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![Oscar Salvador](/assets/img/avatar_default.png)
This patch, as the previous one, gets rid of the wrong if statements. While at it, I realized that the comments are sometimes very confusing, to say the least, and wrong. For example: ___ zone_last = ZONE_MOVABLE; /* * check whether node_states[N_HIGH_MEMORY] will be changed * If we try to offline the last present @nr_pages from the node, * we can determind we will need to clear the node from * node_states[N_HIGH_MEMORY]. */ for (; zt <= zone_last; zt++) present_pages += pgdat->node_zones[zt].present_pages; if (nr_pages >= present_pages) arg->status_change_nid = zone_to_nid(zone); else arg->status_change_nid = -1; ___ In case the node gets empry, it must be removed from N_MEMORY. We already check N_HIGH_MEMORY a bit above within the CONFIG_HIGHMEM ifdef code. Not to say that status_change_nid is for N_MEMORY, and not for N_HIGH_MEMORY. So I re-wrote some of the comments to what I think is better. [osalvador@suse.de: address feedback from Pavel] Link: http://lkml.kernel.org/r/20180921132634.10103-5-osalvador@techadventures.net Link: http://lkml.kernel.org/r/20180919100819.25518-6-osalvador@techadventures.net Signed-off-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: <yasu.isimatu@gmail.com> Cc: Mathieu Malaterre <malat@debian.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1840 lines
47 KiB
C
1840 lines
47 KiB
C
/*
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* linux/mm/memory_hotplug.c
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*
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* Copyright (C)
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*/
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#include <linux/stddef.h>
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#include <linux/mm.h>
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#include <linux/sched/signal.h>
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#include <linux/swap.h>
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#include <linux/interrupt.h>
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#include <linux/pagemap.h>
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#include <linux/compiler.h>
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#include <linux/export.h>
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#include <linux/pagevec.h>
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#include <linux/writeback.h>
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#include <linux/slab.h>
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#include <linux/sysctl.h>
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#include <linux/cpu.h>
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#include <linux/memory.h>
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#include <linux/memremap.h>
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#include <linux/memory_hotplug.h>
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#include <linux/highmem.h>
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#include <linux/vmalloc.h>
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#include <linux/ioport.h>
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#include <linux/delay.h>
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#include <linux/migrate.h>
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#include <linux/page-isolation.h>
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#include <linux/pfn.h>
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#include <linux/suspend.h>
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#include <linux/mm_inline.h>
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#include <linux/firmware-map.h>
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#include <linux/stop_machine.h>
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#include <linux/hugetlb.h>
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#include <linux/memblock.h>
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#include <linux/bootmem.h>
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#include <linux/compaction.h>
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#include <asm/tlbflush.h>
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#include "internal.h"
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/*
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* online_page_callback contains pointer to current page onlining function.
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* Initially it is generic_online_page(). If it is required it could be
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* changed by calling set_online_page_callback() for callback registration
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* and restore_online_page_callback() for generic callback restore.
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*/
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static void generic_online_page(struct page *page);
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static online_page_callback_t online_page_callback = generic_online_page;
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static DEFINE_MUTEX(online_page_callback_lock);
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DEFINE_STATIC_PERCPU_RWSEM(mem_hotplug_lock);
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void get_online_mems(void)
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{
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percpu_down_read(&mem_hotplug_lock);
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}
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void put_online_mems(void)
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{
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percpu_up_read(&mem_hotplug_lock);
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}
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bool movable_node_enabled = false;
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#ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
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bool memhp_auto_online;
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#else
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bool memhp_auto_online = true;
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#endif
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EXPORT_SYMBOL_GPL(memhp_auto_online);
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static int __init setup_memhp_default_state(char *str)
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{
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if (!strcmp(str, "online"))
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memhp_auto_online = true;
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else if (!strcmp(str, "offline"))
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memhp_auto_online = false;
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return 1;
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}
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__setup("memhp_default_state=", setup_memhp_default_state);
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void mem_hotplug_begin(void)
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{
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cpus_read_lock();
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percpu_down_write(&mem_hotplug_lock);
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}
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void mem_hotplug_done(void)
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{
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percpu_up_write(&mem_hotplug_lock);
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cpus_read_unlock();
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}
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/* add this memory to iomem resource */
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static struct resource *register_memory_resource(u64 start, u64 size)
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{
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struct resource *res, *conflict;
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res = kzalloc(sizeof(struct resource), GFP_KERNEL);
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if (!res)
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return ERR_PTR(-ENOMEM);
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res->name = "System RAM";
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res->start = start;
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res->end = start + size - 1;
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res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
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conflict = request_resource_conflict(&iomem_resource, res);
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if (conflict) {
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if (conflict->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) {
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pr_debug("Device unaddressable memory block "
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"memory hotplug at %#010llx !\n",
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(unsigned long long)start);
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}
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pr_debug("System RAM resource %pR cannot be added\n", res);
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kfree(res);
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return ERR_PTR(-EEXIST);
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}
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return res;
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}
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static void release_memory_resource(struct resource *res)
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{
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if (!res)
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return;
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release_resource(res);
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kfree(res);
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return;
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}
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#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
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void get_page_bootmem(unsigned long info, struct page *page,
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unsigned long type)
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{
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page->freelist = (void *)type;
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SetPagePrivate(page);
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set_page_private(page, info);
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page_ref_inc(page);
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}
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void put_page_bootmem(struct page *page)
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{
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unsigned long type;
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type = (unsigned long) page->freelist;
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BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||
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type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);
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if (page_ref_dec_return(page) == 1) {
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page->freelist = NULL;
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ClearPagePrivate(page);
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set_page_private(page, 0);
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INIT_LIST_HEAD(&page->lru);
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free_reserved_page(page);
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}
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}
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#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
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#ifndef CONFIG_SPARSEMEM_VMEMMAP
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static void register_page_bootmem_info_section(unsigned long start_pfn)
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{
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unsigned long *usemap, mapsize, section_nr, i;
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struct mem_section *ms;
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struct page *page, *memmap;
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section_nr = pfn_to_section_nr(start_pfn);
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ms = __nr_to_section(section_nr);
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/* Get section's memmap address */
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memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
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/*
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* Get page for the memmap's phys address
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* XXX: need more consideration for sparse_vmemmap...
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*/
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page = virt_to_page(memmap);
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mapsize = sizeof(struct page) * PAGES_PER_SECTION;
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mapsize = PAGE_ALIGN(mapsize) >> PAGE_SHIFT;
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/* remember memmap's page */
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for (i = 0; i < mapsize; i++, page++)
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get_page_bootmem(section_nr, page, SECTION_INFO);
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usemap = ms->pageblock_flags;
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page = virt_to_page(usemap);
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mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
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for (i = 0; i < mapsize; i++, page++)
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get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
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}
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#else /* CONFIG_SPARSEMEM_VMEMMAP */
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static void register_page_bootmem_info_section(unsigned long start_pfn)
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{
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unsigned long *usemap, mapsize, section_nr, i;
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struct mem_section *ms;
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struct page *page, *memmap;
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section_nr = pfn_to_section_nr(start_pfn);
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ms = __nr_to_section(section_nr);
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memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr);
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register_page_bootmem_memmap(section_nr, memmap, PAGES_PER_SECTION);
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usemap = ms->pageblock_flags;
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page = virt_to_page(usemap);
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mapsize = PAGE_ALIGN(usemap_size()) >> PAGE_SHIFT;
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for (i = 0; i < mapsize; i++, page++)
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get_page_bootmem(section_nr, page, MIX_SECTION_INFO);
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}
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#endif /* !CONFIG_SPARSEMEM_VMEMMAP */
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void __init register_page_bootmem_info_node(struct pglist_data *pgdat)
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{
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unsigned long i, pfn, end_pfn, nr_pages;
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int node = pgdat->node_id;
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struct page *page;
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nr_pages = PAGE_ALIGN(sizeof(struct pglist_data)) >> PAGE_SHIFT;
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page = virt_to_page(pgdat);
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for (i = 0; i < nr_pages; i++, page++)
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get_page_bootmem(node, page, NODE_INFO);
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pfn = pgdat->node_start_pfn;
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end_pfn = pgdat_end_pfn(pgdat);
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/* register section info */
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for (; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
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/*
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* Some platforms can assign the same pfn to multiple nodes - on
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* node0 as well as nodeN. To avoid registering a pfn against
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* multiple nodes we check that this pfn does not already
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* reside in some other nodes.
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*/
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if (pfn_valid(pfn) && (early_pfn_to_nid(pfn) == node))
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register_page_bootmem_info_section(pfn);
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}
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}
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#endif /* CONFIG_HAVE_BOOTMEM_INFO_NODE */
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static int __meminit __add_section(int nid, unsigned long phys_start_pfn,
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struct vmem_altmap *altmap, bool want_memblock)
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{
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int ret;
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if (pfn_valid(phys_start_pfn))
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return -EEXIST;
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ret = sparse_add_one_section(NODE_DATA(nid), phys_start_pfn, altmap);
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if (ret < 0)
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return ret;
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if (!want_memblock)
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return 0;
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return hotplug_memory_register(nid, __pfn_to_section(phys_start_pfn));
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}
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/*
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* Reasonably generic function for adding memory. It is
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* expected that archs that support memory hotplug will
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* call this function after deciding the zone to which to
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* add the new pages.
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*/
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int __ref __add_pages(int nid, unsigned long phys_start_pfn,
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unsigned long nr_pages, struct vmem_altmap *altmap,
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bool want_memblock)
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{
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unsigned long i;
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int err = 0;
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int start_sec, end_sec;
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/* during initialize mem_map, align hot-added range to section */
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start_sec = pfn_to_section_nr(phys_start_pfn);
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end_sec = pfn_to_section_nr(phys_start_pfn + nr_pages - 1);
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if (altmap) {
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/*
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* Validate altmap is within bounds of the total request
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*/
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if (altmap->base_pfn != phys_start_pfn
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|| vmem_altmap_offset(altmap) > nr_pages) {
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pr_warn_once("memory add fail, invalid altmap\n");
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err = -EINVAL;
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goto out;
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}
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altmap->alloc = 0;
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}
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for (i = start_sec; i <= end_sec; i++) {
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err = __add_section(nid, section_nr_to_pfn(i), altmap,
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want_memblock);
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/*
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* EEXIST is finally dealt with by ioresource collision
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* check. see add_memory() => register_memory_resource()
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* Warning will be printed if there is collision.
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*/
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if (err && (err != -EEXIST))
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break;
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err = 0;
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cond_resched();
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}
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vmemmap_populate_print_last();
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out:
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return err;
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}
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#ifdef CONFIG_MEMORY_HOTREMOVE
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/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
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static unsigned long find_smallest_section_pfn(int nid, struct zone *zone,
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unsigned long start_pfn,
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unsigned long end_pfn)
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{
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struct mem_section *ms;
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for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SECTION) {
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ms = __pfn_to_section(start_pfn);
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if (unlikely(!valid_section(ms)))
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continue;
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if (unlikely(pfn_to_nid(start_pfn) != nid))
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continue;
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if (zone && zone != page_zone(pfn_to_page(start_pfn)))
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continue;
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return start_pfn;
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}
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return 0;
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}
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/* find the biggest valid pfn in the range [start_pfn, end_pfn). */
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static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
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unsigned long start_pfn,
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unsigned long end_pfn)
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{
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struct mem_section *ms;
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unsigned long pfn;
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/* pfn is the end pfn of a memory section. */
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pfn = end_pfn - 1;
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for (; pfn >= start_pfn; pfn -= PAGES_PER_SECTION) {
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ms = __pfn_to_section(pfn);
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if (unlikely(!valid_section(ms)))
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continue;
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if (unlikely(pfn_to_nid(pfn) != nid))
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continue;
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if (zone && zone != page_zone(pfn_to_page(pfn)))
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continue;
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return pfn;
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}
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return 0;
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}
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static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
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unsigned long end_pfn)
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{
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unsigned long zone_start_pfn = zone->zone_start_pfn;
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unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */
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unsigned long zone_end_pfn = z;
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unsigned long pfn;
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struct mem_section *ms;
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int nid = zone_to_nid(zone);
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zone_span_writelock(zone);
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if (zone_start_pfn == start_pfn) {
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/*
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* If the section is smallest section in the zone, it need
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* shrink zone->zone_start_pfn and zone->zone_spanned_pages.
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* In this case, we find second smallest valid mem_section
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* for shrinking zone.
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*/
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pfn = find_smallest_section_pfn(nid, zone, end_pfn,
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zone_end_pfn);
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if (pfn) {
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zone->zone_start_pfn = pfn;
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zone->spanned_pages = zone_end_pfn - pfn;
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}
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} else if (zone_end_pfn == end_pfn) {
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/*
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* If the section is biggest section in the zone, it need
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* shrink zone->spanned_pages.
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* In this case, we find second biggest valid mem_section for
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* shrinking zone.
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*/
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pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
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start_pfn);
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if (pfn)
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zone->spanned_pages = pfn - zone_start_pfn + 1;
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}
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/*
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* The section is not biggest or smallest mem_section in the zone, it
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* only creates a hole in the zone. So in this case, we need not
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* change the zone. But perhaps, the zone has only hole data. Thus
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* it check the zone has only hole or not.
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*/
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pfn = zone_start_pfn;
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for (; pfn < zone_end_pfn; pfn += PAGES_PER_SECTION) {
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ms = __pfn_to_section(pfn);
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if (unlikely(!valid_section(ms)))
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continue;
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if (page_zone(pfn_to_page(pfn)) != zone)
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continue;
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/* If the section is current section, it continues the loop */
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if (start_pfn == pfn)
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continue;
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/* If we find valid section, we have nothing to do */
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zone_span_writeunlock(zone);
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return;
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}
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/* The zone has no valid section */
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zone->zone_start_pfn = 0;
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zone->spanned_pages = 0;
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zone_span_writeunlock(zone);
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}
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static void shrink_pgdat_span(struct pglist_data *pgdat,
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unsigned long start_pfn, unsigned long end_pfn)
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{
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unsigned long pgdat_start_pfn = pgdat->node_start_pfn;
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unsigned long p = pgdat_end_pfn(pgdat); /* pgdat_end_pfn namespace clash */
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unsigned long pgdat_end_pfn = p;
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unsigned long pfn;
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struct mem_section *ms;
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int nid = pgdat->node_id;
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if (pgdat_start_pfn == start_pfn) {
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/*
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* If the section is smallest section in the pgdat, it need
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* shrink pgdat->node_start_pfn and pgdat->node_spanned_pages.
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* In this case, we find second smallest valid mem_section
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* for shrinking zone.
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*/
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pfn = find_smallest_section_pfn(nid, NULL, end_pfn,
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pgdat_end_pfn);
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if (pfn) {
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pgdat->node_start_pfn = pfn;
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pgdat->node_spanned_pages = pgdat_end_pfn - pfn;
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}
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} else if (pgdat_end_pfn == end_pfn) {
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/*
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* If the section is biggest section in the pgdat, it need
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* shrink pgdat->node_spanned_pages.
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* In this case, we find second biggest valid mem_section for
|
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* shrinking zone.
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*/
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pfn = find_biggest_section_pfn(nid, NULL, pgdat_start_pfn,
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start_pfn);
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if (pfn)
|
|
pgdat->node_spanned_pages = pfn - pgdat_start_pfn + 1;
|
|
}
|
|
|
|
/*
|
|
* If the section is not biggest or smallest mem_section in the pgdat,
|
|
* it only creates a hole in the pgdat. So in this case, we need not
|
|
* change the pgdat.
|
|
* But perhaps, the pgdat has only hole data. Thus it check the pgdat
|
|
* has only hole or not.
|
|
*/
|
|
pfn = pgdat_start_pfn;
|
|
for (; pfn < pgdat_end_pfn; pfn += PAGES_PER_SECTION) {
|
|
ms = __pfn_to_section(pfn);
|
|
|
|
if (unlikely(!valid_section(ms)))
|
|
continue;
|
|
|
|
if (pfn_to_nid(pfn) != nid)
|
|
continue;
|
|
|
|
/* If the section is current section, it continues the loop */
|
|
if (start_pfn == pfn)
|
|
continue;
|
|
|
|
/* If we find valid section, we have nothing to do */
|
|
return;
|
|
}
|
|
|
|
/* The pgdat has no valid section */
|
|
pgdat->node_start_pfn = 0;
|
|
pgdat->node_spanned_pages = 0;
|
|
}
|
|
|
|
static void __remove_zone(struct zone *zone, unsigned long start_pfn)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
int nr_pages = PAGES_PER_SECTION;
|
|
unsigned long flags;
|
|
|
|
pgdat_resize_lock(zone->zone_pgdat, &flags);
|
|
shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
|
|
shrink_pgdat_span(pgdat, start_pfn, start_pfn + nr_pages);
|
|
pgdat_resize_unlock(zone->zone_pgdat, &flags);
|
|
}
|
|
|
|
static int __remove_section(struct zone *zone, struct mem_section *ms,
|
|
unsigned long map_offset, struct vmem_altmap *altmap)
|
|
{
|
|
unsigned long start_pfn;
|
|
int scn_nr;
|
|
int ret = -EINVAL;
|
|
|
|
if (!valid_section(ms))
|
|
return ret;
|
|
|
|
ret = unregister_memory_section(ms);
|
|
if (ret)
|
|
return ret;
|
|
|
|
scn_nr = __section_nr(ms);
|
|
start_pfn = section_nr_to_pfn((unsigned long)scn_nr);
|
|
__remove_zone(zone, start_pfn);
|
|
|
|
sparse_remove_one_section(zone, ms, map_offset, altmap);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* __remove_pages() - remove sections of pages from a zone
|
|
* @zone: zone from which pages need to be removed
|
|
* @phys_start_pfn: starting pageframe (must be aligned to start of a section)
|
|
* @nr_pages: number of pages to remove (must be multiple of section size)
|
|
* @altmap: alternative device page map or %NULL if default memmap is used
|
|
*
|
|
* Generic helper function to remove section mappings and sysfs entries
|
|
* for the section of the memory we are removing. Caller needs to make
|
|
* sure that pages are marked reserved and zones are adjust properly by
|
|
* calling offline_pages().
|
|
*/
|
|
int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
|
|
unsigned long nr_pages, struct vmem_altmap *altmap)
|
|
{
|
|
unsigned long i;
|
|
unsigned long map_offset = 0;
|
|
int sections_to_remove, ret = 0;
|
|
|
|
/* In the ZONE_DEVICE case device driver owns the memory region */
|
|
if (is_dev_zone(zone)) {
|
|
if (altmap)
|
|
map_offset = vmem_altmap_offset(altmap);
|
|
} else {
|
|
resource_size_t start, size;
|
|
|
|
start = phys_start_pfn << PAGE_SHIFT;
|
|
size = nr_pages * PAGE_SIZE;
|
|
|
|
ret = release_mem_region_adjustable(&iomem_resource, start,
|
|
size);
|
|
if (ret) {
|
|
resource_size_t endres = start + size - 1;
|
|
|
|
pr_warn("Unable to release resource <%pa-%pa> (%d)\n",
|
|
&start, &endres, ret);
|
|
}
|
|
}
|
|
|
|
clear_zone_contiguous(zone);
|
|
|
|
/*
|
|
* We can only remove entire sections
|
|
*/
|
|
BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
|
|
BUG_ON(nr_pages % PAGES_PER_SECTION);
|
|
|
|
sections_to_remove = nr_pages / PAGES_PER_SECTION;
|
|
for (i = 0; i < sections_to_remove; i++) {
|
|
unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
|
|
|
|
ret = __remove_section(zone, __pfn_to_section(pfn), map_offset,
|
|
altmap);
|
|
map_offset = 0;
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
set_zone_contiguous(zone);
|
|
|
|
return ret;
|
|
}
|
|
#endif /* CONFIG_MEMORY_HOTREMOVE */
|
|
|
|
int set_online_page_callback(online_page_callback_t callback)
|
|
{
|
|
int rc = -EINVAL;
|
|
|
|
get_online_mems();
|
|
mutex_lock(&online_page_callback_lock);
|
|
|
|
if (online_page_callback == generic_online_page) {
|
|
online_page_callback = callback;
|
|
rc = 0;
|
|
}
|
|
|
|
mutex_unlock(&online_page_callback_lock);
|
|
put_online_mems();
|
|
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(set_online_page_callback);
|
|
|
|
int restore_online_page_callback(online_page_callback_t callback)
|
|
{
|
|
int rc = -EINVAL;
|
|
|
|
get_online_mems();
|
|
mutex_lock(&online_page_callback_lock);
|
|
|
|
if (online_page_callback == callback) {
|
|
online_page_callback = generic_online_page;
|
|
rc = 0;
|
|
}
|
|
|
|
mutex_unlock(&online_page_callback_lock);
|
|
put_online_mems();
|
|
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(restore_online_page_callback);
|
|
|
|
void __online_page_set_limits(struct page *page)
|
|
{
|
|
}
|
|
EXPORT_SYMBOL_GPL(__online_page_set_limits);
|
|
|
|
void __online_page_increment_counters(struct page *page)
|
|
{
|
|
adjust_managed_page_count(page, 1);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__online_page_increment_counters);
|
|
|
|
void __online_page_free(struct page *page)
|
|
{
|
|
__free_reserved_page(page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__online_page_free);
|
|
|
|
static void generic_online_page(struct page *page)
|
|
{
|
|
__online_page_set_limits(page);
|
|
__online_page_increment_counters(page);
|
|
__online_page_free(page);
|
|
}
|
|
|
|
static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
|
|
void *arg)
|
|
{
|
|
unsigned long i;
|
|
unsigned long onlined_pages = *(unsigned long *)arg;
|
|
struct page *page;
|
|
|
|
if (PageReserved(pfn_to_page(start_pfn)))
|
|
for (i = 0; i < nr_pages; i++) {
|
|
page = pfn_to_page(start_pfn + i);
|
|
(*online_page_callback)(page);
|
|
onlined_pages++;
|
|
}
|
|
|
|
online_mem_sections(start_pfn, start_pfn + nr_pages);
|
|
|
|
*(unsigned long *)arg = onlined_pages;
|
|
return 0;
|
|
}
|
|
|
|
/* check which state of node_states will be changed when online memory */
|
|
static void node_states_check_changes_online(unsigned long nr_pages,
|
|
struct zone *zone, struct memory_notify *arg)
|
|
{
|
|
int nid = zone_to_nid(zone);
|
|
|
|
arg->status_change_nid = -1;
|
|
arg->status_change_nid_normal = -1;
|
|
arg->status_change_nid_high = -1;
|
|
|
|
if (!node_state(nid, N_MEMORY))
|
|
arg->status_change_nid = nid;
|
|
if (zone_idx(zone) <= ZONE_NORMAL && !node_state(nid, N_NORMAL_MEMORY))
|
|
arg->status_change_nid_normal = nid;
|
|
#ifdef CONFIG_HIGHMEM
|
|
if (zone_idx(zone) <= N_HIGH_MEMORY && !node_state(nid, N_HIGH_MEMORY))
|
|
arg->status_change_nid_high = nid;
|
|
#endif
|
|
}
|
|
|
|
static void node_states_set_node(int node, struct memory_notify *arg)
|
|
{
|
|
if (arg->status_change_nid_normal >= 0)
|
|
node_set_state(node, N_NORMAL_MEMORY);
|
|
|
|
if (arg->status_change_nid_high >= 0)
|
|
node_set_state(node, N_HIGH_MEMORY);
|
|
|
|
if (arg->status_change_nid >= 0)
|
|
node_set_state(node, N_MEMORY);
|
|
}
|
|
|
|
static void __meminit resize_zone_range(struct zone *zone, unsigned long start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
unsigned long old_end_pfn = zone_end_pfn(zone);
|
|
|
|
if (zone_is_empty(zone) || start_pfn < zone->zone_start_pfn)
|
|
zone->zone_start_pfn = start_pfn;
|
|
|
|
zone->spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - zone->zone_start_pfn;
|
|
}
|
|
|
|
static void __meminit resize_pgdat_range(struct pglist_data *pgdat, unsigned long start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
unsigned long old_end_pfn = pgdat_end_pfn(pgdat);
|
|
|
|
if (!pgdat->node_spanned_pages || start_pfn < pgdat->node_start_pfn)
|
|
pgdat->node_start_pfn = start_pfn;
|
|
|
|
pgdat->node_spanned_pages = max(start_pfn + nr_pages, old_end_pfn) - pgdat->node_start_pfn;
|
|
}
|
|
|
|
void __ref move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
|
|
unsigned long nr_pages, struct vmem_altmap *altmap)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
int nid = pgdat->node_id;
|
|
unsigned long flags;
|
|
|
|
if (zone_is_empty(zone))
|
|
init_currently_empty_zone(zone, start_pfn, nr_pages);
|
|
|
|
clear_zone_contiguous(zone);
|
|
|
|
/* TODO Huh pgdat is irqsave while zone is not. It used to be like that before */
|
|
pgdat_resize_lock(pgdat, &flags);
|
|
zone_span_writelock(zone);
|
|
resize_zone_range(zone, start_pfn, nr_pages);
|
|
zone_span_writeunlock(zone);
|
|
resize_pgdat_range(pgdat, start_pfn, nr_pages);
|
|
pgdat_resize_unlock(pgdat, &flags);
|
|
|
|
/*
|
|
* TODO now we have a visible range of pages which are not associated
|
|
* with their zone properly. Not nice but set_pfnblock_flags_mask
|
|
* expects the zone spans the pfn range. All the pages in the range
|
|
* are reserved so nobody should be touching them so we should be safe
|
|
*/
|
|
memmap_init_zone(nr_pages, nid, zone_idx(zone), start_pfn,
|
|
MEMMAP_HOTPLUG, altmap);
|
|
|
|
set_zone_contiguous(zone);
|
|
}
|
|
|
|
/*
|
|
* Returns a default kernel memory zone for the given pfn range.
|
|
* If no kernel zone covers this pfn range it will automatically go
|
|
* to the ZONE_NORMAL.
|
|
*/
|
|
static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
struct pglist_data *pgdat = NODE_DATA(nid);
|
|
int zid;
|
|
|
|
for (zid = 0; zid <= ZONE_NORMAL; zid++) {
|
|
struct zone *zone = &pgdat->node_zones[zid];
|
|
|
|
if (zone_intersects(zone, start_pfn, nr_pages))
|
|
return zone;
|
|
}
|
|
|
|
return &pgdat->node_zones[ZONE_NORMAL];
|
|
}
|
|
|
|
static inline struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
struct zone *kernel_zone = default_kernel_zone_for_pfn(nid, start_pfn,
|
|
nr_pages);
|
|
struct zone *movable_zone = &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
|
|
bool in_kernel = zone_intersects(kernel_zone, start_pfn, nr_pages);
|
|
bool in_movable = zone_intersects(movable_zone, start_pfn, nr_pages);
|
|
|
|
/*
|
|
* We inherit the existing zone in a simple case where zones do not
|
|
* overlap in the given range
|
|
*/
|
|
if (in_kernel ^ in_movable)
|
|
return (in_kernel) ? kernel_zone : movable_zone;
|
|
|
|
/*
|
|
* If the range doesn't belong to any zone or two zones overlap in the
|
|
* given range then we use movable zone only if movable_node is
|
|
* enabled because we always online to a kernel zone by default.
|
|
*/
|
|
return movable_node_enabled ? movable_zone : kernel_zone;
|
|
}
|
|
|
|
struct zone * zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
|
|
unsigned long nr_pages)
|
|
{
|
|
if (online_type == MMOP_ONLINE_KERNEL)
|
|
return default_kernel_zone_for_pfn(nid, start_pfn, nr_pages);
|
|
|
|
if (online_type == MMOP_ONLINE_MOVABLE)
|
|
return &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
|
|
|
|
return default_zone_for_pfn(nid, start_pfn, nr_pages);
|
|
}
|
|
|
|
/*
|
|
* Associates the given pfn range with the given node and the zone appropriate
|
|
* for the given online type.
|
|
*/
|
|
static struct zone * __meminit move_pfn_range(int online_type, int nid,
|
|
unsigned long start_pfn, unsigned long nr_pages)
|
|
{
|
|
struct zone *zone;
|
|
|
|
zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
|
|
move_pfn_range_to_zone(zone, start_pfn, nr_pages, NULL);
|
|
return zone;
|
|
}
|
|
|
|
/* Must be protected by mem_hotplug_begin() or a device_lock */
|
|
int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
|
|
{
|
|
unsigned long flags;
|
|
unsigned long onlined_pages = 0;
|
|
struct zone *zone;
|
|
int need_zonelists_rebuild = 0;
|
|
int nid;
|
|
int ret;
|
|
struct memory_notify arg;
|
|
struct memory_block *mem;
|
|
|
|
/*
|
|
* We can't use pfn_to_nid() because nid might be stored in struct page
|
|
* which is not yet initialized. Instead, we find nid from memory block.
|
|
*/
|
|
mem = find_memory_block(__pfn_to_section(pfn));
|
|
nid = mem->nid;
|
|
|
|
/* associate pfn range with the zone */
|
|
zone = move_pfn_range(online_type, nid, pfn, nr_pages);
|
|
|
|
arg.start_pfn = pfn;
|
|
arg.nr_pages = nr_pages;
|
|
node_states_check_changes_online(nr_pages, zone, &arg);
|
|
|
|
ret = memory_notify(MEM_GOING_ONLINE, &arg);
|
|
ret = notifier_to_errno(ret);
|
|
if (ret)
|
|
goto failed_addition;
|
|
|
|
/*
|
|
* If this zone is not populated, then it is not in zonelist.
|
|
* This means the page allocator ignores this zone.
|
|
* So, zonelist must be updated after online.
|
|
*/
|
|
if (!populated_zone(zone)) {
|
|
need_zonelists_rebuild = 1;
|
|
setup_zone_pageset(zone);
|
|
}
|
|
|
|
ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
|
|
online_pages_range);
|
|
if (ret) {
|
|
if (need_zonelists_rebuild)
|
|
zone_pcp_reset(zone);
|
|
goto failed_addition;
|
|
}
|
|
|
|
zone->present_pages += onlined_pages;
|
|
|
|
pgdat_resize_lock(zone->zone_pgdat, &flags);
|
|
zone->zone_pgdat->node_present_pages += onlined_pages;
|
|
pgdat_resize_unlock(zone->zone_pgdat, &flags);
|
|
|
|
if (onlined_pages) {
|
|
node_states_set_node(nid, &arg);
|
|
if (need_zonelists_rebuild)
|
|
build_all_zonelists(NULL);
|
|
else
|
|
zone_pcp_update(zone);
|
|
}
|
|
|
|
init_per_zone_wmark_min();
|
|
|
|
if (onlined_pages) {
|
|
kswapd_run(nid);
|
|
kcompactd_run(nid);
|
|
}
|
|
|
|
vm_total_pages = nr_free_pagecache_pages();
|
|
|
|
writeback_set_ratelimit();
|
|
|
|
if (onlined_pages)
|
|
memory_notify(MEM_ONLINE, &arg);
|
|
return 0;
|
|
|
|
failed_addition:
|
|
pr_debug("online_pages [mem %#010llx-%#010llx] failed\n",
|
|
(unsigned long long) pfn << PAGE_SHIFT,
|
|
(((unsigned long long) pfn + nr_pages) << PAGE_SHIFT) - 1);
|
|
memory_notify(MEM_CANCEL_ONLINE, &arg);
|
|
return ret;
|
|
}
|
|
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
|
|
|
|
static void reset_node_present_pages(pg_data_t *pgdat)
|
|
{
|
|
struct zone *z;
|
|
|
|
for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++)
|
|
z->present_pages = 0;
|
|
|
|
pgdat->node_present_pages = 0;
|
|
}
|
|
|
|
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
|
|
static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
unsigned long start_pfn = PFN_DOWN(start);
|
|
|
|
pgdat = NODE_DATA(nid);
|
|
if (!pgdat) {
|
|
pgdat = arch_alloc_nodedata(nid);
|
|
if (!pgdat)
|
|
return NULL;
|
|
|
|
arch_refresh_nodedata(nid, pgdat);
|
|
} else {
|
|
/*
|
|
* Reset the nr_zones, order and classzone_idx before reuse.
|
|
* Note that kswapd will init kswapd_classzone_idx properly
|
|
* when it starts in the near future.
|
|
*/
|
|
pgdat->nr_zones = 0;
|
|
pgdat->kswapd_order = 0;
|
|
pgdat->kswapd_classzone_idx = 0;
|
|
}
|
|
|
|
/* we can use NODE_DATA(nid) from here */
|
|
|
|
pgdat->node_id = nid;
|
|
pgdat->node_start_pfn = start_pfn;
|
|
|
|
/* init node's zones as empty zones, we don't have any present pages.*/
|
|
free_area_init_core_hotplug(nid);
|
|
pgdat->per_cpu_nodestats = alloc_percpu(struct per_cpu_nodestat);
|
|
|
|
/*
|
|
* The node we allocated has no zone fallback lists. For avoiding
|
|
* to access not-initialized zonelist, build here.
|
|
*/
|
|
build_all_zonelists(pgdat);
|
|
|
|
/*
|
|
* When memory is hot-added, all the memory is in offline state. So
|
|
* clear all zones' present_pages because they will be updated in
|
|
* online_pages() and offline_pages().
|
|
*/
|
|
reset_node_managed_pages(pgdat);
|
|
reset_node_present_pages(pgdat);
|
|
|
|
return pgdat;
|
|
}
|
|
|
|
static void rollback_node_hotadd(int nid)
|
|
{
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
|
|
arch_refresh_nodedata(nid, NULL);
|
|
free_percpu(pgdat->per_cpu_nodestats);
|
|
arch_free_nodedata(pgdat);
|
|
return;
|
|
}
|
|
|
|
|
|
/**
|
|
* try_online_node - online a node if offlined
|
|
* @nid: the node ID
|
|
* @start: start addr of the node
|
|
* @set_node_online: Whether we want to online the node
|
|
* called by cpu_up() to online a node without onlined memory.
|
|
*
|
|
* Returns:
|
|
* 1 -> a new node has been allocated
|
|
* 0 -> the node is already online
|
|
* -ENOMEM -> the node could not be allocated
|
|
*/
|
|
static int __try_online_node(int nid, u64 start, bool set_node_online)
|
|
{
|
|
pg_data_t *pgdat;
|
|
int ret = 1;
|
|
|
|
if (node_online(nid))
|
|
return 0;
|
|
|
|
pgdat = hotadd_new_pgdat(nid, start);
|
|
if (!pgdat) {
|
|
pr_err("Cannot online node %d due to NULL pgdat\n", nid);
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
if (set_node_online) {
|
|
node_set_online(nid);
|
|
ret = register_one_node(nid);
|
|
BUG_ON(ret);
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Users of this function always want to online/register the node
|
|
*/
|
|
int try_online_node(int nid)
|
|
{
|
|
int ret;
|
|
|
|
mem_hotplug_begin();
|
|
ret = __try_online_node(nid, 0, true);
|
|
mem_hotplug_done();
|
|
return ret;
|
|
}
|
|
|
|
static int check_hotplug_memory_range(u64 start, u64 size)
|
|
{
|
|
unsigned long block_sz = memory_block_size_bytes();
|
|
u64 block_nr_pages = block_sz >> PAGE_SHIFT;
|
|
u64 nr_pages = size >> PAGE_SHIFT;
|
|
u64 start_pfn = PFN_DOWN(start);
|
|
|
|
/* memory range must be block size aligned */
|
|
if (!nr_pages || !IS_ALIGNED(start_pfn, block_nr_pages) ||
|
|
!IS_ALIGNED(nr_pages, block_nr_pages)) {
|
|
pr_err("Block size [%#lx] unaligned hotplug range: start %#llx, size %#llx",
|
|
block_sz, start, size);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int online_memory_block(struct memory_block *mem, void *arg)
|
|
{
|
|
return device_online(&mem->dev);
|
|
}
|
|
|
|
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
|
|
int __ref add_memory_resource(int nid, struct resource *res, bool online)
|
|
{
|
|
u64 start, size;
|
|
bool new_node = false;
|
|
int ret;
|
|
|
|
start = res->start;
|
|
size = resource_size(res);
|
|
|
|
ret = check_hotplug_memory_range(start, size);
|
|
if (ret)
|
|
return ret;
|
|
|
|
mem_hotplug_begin();
|
|
|
|
/*
|
|
* Add new range to memblock so that when hotadd_new_pgdat() is called
|
|
* to allocate new pgdat, get_pfn_range_for_nid() will be able to find
|
|
* this new range and calculate total pages correctly. The range will
|
|
* be removed at hot-remove time.
|
|
*/
|
|
memblock_add_node(start, size, nid);
|
|
|
|
ret = __try_online_node(nid, start, false);
|
|
if (ret < 0)
|
|
goto error;
|
|
new_node = ret;
|
|
|
|
/* call arch's memory hotadd */
|
|
ret = arch_add_memory(nid, start, size, NULL, true);
|
|
if (ret < 0)
|
|
goto error;
|
|
|
|
if (new_node) {
|
|
/* If sysfs file of new node can't be created, cpu on the node
|
|
* can't be hot-added. There is no rollback way now.
|
|
* So, check by BUG_ON() to catch it reluctantly..
|
|
* We online node here. We can't roll back from here.
|
|
*/
|
|
node_set_online(nid);
|
|
ret = __register_one_node(nid);
|
|
BUG_ON(ret);
|
|
}
|
|
|
|
/* link memory sections under this node.*/
|
|
ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1));
|
|
BUG_ON(ret);
|
|
|
|
/* create new memmap entry */
|
|
firmware_map_add_hotplug(start, start + size, "System RAM");
|
|
|
|
/* online pages if requested */
|
|
if (online)
|
|
walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1),
|
|
NULL, online_memory_block);
|
|
|
|
goto out;
|
|
|
|
error:
|
|
/* rollback pgdat allocation and others */
|
|
if (new_node)
|
|
rollback_node_hotadd(nid);
|
|
memblock_remove(start, size);
|
|
|
|
out:
|
|
mem_hotplug_done();
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(add_memory_resource);
|
|
|
|
int __ref add_memory(int nid, u64 start, u64 size)
|
|
{
|
|
struct resource *res;
|
|
int ret;
|
|
|
|
res = register_memory_resource(start, size);
|
|
if (IS_ERR(res))
|
|
return PTR_ERR(res);
|
|
|
|
ret = add_memory_resource(nid, res, memhp_auto_online);
|
|
if (ret < 0)
|
|
release_memory_resource(res);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(add_memory);
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
/*
|
|
* A free page on the buddy free lists (not the per-cpu lists) has PageBuddy
|
|
* set and the size of the free page is given by page_order(). Using this,
|
|
* the function determines if the pageblock contains only free pages.
|
|
* Due to buddy contraints, a free page at least the size of a pageblock will
|
|
* be located at the start of the pageblock
|
|
*/
|
|
static inline int pageblock_free(struct page *page)
|
|
{
|
|
return PageBuddy(page) && page_order(page) >= pageblock_order;
|
|
}
|
|
|
|
/* Return the start of the next active pageblock after a given page */
|
|
static struct page *next_active_pageblock(struct page *page)
|
|
{
|
|
/* Ensure the starting page is pageblock-aligned */
|
|
BUG_ON(page_to_pfn(page) & (pageblock_nr_pages - 1));
|
|
|
|
/* If the entire pageblock is free, move to the end of free page */
|
|
if (pageblock_free(page)) {
|
|
int order;
|
|
/* be careful. we don't have locks, page_order can be changed.*/
|
|
order = page_order(page);
|
|
if ((order < MAX_ORDER) && (order >= pageblock_order))
|
|
return page + (1 << order);
|
|
}
|
|
|
|
return page + pageblock_nr_pages;
|
|
}
|
|
|
|
static bool is_pageblock_removable_nolock(struct page *page)
|
|
{
|
|
struct zone *zone;
|
|
unsigned long pfn;
|
|
|
|
/*
|
|
* We have to be careful here because we are iterating over memory
|
|
* sections which are not zone aware so we might end up outside of
|
|
* the zone but still within the section.
|
|
* We have to take care about the node as well. If the node is offline
|
|
* its NODE_DATA will be NULL - see page_zone.
|
|
*/
|
|
if (!node_online(page_to_nid(page)))
|
|
return false;
|
|
|
|
zone = page_zone(page);
|
|
pfn = page_to_pfn(page);
|
|
if (!zone_spans_pfn(zone, pfn))
|
|
return false;
|
|
|
|
return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, true);
|
|
}
|
|
|
|
/* Checks if this range of memory is likely to be hot-removable. */
|
|
bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
|
|
{
|
|
struct page *page = pfn_to_page(start_pfn);
|
|
struct page *end_page = page + nr_pages;
|
|
|
|
/* Check the starting page of each pageblock within the range */
|
|
for (; page < end_page; page = next_active_pageblock(page)) {
|
|
if (!is_pageblock_removable_nolock(page))
|
|
return false;
|
|
cond_resched();
|
|
}
|
|
|
|
/* All pageblocks in the memory block are likely to be hot-removable */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Confirm all pages in a range [start, end) belong to the same zone.
|
|
* When true, return its valid [start, end).
|
|
*/
|
|
int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn,
|
|
unsigned long *valid_start, unsigned long *valid_end)
|
|
{
|
|
unsigned long pfn, sec_end_pfn;
|
|
unsigned long start, end;
|
|
struct zone *zone = NULL;
|
|
struct page *page;
|
|
int i;
|
|
for (pfn = start_pfn, sec_end_pfn = SECTION_ALIGN_UP(start_pfn + 1);
|
|
pfn < end_pfn;
|
|
pfn = sec_end_pfn, sec_end_pfn += PAGES_PER_SECTION) {
|
|
/* Make sure the memory section is present first */
|
|
if (!present_section_nr(pfn_to_section_nr(pfn)))
|
|
continue;
|
|
for (; pfn < sec_end_pfn && pfn < end_pfn;
|
|
pfn += MAX_ORDER_NR_PAGES) {
|
|
i = 0;
|
|
/* This is just a CONFIG_HOLES_IN_ZONE check.*/
|
|
while ((i < MAX_ORDER_NR_PAGES) &&
|
|
!pfn_valid_within(pfn + i))
|
|
i++;
|
|
if (i == MAX_ORDER_NR_PAGES || pfn + i >= end_pfn)
|
|
continue;
|
|
page = pfn_to_page(pfn + i);
|
|
if (zone && page_zone(page) != zone)
|
|
return 0;
|
|
if (!zone)
|
|
start = pfn + i;
|
|
zone = page_zone(page);
|
|
end = pfn + MAX_ORDER_NR_PAGES;
|
|
}
|
|
}
|
|
|
|
if (zone) {
|
|
*valid_start = start;
|
|
*valid_end = min(end, end_pfn);
|
|
return 1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Scan pfn range [start,end) to find movable/migratable pages (LRU pages,
|
|
* non-lru movable pages and hugepages). We scan pfn because it's much
|
|
* easier than scanning over linked list. This function returns the pfn
|
|
* of the first found movable page if it's found, otherwise 0.
|
|
*/
|
|
static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long pfn;
|
|
struct page *page;
|
|
for (pfn = start; pfn < end; pfn++) {
|
|
if (pfn_valid(pfn)) {
|
|
page = pfn_to_page(pfn);
|
|
if (PageLRU(page))
|
|
return pfn;
|
|
if (__PageMovable(page))
|
|
return pfn;
|
|
if (PageHuge(page)) {
|
|
if (hugepage_migration_supported(page_hstate(page)) &&
|
|
page_huge_active(page))
|
|
return pfn;
|
|
else
|
|
pfn = round_up(pfn + 1,
|
|
1 << compound_order(page)) - 1;
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct page *new_node_page(struct page *page, unsigned long private)
|
|
{
|
|
int nid = page_to_nid(page);
|
|
nodemask_t nmask = node_states[N_MEMORY];
|
|
|
|
/*
|
|
* try to allocate from a different node but reuse this node if there
|
|
* are no other online nodes to be used (e.g. we are offlining a part
|
|
* of the only existing node)
|
|
*/
|
|
node_clear(nid, nmask);
|
|
if (nodes_empty(nmask))
|
|
node_set(nid, nmask);
|
|
|
|
return new_page_nodemask(page, nid, &nmask);
|
|
}
|
|
|
|
#define NR_OFFLINE_AT_ONCE_PAGES (256)
|
|
static int
|
|
do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
unsigned long pfn;
|
|
struct page *page;
|
|
int move_pages = NR_OFFLINE_AT_ONCE_PAGES;
|
|
int not_managed = 0;
|
|
int ret = 0;
|
|
LIST_HEAD(source);
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) {
|
|
if (!pfn_valid(pfn))
|
|
continue;
|
|
page = pfn_to_page(pfn);
|
|
|
|
if (PageHuge(page)) {
|
|
struct page *head = compound_head(page);
|
|
pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1;
|
|
if (compound_order(head) > PFN_SECTION_SHIFT) {
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
if (isolate_huge_page(page, &source))
|
|
move_pages -= 1 << compound_order(head);
|
|
continue;
|
|
} else if (PageTransHuge(page))
|
|
pfn = page_to_pfn(compound_head(page))
|
|
+ hpage_nr_pages(page) - 1;
|
|
|
|
if (!get_page_unless_zero(page))
|
|
continue;
|
|
/*
|
|
* We can skip free pages. And we can deal with pages on
|
|
* LRU and non-lru movable pages.
|
|
*/
|
|
if (PageLRU(page))
|
|
ret = isolate_lru_page(page);
|
|
else
|
|
ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
|
|
if (!ret) { /* Success */
|
|
put_page(page);
|
|
list_add_tail(&page->lru, &source);
|
|
move_pages--;
|
|
if (!__PageMovable(page))
|
|
inc_node_page_state(page, NR_ISOLATED_ANON +
|
|
page_is_file_cache(page));
|
|
|
|
} else {
|
|
#ifdef CONFIG_DEBUG_VM
|
|
pr_alert("failed to isolate pfn %lx\n", pfn);
|
|
dump_page(page, "isolation failed");
|
|
#endif
|
|
put_page(page);
|
|
/* Because we don't have big zone->lock. we should
|
|
check this again here. */
|
|
if (page_count(page)) {
|
|
not_managed++;
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (!list_empty(&source)) {
|
|
if (not_managed) {
|
|
putback_movable_pages(&source);
|
|
goto out;
|
|
}
|
|
|
|
/* Allocate a new page from the nearest neighbor node */
|
|
ret = migrate_pages(&source, new_node_page, NULL, 0,
|
|
MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
|
|
if (ret)
|
|
putback_movable_pages(&source);
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* remove from free_area[] and mark all as Reserved.
|
|
*/
|
|
static int
|
|
offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
|
|
void *data)
|
|
{
|
|
__offline_isolated_pages(start, start + nr_pages);
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
walk_system_ram_range(start_pfn, end_pfn - start_pfn, NULL,
|
|
offline_isolated_pages_cb);
|
|
}
|
|
|
|
/*
|
|
* Check all pages in range, recoreded as memory resource, are isolated.
|
|
*/
|
|
static int
|
|
check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
|
|
void *data)
|
|
{
|
|
int ret;
|
|
long offlined = *(long *)data;
|
|
ret = test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
|
|
offlined = nr_pages;
|
|
if (!ret)
|
|
*(long *)data += offlined;
|
|
return ret;
|
|
}
|
|
|
|
static long
|
|
check_pages_isolated(unsigned long start_pfn, unsigned long end_pfn)
|
|
{
|
|
long offlined = 0;
|
|
int ret;
|
|
|
|
ret = walk_system_ram_range(start_pfn, end_pfn - start_pfn, &offlined,
|
|
check_pages_isolated_cb);
|
|
if (ret < 0)
|
|
offlined = (long)ret;
|
|
return offlined;
|
|
}
|
|
|
|
static int __init cmdline_parse_movable_node(char *p)
|
|
{
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
|
movable_node_enabled = true;
|
|
#else
|
|
pr_warn("movable_node parameter depends on CONFIG_HAVE_MEMBLOCK_NODE_MAP to work properly\n");
|
|
#endif
|
|
return 0;
|
|
}
|
|
early_param("movable_node", cmdline_parse_movable_node);
|
|
|
|
/* check which state of node_states will be changed when offline memory */
|
|
static void node_states_check_changes_offline(unsigned long nr_pages,
|
|
struct zone *zone, struct memory_notify *arg)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
unsigned long present_pages = 0;
|
|
enum zone_type zt;
|
|
|
|
arg->status_change_nid = -1;
|
|
arg->status_change_nid_normal = -1;
|
|
arg->status_change_nid_high = -1;
|
|
|
|
/*
|
|
* Check whether node_states[N_NORMAL_MEMORY] will be changed.
|
|
* If the memory to be offline is within the range
|
|
* [0..ZONE_NORMAL], and it is the last present memory there,
|
|
* the zones in that range will become empty after the offlining,
|
|
* thus we can determine that we need to clear the node from
|
|
* node_states[N_NORMAL_MEMORY].
|
|
*/
|
|
for (zt = 0; zt <= ZONE_NORMAL; zt++)
|
|
present_pages += pgdat->node_zones[zt].present_pages;
|
|
if (zone_idx(zone) <= ZONE_NORMAL && nr_pages >= present_pages)
|
|
arg->status_change_nid_normal = zone_to_nid(zone);
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
/*
|
|
* node_states[N_HIGH_MEMORY] contains nodes which
|
|
* have normal memory or high memory.
|
|
* Here we add the present_pages belonging to ZONE_HIGHMEM.
|
|
* If the zone is within the range of [0..ZONE_HIGHMEM), and
|
|
* we determine that the zones in that range become empty,
|
|
* we need to clear the node for N_HIGH_MEMORY.
|
|
*/
|
|
present_pages += pgdat->node_zones[ZONE_HIGHMEM].present_pages;
|
|
if (zone_idx(zone) <= ZONE_HIGHMEM && nr_pages >= present_pages)
|
|
arg->status_change_nid_high = zone_to_nid(zone);
|
|
#endif
|
|
|
|
/*
|
|
* We have accounted the pages from [0..ZONE_NORMAL), and
|
|
* in case of CONFIG_HIGHMEM the pages from ZONE_HIGHMEM
|
|
* as well.
|
|
* Here we count the possible pages from ZONE_MOVABLE.
|
|
* If after having accounted all the pages, we see that the nr_pages
|
|
* to be offlined is over or equal to the accounted pages,
|
|
* we know that the node will become empty, and so, we can clear
|
|
* it for N_MEMORY as well.
|
|
*/
|
|
present_pages += pgdat->node_zones[ZONE_MOVABLE].present_pages;
|
|
|
|
if (nr_pages >= present_pages)
|
|
arg->status_change_nid = zone_to_nid(zone);
|
|
}
|
|
|
|
static void node_states_clear_node(int node, struct memory_notify *arg)
|
|
{
|
|
if (arg->status_change_nid_normal >= 0)
|
|
node_clear_state(node, N_NORMAL_MEMORY);
|
|
|
|
if (arg->status_change_nid_high >= 0)
|
|
node_clear_state(node, N_HIGH_MEMORY);
|
|
|
|
if (arg->status_change_nid >= 0)
|
|
node_clear_state(node, N_MEMORY);
|
|
}
|
|
|
|
static int __ref __offline_pages(unsigned long start_pfn,
|
|
unsigned long end_pfn)
|
|
{
|
|
unsigned long pfn, nr_pages;
|
|
long offlined_pages;
|
|
int ret, node;
|
|
unsigned long flags;
|
|
unsigned long valid_start, valid_end;
|
|
struct zone *zone;
|
|
struct memory_notify arg;
|
|
|
|
/* at least, alignment against pageblock is necessary */
|
|
if (!IS_ALIGNED(start_pfn, pageblock_nr_pages))
|
|
return -EINVAL;
|
|
if (!IS_ALIGNED(end_pfn, pageblock_nr_pages))
|
|
return -EINVAL;
|
|
/* This makes hotplug much easier...and readable.
|
|
we assume this for now. .*/
|
|
if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start, &valid_end))
|
|
return -EINVAL;
|
|
|
|
zone = page_zone(pfn_to_page(valid_start));
|
|
node = zone_to_nid(zone);
|
|
nr_pages = end_pfn - start_pfn;
|
|
|
|
/* set above range as isolated */
|
|
ret = start_isolate_page_range(start_pfn, end_pfn,
|
|
MIGRATE_MOVABLE, true);
|
|
if (ret)
|
|
return ret;
|
|
|
|
arg.start_pfn = start_pfn;
|
|
arg.nr_pages = nr_pages;
|
|
node_states_check_changes_offline(nr_pages, zone, &arg);
|
|
|
|
ret = memory_notify(MEM_GOING_OFFLINE, &arg);
|
|
ret = notifier_to_errno(ret);
|
|
if (ret)
|
|
goto failed_removal;
|
|
|
|
pfn = start_pfn;
|
|
repeat:
|
|
/* start memory hot removal */
|
|
ret = -EINTR;
|
|
if (signal_pending(current))
|
|
goto failed_removal;
|
|
|
|
cond_resched();
|
|
lru_add_drain_all();
|
|
drain_all_pages(zone);
|
|
|
|
pfn = scan_movable_pages(start_pfn, end_pfn);
|
|
if (pfn) { /* We have movable pages */
|
|
ret = do_migrate_range(pfn, end_pfn);
|
|
goto repeat;
|
|
}
|
|
|
|
/*
|
|
* dissolve free hugepages in the memory block before doing offlining
|
|
* actually in order to make hugetlbfs's object counting consistent.
|
|
*/
|
|
ret = dissolve_free_huge_pages(start_pfn, end_pfn);
|
|
if (ret)
|
|
goto failed_removal;
|
|
/* check again */
|
|
offlined_pages = check_pages_isolated(start_pfn, end_pfn);
|
|
if (offlined_pages < 0)
|
|
goto repeat;
|
|
pr_info("Offlined Pages %ld\n", offlined_pages);
|
|
/* Ok, all of our target is isolated.
|
|
We cannot do rollback at this point. */
|
|
offline_isolated_pages(start_pfn, end_pfn);
|
|
/* reset pagetype flags and makes migrate type to be MOVABLE */
|
|
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
|
|
/* removal success */
|
|
adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
|
|
zone->present_pages -= offlined_pages;
|
|
|
|
pgdat_resize_lock(zone->zone_pgdat, &flags);
|
|
zone->zone_pgdat->node_present_pages -= offlined_pages;
|
|
pgdat_resize_unlock(zone->zone_pgdat, &flags);
|
|
|
|
init_per_zone_wmark_min();
|
|
|
|
if (!populated_zone(zone)) {
|
|
zone_pcp_reset(zone);
|
|
build_all_zonelists(NULL);
|
|
} else
|
|
zone_pcp_update(zone);
|
|
|
|
node_states_clear_node(node, &arg);
|
|
if (arg.status_change_nid >= 0) {
|
|
kswapd_stop(node);
|
|
kcompactd_stop(node);
|
|
}
|
|
|
|
vm_total_pages = nr_free_pagecache_pages();
|
|
writeback_set_ratelimit();
|
|
|
|
memory_notify(MEM_OFFLINE, &arg);
|
|
return 0;
|
|
|
|
failed_removal:
|
|
pr_debug("memory offlining [mem %#010llx-%#010llx] failed\n",
|
|
(unsigned long long) start_pfn << PAGE_SHIFT,
|
|
((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
|
|
memory_notify(MEM_CANCEL_OFFLINE, &arg);
|
|
/* pushback to free area */
|
|
undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
|
|
return ret;
|
|
}
|
|
|
|
/* Must be protected by mem_hotplug_begin() or a device_lock */
|
|
int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
|
|
{
|
|
return __offline_pages(start_pfn, start_pfn + nr_pages);
|
|
}
|
|
#endif /* CONFIG_MEMORY_HOTREMOVE */
|
|
|
|
/**
|
|
* walk_memory_range - walks through all mem sections in [start_pfn, end_pfn)
|
|
* @start_pfn: start pfn of the memory range
|
|
* @end_pfn: end pfn of the memory range
|
|
* @arg: argument passed to func
|
|
* @func: callback for each memory section walked
|
|
*
|
|
* This function walks through all present mem sections in range
|
|
* [start_pfn, end_pfn) and call func on each mem section.
|
|
*
|
|
* Returns the return value of func.
|
|
*/
|
|
int walk_memory_range(unsigned long start_pfn, unsigned long end_pfn,
|
|
void *arg, int (*func)(struct memory_block *, void *))
|
|
{
|
|
struct memory_block *mem = NULL;
|
|
struct mem_section *section;
|
|
unsigned long pfn, section_nr;
|
|
int ret;
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
|
|
section_nr = pfn_to_section_nr(pfn);
|
|
if (!present_section_nr(section_nr))
|
|
continue;
|
|
|
|
section = __nr_to_section(section_nr);
|
|
/* same memblock? */
|
|
if (mem)
|
|
if ((section_nr >= mem->start_section_nr) &&
|
|
(section_nr <= mem->end_section_nr))
|
|
continue;
|
|
|
|
mem = find_memory_block_hinted(section, mem);
|
|
if (!mem)
|
|
continue;
|
|
|
|
ret = func(mem, arg);
|
|
if (ret) {
|
|
kobject_put(&mem->dev.kobj);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
if (mem)
|
|
kobject_put(&mem->dev.kobj);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_MEMORY_HOTREMOVE
|
|
static int check_memblock_offlined_cb(struct memory_block *mem, void *arg)
|
|
{
|
|
int ret = !is_memblock_offlined(mem);
|
|
|
|
if (unlikely(ret)) {
|
|
phys_addr_t beginpa, endpa;
|
|
|
|
beginpa = PFN_PHYS(section_nr_to_pfn(mem->start_section_nr));
|
|
endpa = PFN_PHYS(section_nr_to_pfn(mem->end_section_nr + 1))-1;
|
|
pr_warn("removing memory fails, because memory [%pa-%pa] is onlined\n",
|
|
&beginpa, &endpa);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int check_cpu_on_node(pg_data_t *pgdat)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_present_cpu(cpu) {
|
|
if (cpu_to_node(cpu) == pgdat->node_id)
|
|
/*
|
|
* the cpu on this node isn't removed, and we can't
|
|
* offline this node.
|
|
*/
|
|
return -EBUSY;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void unmap_cpu_on_node(pg_data_t *pgdat)
|
|
{
|
|
#ifdef CONFIG_ACPI_NUMA
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
if (cpu_to_node(cpu) == pgdat->node_id)
|
|
numa_clear_node(cpu);
|
|
#endif
|
|
}
|
|
|
|
static int check_and_unmap_cpu_on_node(pg_data_t *pgdat)
|
|
{
|
|
int ret;
|
|
|
|
ret = check_cpu_on_node(pgdat);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* the node will be offlined when we come here, so we can clear
|
|
* the cpu_to_node() now.
|
|
*/
|
|
|
|
unmap_cpu_on_node(pgdat);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* try_offline_node
|
|
* @nid: the node ID
|
|
*
|
|
* Offline a node if all memory sections and cpus of the node are removed.
|
|
*
|
|
* NOTE: The caller must call lock_device_hotplug() to serialize hotplug
|
|
* and online/offline operations before this call.
|
|
*/
|
|
void try_offline_node(int nid)
|
|
{
|
|
pg_data_t *pgdat = NODE_DATA(nid);
|
|
unsigned long start_pfn = pgdat->node_start_pfn;
|
|
unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
|
|
unsigned long pfn;
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
|
|
unsigned long section_nr = pfn_to_section_nr(pfn);
|
|
|
|
if (!present_section_nr(section_nr))
|
|
continue;
|
|
|
|
if (pfn_to_nid(pfn) != nid)
|
|
continue;
|
|
|
|
/*
|
|
* some memory sections of this node are not removed, and we
|
|
* can't offline node now.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
if (check_and_unmap_cpu_on_node(pgdat))
|
|
return;
|
|
|
|
/*
|
|
* all memory/cpu of this node are removed, we can offline this
|
|
* node now.
|
|
*/
|
|
node_set_offline(nid);
|
|
unregister_one_node(nid);
|
|
}
|
|
EXPORT_SYMBOL(try_offline_node);
|
|
|
|
/**
|
|
* remove_memory
|
|
* @nid: the node ID
|
|
* @start: physical address of the region to remove
|
|
* @size: size of the region to remove
|
|
*
|
|
* NOTE: The caller must call lock_device_hotplug() to serialize hotplug
|
|
* and online/offline operations before this call, as required by
|
|
* try_offline_node().
|
|
*/
|
|
void __ref remove_memory(int nid, u64 start, u64 size)
|
|
{
|
|
int ret;
|
|
|
|
BUG_ON(check_hotplug_memory_range(start, size));
|
|
|
|
mem_hotplug_begin();
|
|
|
|
/*
|
|
* All memory blocks must be offlined before removing memory. Check
|
|
* whether all memory blocks in question are offline and trigger a BUG()
|
|
* if this is not the case.
|
|
*/
|
|
ret = walk_memory_range(PFN_DOWN(start), PFN_UP(start + size - 1), NULL,
|
|
check_memblock_offlined_cb);
|
|
if (ret)
|
|
BUG();
|
|
|
|
/* remove memmap entry */
|
|
firmware_map_remove(start, start + size, "System RAM");
|
|
memblock_free(start, size);
|
|
memblock_remove(start, size);
|
|
|
|
arch_remove_memory(start, size, NULL);
|
|
|
|
try_offline_node(nid);
|
|
|
|
mem_hotplug_done();
|
|
}
|
|
EXPORT_SYMBOL_GPL(remove_memory);
|
|
#endif /* CONFIG_MEMORY_HOTREMOVE */
|