8c6c0b114 ("mm/cma: manage the memory of the CMA area by using the ZONE_MOVABLE") Ville reported a following error on i386. Inode-cache hash table entries: 65536 (order: 6, 262144 bytes) microcode: microcode updated early to revision 0x4, date = 2013-06-28 Initializing CPU#0 Initializing HighMem for node 0 (000377fe:00118000) Initializing Movable for node 0 (00000001:00118000) BUG: Bad page state in process swapper pfn:377fe page:f53effc0 count:0 mapcount:-127 mapping:00000000 index:0x0 flags: 0x80000000() raw: 80000000 00000000 00000000 ffffff80 00000000 00000100 00000200 00000001 page dumped because: nonzero mapcount Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 4.17.0-rc5-elk+ #145 Hardware name: Dell Inc. Latitude E5410/03VXMC, BIOS A15 07/11/2013 Call Trace: dump_stack+0x60/0x96 bad_page+0x9a/0x100 free_pages_check_bad+0x3f/0x60 free_pcppages_bulk+0x29d/0x5b0 free_unref_page_commit+0x84/0xb0 free_unref_page+0x3e/0x70 __free_pages+0x1d/0x20 free_highmem_page+0x19/0x40 add_highpages_with_active_regions+0xab/0xeb set_highmem_pages_init+0x66/0x73 mem_init+0x1b/0x1d7 start_kernel+0x17a/0x363 i386_start_kernel+0x95/0x99 startup_32_smp+0x164/0x168 The reason for this error is that the span of MOVABLE_ZONE is extended to whole node span for future CMA initialization, and, normal memory is wrongly freed here. I submitted the fix and it seems to work, but, another problem happened. It's so late time to fix the later problem so I decide to reverting the series. Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Acked-by: Laura Abbott <labbott@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-22 19:18:21 -06:00
extern void set_zone_contiguous(struct zone *zone);
extern void clear_zone_contiguous(struct zone *zone);
#else /* ! CONFIG_MEMORY_HOTPLUG */
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 16:37:56 -06:00
#define pfn_to_online_page(pfn) \
({ \
struct page *___page = NULL; \
if (pfn_valid(pfn)) \
___page = pfn_to_page(pfn); \
___page; \
})
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) {}
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 03:13:31 -06:00
static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
{
}
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>
2014-06-04 17:07:18 -06:00
static inline void get_online_mems(void) {}
static inline void put_online_mems(void) {}
mm, hotplug: fix concurrent memory hot-add deadlock There's a deadlock when concurrently hot-adding memory through the probe interface and switching a memory block from offline to online. When hot-adding memory via the probe interface, add_memory() first takes mem_hotplug_begin() and then device_lock() is later taken when registering the newly initialized memory block. This creates a lock dependency of (1) mem_hotplug.lock (2) dev->mutex. When switching a memory block from offline to online, dev->mutex is first grabbed in device_online() when the write(2) transitions an existing memory block from offline to online, and then online_pages() will take mem_hotplug_begin(). This creates a lock inversion between mem_hotplug.lock and dev->mutex. Vitaly reports that this deadlock can happen when kworker handling a probe event races with systemd-udevd switching a memory block's state. This patch requires the state transition to take mem_hotplug_begin() before dev->mutex. Hot-adding memory via the probe interface creates a memory block while holding mem_hotplug_begin(), there is no way to take dev->mutex first in this case. online_pages() and offline_pages() are only called when transitioning memory block state. We now require that mem_hotplug_begin() is taken before calling them -- this requires exporting the mem_hotplug_begin() and mem_hotplug_done() to generic code. In all hot-add and hot-remove cases, mem_hotplug_begin() is done prior to device_online(). This is all that is needed to avoid the deadlock. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-14 16:45:11 -06:00
static inline void mem_hotplug_begin(void) {}
static inline void mem_hotplug_done(void) {}
static inline bool movable_node_is_enabled(void)
{
return false;
}
#endif /* ! CONFIG_MEMORY_HOTPLUG */
mm: disable interrupts while initializing deferred pages Vlastimil Babka reported about a window issue during which when deferred pages are initialized, and the current version of on-demand initialization is finished, allocations may fail. While this is highly unlikely scenario, since this kind of allocation request must be large, and must come from interrupt handler, we still want to cover it. We solve this by initializing deferred pages with interrupts disabled, and holding node_size_lock spin lock while pages in the node are being initialized. The on-demand deferred page initialization that comes later will use the same lock, and thus synchronize with deferred_init_memmap(). It is unlikely for threads that initialize deferred pages to be interrupted. They run soon after smp_init(), but before modules are initialized, and long before user space programs. This is why there is no adverse effect of having these threads running with interrupts disabled. [pasha.tatashin@oracle.com: v6] Link: http://lkml.kernel.org/r/20180313182355.17669-2-pasha.tatashin@oracle.com Link: http://lkml.kernel.org/r/20180309220807.24961-2-pasha.tatashin@oracle.com Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Steven Sistare <steven.sistare@oracle.com> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Gioh Kim <gi-oh.kim@profitbricks.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yaowei Bai <baiyaowei@cmss.chinamobile.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 17:22:27 -06:00
#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) */
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-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>
2008-07-23 22:28:19 -06:00
#ifdef CONFIG_MEMORY_HOTREMOVE
extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages);
extern void try_offline_node(int nid);
extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
extern void 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>
2018-10-30 16:10:18 -06:00
extern void __remove_memory(int nid, u64 start, u64 size);
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-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>
2008-07-23 22:28:19 -06:00
#else
static inline bool is_mem_section_removable(unsigned long pfn,
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-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>
2008-07-23 22:28:19 -06:00
unsigned long nr_pages)
{
return false;
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-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>
2008-07-23 22:28:19 -06:00
}
static inline void try_offline_node(int nid) {}
static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
{
return -EINVAL;
}
static inline void 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>
2018-10-30 16:10:18 -06:00
static inline void __remove_memory(int nid, u64 start, u64 size) {}
memory-hotplug: add sysfs removable attribute for hotplug memory remove Memory may be hot-removed on a per-memory-block basis, particularly on POWER where the SPARSEMEM section size often matches the memory-block size. A user-level agent must be able to identify which sections of memory are likely to be removable before attempting the potentially expensive operation. This patch adds a file called "removable" to the memory directory in sysfs to help such an agent. In this patch, a memory block is considered removable if; o It contains only MOVABLE pageblocks o It contains only pageblocks with free pages regardless of pageblock type On the other hand, a memory block starting with a PageReserved() page will never be considered removable. Without this patch, the user-agent is forced to choose a memory block to remove randomly. Sample output of the sysfs files: ./memory/memory0/removable: 0 ./memory/memory1/removable: 0 ./memory/memory2/removable: 0 ./memory/memory3/removable: 0 ./memory/memory4/removable: 0 ./memory/memory5/removable: 0 ./memory/memory6/removable: 0 ./memory/memory7/removable: 1 ./memory/memory8/removable: 0 ./memory/memory9/removable: 0 ./memory/memory10/removable: 0 ./memory/memory11/removable: 0 ./memory/memory12/removable: 0 ./memory/memory13/removable: 0 ./memory/memory14/removable: 0 ./memory/memory15/removable: 0 ./memory/memory16/removable: 0 ./memory/memory17/removable: 1 ./memory/memory18/removable: 1 ./memory/memory19/removable: 1 ./memory/memory20/removable: 1 ./memory/memory21/removable: 1 ./memory/memory22/removable: 1 Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-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>
2008-07-23 22:28:19 -06:00
#endif /* CONFIG_MEMORY_HOTREMOVE */
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>
2018-08-21 22:53:43 -06:00
extern void __ref free_area_init_core_hotplug(int nid);
extern int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
void *arg, int (*func)(struct memory_block *, void *));
mm/memory_hotplug: make add_memory() take the device_hotplug_lock add_memory() currently does not take the device_hotplug_lock, however is aleady called under the lock from arch/powerpc/platforms/pseries/hotplug-memory.c drivers/acpi/acpi_memhotplug.c to synchronize against CPU hot-remove and similar. In general, we should hold the device_hotplug_lock when adding memory to synchronize against online/offline request (e.g. from user space) - which already resulted in lock inversions due to device_lock() and mem_hotplug_lock - see 30467e0b3be ("mm, hotplug: fix concurrent memory hot-add deadlock"). add_memory()/add_memory_resource() will create memory block devices, so this really feels like the right thing to do. Holding the device_hotplug_lock makes sure that a memory block device can really only be accessed (e.g. via .online/.state) from user space, once the memory has been fully added to the system. The lock is not held yet in drivers/xen/balloon.c arch/powerpc/platforms/powernv/memtrace.c drivers/s390/char/sclp_cmd.c drivers/hv/hv_balloon.c So, let's either use the locked variants or take the lock. Don't export add_memory_resource(), as it once was exported to be used by XEN, which is never built as a module. If somebody requires it, we also have to export a locked variant (as device_hotplug_lock is never exported). Link: http://lkml.kernel.org/r/20180925091457.28651-3-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: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.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: Mathieu Malaterre <malat@debian.org> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Neuling <mikey@neuling.org> 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>
2018-10-30 16:10:24 -06:00
extern int __add_memory(int nid, u64 start, u64 size);
extern int add_memory(int nid, u64 start, u64 size);
memory-hotplug: add automatic onlining policy for the newly added memory Currently, all newly added memory blocks remain in 'offline' state unless someone onlines them, some linux distributions carry special udev rules like: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online" to make this happen automatically. This is not a great solution for virtual machines where memory hotplug is being used to address high memory pressure situations as such onlining is slow and a userspace process doing this (udev) has a chance of being killed by the OOM killer as it will probably require to allocate some memory. Introduce default policy for the newly added memory blocks in /sys/devices/system/memory/auto_online_blocks file with two possible values: "offline" which preserves the current behavior and "online" which causes all newly added memory blocks to go online as soon as they're added. The default is "offline". Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: David Vrabel <david.vrabel@citrix.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 15:56:48 -06:00
extern int add_memory_resource(int nid, struct resource *resource, bool online);
extern int arch_add_memory(int nid, u64 start, u64 size,
struct vmem_altmap *altmap, bool want_memblock);
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 9d99aaa31f59 ("[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 511c2aba8f07 ("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 16:38:11 -06:00
extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
unsigned long nr_pages, struct vmem_altmap *altmap);
extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages);
memory-hotplug: check whether all memory blocks are offlined or not when removing memory We remove the memory like this: 1. lock memory hotplug 2. offline a memory block 3. unlock memory hotplug 4. repeat 1-3 to offline all memory blocks 5. lock memory hotplug 6. remove memory(TODO) 7. unlock memory hotplug All memory blocks must be offlined before removing memory. But we don't hold the lock in the whole operation. So we should check whether all memory blocks are offlined before step6. Otherwise, kernel maybe panicked. Offlining a memory block and removing a memory device can be two different operations. Users can just offline some memory blocks without removing the memory device. For this purpose, the kernel has held lock_memory_hotplug() in __offline_pages(). To reuse the code for memory hot-remove, we repeat step 1-3 to offline all the memory blocks, repeatedly lock and unlock memory hotplug, but not hold the memory hotplug lock in the whole operation. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Tang Chen <tangchen@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: 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: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-22 17:32:52 -07:00
extern bool is_memblock_offlined(struct memory_block *mem);
extern int sparse_add_one_section(struct pglist_data *pgdat,
unsigned long start_pfn, struct vmem_altmap *altmap);
extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms,
unsigned long map_offset, struct vmem_altmap *altmap);
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 03:13:31 -06:00
extern struct page *sparse_decode_mem_map(unsigned long coded_mem_map,
unsigned long pnum);
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 9d99aaa31f59 ("[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 511c2aba8f07 ("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 16:38:11 -06:00
extern bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages,
int online_type);
mm, memory_hotplug: display allowed zones in the preferred ordering Prior to commit f1dd2cd13c4b ("mm, memory_hotplug: do not associate hotadded memory to zones until online") we used to allow to change the valid zone types of a memory block if it is adjacent to a different zone type. This fact was reflected in memoryNN/valid_zones by the ordering of printed zones. The first one was default (echo online > memoryNN/state) and the other one could be onlined explicitly by online_{movable,kernel}. This behavior was removed by the said patch and as such the ordering was not all that important. In most cases a kernel zone would be default anyway. The only exception is movable_node handled by "mm, memory_hotplug: support movable_node for hotpluggable nodes". Let's reintroduce this behavior again because later patch will remove the zone overlap restriction and so user will be allowed to online kernel resp. movable block regardless of its placement. Original behavior will then become significant again because it would be non-trivial for users to see what is the default zone to online into. Implementation is really simple. Pull out zone selection out of move_pfn_range into zone_for_pfn_range helper and use it in show_valid_zones to display the zone for default onlining and then both kernel and movable if they are allowed. Default online zone is not duplicated. Link: http://lkml.kernel.org/r/20170714121233.16861-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Cc: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Cc: Xishi Qiu <qiuxishi@huawei.com> Cc: Kani Toshimitsu <toshi.kani@hpe.com> Cc: <slaoub@gmail.com> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wei Yang <richard.weiyang@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:19:37 -06:00
extern struct zone *zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
mm, memory_hotplug: do not assume ZONE_NORMAL is default kernel zone Heiko Carstens has noticed that he can generate overlapping zones for ZONE_DMA and ZONE_NORMAL: DMA [mem 0x0000000000000000-0x000000007fffffff] Normal [mem 0x0000000080000000-0x000000017fffffff] $ cat /sys/devices/system/memory/block_size_bytes 10000000 $ cat /sys/devices/system/memory/memory5/valid_zones DMA $ echo 0 > /sys/devices/system/memory/memory5/online $ cat /sys/devices/system/memory/memory5/valid_zones Normal $ echo 1 > /sys/devices/system/memory/memory5/online Normal $ cat /proc/zoneinfo Node 0, zone DMA spanned 524288 <----- present 458752 managed 455078 start_pfn: 0 <----- Node 0, zone Normal spanned 720896 present 589824 managed 571648 start_pfn: 327680 <----- The reason is that we assume that the default zone for kernel onlining is ZONE_NORMAL. This was a simplification introduced by the memory hotplug rework and it is easily fixable by checking the range overlap in the zone order and considering the first matching zone as the default one. If there is no such zone then assume ZONE_NORMAL as we have been doing so far. Fixes: "mm, memory_hotplug: do not associate hotadded memory to zones until online" Link: http://lkml.kernel.org/r/20170601083746.4924-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com> Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Reza Arbab <arbab@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:38:18 -06:00
unsigned long nr_pages);
#endif /* __LINUX_MEMORY_HOTPLUG_H */