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mm/migrate.c
76.9 KB
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// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Memory Migration functionality - linux/mm/migrate.c |
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* * Copyright (C) 2006 Silicon Graphics, Inc., Christoph Lameter * * Page migration was first developed in the context of the memory hotplug * project. The main authors of the migration code are: * * IWAMOTO Toshihiro <iwamoto@valinux.co.jp> * Hirokazu Takahashi <taka@valinux.co.jp> * Dave Hansen <haveblue@us.ibm.com> |
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* Christoph Lameter |
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*/ #include <linux/migrate.h> |
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#include <linux/export.h> |
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#include <linux/swap.h> |
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#include <linux/swapops.h> |
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#include <linux/pagemap.h> |
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#include <linux/buffer_head.h> |
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#include <linux/mm_inline.h> |
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#include <linux/nsproxy.h> |
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#include <linux/pagevec.h> |
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#include <linux/ksm.h> |
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#include <linux/rmap.h> #include <linux/topology.h> #include <linux/cpu.h> #include <linux/cpuset.h> |
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#include <linux/writeback.h> |
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#include <linux/mempolicy.h> #include <linux/vmalloc.h> |
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#include <linux/security.h> |
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#include <linux/backing-dev.h> |
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#include <linux/compaction.h> |
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#include <linux/syscalls.h> |
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#include <linux/compat.h> |
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#include <linux/hugetlb.h> |
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#include <linux/hugetlb_cgroup.h> |
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#include <linux/gfp.h> |
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#include <linux/pfn_t.h> |
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#include <linux/memremap.h> |
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#include <linux/userfaultfd_k.h> |
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#include <linux/balloon_compaction.h> |
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#include <linux/mmu_notifier.h> |
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#include <linux/page_idle.h> |
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#include <linux/page_owner.h> |
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#include <linux/sched/mm.h> |
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#include <linux/ptrace.h> |
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|
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#include <asm/tlbflush.h> |
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#define CREATE_TRACE_POINTS #include <trace/events/migrate.h> |
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#include "internal.h" |
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/* |
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* migrate_prep() needs to be called before we start compiling a list of pages |
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* to be migrated using isolate_lru_page(). If scheduling work on other CPUs is * undesirable, use migrate_prep_local() |
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*/ int migrate_prep(void) { |
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/* * Clear the LRU lists so pages can be isolated. * Note that pages may be moved off the LRU after we have * drained them. Those pages will fail to migrate like other * pages that may be busy. */ lru_add_drain_all(); return 0; } |
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/* Do the necessary work of migrate_prep but not if it involves other CPUs */ int migrate_prep_local(void) { lru_add_drain(); return 0; } |
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int isolate_movable_page(struct page *page, isolate_mode_t mode) |
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{ struct address_space *mapping; /* * Avoid burning cycles with pages that are yet under __free_pages(), * or just got freed under us. * * In case we 'win' a race for a movable page being freed under us and * raise its refcount preventing __free_pages() from doing its job * the put_page() at the end of this block will take care of * release this page, thus avoiding a nasty leakage. */ if (unlikely(!get_page_unless_zero(page))) goto out; /* * Check PageMovable before holding a PG_lock because page's owner * assumes anybody doesn't touch PG_lock of newly allocated page |
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* so unconditionally grabbing the lock ruins page's owner side. |
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*/ if (unlikely(!__PageMovable(page))) goto out_putpage; /* * As movable pages are not isolated from LRU lists, concurrent * compaction threads can race against page migration functions * as well as race against the releasing a page. * * In order to avoid having an already isolated movable page * being (wrongly) re-isolated while it is under migration, * or to avoid attempting to isolate pages being released, * lets be sure we have the page lock * before proceeding with the movable page isolation steps. */ if (unlikely(!trylock_page(page))) goto out_putpage; if (!PageMovable(page) || PageIsolated(page)) goto out_no_isolated; mapping = page_mapping(page); VM_BUG_ON_PAGE(!mapping, page); if (!mapping->a_ops->isolate_page(page, mode)) goto out_no_isolated; /* Driver shouldn't use PG_isolated bit of page->flags */ WARN_ON_ONCE(PageIsolated(page)); __SetPageIsolated(page); unlock_page(page); |
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return 0; |
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out_no_isolated: unlock_page(page); out_putpage: put_page(page); out: |
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return -EBUSY; |
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} /* It should be called on page which is PG_movable */ void putback_movable_page(struct page *page) { struct address_space *mapping; VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(!PageMovable(page), page); VM_BUG_ON_PAGE(!PageIsolated(page), page); mapping = page_mapping(page); mapping->a_ops->putback_page(page); __ClearPageIsolated(page); } |
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/* |
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* Put previously isolated pages back onto the appropriate lists * from where they were once taken off for compaction/migration. * |
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* This function shall be used whenever the isolated pageset has been * built from lru, balloon, hugetlbfs page. See isolate_migratepages_range() * and isolate_huge_page(). |
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*/ void putback_movable_pages(struct list_head *l) { struct page *page; struct page *page2; list_for_each_entry_safe(page, page2, l, lru) { |
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if (unlikely(PageHuge(page))) { putback_active_hugepage(page); continue; } |
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list_del(&page->lru); |
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/* * We isolated non-lru movable page so here we can use * __PageMovable because LRU page's mapping cannot have * PAGE_MAPPING_MOVABLE. */ |
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if (unlikely(__PageMovable(page))) { |
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VM_BUG_ON_PAGE(!PageIsolated(page), page); lock_page(page); if (PageMovable(page)) putback_movable_page(page); else __ClearPageIsolated(page); unlock_page(page); put_page(page); } else { |
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mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_cache(page), -hpage_nr_pages(page)); |
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putback_lru_page(page); |
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} |
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} |
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} |
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/* * Restore a potential migration pte to a working pte entry */ |
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static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma, |
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unsigned long addr, void *old) |
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{ |
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struct page_vma_mapped_walk pvmw = { .page = old, .vma = vma, .address = addr, .flags = PVMW_SYNC | PVMW_MIGRATION, }; struct page *new; pte_t pte; |
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swp_entry_t entry; |
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|
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VM_BUG_ON_PAGE(PageTail(page), page); while (page_vma_mapped_walk(&pvmw)) { |
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if (PageKsm(page)) new = page; else new = page - pvmw.page->index + linear_page_index(vma, pvmw.address); |
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|
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#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION /* PMD-mapped THP migration entry */ if (!pvmw.pte) { VM_BUG_ON_PAGE(PageHuge(page) || !PageTransCompound(page), page); remove_migration_pmd(&pvmw, new); continue; } #endif |
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get_page(new); pte = pte_mkold(mk_pte(new, READ_ONCE(vma->vm_page_prot))); if (pte_swp_soft_dirty(*pvmw.pte)) pte = pte_mksoft_dirty(pte); |
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|
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/* * Recheck VMA as permissions can change since migration started */ entry = pte_to_swp_entry(*pvmw.pte); if (is_write_migration_entry(entry)) pte = maybe_mkwrite(pte, vma); |
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|
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if (unlikely(is_zone_device_page(new))) { if (is_device_private_page(new)) { entry = make_device_private_entry(new, pte_write(pte)); pte = swp_entry_to_pte(entry); } else if (is_device_public_page(new)) { pte = pte_mkdevmap(pte); |
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} |
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} |
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|
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#ifdef CONFIG_HUGETLB_PAGE |
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if (PageHuge(new)) { pte = pte_mkhuge(pte); pte = arch_make_huge_pte(pte, vma, new, 0); |
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set_huge_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte); |
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if (PageAnon(new)) hugepage_add_anon_rmap(new, vma, pvmw.address); else page_dup_rmap(new, true); |
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} else #endif { set_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte); |
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|
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if (PageAnon(new)) page_add_anon_rmap(new, vma, pvmw.address, false); else page_add_file_rmap(new, false); } |
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if (vma->vm_flags & VM_LOCKED && !PageTransCompound(new)) mlock_vma_page(new); |
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if (PageTransHuge(page) && PageMlocked(page)) clear_page_mlock(page); |
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/* No need to invalidate - it was non-present before */ update_mmu_cache(vma, pvmw.address, pvmw.pte); } |
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|
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return true; |
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} /* |
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* Get rid of all migration entries and replace them by * references to the indicated page. */ |
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void remove_migration_ptes(struct page *old, struct page *new, bool locked) |
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{ |
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struct rmap_walk_control rwc = { .rmap_one = remove_migration_pte, .arg = old, }; |
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if (locked) rmap_walk_locked(new, &rwc); else rmap_walk(new, &rwc); |
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} /* |
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* Something used the pte of a page under migration. We need to * get to the page and wait until migration is finished. * When we return from this function the fault will be retried. |
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*/ |
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void __migration_entry_wait(struct mm_struct *mm, pte_t *ptep, |
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spinlock_t *ptl) |
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{ |
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pte_t pte; |
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swp_entry_t entry; struct page *page; |
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spin_lock(ptl); |
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pte = *ptep; if (!is_swap_pte(pte)) goto out; entry = pte_to_swp_entry(pte); if (!is_migration_entry(entry)) goto out; page = migration_entry_to_page(entry); |
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/* |
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* Once page cache replacement of page migration started, page_count |
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* is zero; but we must not call put_and_wait_on_page_locked() without * a ref. Use get_page_unless_zero(), and just fault again if it fails. |
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*/ if (!get_page_unless_zero(page)) goto out; |
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pte_unmap_unlock(ptep, ptl); |
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put_and_wait_on_page_locked(page); |
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return; out: pte_unmap_unlock(ptep, ptl); } |
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void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd, unsigned long address) { spinlock_t *ptl = pte_lockptr(mm, pmd); pte_t *ptep = pte_offset_map(pmd, address); __migration_entry_wait(mm, ptep, ptl); } |
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void migration_entry_wait_huge(struct vm_area_struct *vma, struct mm_struct *mm, pte_t *pte) |
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{ |
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spinlock_t *ptl = huge_pte_lockptr(hstate_vma(vma), mm, pte); |
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__migration_entry_wait(mm, pte, ptl); } |
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#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION void pmd_migration_entry_wait(struct mm_struct *mm, pmd_t *pmd) { spinlock_t *ptl; struct page *page; ptl = pmd_lock(mm, pmd); if (!is_pmd_migration_entry(*pmd)) goto unlock; page = migration_entry_to_page(pmd_to_swp_entry(*pmd)); if (!get_page_unless_zero(page)) goto unlock; spin_unlock(ptl); |
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put_and_wait_on_page_locked(page); |
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return; unlock: spin_unlock(ptl); } #endif |
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static int expected_page_refs(struct address_space *mapping, struct page *page) |
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{ int expected_count = 1; /* * Device public or private pages have an extra refcount as they are * ZONE_DEVICE pages. */ expected_count += is_device_private_page(page); expected_count += is_device_public_page(page); |
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if (mapping) |
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expected_count += hpage_nr_pages(page) + page_has_private(page); return expected_count; } |
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/* |
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* Replace the page in the mapping. |
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* * The number of remaining references must be: * 1 for anonymous pages without a mapping * 2 for pages with a mapping |
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* 3 for pages with a mapping and PagePrivate/PagePrivate2 set. |
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*/ |
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int migrate_page_move_mapping(struct address_space *mapping, |
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struct page *newpage, struct page *page, enum migrate_mode mode, |
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int extra_count) |
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{ |
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XA_STATE(xas, &mapping->i_pages, page_index(page)); |
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struct zone *oldzone, *newzone; int dirty; |
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int expected_count = expected_page_refs(mapping, page) + extra_count; |
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|
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if (!mapping) { |
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/* Anonymous page without mapping */ |
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if (page_count(page) != expected_count) |
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return -EAGAIN; |
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/* No turning back from here */ |
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newpage->index = page->index; newpage->mapping = page->mapping; if (PageSwapBacked(page)) |
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__SetPageSwapBacked(newpage); |
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|
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return MIGRATEPAGE_SUCCESS; |
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} |
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oldzone = page_zone(page); newzone = page_zone(newpage); |
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xas_lock_irq(&xas); |
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if (page_count(page) != expected_count || xas_load(&xas) != page) { xas_unlock_irq(&xas); |
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return -EAGAIN; |
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} |
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if (!page_ref_freeze(page, expected_count)) { |
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xas_unlock_irq(&xas); |
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return -EAGAIN; } |
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/* |
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* Now we know that no one else is looking at the page: * no turning back from here. |
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*/ |
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newpage->index = page->index; newpage->mapping = page->mapping; |
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page_ref_add(newpage, hpage_nr_pages(page)); /* add cache reference */ |
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if (PageSwapBacked(page)) { __SetPageSwapBacked(newpage); if (PageSwapCache(page)) { SetPageSwapCache(newpage); set_page_private(newpage, page_private(page)); } } else { VM_BUG_ON_PAGE(PageSwapCache(page), page); |
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} |
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/* Move dirty while page refs frozen and newpage not yet exposed */ dirty = PageDirty(page); if (dirty) { ClearPageDirty(page); SetPageDirty(newpage); } |
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xas_store(&xas, newpage); |
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if (PageTransHuge(page)) { int i; |
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|
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for (i = 1; i < HPAGE_PMD_NR; i++) { |
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xas_next(&xas); |
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xas_store(&xas, newpage); |
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} |
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} |
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/* |
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* Drop cache reference from old page by unfreezing * to one less reference. |
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* We know this isn't the last reference. */ |
e71769ae5 mm: enable thp mi... |
450 |
page_ref_unfreeze(page, expected_count - hpage_nr_pages(page)); |
7cf9c2c76 [PATCH] radix-tre... |
451 |
|
89eb946a7 mm: Convert page ... |
452 |
xas_unlock(&xas); |
42cb14b11 mm: migrate dirty... |
453 |
/* Leave irq disabled to prevent preemption while updating stats */ |
0e8c7d0fd page migration: f... |
454 455 456 457 458 459 460 |
/* * If moved to a different zone then also account * the page for that zone. Other VM counters will be * taken care of when we establish references to the * new page and drop references to the old page. * * Note that anonymous pages are accounted for |
4b9d0fab7 mm: rename NR_ANO... |
461 |
* via NR_FILE_PAGES and NR_ANON_MAPPED if they |
0e8c7d0fd page migration: f... |
462 463 |
* are mapped to swap space. */ |
42cb14b11 mm: migrate dirty... |
464 |
if (newzone != oldzone) { |
11fb99898 mm: move most fil... |
465 466 |
__dec_node_state(oldzone->zone_pgdat, NR_FILE_PAGES); __inc_node_state(newzone->zone_pgdat, NR_FILE_PAGES); |
42cb14b11 mm: migrate dirty... |
467 |
if (PageSwapBacked(page) && !PageSwapCache(page)) { |
11fb99898 mm: move most fil... |
468 469 |
__dec_node_state(oldzone->zone_pgdat, NR_SHMEM); __inc_node_state(newzone->zone_pgdat, NR_SHMEM); |
42cb14b11 mm: migrate dirty... |
470 471 |
} if (dirty && mapping_cap_account_dirty(mapping)) { |
11fb99898 mm: move most fil... |
472 |
__dec_node_state(oldzone->zone_pgdat, NR_FILE_DIRTY); |
5a1c84b40 mm: remove reclai... |
473 |
__dec_zone_state(oldzone, NR_ZONE_WRITE_PENDING); |
11fb99898 mm: move most fil... |
474 |
__inc_node_state(newzone->zone_pgdat, NR_FILE_DIRTY); |
5a1c84b40 mm: remove reclai... |
475 |
__inc_zone_state(newzone, NR_ZONE_WRITE_PENDING); |
42cb14b11 mm: migrate dirty... |
476 |
} |
4b02108ac mm: oom analysis:... |
477 |
} |
42cb14b11 mm: migrate dirty... |
478 |
local_irq_enable(); |
b20a35035 [PATCH] page migr... |
479 |
|
78bd52097 mm: adjust addres... |
480 |
return MIGRATEPAGE_SUCCESS; |
b20a35035 [PATCH] page migr... |
481 |
} |
1118dce77 mm: Export migrat... |
482 |
EXPORT_SYMBOL(migrate_page_move_mapping); |
b20a35035 [PATCH] page migr... |
483 484 |
/* |
290408d4a hugetlb: hugepage... |
485 486 487 488 489 490 |
* The expected number of remaining references is the same as that * of migrate_page_move_mapping(). */ int migrate_huge_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page) { |
89eb946a7 mm: Convert page ... |
491 |
XA_STATE(xas, &mapping->i_pages, page_index(page)); |
290408d4a hugetlb: hugepage... |
492 |
int expected_count; |
290408d4a hugetlb: hugepage... |
493 |
|
89eb946a7 mm: Convert page ... |
494 |
xas_lock_irq(&xas); |
290408d4a hugetlb: hugepage... |
495 |
expected_count = 2 + page_has_private(page); |
89eb946a7 mm: Convert page ... |
496 497 |
if (page_count(page) != expected_count || xas_load(&xas) != page) { xas_unlock_irq(&xas); |
290408d4a hugetlb: hugepage... |
498 499 |
return -EAGAIN; } |
fe896d187 mm: introduce pag... |
500 |
if (!page_ref_freeze(page, expected_count)) { |
89eb946a7 mm: Convert page ... |
501 |
xas_unlock_irq(&xas); |
290408d4a hugetlb: hugepage... |
502 503 |
return -EAGAIN; } |
cf4b769ab mm: page migratio... |
504 505 |
newpage->index = page->index; newpage->mapping = page->mapping; |
6a93ca8fd mm: migrate: do n... |
506 |
|
290408d4a hugetlb: hugepage... |
507 |
get_page(newpage); |
89eb946a7 mm: Convert page ... |
508 |
xas_store(&xas, newpage); |
290408d4a hugetlb: hugepage... |
509 |
|
fe896d187 mm: introduce pag... |
510 |
page_ref_unfreeze(page, expected_count - 1); |
290408d4a hugetlb: hugepage... |
511 |
|
89eb946a7 mm: Convert page ... |
512 |
xas_unlock_irq(&xas); |
6a93ca8fd mm: migrate: do n... |
513 |
|
78bd52097 mm: adjust addres... |
514 |
return MIGRATEPAGE_SUCCESS; |
290408d4a hugetlb: hugepage... |
515 516 517 |
} /* |
30b0a105d mm: thp: give tra... |
518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 |
* Gigantic pages are so large that we do not guarantee that page++ pointer * arithmetic will work across the entire page. We need something more * specialized. */ static void __copy_gigantic_page(struct page *dst, struct page *src, int nr_pages) { int i; struct page *dst_base = dst; struct page *src_base = src; for (i = 0; i < nr_pages; ) { cond_resched(); copy_highpage(dst, src); i++; dst = mem_map_next(dst, dst_base, i); src = mem_map_next(src, src_base, i); } } static void copy_huge_page(struct page *dst, struct page *src) { int i; int nr_pages; if (PageHuge(src)) { /* hugetlbfs page */ struct hstate *h = page_hstate(src); nr_pages = pages_per_huge_page(h); if (unlikely(nr_pages > MAX_ORDER_NR_PAGES)) { __copy_gigantic_page(dst, src, nr_pages); return; } } else { /* thp page */ BUG_ON(!PageTransHuge(src)); nr_pages = hpage_nr_pages(src); } for (i = 0; i < nr_pages; i++) { cond_resched(); copy_highpage(dst + i, src + i); } } /* |
b20a35035 [PATCH] page migr... |
566 567 |
* Copy the page to its new location */ |
2916ecc0f mm/migrate: new m... |
568 |
void migrate_page_states(struct page *newpage, struct page *page) |
b20a35035 [PATCH] page migr... |
569 |
{ |
7851a45cd mm: numa: Copy cp... |
570 |
int cpupid; |
b20a35035 [PATCH] page migr... |
571 572 573 574 575 576 |
if (PageError(page)) SetPageError(newpage); if (PageReferenced(page)) SetPageReferenced(newpage); if (PageUptodate(page)) SetPageUptodate(newpage); |
894bc3104 Unevictable LRU I... |
577 |
if (TestClearPageActive(page)) { |
309381fea mm: dump page whe... |
578 |
VM_BUG_ON_PAGE(PageUnevictable(page), page); |
b20a35035 [PATCH] page migr... |
579 |
SetPageActive(newpage); |
418b27ef5 mm: remove unevic... |
580 581 |
} else if (TestClearPageUnevictable(page)) SetPageUnevictable(newpage); |
1899ad18c mm: workingset: t... |
582 583 |
if (PageWorkingset(page)) SetPageWorkingset(newpage); |
b20a35035 [PATCH] page migr... |
584 585 586 587 |
if (PageChecked(page)) SetPageChecked(newpage); if (PageMappedToDisk(page)) SetPageMappedToDisk(newpage); |
42cb14b11 mm: migrate dirty... |
588 589 590 |
/* Move dirty on pages not done by migrate_page_move_mapping() */ if (PageDirty(page)) SetPageDirty(newpage); |
b20a35035 [PATCH] page migr... |
591 |
|
33c3fc71c mm: introduce idl... |
592 593 594 595 |
if (page_is_young(page)) set_page_young(newpage); if (page_is_idle(page)) set_page_idle(newpage); |
7851a45cd mm: numa: Copy cp... |
596 597 598 599 600 601 |
/* * Copy NUMA information to the new page, to prevent over-eager * future migrations of this same page. */ cpupid = page_cpupid_xchg_last(page, -1); page_cpupid_xchg_last(newpage, cpupid); |
e9995ef97 ksm: rmap_walk to... |
602 |
ksm_migrate_page(newpage, page); |
c8d6553b9 ksm: make KSM pag... |
603 604 605 606 |
/* * Please do not reorder this without considering how mm/ksm.c's * get_ksm_page() depends upon ksm_migrate_page() and PageSwapCache(). */ |
b3b3a99c5 mm/migrate: check... |
607 608 |
if (PageSwapCache(page)) ClearPageSwapCache(page); |
b20a35035 [PATCH] page migr... |
609 610 |
ClearPagePrivate(page); set_page_private(page, 0); |
b20a35035 [PATCH] page migr... |
611 612 613 614 615 616 617 |
/* * If any waiters have accumulated on the new page then * wake them up. */ if (PageWriteback(newpage)) end_page_writeback(newpage); |
d435edca9 mm, page_owner: c... |
618 619 |
copy_page_owner(page, newpage); |
74485cf2b mm: migrate: cons... |
620 621 |
mem_cgroup_migrate(page, newpage); |
b20a35035 [PATCH] page migr... |
622 |
} |
2916ecc0f mm/migrate: new m... |
623 624 625 626 627 628 629 630 631 632 633 |
EXPORT_SYMBOL(migrate_page_states); void migrate_page_copy(struct page *newpage, struct page *page) { if (PageHuge(page) || PageTransHuge(page)) copy_huge_page(newpage, page); else copy_highpage(newpage, page); migrate_page_states(newpage, page); } |
1118dce77 mm: Export migrat... |
634 |
EXPORT_SYMBOL(migrate_page_copy); |
b20a35035 [PATCH] page migr... |
635 |
|
1d8b85ccf [PATCH] page migr... |
636 637 638 |
/************************************************************ * Migration functions ***********************************************************/ |
b20a35035 [PATCH] page migr... |
639 |
/* |
bda807d44 mm: migrate: supp... |
640 |
* Common logic to directly migrate a single LRU page suitable for |
266cf658e FS-Cache: Recruit... |
641 |
* pages that do not use PagePrivate/PagePrivate2. |
b20a35035 [PATCH] page migr... |
642 643 644 |
* * Pages are locked upon entry and exit. */ |
2d1db3b11 [PATCH] page migr... |
645 |
int migrate_page(struct address_space *mapping, |
a6bc32b89 mm: compaction: i... |
646 647 |
struct page *newpage, struct page *page, enum migrate_mode mode) |
b20a35035 [PATCH] page migr... |
648 649 650 651 |
{ int rc; BUG_ON(PageWriteback(page)); /* Writeback must be complete */ |
ab41ee687 mm: migrate: drop... |
652 |
rc = migrate_page_move_mapping(mapping, newpage, page, mode, 0); |
b20a35035 [PATCH] page migr... |
653 |
|
78bd52097 mm: adjust addres... |
654 |
if (rc != MIGRATEPAGE_SUCCESS) |
b20a35035 [PATCH] page migr... |
655 |
return rc; |
2916ecc0f mm/migrate: new m... |
656 657 658 659 |
if (mode != MIGRATE_SYNC_NO_COPY) migrate_page_copy(newpage, page); else migrate_page_states(newpage, page); |
78bd52097 mm: adjust addres... |
660 |
return MIGRATEPAGE_SUCCESS; |
b20a35035 [PATCH] page migr... |
661 662 |
} EXPORT_SYMBOL(migrate_page); |
9361401eb [PATCH] BLOCK: Ma... |
663 |
#ifdef CONFIG_BLOCK |
84ade7c15 mm: migrate: move... |
664 665 666 667 668 669 670 671 672 |
/* Returns true if all buffers are successfully locked */ static bool buffer_migrate_lock_buffers(struct buffer_head *head, enum migrate_mode mode) { struct buffer_head *bh = head; /* Simple case, sync compaction */ if (mode != MIGRATE_ASYNC) { do { |
84ade7c15 mm: migrate: move... |
673 674 675 676 677 678 679 680 681 682 |
lock_buffer(bh); bh = bh->b_this_page; } while (bh != head); return true; } /* async case, we cannot block on lock_buffer so use trylock_buffer */ do { |
84ade7c15 mm: migrate: move... |
683 684 685 686 687 688 |
if (!trylock_buffer(bh)) { /* * We failed to lock the buffer and cannot stall in * async migration. Release the taken locks */ struct buffer_head *failed_bh = bh; |
84ade7c15 mm: migrate: move... |
689 690 691 |
bh = head; while (bh != failed_bh) { unlock_buffer(bh); |
84ade7c15 mm: migrate: move... |
692 693 694 695 696 697 698 699 700 |
bh = bh->b_this_page; } return false; } bh = bh->b_this_page; } while (bh != head); return true; } |
89cb0888c mm: migrate: prov... |
701 702 703 |
static int __buffer_migrate_page(struct address_space *mapping, struct page *newpage, struct page *page, enum migrate_mode mode, bool check_refs) |
1d8b85ccf [PATCH] page migr... |
704 |
{ |
1d8b85ccf [PATCH] page migr... |
705 706 |
struct buffer_head *bh, *head; int rc; |
cc4f11e69 mm: migrate: lock... |
707 |
int expected_count; |
1d8b85ccf [PATCH] page migr... |
708 |
|
1d8b85ccf [PATCH] page migr... |
709 |
if (!page_has_buffers(page)) |
a6bc32b89 mm: compaction: i... |
710 |
return migrate_page(mapping, newpage, page, mode); |
1d8b85ccf [PATCH] page migr... |
711 |
|
cc4f11e69 mm: migrate: lock... |
712 |
/* Check whether page does not have extra refs before we do more work */ |
f900482da mm/migrate.c: cle... |
713 |
expected_count = expected_page_refs(mapping, page); |
cc4f11e69 mm: migrate: lock... |
714 715 |
if (page_count(page) != expected_count) return -EAGAIN; |
1d8b85ccf [PATCH] page migr... |
716 |
|
cc4f11e69 mm: migrate: lock... |
717 718 719 |
head = page_buffers(page); if (!buffer_migrate_lock_buffers(head, mode)) return -EAGAIN; |
1d8b85ccf [PATCH] page migr... |
720 |
|
89cb0888c mm: migrate: prov... |
721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 |
if (check_refs) { bool busy; bool invalidated = false; recheck_buffers: busy = false; spin_lock(&mapping->private_lock); bh = head; do { if (atomic_read(&bh->b_count)) { busy = true; break; } bh = bh->b_this_page; } while (bh != head); spin_unlock(&mapping->private_lock); if (busy) { if (invalidated) { rc = -EAGAIN; goto unlock_buffers; } invalidate_bh_lrus(); invalidated = true; goto recheck_buffers; } } |
ab41ee687 mm: migrate: drop... |
747 |
rc = migrate_page_move_mapping(mapping, newpage, page, mode, 0); |
78bd52097 mm: adjust addres... |
748 |
if (rc != MIGRATEPAGE_SUCCESS) |
cc4f11e69 mm: migrate: lock... |
749 |
goto unlock_buffers; |
1d8b85ccf [PATCH] page migr... |
750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 |
ClearPagePrivate(page); set_page_private(newpage, page_private(page)); set_page_private(page, 0); put_page(page); get_page(newpage); bh = head; do { set_bh_page(bh, newpage, bh_offset(bh)); bh = bh->b_this_page; } while (bh != head); SetPagePrivate(newpage); |
2916ecc0f mm/migrate: new m... |
765 766 767 768 |
if (mode != MIGRATE_SYNC_NO_COPY) migrate_page_copy(newpage, page); else migrate_page_states(newpage, page); |
1d8b85ccf [PATCH] page migr... |
769 |
|
cc4f11e69 mm: migrate: lock... |
770 771 |
rc = MIGRATEPAGE_SUCCESS; unlock_buffers: |
1d8b85ccf [PATCH] page migr... |
772 773 774 |
bh = head; do { unlock_buffer(bh); |
1d8b85ccf [PATCH] page migr... |
775 776 777 |
bh = bh->b_this_page; } while (bh != head); |
cc4f11e69 mm: migrate: lock... |
778 |
return rc; |
1d8b85ccf [PATCH] page migr... |
779 |
} |
89cb0888c mm: migrate: prov... |
780 781 782 783 784 785 786 787 788 789 790 |
/* * Migration function for pages with buffers. This function can only be used * if the underlying filesystem guarantees that no other references to "page" * exist. For example attached buffer heads are accessed only under page lock. */ int buffer_migrate_page(struct address_space *mapping, struct page *newpage, struct page *page, enum migrate_mode mode) { return __buffer_migrate_page(mapping, newpage, page, mode, false); } |
1d8b85ccf [PATCH] page migr... |
791 |
EXPORT_SYMBOL(buffer_migrate_page); |
89cb0888c mm: migrate: prov... |
792 793 794 795 796 797 798 799 800 801 802 803 |
/* * Same as above except that this variant is more careful and checks that there * are also no buffer head references. This function is the right one for * mappings where buffer heads are directly looked up and referenced (such as * block device mappings). */ int buffer_migrate_page_norefs(struct address_space *mapping, struct page *newpage, struct page *page, enum migrate_mode mode) { return __buffer_migrate_page(mapping, newpage, page, mode, true); } |
9361401eb [PATCH] BLOCK: Ma... |
804 |
#endif |
1d8b85ccf [PATCH] page migr... |
805 |
|
04e62a29b [PATCH] More page... |
806 807 808 809 |
/* * Writeback a page to clean the dirty state */ static int writeout(struct address_space *mapping, struct page *page) |
8351a6e47 [PATCH] page migr... |
810 |
{ |
04e62a29b [PATCH] More page... |
811 812 813 814 815 |
struct writeback_control wbc = { .sync_mode = WB_SYNC_NONE, .nr_to_write = 1, .range_start = 0, .range_end = LLONG_MAX, |
04e62a29b [PATCH] More page... |
816 817 818 819 820 821 822 823 824 825 826 |
.for_reclaim = 1 }; int rc; if (!mapping->a_ops->writepage) /* No write method for the address space */ return -EINVAL; if (!clear_page_dirty_for_io(page)) /* Someone else already triggered a write */ return -EAGAIN; |
8351a6e47 [PATCH] page migr... |
827 |
/* |
04e62a29b [PATCH] More page... |
828 829 830 831 832 833 |
* A dirty page may imply that the underlying filesystem has * the page on some queue. So the page must be clean for * migration. Writeout may mean we loose the lock and the * page state is no longer what we checked for earlier. * At this point we know that the migration attempt cannot * be successful. |
8351a6e47 [PATCH] page migr... |
834 |
*/ |
e388466de mm: make remove_m... |
835 |
remove_migration_ptes(page, page, false); |
8351a6e47 [PATCH] page migr... |
836 |
|
04e62a29b [PATCH] More page... |
837 |
rc = mapping->a_ops->writepage(page, &wbc); |
8351a6e47 [PATCH] page migr... |
838 |
|
04e62a29b [PATCH] More page... |
839 840 841 |
if (rc != AOP_WRITEPAGE_ACTIVATE) /* unlocked. Relock */ lock_page(page); |
bda8550de migration: fix wr... |
842 |
return (rc < 0) ? -EIO : -EAGAIN; |
04e62a29b [PATCH] More page... |
843 844 845 846 847 848 |
} /* * Default handling if a filesystem does not provide a migration function. */ static int fallback_migrate_page(struct address_space *mapping, |
a6bc32b89 mm: compaction: i... |
849 |
struct page *newpage, struct page *page, enum migrate_mode mode) |
04e62a29b [PATCH] More page... |
850 |
{ |
b969c4ab9 mm: compaction: d... |
851 |
if (PageDirty(page)) { |
a6bc32b89 mm: compaction: i... |
852 |
/* Only writeback pages in full synchronous migration */ |
2916ecc0f mm/migrate: new m... |
853 854 855 856 857 |
switch (mode) { case MIGRATE_SYNC: case MIGRATE_SYNC_NO_COPY: break; default: |
b969c4ab9 mm: compaction: d... |
858 |
return -EBUSY; |
2916ecc0f mm/migrate: new m... |
859 |
} |
04e62a29b [PATCH] More page... |
860 |
return writeout(mapping, page); |
b969c4ab9 mm: compaction: d... |
861 |
} |
8351a6e47 [PATCH] page migr... |
862 863 864 865 866 |
/* * Buffers may be managed in a filesystem specific way. * We must have no buffers or drop them. */ |
266cf658e FS-Cache: Recruit... |
867 |
if (page_has_private(page) && |
8351a6e47 [PATCH] page migr... |
868 |
!try_to_release_page(page, GFP_KERNEL)) |
806031bb5 mm, migrate: imme... |
869 |
return mode == MIGRATE_SYNC ? -EAGAIN : -EBUSY; |
8351a6e47 [PATCH] page migr... |
870 |
|
a6bc32b89 mm: compaction: i... |
871 |
return migrate_page(mapping, newpage, page, mode); |
8351a6e47 [PATCH] page migr... |
872 |
} |
1d8b85ccf [PATCH] page migr... |
873 |
/* |
e24f0b8f7 [PATCH] page migr... |
874 875 876 877 878 |
* Move a page to a newly allocated page * The page is locked and all ptes have been successfully removed. * * The new page will have replaced the old page if this function * is successful. |
894bc3104 Unevictable LRU I... |
879 880 881 |
* * Return value: * < 0 - error code |
78bd52097 mm: adjust addres... |
882 |
* MIGRATEPAGE_SUCCESS - success |
e24f0b8f7 [PATCH] page migr... |
883 |
*/ |
3fe2011ff mm: migration: al... |
884 |
static int move_to_new_page(struct page *newpage, struct page *page, |
5c3f9a673 mm: page migratio... |
885 |
enum migrate_mode mode) |
e24f0b8f7 [PATCH] page migr... |
886 887 |
{ struct address_space *mapping; |
bda807d44 mm: migrate: supp... |
888 889 |
int rc = -EAGAIN; bool is_lru = !__PageMovable(page); |
e24f0b8f7 [PATCH] page migr... |
890 |
|
7db7671f8 mm: page migratio... |
891 892 |
VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(!PageLocked(newpage), newpage); |
e24f0b8f7 [PATCH] page migr... |
893 |
|
e24f0b8f7 [PATCH] page migr... |
894 |
mapping = page_mapping(page); |
bda807d44 mm: migrate: supp... |
895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 |
if (likely(is_lru)) { if (!mapping) rc = migrate_page(mapping, newpage, page, mode); else if (mapping->a_ops->migratepage) /* * Most pages have a mapping and most filesystems * provide a migratepage callback. Anonymous pages * are part of swap space which also has its own * migratepage callback. This is the most common path * for page migration. */ rc = mapping->a_ops->migratepage(mapping, newpage, page, mode); else rc = fallback_migrate_page(mapping, newpage, page, mode); } else { |
e24f0b8f7 [PATCH] page migr... |
913 |
/* |
bda807d44 mm: migrate: supp... |
914 915 |
* In case of non-lru page, it could be released after * isolation step. In that case, we shouldn't try migration. |
e24f0b8f7 [PATCH] page migr... |
916 |
*/ |
bda807d44 mm: migrate: supp... |
917 918 919 920 921 922 923 924 925 926 927 928 |
VM_BUG_ON_PAGE(!PageIsolated(page), page); if (!PageMovable(page)) { rc = MIGRATEPAGE_SUCCESS; __ClearPageIsolated(page); goto out; } rc = mapping->a_ops->migratepage(mapping, newpage, page, mode); WARN_ON_ONCE(rc == MIGRATEPAGE_SUCCESS && !PageIsolated(page)); } |
e24f0b8f7 [PATCH] page migr... |
929 |
|
5c3f9a673 mm: page migratio... |
930 931 932 933 934 |
/* * When successful, old pagecache page->mapping must be cleared before * page is freed; but stats require that PageAnon be left as PageAnon. */ if (rc == MIGRATEPAGE_SUCCESS) { |
bda807d44 mm: migrate: supp... |
935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 |
if (__PageMovable(page)) { VM_BUG_ON_PAGE(!PageIsolated(page), page); /* * We clear PG_movable under page_lock so any compactor * cannot try to migrate this page. */ __ClearPageIsolated(page); } /* * Anonymous and movable page->mapping will be cleard by * free_pages_prepare so don't reset it here for keeping * the type to work PageAnon, for example. */ if (!PageMappingFlags(page)) |
5c3f9a673 mm: page migratio... |
951 |
page->mapping = NULL; |
d2b2c6dd2 mm/migrate.c: add... |
952 953 954 955 956 957 |
if (unlikely(is_zone_device_page(newpage))) { if (is_device_public_page(newpage)) flush_dcache_page(newpage); } else flush_dcache_page(newpage); |
3fe2011ff mm: migration: al... |
958 |
} |
bda807d44 mm: migrate: supp... |
959 |
out: |
e24f0b8f7 [PATCH] page migr... |
960 961 |
return rc; } |
0dabec93d mm: migration: cl... |
962 |
static int __unmap_and_move(struct page *page, struct page *newpage, |
9c620e2bc mm: remove offlin... |
963 |
int force, enum migrate_mode mode) |
e24f0b8f7 [PATCH] page migr... |
964 |
{ |
0dabec93d mm: migration: cl... |
965 |
int rc = -EAGAIN; |
2ebba6b7e mm: unmapped page... |
966 |
int page_was_mapped = 0; |
3f6c82728 mm: migration: ta... |
967 |
struct anon_vma *anon_vma = NULL; |
bda807d44 mm: migrate: supp... |
968 |
bool is_lru = !__PageMovable(page); |
95a402c38 [PATCH] page migr... |
969 |
|
529ae9aaa mm: rename page t... |
970 |
if (!trylock_page(page)) { |
a6bc32b89 mm: compaction: i... |
971 |
if (!force || mode == MIGRATE_ASYNC) |
0dabec93d mm: migration: cl... |
972 |
goto out; |
3e7d34497 mm: vmscan: recla... |
973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 |
/* * It's not safe for direct compaction to call lock_page. * For example, during page readahead pages are added locked * to the LRU. Later, when the IO completes the pages are * marked uptodate and unlocked. However, the queueing * could be merging multiple pages for one bio (e.g. * mpage_readpages). If an allocation happens for the * second or third page, the process can end up locking * the same page twice and deadlocking. Rather than * trying to be clever about what pages can be locked, * avoid the use of lock_page for direct compaction * altogether. */ if (current->flags & PF_MEMALLOC) |
0dabec93d mm: migration: cl... |
988 |
goto out; |
3e7d34497 mm: vmscan: recla... |
989 |
|
e24f0b8f7 [PATCH] page migr... |
990 991 992 993 |
lock_page(page); } if (PageWriteback(page)) { |
11bc82d67 mm: compaction: U... |
994 |
/* |
fed5b64a9 mm/migrate: fix c... |
995 |
* Only in the case of a full synchronous migration is it |
a6bc32b89 mm: compaction: i... |
996 997 998 |
* necessary to wait for PageWriteback. In the async case, * the retry loop is too short and in the sync-light case, * the overhead of stalling is too much |
11bc82d67 mm: compaction: U... |
999 |
*/ |
2916ecc0f mm/migrate: new m... |
1000 1001 1002 1003 1004 |
switch (mode) { case MIGRATE_SYNC: case MIGRATE_SYNC_NO_COPY: break; default: |
11bc82d67 mm: compaction: U... |
1005 |
rc = -EBUSY; |
0a31bc97c mm: memcontrol: r... |
1006 |
goto out_unlock; |
11bc82d67 mm: compaction: U... |
1007 1008 |
} if (!force) |
0a31bc97c mm: memcontrol: r... |
1009 |
goto out_unlock; |
e24f0b8f7 [PATCH] page migr... |
1010 1011 |
wait_on_page_writeback(page); } |
03f15c86c mm: simplify page... |
1012 |
|
e24f0b8f7 [PATCH] page migr... |
1013 |
/* |
dc386d4d1 memory unplug: mi... |
1014 1015 |
* By try_to_unmap(), page->mapcount goes down to 0 here. In this case, * we cannot notice that anon_vma is freed while we migrates a page. |
1ce82b69e mm: fix migration... |
1016 |
* This get_anon_vma() delays freeing anon_vma pointer until the end |
dc386d4d1 memory unplug: mi... |
1017 |
* of migration. File cache pages are no problem because of page_lock() |
989f89c57 fix rcu_read_lock... |
1018 1019 |
* File Caches may use write_page() or lock_page() in migration, then, * just care Anon page here. |
03f15c86c mm: simplify page... |
1020 1021 1022 1023 1024 1025 |
* * Only page_get_anon_vma() understands the subtleties of * getting a hold on an anon_vma from outside one of its mms. * But if we cannot get anon_vma, then we won't need it anyway, * because that implies that the anon page is no longer mapped * (and cannot be remapped so long as we hold the page lock). |
dc386d4d1 memory unplug: mi... |
1026 |
*/ |
03f15c86c mm: simplify page... |
1027 |
if (PageAnon(page) && !PageKsm(page)) |
746b18d42 mm: use refcounts... |
1028 |
anon_vma = page_get_anon_vma(page); |
62e1c5530 page migraton: ha... |
1029 |
|
7db7671f8 mm: page migratio... |
1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 |
/* * Block others from accessing the new page when we get around to * establishing additional references. We are usually the only one * holding a reference to newpage at this point. We used to have a BUG * here if trylock_page(newpage) fails, but would like to allow for * cases where there might be a race with the previous use of newpage. * This is much like races on refcount of oldpage: just don't BUG(). */ if (unlikely(!trylock_page(newpage))) goto out_unlock; |
bda807d44 mm: migrate: supp... |
1040 1041 1042 1043 |
if (unlikely(!is_lru)) { rc = move_to_new_page(newpage, page, mode); goto out_unlock_both; } |
dc386d4d1 memory unplug: mi... |
1044 |
/* |
62e1c5530 page migraton: ha... |
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 |
* Corner case handling: * 1. When a new swap-cache page is read into, it is added to the LRU * and treated as swapcache but it has no rmap yet. * Calling try_to_unmap() against a page->mapping==NULL page will * trigger a BUG. So handle it here. * 2. An orphaned page (see truncate_complete_page) might have * fs-private metadata. The page can be picked up due to memory * offlining. Everywhere else except page reclaim, the page is * invisible to the vm, so the page can not be migrated. So try to * free the metadata, so the page can be freed. |
e24f0b8f7 [PATCH] page migr... |
1055 |
*/ |
62e1c5530 page migraton: ha... |
1056 |
if (!page->mapping) { |
309381fea mm: dump page whe... |
1057 |
VM_BUG_ON_PAGE(PageAnon(page), page); |
1ce82b69e mm: fix migration... |
1058 |
if (page_has_private(page)) { |
62e1c5530 page migraton: ha... |
1059 |
try_to_free_buffers(page); |
7db7671f8 mm: page migratio... |
1060 |
goto out_unlock_both; |
62e1c5530 page migraton: ha... |
1061 |
} |
7db7671f8 mm: page migratio... |
1062 1063 |
} else if (page_mapped(page)) { /* Establish migration ptes */ |
03f15c86c mm: simplify page... |
1064 1065 |
VM_BUG_ON_PAGE(PageAnon(page) && !PageKsm(page) && !anon_vma, page); |
2ebba6b7e mm: unmapped page... |
1066 |
try_to_unmap(page, |
da1b13ccf mm/hwpoison: fix ... |
1067 |
TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); |
2ebba6b7e mm: unmapped page... |
1068 1069 |
page_was_mapped = 1; } |
dc386d4d1 memory unplug: mi... |
1070 |
|
e6a1530d6 [PATCH] Allow mig... |
1071 |
if (!page_mapped(page)) |
5c3f9a673 mm: page migratio... |
1072 |
rc = move_to_new_page(newpage, page, mode); |
e24f0b8f7 [PATCH] page migr... |
1073 |
|
5c3f9a673 mm: page migratio... |
1074 1075 |
if (page_was_mapped) remove_migration_ptes(page, |
e388466de mm: make remove_m... |
1076 |
rc == MIGRATEPAGE_SUCCESS ? newpage : page, false); |
3f6c82728 mm: migration: ta... |
1077 |
|
7db7671f8 mm: page migratio... |
1078 1079 1080 |
out_unlock_both: unlock_page(newpage); out_unlock: |
3f6c82728 mm: migration: ta... |
1081 |
/* Drop an anon_vma reference if we took one */ |
76545066c mm: extend KSM re... |
1082 |
if (anon_vma) |
9e60109f1 mm: rename drop_a... |
1083 |
put_anon_vma(anon_vma); |
e24f0b8f7 [PATCH] page migr... |
1084 |
unlock_page(page); |
0dabec93d mm: migration: cl... |
1085 |
out: |
c6c919eb9 mm: use put_page(... |
1086 1087 1088 1089 |
/* * If migration is successful, decrease refcount of the newpage * which will not free the page because new page owner increased * refcounter. As well, if it is LRU page, add the page to LRU |
e0a352fab mm: migrate: don'... |
1090 1091 1092 1093 |
* list in here. Use the old state of the isolated source page to * determine if we migrated a LRU page. newpage was already unlocked * and possibly modified by its owner - don't rely on the page * state. |
c6c919eb9 mm: use put_page(... |
1094 1095 |
*/ if (rc == MIGRATEPAGE_SUCCESS) { |
e0a352fab mm: migrate: don'... |
1096 |
if (unlikely(!is_lru)) |
c6c919eb9 mm: use put_page(... |
1097 1098 1099 1100 |
put_page(newpage); else putback_lru_page(newpage); } |
0dabec93d mm: migration: cl... |
1101 1102 |
return rc; } |
95a402c38 [PATCH] page migr... |
1103 |
|
0dabec93d mm: migration: cl... |
1104 |
/* |
ef2a5153b mm/migrate: mark ... |
1105 1106 1107 |
* gcc 4.7 and 4.8 on arm get an ICEs when inlining unmap_and_move(). Work * around it. */ |
815f0ddb3 include/linux/com... |
1108 1109 |
#if defined(CONFIG_ARM) && \ defined(GCC_VERSION) && GCC_VERSION < 40900 && GCC_VERSION >= 40700 |
ef2a5153b mm/migrate: mark ... |
1110 1111 1112 1113 1114 1115 |
#define ICE_noinline noinline #else #define ICE_noinline #endif /* |
0dabec93d mm: migration: cl... |
1116 1117 1118 |
* Obtain the lock on page, remove all ptes and migrate the page * to the newly allocated page in newpage. */ |
ef2a5153b mm/migrate: mark ... |
1119 1120 1121 |
static ICE_noinline int unmap_and_move(new_page_t get_new_page, free_page_t put_new_page, unsigned long private, struct page *page, |
add05cece mm: soft-offline:... |
1122 1123 |
int force, enum migrate_mode mode, enum migrate_reason reason) |
0dabec93d mm: migration: cl... |
1124 |
{ |
2def7424c mm: page migratio... |
1125 |
int rc = MIGRATEPAGE_SUCCESS; |
2def7424c mm: page migratio... |
1126 |
struct page *newpage; |
0dabec93d mm: migration: cl... |
1127 |
|
94723aafb mm: unclutter THP... |
1128 1129 |
if (!thp_migration_supported() && PageTransHuge(page)) return -ENOMEM; |
666feb21a mm, migrate: remo... |
1130 |
newpage = get_new_page(page, private); |
0dabec93d mm: migration: cl... |
1131 1132 1133 1134 1135 |
if (!newpage) return -ENOMEM; if (page_count(page) == 1) { /* page was freed from under us. So we are done. */ |
c6c919eb9 mm: use put_page(... |
1136 1137 |
ClearPageActive(page); ClearPageUnevictable(page); |
bda807d44 mm: migrate: supp... |
1138 1139 1140 1141 1142 1143 |
if (unlikely(__PageMovable(page))) { lock_page(page); if (!PageMovable(page)) __ClearPageIsolated(page); unlock_page(page); } |
c6c919eb9 mm: use put_page(... |
1144 1145 1146 1147 |
if (put_new_page) put_new_page(newpage, private); else put_page(newpage); |
0dabec93d mm: migration: cl... |
1148 1149 |
goto out; } |
9c620e2bc mm: remove offlin... |
1150 |
rc = __unmap_and_move(page, newpage, force, mode); |
c6c919eb9 mm: use put_page(... |
1151 |
if (rc == MIGRATEPAGE_SUCCESS) |
7cd12b4ab mm, page_owner: t... |
1152 |
set_page_owner_migrate_reason(newpage, reason); |
bf6bddf19 mm: introduce com... |
1153 |
|
0dabec93d mm: migration: cl... |
1154 |
out: |
e24f0b8f7 [PATCH] page migr... |
1155 |
if (rc != -EAGAIN) { |
0dabec93d mm: migration: cl... |
1156 1157 1158 1159 1160 1161 1162 |
/* * A page that has been migrated has all references * removed and will be freed. A page that has not been * migrated will have kepts its references and be * restored. */ list_del(&page->lru); |
6afcf8ef0 mm, compaction: f... |
1163 1164 1165 1166 1167 1168 1169 |
/* * Compaction can migrate also non-LRU pages which are * not accounted to NR_ISOLATED_*. They can be recognized * as __PageMovable */ if (likely(!__PageMovable(page))) |
e8db67eb0 mm: migrate: move... |
1170 1171 |
mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_cache(page), -hpage_nr_pages(page)); |
c6c919eb9 mm: use put_page(... |
1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 |
} /* * If migration is successful, releases reference grabbed during * isolation. Otherwise, restore the page to right list unless * we want to retry. */ if (rc == MIGRATEPAGE_SUCCESS) { put_page(page); if (reason == MR_MEMORY_FAILURE) { |
d7e69488b mm/hwpoison: fix ... |
1182 |
/* |
c6c919eb9 mm: use put_page(... |
1183 1184 1185 |
* Set PG_HWPoison on just freed page * intentionally. Although it's rather weird, * it's how HWPoison flag works at the moment. |
d7e69488b mm/hwpoison: fix ... |
1186 |
*/ |
d4ae9916e mm: soft-offline:... |
1187 |
if (set_hwpoison_free_buddy_page(page)) |
da1b13ccf mm/hwpoison: fix ... |
1188 |
num_poisoned_pages_inc(); |
c6c919eb9 mm: use put_page(... |
1189 1190 |
} } else { |
bda807d44 mm: migrate: supp... |
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 |
if (rc != -EAGAIN) { if (likely(!__PageMovable(page))) { putback_lru_page(page); goto put_new; } lock_page(page); if (PageMovable(page)) putback_movable_page(page); else __ClearPageIsolated(page); unlock_page(page); put_page(page); } put_new: |
c6c919eb9 mm: use put_page(... |
1206 1207 1208 1209 |
if (put_new_page) put_new_page(newpage, private); else put_page(newpage); |
e24f0b8f7 [PATCH] page migr... |
1210 |
} |
68711a746 mm, migration: ad... |
1211 |
|
e24f0b8f7 [PATCH] page migr... |
1212 1213 1214 1215 |
return rc; } /* |
290408d4a hugetlb: hugepage... |
1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 |
* Counterpart of unmap_and_move_page() for hugepage migration. * * This function doesn't wait the completion of hugepage I/O * because there is no race between I/O and migration for hugepage. * Note that currently hugepage I/O occurs only in direct I/O * where no lock is held and PG_writeback is irrelevant, * and writeback status of all subpages are counted in the reference * count of the head page (i.e. if all subpages of a 2MB hugepage are * under direct I/O, the reference of the head page is 512 and a bit more.) * This means that when we try to migrate hugepage whose subpages are * doing direct I/O, some references remain after try_to_unmap() and * hugepage migration fails without data corruption. * * There is also no race when direct I/O is issued on the page under migration, * because then pte is replaced with migration swap entry and direct I/O code * will wait in the page fault for migration to complete. */ static int unmap_and_move_huge_page(new_page_t get_new_page, |
68711a746 mm, migration: ad... |
1234 1235 |
free_page_t put_new_page, unsigned long private, struct page *hpage, int force, |
7cd12b4ab mm, page_owner: t... |
1236 |
enum migrate_mode mode, int reason) |
290408d4a hugetlb: hugepage... |
1237 |
{ |
2def7424c mm: page migratio... |
1238 |
int rc = -EAGAIN; |
2ebba6b7e mm: unmapped page... |
1239 |
int page_was_mapped = 0; |
32665f2bb mm/migrate: corre... |
1240 |
struct page *new_hpage; |
290408d4a hugetlb: hugepage... |
1241 |
struct anon_vma *anon_vma = NULL; |
83467efbd mm: migrate: chec... |
1242 |
/* |
7ed2c31da mm/hugetlb: disti... |
1243 |
* Migratability of hugepages depends on architectures and their size. |
83467efbd mm: migrate: chec... |
1244 1245 1246 1247 1248 |
* This check is necessary because some callers of hugepage migration * like soft offline and memory hotremove don't walk through page * tables or check whether the hugepage is pmd-based or not before * kicking migration. */ |
100873d7a hugetlb: rename h... |
1249 |
if (!hugepage_migration_supported(page_hstate(hpage))) { |
32665f2bb mm/migrate: corre... |
1250 |
putback_active_hugepage(hpage); |
83467efbd mm: migrate: chec... |
1251 |
return -ENOSYS; |
32665f2bb mm/migrate: corre... |
1252 |
} |
83467efbd mm: migrate: chec... |
1253 |
|
666feb21a mm, migrate: remo... |
1254 |
new_hpage = get_new_page(hpage, private); |
290408d4a hugetlb: hugepage... |
1255 1256 |
if (!new_hpage) return -ENOMEM; |
290408d4a hugetlb: hugepage... |
1257 |
if (!trylock_page(hpage)) { |
2916ecc0f mm/migrate: new m... |
1258 |
if (!force) |
290408d4a hugetlb: hugepage... |
1259 |
goto out; |
2916ecc0f mm/migrate: new m... |
1260 1261 1262 1263 1264 1265 1266 |
switch (mode) { case MIGRATE_SYNC: case MIGRATE_SYNC_NO_COPY: break; default: goto out; } |
290408d4a hugetlb: hugepage... |
1267 1268 |
lock_page(hpage); } |
cb6acd01e hugetlbfs: fix ra... |
1269 1270 1271 1272 1273 1274 1275 1276 1277 |
/* * Check for pages which are in the process of being freed. Without * page_mapping() set, hugetlbfs specific move page routine will not * be called and we could leak usage counts for subpools. */ if (page_private(hpage) && !page_mapping(hpage)) { rc = -EBUSY; goto out_unlock; } |
746b18d42 mm: use refcounts... |
1278 1279 |
if (PageAnon(hpage)) anon_vma = page_get_anon_vma(hpage); |
290408d4a hugetlb: hugepage... |
1280 |
|
7db7671f8 mm: page migratio... |
1281 1282 |
if (unlikely(!trylock_page(new_hpage))) goto put_anon; |
2ebba6b7e mm: unmapped page... |
1283 1284 |
if (page_mapped(hpage)) { try_to_unmap(hpage, |
ddeaab32a hugetlbfs: revert... |
1285 |
TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); |
2ebba6b7e mm: unmapped page... |
1286 1287 |
page_was_mapped = 1; } |
290408d4a hugetlb: hugepage... |
1288 1289 |
if (!page_mapped(hpage)) |
5c3f9a673 mm: page migratio... |
1290 |
rc = move_to_new_page(new_hpage, hpage, mode); |
290408d4a hugetlb: hugepage... |
1291 |
|
5c3f9a673 mm: page migratio... |
1292 1293 |
if (page_was_mapped) remove_migration_ptes(hpage, |
e388466de mm: make remove_m... |
1294 |
rc == MIGRATEPAGE_SUCCESS ? new_hpage : hpage, false); |
290408d4a hugetlb: hugepage... |
1295 |
|
7db7671f8 mm: page migratio... |
1296 1297 1298 |
unlock_page(new_hpage); put_anon: |
fd4a4663d mm: fix hugepage ... |
1299 |
if (anon_vma) |
9e60109f1 mm: rename drop_a... |
1300 |
put_anon_vma(anon_vma); |
8e6ac7fab hugetlb/cgroup: m... |
1301 |
|
2def7424c mm: page migratio... |
1302 |
if (rc == MIGRATEPAGE_SUCCESS) { |
ab5ac90ae mm, hugetlb: do n... |
1303 |
move_hugetlb_state(hpage, new_hpage, reason); |
2def7424c mm: page migratio... |
1304 1305 |
put_new_page = NULL; } |
8e6ac7fab hugetlb/cgroup: m... |
1306 |
|
cb6acd01e hugetlbfs: fix ra... |
1307 |
out_unlock: |
290408d4a hugetlb: hugepage... |
1308 |
unlock_page(hpage); |
09761333e mm/migrate.c: pai... |
1309 |
out: |
b8ec1cee5 mm: soft-offline:... |
1310 1311 |
if (rc != -EAGAIN) putback_active_hugepage(hpage); |
68711a746 mm, migration: ad... |
1312 1313 1314 1315 1316 1317 |
/* * If migration was not successful and there's a freeing callback, use * it. Otherwise, put_page() will drop the reference grabbed during * isolation. */ |
2def7424c mm: page migratio... |
1318 |
if (put_new_page) |
68711a746 mm, migration: ad... |
1319 1320 |
put_new_page(new_hpage, private); else |
3aaa76e12 mm: migrate: huge... |
1321 |
putback_active_hugepage(new_hpage); |
68711a746 mm, migration: ad... |
1322 |
|
290408d4a hugetlb: hugepage... |
1323 1324 1325 1326 |
return rc; } /* |
c73e5c9c5 mm: rewrite the c... |
1327 1328 |
* migrate_pages - migrate the pages specified in a list, to the free pages * supplied as the target for the page migration |
b20a35035 [PATCH] page migr... |
1329 |
* |
c73e5c9c5 mm: rewrite the c... |
1330 1331 1332 |
* @from: The list of pages to be migrated. * @get_new_page: The function used to allocate free pages to be used * as the target of the page migration. |
68711a746 mm, migration: ad... |
1333 1334 |
* @put_new_page: The function used to free target pages if migration * fails, or NULL if no special handling is necessary. |
c73e5c9c5 mm: rewrite the c... |
1335 1336 1337 1338 |
* @private: Private data to be passed on to get_new_page() * @mode: The migration mode that specifies the constraints for * page migration, if any. * @reason: The reason for page migration. |
b20a35035 [PATCH] page migr... |
1339 |
* |
c73e5c9c5 mm: rewrite the c... |
1340 1341 |
* The function returns after 10 attempts or if no pages are movable any more * because the list has become empty or no retryable pages exist any more. |
14e0f9bcc mm: correct a cou... |
1342 |
* The caller should call putback_movable_pages() to return pages to the LRU |
28bd65781 mm: migration: cl... |
1343 |
* or free list only if ret != 0. |
b20a35035 [PATCH] page migr... |
1344 |
* |
c73e5c9c5 mm: rewrite the c... |
1345 |
* Returns the number of pages that were not migrated, or an error code. |
b20a35035 [PATCH] page migr... |
1346 |
*/ |
9c620e2bc mm: remove offlin... |
1347 |
int migrate_pages(struct list_head *from, new_page_t get_new_page, |
68711a746 mm, migration: ad... |
1348 1349 |
free_page_t put_new_page, unsigned long private, enum migrate_mode mode, int reason) |
b20a35035 [PATCH] page migr... |
1350 |
{ |
e24f0b8f7 [PATCH] page migr... |
1351 |
int retry = 1; |
b20a35035 [PATCH] page migr... |
1352 |
int nr_failed = 0; |
5647bc293 mm: compaction: M... |
1353 |
int nr_succeeded = 0; |
b20a35035 [PATCH] page migr... |
1354 1355 1356 1357 1358 1359 1360 1361 |
int pass = 0; struct page *page; struct page *page2; int swapwrite = current->flags & PF_SWAPWRITE; int rc; if (!swapwrite) current->flags |= PF_SWAPWRITE; |
e24f0b8f7 [PATCH] page migr... |
1362 1363 |
for(pass = 0; pass < 10 && retry; pass++) { retry = 0; |
b20a35035 [PATCH] page migr... |
1364 |
|
e24f0b8f7 [PATCH] page migr... |
1365 |
list_for_each_entry_safe(page, page2, from, lru) { |
94723aafb mm: unclutter THP... |
1366 |
retry: |
e24f0b8f7 [PATCH] page migr... |
1367 |
cond_resched(); |
2d1db3b11 [PATCH] page migr... |
1368 |
|
31caf665e mm: migrate: make... |
1369 1370 |
if (PageHuge(page)) rc = unmap_and_move_huge_page(get_new_page, |
68711a746 mm, migration: ad... |
1371 |
put_new_page, private, page, |
7cd12b4ab mm, page_owner: t... |
1372 |
pass > 2, mode, reason); |
31caf665e mm: migrate: make... |
1373 |
else |
68711a746 mm, migration: ad... |
1374 |
rc = unmap_and_move(get_new_page, put_new_page, |
add05cece mm: soft-offline:... |
1375 1376 |
private, page, pass > 2, mode, reason); |
2d1db3b11 [PATCH] page migr... |
1377 |
|
e24f0b8f7 [PATCH] page migr... |
1378 |
switch(rc) { |
95a402c38 [PATCH] page migr... |
1379 |
case -ENOMEM: |
94723aafb mm: unclutter THP... |
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 |
/* * THP migration might be unsupported or the * allocation could've failed so we should * retry on the same page with the THP split * to base pages. * * Head page is retried immediately and tail * pages are added to the tail of the list so * we encounter them after the rest of the list * is processed. */ |
e6112fc30 mm/migrate.c: spl... |
1391 |
if (PageTransHuge(page) && !PageHuge(page)) { |
94723aafb mm: unclutter THP... |
1392 1393 1394 1395 1396 1397 1398 1399 |
lock_page(page); rc = split_huge_page_to_list(page, from); unlock_page(page); if (!rc) { list_safe_reset_next(page, page2, lru); goto retry; } } |
dfef2ef40 mm, migrate: incr... |
1400 |
nr_failed++; |
95a402c38 [PATCH] page migr... |
1401 |
goto out; |
e24f0b8f7 [PATCH] page migr... |
1402 |
case -EAGAIN: |
2d1db3b11 [PATCH] page migr... |
1403 |
retry++; |
e24f0b8f7 [PATCH] page migr... |
1404 |
break; |
78bd52097 mm: adjust addres... |
1405 |
case MIGRATEPAGE_SUCCESS: |
5647bc293 mm: compaction: M... |
1406 |
nr_succeeded++; |
e24f0b8f7 [PATCH] page migr... |
1407 1408 |
break; default: |
354a33633 mm/migrate: add c... |
1409 1410 1411 1412 1413 1414 |
/* * Permanent failure (-EBUSY, -ENOSYS, etc.): * unlike -EAGAIN case, the failed page is * removed from migration page list and not * retried in the next outer loop. */ |
2d1db3b11 [PATCH] page migr... |
1415 |
nr_failed++; |
e24f0b8f7 [PATCH] page migr... |
1416 |
break; |
2d1db3b11 [PATCH] page migr... |
1417 |
} |
b20a35035 [PATCH] page migr... |
1418 1419 |
} } |
f2f81fb2b mm, migrate: coun... |
1420 1421 |
nr_failed += retry; rc = nr_failed; |
95a402c38 [PATCH] page migr... |
1422 |
out: |
5647bc293 mm: compaction: M... |
1423 1424 1425 1426 |
if (nr_succeeded) count_vm_events(PGMIGRATE_SUCCESS, nr_succeeded); if (nr_failed) count_vm_events(PGMIGRATE_FAIL, nr_failed); |
7b2a2d4a1 mm: migrate: Add ... |
1427 |
trace_mm_migrate_pages(nr_succeeded, nr_failed, mode, reason); |
b20a35035 [PATCH] page migr... |
1428 1429 |
if (!swapwrite) current->flags &= ~PF_SWAPWRITE; |
78bd52097 mm: adjust addres... |
1430 |
return rc; |
b20a35035 [PATCH] page migr... |
1431 |
} |
95a402c38 [PATCH] page migr... |
1432 |
|
742755a1d [PATCH] page migr... |
1433 |
#ifdef CONFIG_NUMA |
742755a1d [PATCH] page migr... |
1434 |
|
a49bd4d71 mm, numa: rework ... |
1435 |
static int store_status(int __user *status, int start, int value, int nr) |
742755a1d [PATCH] page migr... |
1436 |
{ |
a49bd4d71 mm, numa: rework ... |
1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 |
while (nr-- > 0) { if (put_user(value, status + start)) return -EFAULT; start++; } return 0; } static int do_move_pages_to_node(struct mm_struct *mm, struct list_head *pagelist, int node) { int err; if (list_empty(pagelist)) return 0; err = migrate_pages(pagelist, alloc_new_node_page, NULL, node, MIGRATE_SYNC, MR_SYSCALL); if (err) putback_movable_pages(pagelist); return err; |
742755a1d [PATCH] page migr... |
1459 1460 1461 |
} /* |
a49bd4d71 mm, numa: rework ... |
1462 1463 1464 1465 1466 |
* Resolves the given address to a struct page, isolates it from the LRU and * puts it to the given pagelist. * Returns -errno if the page cannot be found/isolated or 0 when it has been * queued or the page doesn't need to be migrated because it is already on * the target node |
742755a1d [PATCH] page migr... |
1467 |
*/ |
a49bd4d71 mm, numa: rework ... |
1468 1469 |
static int add_page_for_migration(struct mm_struct *mm, unsigned long addr, int node, struct list_head *pagelist, bool migrate_all) |
742755a1d [PATCH] page migr... |
1470 |
{ |
a49bd4d71 mm, numa: rework ... |
1471 1472 1473 |
struct vm_area_struct *vma; struct page *page; unsigned int follflags; |
742755a1d [PATCH] page migr... |
1474 |
int err; |
742755a1d [PATCH] page migr... |
1475 1476 |
down_read(&mm->mmap_sem); |
a49bd4d71 mm, numa: rework ... |
1477 1478 1479 1480 |
err = -EFAULT; vma = find_vma(mm, addr); if (!vma || addr < vma->vm_start || !vma_migratable(vma)) goto out; |
742755a1d [PATCH] page migr... |
1481 |
|
a49bd4d71 mm, numa: rework ... |
1482 1483 |
/* FOLL_DUMP to ignore special (like zero) pages */ follflags = FOLL_GET | FOLL_DUMP; |
a49bd4d71 mm, numa: rework ... |
1484 |
page = follow_page(vma, addr, follflags); |
89f5b7da2 Reinstate ZERO_PA... |
1485 |
|
a49bd4d71 mm, numa: rework ... |
1486 1487 1488 |
err = PTR_ERR(page); if (IS_ERR(page)) goto out; |
89f5b7da2 Reinstate ZERO_PA... |
1489 |
|
a49bd4d71 mm, numa: rework ... |
1490 1491 1492 |
err = -ENOENT; if (!page) goto out; |
742755a1d [PATCH] page migr... |
1493 |
|
a49bd4d71 mm, numa: rework ... |
1494 1495 1496 |
err = 0; if (page_to_nid(page) == node) goto out_putpage; |
742755a1d [PATCH] page migr... |
1497 |
|
a49bd4d71 mm, numa: rework ... |
1498 1499 1500 |
err = -EACCES; if (page_mapcount(page) > 1 && !migrate_all) goto out_putpage; |
742755a1d [PATCH] page migr... |
1501 |
|
a49bd4d71 mm, numa: rework ... |
1502 1503 1504 1505 |
if (PageHuge(page)) { if (PageHead(page)) { isolate_huge_page(page, pagelist); err = 0; |
e632a938d mm: migrate: add ... |
1506 |
} |
a49bd4d71 mm, numa: rework ... |
1507 1508 |
} else { struct page *head; |
e632a938d mm: migrate: add ... |
1509 |
|
e8db67eb0 mm: migrate: move... |
1510 1511 |
head = compound_head(page); err = isolate_lru_page(head); |
cf608ac19 mm: compaction: f... |
1512 |
if (err) |
a49bd4d71 mm, numa: rework ... |
1513 |
goto out_putpage; |
742755a1d [PATCH] page migr... |
1514 |
|
a49bd4d71 mm, numa: rework ... |
1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 |
err = 0; list_add_tail(&head->lru, pagelist); mod_node_page_state(page_pgdat(head), NR_ISOLATED_ANON + page_is_file_cache(head), hpage_nr_pages(head)); } out_putpage: /* * Either remove the duplicate refcount from * isolate_lru_page() or drop the page ref if it was * not isolated. */ put_page(page); out: |
742755a1d [PATCH] page migr... |
1529 1530 1531 1532 1533 |
up_read(&mm->mmap_sem); return err; } /* |
5e9a0f023 mm: extract do_pa... |
1534 1535 1536 |
* Migrate an array of page address onto an array of nodes and fill * the corresponding array of status. */ |
3268c63ed mm: fix move/migr... |
1537 |
static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, |
5e9a0f023 mm: extract do_pa... |
1538 1539 1540 1541 1542 |
unsigned long nr_pages, const void __user * __user *pages, const int __user *nodes, int __user *status, int flags) { |
a49bd4d71 mm, numa: rework ... |
1543 1544 1545 1546 |
int current_node = NUMA_NO_NODE; LIST_HEAD(pagelist); int start, i; int err = 0, err1; |
35282a2de migration: only m... |
1547 1548 |
migrate_prep(); |
a49bd4d71 mm, numa: rework ... |
1549 1550 1551 1552 |
for (i = start = 0; i < nr_pages; i++) { const void __user *p; unsigned long addr; int node; |
3140a2273 mm: rework do_pag... |
1553 |
|
a49bd4d71 mm, numa: rework ... |
1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 |
err = -EFAULT; if (get_user(p, pages + i)) goto out_flush; if (get_user(node, nodes + i)) goto out_flush; addr = (unsigned long)p; err = -ENODEV; if (node < 0 || node >= MAX_NUMNODES) goto out_flush; if (!node_state(node, N_MEMORY)) goto out_flush; |
5e9a0f023 mm: extract do_pa... |
1566 |
|
a49bd4d71 mm, numa: rework ... |
1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 |
err = -EACCES; if (!node_isset(node, task_nodes)) goto out_flush; if (current_node == NUMA_NO_NODE) { current_node = node; start = i; } else if (node != current_node) { err = do_move_pages_to_node(mm, &pagelist, current_node); if (err) goto out; err = store_status(status, start, current_node, i - start); if (err) goto out; start = i; current_node = node; |
3140a2273 mm: rework do_pag... |
1583 |
} |
a49bd4d71 mm, numa: rework ... |
1584 1585 1586 1587 1588 1589 1590 1591 |
/* * Errors in the page lookup or isolation are not fatal and we simply * report them via status */ err = add_page_for_migration(mm, addr, current_node, &pagelist, flags & MPOL_MF_MOVE_ALL); if (!err) continue; |
3140a2273 mm: rework do_pag... |
1592 |
|
a49bd4d71 mm, numa: rework ... |
1593 1594 1595 |
err = store_status(status, i, err, 1); if (err) goto out_flush; |
5e9a0f023 mm: extract do_pa... |
1596 |
|
a49bd4d71 mm, numa: rework ... |
1597 1598 1599 1600 1601 1602 1603 1604 1605 |
err = do_move_pages_to_node(mm, &pagelist, current_node); if (err) goto out; if (i > start) { err = store_status(status, start, current_node, i - start); if (err) goto out; } current_node = NUMA_NO_NODE; |
3140a2273 mm: rework do_pag... |
1606 |
} |
a49bd4d71 mm, numa: rework ... |
1607 |
out_flush: |
8f175cf5c mm: fix do_pages_... |
1608 1609 |
if (list_empty(&pagelist)) return err; |
a49bd4d71 mm, numa: rework ... |
1610 1611 1612 1613 1614 1615 |
/* Make sure we do not overwrite the existing error */ err1 = do_move_pages_to_node(mm, &pagelist, current_node); if (!err1) err1 = store_status(status, start, current_node, i - start); if (!err) err = err1; |
5e9a0f023 mm: extract do_pa... |
1616 1617 1618 1619 1620 |
out: return err; } /* |
2f007e74b mm: don't vmalloc... |
1621 |
* Determine the nodes of an array of pages and store it in an array of status. |
742755a1d [PATCH] page migr... |
1622 |
*/ |
80bba1290 mm: no get_user/p... |
1623 1624 |
static void do_pages_stat_array(struct mm_struct *mm, unsigned long nr_pages, const void __user **pages, int *status) |
742755a1d [PATCH] page migr... |
1625 |
{ |
2f007e74b mm: don't vmalloc... |
1626 |
unsigned long i; |
2f007e74b mm: don't vmalloc... |
1627 |
|
742755a1d [PATCH] page migr... |
1628 |
down_read(&mm->mmap_sem); |
2f007e74b mm: don't vmalloc... |
1629 |
for (i = 0; i < nr_pages; i++) { |
80bba1290 mm: no get_user/p... |
1630 |
unsigned long addr = (unsigned long)(*pages); |
742755a1d [PATCH] page migr... |
1631 1632 |
struct vm_area_struct *vma; struct page *page; |
c095adbc2 mm: Don't touch u... |
1633 |
int err = -EFAULT; |
2f007e74b mm: don't vmalloc... |
1634 1635 |
vma = find_vma(mm, addr); |
70384dc6d mm: fix error rep... |
1636 |
if (!vma || addr < vma->vm_start) |
742755a1d [PATCH] page migr... |
1637 |
goto set_status; |
d899844e9 mm: fix status co... |
1638 1639 |
/* FOLL_DUMP to ignore special (like zero) pages */ page = follow_page(vma, addr, FOLL_DUMP); |
89f5b7da2 Reinstate ZERO_PA... |
1640 1641 1642 1643 |
err = PTR_ERR(page); if (IS_ERR(page)) goto set_status; |
d899844e9 mm: fix status co... |
1644 |
err = page ? page_to_nid(page) : -ENOENT; |
742755a1d [PATCH] page migr... |
1645 |
set_status: |
80bba1290 mm: no get_user/p... |
1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 |
*status = err; pages++; status++; } up_read(&mm->mmap_sem); } /* * Determine the nodes of a user array of pages and store it in * a user array of status. */ static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages, const void __user * __user *pages, int __user *status) { #define DO_PAGES_STAT_CHUNK_NR 16 const void __user *chunk_pages[DO_PAGES_STAT_CHUNK_NR]; int chunk_status[DO_PAGES_STAT_CHUNK_NR]; |
80bba1290 mm: no get_user/p... |
1666 |
|
87b8d1ade mm: Make copy_fro... |
1667 1668 |
while (nr_pages) { unsigned long chunk_nr; |
80bba1290 mm: no get_user/p... |
1669 |
|
87b8d1ade mm: Make copy_fro... |
1670 1671 1672 1673 1674 1675 |
chunk_nr = nr_pages; if (chunk_nr > DO_PAGES_STAT_CHUNK_NR) chunk_nr = DO_PAGES_STAT_CHUNK_NR; if (copy_from_user(chunk_pages, pages, chunk_nr * sizeof(*chunk_pages))) break; |
80bba1290 mm: no get_user/p... |
1676 1677 |
do_pages_stat_array(mm, chunk_nr, chunk_pages, chunk_status); |
87b8d1ade mm: Make copy_fro... |
1678 1679 |
if (copy_to_user(status, chunk_status, chunk_nr * sizeof(*status))) break; |
742755a1d [PATCH] page migr... |
1680 |
|
87b8d1ade mm: Make copy_fro... |
1681 1682 1683 1684 1685 |
pages += chunk_nr; status += chunk_nr; nr_pages -= chunk_nr; } return nr_pages ? -EFAULT : 0; |
742755a1d [PATCH] page migr... |
1686 1687 1688 1689 1690 1691 |
} /* * Move a list of pages in the address space of the currently executing * process. */ |
7addf4438 mm: add kernel_mo... |
1692 1693 1694 1695 |
static int kernel_move_pages(pid_t pid, unsigned long nr_pages, const void __user * __user *pages, const int __user *nodes, int __user *status, int flags) |
742755a1d [PATCH] page migr... |
1696 |
{ |
742755a1d [PATCH] page migr... |
1697 |
struct task_struct *task; |
742755a1d [PATCH] page migr... |
1698 |
struct mm_struct *mm; |
5e9a0f023 mm: extract do_pa... |
1699 |
int err; |
3268c63ed mm: fix move/migr... |
1700 |
nodemask_t task_nodes; |
742755a1d [PATCH] page migr... |
1701 1702 1703 1704 1705 1706 1707 1708 1709 |
/* Check flags */ if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL)) return -EINVAL; if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) return -EPERM; /* Find the mm_struct */ |
a879bf582 mm: grab rcu read... |
1710 |
rcu_read_lock(); |
228ebcbe6 Uninline find_tas... |
1711 |
task = pid ? find_task_by_vpid(pid) : current; |
742755a1d [PATCH] page migr... |
1712 |
if (!task) { |
a879bf582 mm: grab rcu read... |
1713 |
rcu_read_unlock(); |
742755a1d [PATCH] page migr... |
1714 1715 |
return -ESRCH; } |
3268c63ed mm: fix move/migr... |
1716 |
get_task_struct(task); |
742755a1d [PATCH] page migr... |
1717 1718 1719 |
/* * Check if this process has the right to modify the specified |
197e7e521 Sanitize 'move_pa... |
1720 |
* process. Use the regular "ptrace_may_access()" checks. |
742755a1d [PATCH] page migr... |
1721 |
*/ |
197e7e521 Sanitize 'move_pa... |
1722 |
if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) { |
c69e8d9c0 CRED: Use RCU to ... |
1723 |
rcu_read_unlock(); |
742755a1d [PATCH] page migr... |
1724 |
err = -EPERM; |
5e9a0f023 mm: extract do_pa... |
1725 |
goto out; |
742755a1d [PATCH] page migr... |
1726 |
} |
c69e8d9c0 CRED: Use RCU to ... |
1727 |
rcu_read_unlock(); |
742755a1d [PATCH] page migr... |
1728 |
|
86c3a7645 [PATCH] SELinux: ... |
1729 1730 |
err = security_task_movememory(task); if (err) |
5e9a0f023 mm: extract do_pa... |
1731 |
goto out; |
86c3a7645 [PATCH] SELinux: ... |
1732 |
|
3268c63ed mm: fix move/migr... |
1733 1734 1735 |
task_nodes = cpuset_mems_allowed(task); mm = get_task_mm(task); put_task_struct(task); |
6e8b09eaf mm: fix NULL ptr ... |
1736 1737 1738 1739 1740 1741 1742 1743 |
if (!mm) return -EINVAL; if (nodes) err = do_pages_move(mm, task_nodes, nr_pages, pages, nodes, status, flags); else err = do_pages_stat(mm, nr_pages, pages, status); |
742755a1d [PATCH] page migr... |
1744 |
|
742755a1d [PATCH] page migr... |
1745 1746 |
mmput(mm); return err; |
3268c63ed mm: fix move/migr... |
1747 1748 1749 1750 |
out: put_task_struct(task); return err; |
742755a1d [PATCH] page migr... |
1751 |
} |
742755a1d [PATCH] page migr... |
1752 |
|
7addf4438 mm: add kernel_mo... |
1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 |
SYSCALL_DEFINE6(move_pages, pid_t, pid, unsigned long, nr_pages, const void __user * __user *, pages, const int __user *, nodes, int __user *, status, int, flags) { return kernel_move_pages(pid, nr_pages, pages, nodes, status, flags); } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages, compat_uptr_t __user *, pages32, const int __user *, nodes, int __user *, status, int, flags) { const void __user * __user *pages; int i; pages = compat_alloc_user_space(nr_pages * sizeof(void *)); for (i = 0; i < nr_pages; i++) { compat_uptr_t p; if (get_user(p, pages32 + i) || put_user(compat_ptr(p), pages + i)) return -EFAULT; } return kernel_move_pages(pid, nr_pages, pages, nodes, status, flags); } #endif /* CONFIG_COMPAT */ |
7039e1dbe mm: migrate: Intr... |
1782 1783 1784 1785 1786 1787 |
#ifdef CONFIG_NUMA_BALANCING /* * Returns true if this is a safe migration target node for misplaced NUMA * pages. Currently it only checks the watermarks which crude */ static bool migrate_balanced_pgdat(struct pglist_data *pgdat, |
3abef4e6c mm: numa: take TH... |
1788 |
unsigned long nr_migrate_pages) |
7039e1dbe mm: migrate: Intr... |
1789 1790 |
{ int z; |
599d0c954 mm, vmscan: move ... |
1791 |
|
7039e1dbe mm: migrate: Intr... |
1792 1793 1794 1795 1796 |
for (z = pgdat->nr_zones - 1; z >= 0; z--) { struct zone *zone = pgdat->node_zones + z; if (!populated_zone(zone)) continue; |
7039e1dbe mm: migrate: Intr... |
1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 |
/* Avoid waking kswapd by allocating pages_to_migrate pages. */ if (!zone_watermark_ok(zone, 0, high_wmark_pages(zone) + nr_migrate_pages, 0, 0)) continue; return true; } return false; } static struct page *alloc_misplaced_dst_page(struct page *page, |
666feb21a mm, migrate: remo... |
1809 |
unsigned long data) |
7039e1dbe mm: migrate: Intr... |
1810 1811 1812 |
{ int nid = (int) data; struct page *newpage; |
96db800f5 mm: rename alloc_... |
1813 |
newpage = __alloc_pages_node(nid, |
e97ca8e5b mm: fix GFP_THISN... |
1814 1815 1816 |
(GFP_HIGHUSER_MOVABLE | __GFP_THISNODE | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN) & |
8479eba77 mm: numa: quickly... |
1817 |
~__GFP_RECLAIM, 0); |
bac0382c6 mm: numa: migrate... |
1818 |
|
7039e1dbe mm: migrate: Intr... |
1819 1820 |
return newpage; } |
1c30e0177 mm: numa: make NU... |
1821 |
static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) |
b32967ff1 mm: numa: Add THP... |
1822 |
{ |
340ef3902 mm: numa: cleanup... |
1823 |
int page_lru; |
a8f607721 mm: numa: Rate li... |
1824 |
|
309381fea mm: dump page whe... |
1825 |
VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page); |
3abef4e6c mm: numa: take TH... |
1826 |
|
7039e1dbe mm: migrate: Intr... |
1827 |
/* Avoid migrating to a node that is nearly full */ |
340ef3902 mm: numa: cleanup... |
1828 1829 |
if (!migrate_balanced_pgdat(pgdat, 1UL << compound_order(page))) return 0; |
7039e1dbe mm: migrate: Intr... |
1830 |
|
340ef3902 mm: numa: cleanup... |
1831 1832 |
if (isolate_lru_page(page)) return 0; |
7039e1dbe mm: migrate: Intr... |
1833 |
|
340ef3902 mm: numa: cleanup... |
1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 |
/* * migrate_misplaced_transhuge_page() skips page migration's usual * check on page_count(), so we must do it here, now that the page * has been isolated: a GUP pin, or any other pin, prevents migration. * The expected page count is 3: 1 for page's mapcount and 1 for the * caller's pin and 1 for the reference taken by isolate_lru_page(). */ if (PageTransHuge(page) && page_count(page) != 3) { putback_lru_page(page); return 0; |
7039e1dbe mm: migrate: Intr... |
1844 |
} |
340ef3902 mm: numa: cleanup... |
1845 |
page_lru = page_is_file_cache(page); |
599d0c954 mm, vmscan: move ... |
1846 |
mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_lru, |
340ef3902 mm: numa: cleanup... |
1847 |
hpage_nr_pages(page)); |
149c33e1c mm: migrate: Drop... |
1848 |
/* |
340ef3902 mm: numa: cleanup... |
1849 1850 1851 |
* Isolating the page has taken another reference, so the * caller's reference can be safely dropped without the page * disappearing underneath us during migration. |
149c33e1c mm: migrate: Drop... |
1852 1853 |
*/ put_page(page); |
340ef3902 mm: numa: cleanup... |
1854 |
return 1; |
b32967ff1 mm: numa: Add THP... |
1855 |
} |
de466bd62 mm: numa: avoid u... |
1856 1857 1858 1859 1860 |
bool pmd_trans_migrating(pmd_t pmd) { struct page *page = pmd_page(pmd); return PageLocked(page); } |
b32967ff1 mm: numa: Add THP... |
1861 1862 1863 1864 1865 |
/* * Attempt to migrate a misplaced page to the specified destination * node. Caller is expected to have an elevated reference count on * the page that will be dropped by this function before returning. */ |
1bc115d87 mm: numa: Scan pa... |
1866 1867 |
int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, int node) |
b32967ff1 mm: numa: Add THP... |
1868 1869 |
{ pg_data_t *pgdat = NODE_DATA(node); |
340ef3902 mm: numa: cleanup... |
1870 |
int isolated; |
b32967ff1 mm: numa: Add THP... |
1871 1872 1873 1874 |
int nr_remaining; LIST_HEAD(migratepages); /* |
1bc115d87 mm: numa: Scan pa... |
1875 1876 |
* Don't migrate file pages that are mapped in multiple processes * with execute permissions as they are probably shared libraries. |
b32967ff1 mm: numa: Add THP... |
1877 |
*/ |
1bc115d87 mm: numa: Scan pa... |
1878 1879 |
if (page_mapcount(page) != 1 && page_is_file_cache(page) && (vma->vm_flags & VM_EXEC)) |
b32967ff1 mm: numa: Add THP... |
1880 |
goto out; |
b32967ff1 mm: numa: Add THP... |
1881 1882 |
/* |
09a913a7a sched/numa: avoid... |
1883 1884 1885 1886 1887 |
* Also do not migrate dirty pages as not all filesystems can move * dirty pages in MIGRATE_ASYNC mode which is a waste of cycles. */ if (page_is_file_cache(page) && PageDirty(page)) goto out; |
b32967ff1 mm: numa: Add THP... |
1888 1889 1890 1891 1892 |
isolated = numamigrate_isolate_page(pgdat, page); if (!isolated) goto out; list_add(&page->lru, &migratepages); |
9c620e2bc mm: remove offlin... |
1893 |
nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page, |
68711a746 mm, migration: ad... |
1894 1895 |
NULL, node, MIGRATE_ASYNC, MR_NUMA_MISPLACED); |
b32967ff1 mm: numa: Add THP... |
1896 |
if (nr_remaining) { |
59c82b70d mm/migrate: remov... |
1897 1898 |
if (!list_empty(&migratepages)) { list_del(&page->lru); |
599d0c954 mm, vmscan: move ... |
1899 |
dec_node_page_state(page, NR_ISOLATED_ANON + |
59c82b70d mm/migrate: remov... |
1900 1901 1902 |
page_is_file_cache(page)); putback_lru_page(page); } |
b32967ff1 mm: numa: Add THP... |
1903 1904 1905 |
isolated = 0; } else count_vm_numa_event(NUMA_PAGE_MIGRATE); |
7039e1dbe mm: migrate: Intr... |
1906 |
BUG_ON(!list_empty(&migratepages)); |
7039e1dbe mm: migrate: Intr... |
1907 |
return isolated; |
340ef3902 mm: numa: cleanup... |
1908 1909 1910 1911 |
out: put_page(page); return 0; |
7039e1dbe mm: migrate: Intr... |
1912 |
} |
220018d38 mm: numa: Add THP... |
1913 |
#endif /* CONFIG_NUMA_BALANCING */ |
b32967ff1 mm: numa: Add THP... |
1914 |
|
220018d38 mm: numa: Add THP... |
1915 |
#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE) |
340ef3902 mm: numa: cleanup... |
1916 1917 1918 1919 |
/* * Migrates a THP to a given target node. page must be locked and is unlocked * before returning. */ |
b32967ff1 mm: numa: Add THP... |
1920 1921 1922 1923 1924 1925 |
int migrate_misplaced_transhuge_page(struct mm_struct *mm, struct vm_area_struct *vma, pmd_t *pmd, pmd_t entry, unsigned long address, struct page *page, int node) { |
c4088ebdc mm: convert the r... |
1926 |
spinlock_t *ptl; |
b32967ff1 mm: numa: Add THP... |
1927 1928 1929 |
pg_data_t *pgdat = NODE_DATA(node); int isolated = 0; struct page *new_page = NULL; |
b32967ff1 mm: numa: Add THP... |
1930 |
int page_lru = page_is_file_cache(page); |
7066f0f93 mm: thp: fix mmu_... |
1931 |
unsigned long start = address & HPAGE_PMD_MASK; |
b32967ff1 mm: numa: Add THP... |
1932 |
|
b32967ff1 mm: numa: Add THP... |
1933 |
new_page = alloc_pages_node(node, |
251603549 mm, thp: remove _... |
1934 |
(GFP_TRANSHUGE_LIGHT | __GFP_THISNODE), |
e97ca8e5b mm: fix GFP_THISN... |
1935 |
HPAGE_PMD_ORDER); |
340ef3902 mm: numa: cleanup... |
1936 1937 |
if (!new_page) goto out_fail; |
9a982250f thp: introduce de... |
1938 |
prep_transhuge_page(new_page); |
340ef3902 mm: numa: cleanup... |
1939 |
|
b32967ff1 mm: numa: Add THP... |
1940 |
isolated = numamigrate_isolate_page(pgdat, page); |
340ef3902 mm: numa: cleanup... |
1941 |
if (!isolated) { |
b32967ff1 mm: numa: Add THP... |
1942 |
put_page(new_page); |
340ef3902 mm: numa: cleanup... |
1943 |
goto out_fail; |
b32967ff1 mm: numa: Add THP... |
1944 |
} |
b0943d61b mm: numa: defer T... |
1945 |
|
b32967ff1 mm: numa: Add THP... |
1946 |
/* Prepare a page as a migration target */ |
48c935ad8 page-flags: defin... |
1947 |
__SetPageLocked(new_page); |
d44d363f6 mm: don't assume ... |
1948 1949 |
if (PageSwapBacked(page)) __SetPageSwapBacked(new_page); |
b32967ff1 mm: numa: Add THP... |
1950 1951 1952 1953 |
/* anon mapping, we can simply copy page->mapping to the new page: */ new_page->mapping = page->mapping; new_page->index = page->index; |
7eef5f97c mm: thp: relocate... |
1954 1955 |
/* flush the cache before copying using the kernel virtual address */ flush_cache_range(vma, start, start + HPAGE_PMD_SIZE); |
b32967ff1 mm: numa: Add THP... |
1956 1957 1958 1959 |
migrate_page_copy(new_page, page); WARN_ON(PageLRU(new_page)); /* Recheck the target PMD */ |
c4088ebdc mm: convert the r... |
1960 |
ptl = pmd_lock(mm, pmd); |
f4e177d12 mm/migrate.c: sta... |
1961 |
if (unlikely(!pmd_same(*pmd, entry) || !page_ref_freeze(page, 2))) { |
c4088ebdc mm: convert the r... |
1962 |
spin_unlock(ptl); |
b32967ff1 mm: numa: Add THP... |
1963 1964 1965 1966 1967 1968 |
/* Reverse changes made by migrate_page_copy() */ if (TestClearPageActive(new_page)) SetPageActive(page); if (TestClearPageUnevictable(new_page)) SetPageUnevictable(page); |
b32967ff1 mm: numa: Add THP... |
1969 1970 1971 |
unlock_page(new_page); put_page(new_page); /* Free it */ |
a54a407fb mm: Close races b... |
1972 1973 |
/* Retake the callers reference and putback on LRU */ get_page(page); |
b32967ff1 mm: numa: Add THP... |
1974 |
putback_lru_page(page); |
599d0c954 mm, vmscan: move ... |
1975 |
mod_node_page_state(page_pgdat(page), |
a54a407fb mm: Close races b... |
1976 |
NR_ISOLATED_ANON + page_lru, -HPAGE_PMD_NR); |
eb4489f69 mm: numa: avoid u... |
1977 1978 |
goto out_unlock; |
b32967ff1 mm: numa: Add THP... |
1979 |
} |
101024596 mm: introduce do_... |
1980 |
entry = mk_huge_pmd(new_page, vma->vm_page_prot); |
f55e1014f Revert "mm, thp: ... |
1981 |
entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); |
b32967ff1 mm: numa: Add THP... |
1982 |
|
2b4847e73 mm: numa: seriali... |
1983 |
/* |
d7c339341 mm: thp: fix MADV... |
1984 1985 1986 1987 1988 1989 |
* Overwrite the old entry under pagetable lock and establish * the new PTE. Any parallel GUP will either observe the old * page blocking on the page lock, block on the page table * lock or observe the new page. The SetPageUptodate on the * new page and page_add_new_anon_rmap guarantee the copy is * visible before the pagetable update. |
2b4847e73 mm: numa: seriali... |
1990 |
*/ |
7066f0f93 mm: thp: fix mmu_... |
1991 |
page_add_anon_rmap(new_page, vma, start, true); |
d7c339341 mm: thp: fix MADV... |
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 |
/* * At this point the pmd is numa/protnone (i.e. non present) and the TLB * has already been flushed globally. So no TLB can be currently * caching this non present pmd mapping. There's no need to clear the * pmd before doing set_pmd_at(), nor to flush the TLB after * set_pmd_at(). Clearing the pmd here would introduce a race * condition against MADV_DONTNEED, because MADV_DONTNEED only holds the * mmap_sem for reading. If the pmd is set to NULL at any given time, * MADV_DONTNEED won't wait on the pmd lock and it'll skip clearing this * pmd. */ |
7066f0f93 mm: thp: fix mmu_... |
2003 |
set_pmd_at(mm, start, pmd, entry); |
ce4a9cc57 mm,numa: fix upda... |
2004 |
update_mmu_cache_pmd(vma, address, &entry); |
2b4847e73 mm: numa: seriali... |
2005 |
|
f4e177d12 mm/migrate.c: sta... |
2006 |
page_ref_unfreeze(page, 2); |
51afb12ba mm: page migratio... |
2007 |
mlock_migrate_page(new_page, page); |
d281ee614 rmap: add argumen... |
2008 |
page_remove_rmap(page, true); |
7cd12b4ab mm, page_owner: t... |
2009 |
set_page_owner_migrate_reason(new_page, MR_NUMA_MISPLACED); |
2b4847e73 mm: numa: seriali... |
2010 |
|
c4088ebdc mm: convert the r... |
2011 |
spin_unlock(ptl); |
b32967ff1 mm: numa: Add THP... |
2012 |
|
11de9927f mm: numa: add mig... |
2013 2014 2015 |
/* Take an "isolate" reference and put new page on the LRU. */ get_page(new_page); putback_lru_page(new_page); |
b32967ff1 mm: numa: Add THP... |
2016 2017 2018 2019 2020 2021 2022 |
unlock_page(new_page); unlock_page(page); put_page(page); /* Drop the rmap reference */ put_page(page); /* Drop the LRU isolation reference */ count_vm_events(PGMIGRATE_SUCCESS, HPAGE_PMD_NR); count_vm_numa_events(NUMA_PAGE_MIGRATE, HPAGE_PMD_NR); |
599d0c954 mm, vmscan: move ... |
2023 |
mod_node_page_state(page_pgdat(page), |
b32967ff1 mm: numa: Add THP... |
2024 2025 2026 |
NR_ISOLATED_ANON + page_lru, -HPAGE_PMD_NR); return isolated; |
340ef3902 mm: numa: cleanup... |
2027 2028 |
out_fail: count_vm_events(PGMIGRATE_FAIL, HPAGE_PMD_NR); |
2b4847e73 mm: numa: seriali... |
2029 2030 |
ptl = pmd_lock(mm, pmd); if (pmd_same(*pmd, entry)) { |
4d9424669 mm: convert p[te|... |
2031 |
entry = pmd_modify(entry, vma->vm_page_prot); |
7066f0f93 mm: thp: fix mmu_... |
2032 |
set_pmd_at(mm, start, pmd, entry); |
2b4847e73 mm: numa: seriali... |
2033 2034 2035 |
update_mmu_cache_pmd(vma, address, &entry); } spin_unlock(ptl); |
a54a407fb mm: Close races b... |
2036 |
|
eb4489f69 mm: numa: avoid u... |
2037 |
out_unlock: |
340ef3902 mm: numa: cleanup... |
2038 |
unlock_page(page); |
b32967ff1 mm: numa: Add THP... |
2039 |
put_page(page); |
b32967ff1 mm: numa: Add THP... |
2040 2041 |
return 0; } |
7039e1dbe mm: migrate: Intr... |
2042 2043 2044 |
#endif /* CONFIG_NUMA_BALANCING */ #endif /* CONFIG_NUMA */ |
8763cb45a mm/migrate: new m... |
2045 |
|
6b368cd4a mm/hmm: avoid blo... |
2046 |
#if defined(CONFIG_MIGRATE_VMA_HELPER) |
8763cb45a mm/migrate: new m... |
2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 |
struct migrate_vma { struct vm_area_struct *vma; unsigned long *dst; unsigned long *src; unsigned long cpages; unsigned long npages; unsigned long start; unsigned long end; }; static int migrate_vma_collect_hole(unsigned long start, unsigned long end, struct mm_walk *walk) { struct migrate_vma *migrate = walk->private; unsigned long addr; for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) { |
e20d103b6 mm/migrate: fix i... |
2065 |
migrate->src[migrate->npages] = MIGRATE_PFN_MIGRATE; |
8315ada7f mm/migrate: allow... |
2066 |
migrate->dst[migrate->npages] = 0; |
e20d103b6 mm/migrate: fix i... |
2067 |
migrate->npages++; |
8315ada7f mm/migrate: allow... |
2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 |
migrate->cpages++; } return 0; } static int migrate_vma_collect_skip(unsigned long start, unsigned long end, struct mm_walk *walk) { struct migrate_vma *migrate = walk->private; unsigned long addr; for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) { |
8763cb45a mm/migrate: new m... |
2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 |
migrate->dst[migrate->npages] = 0; migrate->src[migrate->npages++] = 0; } return 0; } static int migrate_vma_collect_pmd(pmd_t *pmdp, unsigned long start, unsigned long end, struct mm_walk *walk) { struct migrate_vma *migrate = walk->private; struct vm_area_struct *vma = walk->vma; struct mm_struct *mm = vma->vm_mm; |
8c3328f1f mm/migrate: migra... |
2097 |
unsigned long addr = start, unmapped = 0; |
8763cb45a mm/migrate: new m... |
2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 |
spinlock_t *ptl; pte_t *ptep; again: if (pmd_none(*pmdp)) return migrate_vma_collect_hole(start, end, walk); if (pmd_trans_huge(*pmdp)) { struct page *page; ptl = pmd_lock(mm, pmdp); if (unlikely(!pmd_trans_huge(*pmdp))) { spin_unlock(ptl); goto again; } page = pmd_page(*pmdp); if (is_huge_zero_page(page)) { spin_unlock(ptl); split_huge_pmd(vma, pmdp, addr); if (pmd_trans_unstable(pmdp)) |
8315ada7f mm/migrate: allow... |
2119 |
return migrate_vma_collect_skip(start, end, |
8763cb45a mm/migrate: new m... |
2120 2121 2122 2123 2124 2125 2126 |
walk); } else { int ret; get_page(page); spin_unlock(ptl); if (unlikely(!trylock_page(page))) |
8315ada7f mm/migrate: allow... |
2127 |
return migrate_vma_collect_skip(start, end, |
8763cb45a mm/migrate: new m... |
2128 2129 2130 2131 |
walk); ret = split_huge_page(page); unlock_page(page); put_page(page); |
8315ada7f mm/migrate: allow... |
2132 2133 2134 2135 |
if (ret) return migrate_vma_collect_skip(start, end, walk); if (pmd_none(*pmdp)) |
8763cb45a mm/migrate: new m... |
2136 2137 2138 2139 2140 2141 |
return migrate_vma_collect_hole(start, end, walk); } } if (unlikely(pmd_bad(*pmdp))) |
8315ada7f mm/migrate: allow... |
2142 |
return migrate_vma_collect_skip(start, end, walk); |
8763cb45a mm/migrate: new m... |
2143 2144 |
ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); |
8c3328f1f mm/migrate: migra... |
2145 |
arch_enter_lazy_mmu_mode(); |
8763cb45a mm/migrate: new m... |
2146 2147 2148 |
for (; addr < end; addr += PAGE_SIZE, ptep++) { unsigned long mpfn, pfn; struct page *page; |
8c3328f1f mm/migrate: migra... |
2149 |
swp_entry_t entry; |
8763cb45a mm/migrate: new m... |
2150 2151 2152 2153 |
pte_t pte; pte = *ptep; pfn = pte_pfn(pte); |
a5430dda8 mm/migrate: suppo... |
2154 |
if (pte_none(pte)) { |
8315ada7f mm/migrate: allow... |
2155 2156 2157 |
mpfn = MIGRATE_PFN_MIGRATE; migrate->cpages++; pfn = 0; |
8763cb45a mm/migrate: new m... |
2158 2159 |
goto next; } |
a5430dda8 mm/migrate: suppo... |
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 |
if (!pte_present(pte)) { mpfn = pfn = 0; /* * Only care about unaddressable device page special * page table entry. Other special swap entries are not * migratable, and we ignore regular swapped page. */ entry = pte_to_swp_entry(pte); if (!is_device_private_entry(entry)) goto next; page = device_private_entry_to_page(entry); mpfn = migrate_pfn(page_to_pfn(page))| MIGRATE_PFN_DEVICE | MIGRATE_PFN_MIGRATE; if (is_write_device_private_entry(entry)) mpfn |= MIGRATE_PFN_WRITE; } else { |
8315ada7f mm/migrate: allow... |
2178 2179 2180 2181 2182 2183 |
if (is_zero_pfn(pfn)) { mpfn = MIGRATE_PFN_MIGRATE; migrate->cpages++; pfn = 0; goto next; } |
df6ad6983 mm/device-public-... |
2184 |
page = _vm_normal_page(migrate->vma, addr, pte, true); |
a5430dda8 mm/migrate: suppo... |
2185 2186 2187 |
mpfn = migrate_pfn(pfn) | MIGRATE_PFN_MIGRATE; mpfn |= pte_write(pte) ? MIGRATE_PFN_WRITE : 0; } |
8763cb45a mm/migrate: new m... |
2188 |
/* FIXME support THP */ |
8763cb45a mm/migrate: new m... |
2189 2190 2191 2192 |
if (!page || !page->mapping || PageTransCompound(page)) { mpfn = pfn = 0; goto next; } |
a5430dda8 mm/migrate: suppo... |
2193 |
pfn = page_to_pfn(page); |
8763cb45a mm/migrate: new m... |
2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 |
/* * By getting a reference on the page we pin it and that blocks * any kind of migration. Side effect is that it "freezes" the * pte. * * We drop this reference after isolating the page from the lru * for non device page (device page are not on the lru and thus * can't be dropped from it). */ get_page(page); migrate->cpages++; |
8763cb45a mm/migrate: new m... |
2206 |
|
8c3328f1f mm/migrate: migra... |
2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 |
/* * Optimize for the common case where page is only mapped once * in one process. If we can lock the page, then we can safely * set up a special migration page table entry now. */ if (trylock_page(page)) { pte_t swp_pte; mpfn |= MIGRATE_PFN_LOCKED; ptep_get_and_clear(mm, addr, ptep); /* Setup special migration page table entry */ |
07707125a mm/migrate: prope... |
2219 2220 |
entry = make_migration_entry(page, mpfn & MIGRATE_PFN_WRITE); |
8c3328f1f mm/migrate: migra... |
2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 |
swp_pte = swp_entry_to_pte(entry); if (pte_soft_dirty(pte)) swp_pte = pte_swp_mksoft_dirty(swp_pte); set_pte_at(mm, addr, ptep, swp_pte); /* * This is like regular unmap: we remove the rmap and * drop page refcount. Page won't be freed, as we took * a reference just above. */ page_remove_rmap(page, false); put_page(page); |
a5430dda8 mm/migrate: suppo... |
2233 2234 2235 |
if (pte_present(pte)) unmapped++; |
8c3328f1f mm/migrate: migra... |
2236 |
} |
8763cb45a mm/migrate: new m... |
2237 |
next: |
a5430dda8 mm/migrate: suppo... |
2238 |
migrate->dst[migrate->npages] = 0; |
8763cb45a mm/migrate: new m... |
2239 2240 |
migrate->src[migrate->npages++] = mpfn; } |
8c3328f1f mm/migrate: migra... |
2241 |
arch_leave_lazy_mmu_mode(); |
8763cb45a mm/migrate: new m... |
2242 |
pte_unmap_unlock(ptep - 1, ptl); |
8c3328f1f mm/migrate: migra... |
2243 2244 2245 |
/* Only flush the TLB if we actually modified any entries */ if (unmapped) flush_tlb_range(walk->vma, start, end); |
8763cb45a mm/migrate: new m... |
2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 |
return 0; } /* * migrate_vma_collect() - collect pages over a range of virtual addresses * @migrate: migrate struct containing all migration information * * This will walk the CPU page table. For each virtual address backed by a * valid page, it updates the src array and takes a reference on the page, in * order to pin the page until we lock it and unmap it. */ static void migrate_vma_collect(struct migrate_vma *migrate) { |
ac46d4f3c mm/mmu_notifier: ... |
2259 |
struct mmu_notifier_range range; |
8763cb45a mm/migrate: new m... |
2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 |
struct mm_walk mm_walk; mm_walk.pmd_entry = migrate_vma_collect_pmd; mm_walk.pte_entry = NULL; mm_walk.pte_hole = migrate_vma_collect_hole; mm_walk.hugetlb_entry = NULL; mm_walk.test_walk = NULL; mm_walk.vma = migrate->vma; mm_walk.mm = migrate->vma->vm_mm; mm_walk.private = migrate; |
7269f9999 mm/mmu_notifier: ... |
2270 |
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, NULL, mm_walk.mm, |
6f4f13e8d mm/mmu_notifier: ... |
2271 |
migrate->start, |
ac46d4f3c mm/mmu_notifier: ... |
2272 2273 |
migrate->end); mmu_notifier_invalidate_range_start(&range); |
8763cb45a mm/migrate: new m... |
2274 |
walk_page_range(migrate->start, migrate->end, &mm_walk); |
ac46d4f3c mm/mmu_notifier: ... |
2275 |
mmu_notifier_invalidate_range_end(&range); |
8763cb45a mm/migrate: new m... |
2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 |
migrate->end = migrate->start + (migrate->npages << PAGE_SHIFT); } /* * migrate_vma_check_page() - check if page is pinned or not * @page: struct page to check * * Pinned pages cannot be migrated. This is the same test as in * migrate_page_move_mapping(), except that here we allow migration of a * ZONE_DEVICE page. */ static bool migrate_vma_check_page(struct page *page) { /* * One extra ref because caller holds an extra reference, either from * isolate_lru_page() for a regular page, or migrate_vma_collect() for * a device page. */ int extra = 1; /* * FIXME support THP (transparent huge page), it is bit more complex to * check them than regular pages, because they can be mapped with a pmd * or with a pte (split pte mapping). */ if (PageCompound(page)) return false; |
a5430dda8 mm/migrate: suppo... |
2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 |
/* Page from ZONE_DEVICE have one extra reference */ if (is_zone_device_page(page)) { /* * Private page can never be pin as they have no valid pte and * GUP will fail for those. Yet if there is a pending migration * a thread might try to wait on the pte migration entry and * will bump the page reference count. Sadly there is no way to * differentiate a regular pin from migration wait. Hence to * avoid 2 racing thread trying to migrate back to CPU to enter * infinite loop (one stoping migration because the other is * waiting on pte migration entry). We always return true here. * * FIXME proper solution is to rework migration_entry_wait() so * it does not need to take a reference on page. */ if (is_device_private_page(page)) return true; |
df6ad6983 mm/device-public-... |
2321 2322 2323 2324 2325 2326 2327 |
/* * Only allow device public page to be migrated and account for * the extra reference count imply by ZONE_DEVICE pages. */ if (!is_device_public_page(page)) return false; extra++; |
a5430dda8 mm/migrate: suppo... |
2328 |
} |
df6ad6983 mm/device-public-... |
2329 2330 2331 |
/* For file back page */ if (page_mapping(page)) extra += 1 + page_has_private(page); |
8763cb45a mm/migrate: new m... |
2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 |
if ((page_count(page) - extra) > page_mapcount(page)) return false; return true; } /* * migrate_vma_prepare() - lock pages and isolate them from the lru * @migrate: migrate struct containing all migration information * * This locks pages that have been collected by migrate_vma_collect(). Once each * page is locked it is isolated from the lru (for non-device pages). Finally, * the ref taken by migrate_vma_collect() is dropped, as locked pages cannot be * migrated by concurrent kernel threads. */ static void migrate_vma_prepare(struct migrate_vma *migrate) { const unsigned long npages = migrate->npages; |
8c3328f1f mm/migrate: migra... |
2350 2351 |
const unsigned long start = migrate->start; unsigned long addr, i, restore = 0; |
8763cb45a mm/migrate: new m... |
2352 |
bool allow_drain = true; |
8763cb45a mm/migrate: new m... |
2353 2354 2355 2356 2357 |
lru_add_drain(); for (i = 0; (i < npages) && migrate->cpages; i++) { struct page *page = migrate_pfn_to_page(migrate->src[i]); |
8c3328f1f mm/migrate: migra... |
2358 |
bool remap = true; |
8763cb45a mm/migrate: new m... |
2359 2360 2361 |
if (!page) continue; |
8c3328f1f mm/migrate: migra... |
2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 |
if (!(migrate->src[i] & MIGRATE_PFN_LOCKED)) { /* * Because we are migrating several pages there can be * a deadlock between 2 concurrent migration where each * are waiting on each other page lock. * * Make migrate_vma() a best effort thing and backoff * for any page we can not lock right away. */ if (!trylock_page(page)) { migrate->src[i] = 0; migrate->cpages--; put_page(page); continue; } remap = false; migrate->src[i] |= MIGRATE_PFN_LOCKED; |
8763cb45a mm/migrate: new m... |
2379 |
} |
8763cb45a mm/migrate: new m... |
2380 |
|
a5430dda8 mm/migrate: suppo... |
2381 2382 2383 2384 2385 2386 2387 |
/* ZONE_DEVICE pages are not on LRU */ if (!is_zone_device_page(page)) { if (!PageLRU(page) && allow_drain) { /* Drain CPU's pagevec */ lru_add_drain_all(); allow_drain = false; } |
8763cb45a mm/migrate: new m... |
2388 |
|
a5430dda8 mm/migrate: suppo... |
2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 |
if (isolate_lru_page(page)) { if (remap) { migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; migrate->cpages--; restore++; } else { migrate->src[i] = 0; unlock_page(page); migrate->cpages--; put_page(page); } continue; |
8c3328f1f mm/migrate: migra... |
2401 |
} |
a5430dda8 mm/migrate: suppo... |
2402 2403 2404 |
/* Drop the reference we took in collect */ put_page(page); |
8763cb45a mm/migrate: new m... |
2405 2406 2407 |
} if (!migrate_vma_check_page(page)) { |
8c3328f1f mm/migrate: migra... |
2408 2409 2410 2411 |
if (remap) { migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; migrate->cpages--; restore++; |
8763cb45a mm/migrate: new m... |
2412 |
|
a5430dda8 mm/migrate: suppo... |
2413 2414 2415 2416 |
if (!is_zone_device_page(page)) { get_page(page); putback_lru_page(page); } |
8c3328f1f mm/migrate: migra... |
2417 2418 2419 2420 |
} else { migrate->src[i] = 0; unlock_page(page); migrate->cpages--; |
a5430dda8 mm/migrate: suppo... |
2421 2422 2423 2424 |
if (!is_zone_device_page(page)) putback_lru_page(page); else put_page(page); |
8c3328f1f mm/migrate: migra... |
2425 |
} |
8763cb45a mm/migrate: new m... |
2426 2427 |
} } |
8c3328f1f mm/migrate: migra... |
2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 |
for (i = 0, addr = start; i < npages && restore; i++, addr += PAGE_SIZE) { struct page *page = migrate_pfn_to_page(migrate->src[i]); if (!page || (migrate->src[i] & MIGRATE_PFN_MIGRATE)) continue; remove_migration_pte(page, migrate->vma, addr, page); migrate->src[i] = 0; unlock_page(page); put_page(page); restore--; } |
8763cb45a mm/migrate: new m... |
2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 |
} /* * migrate_vma_unmap() - replace page mapping with special migration pte entry * @migrate: migrate struct containing all migration information * * Replace page mapping (CPU page table pte) with a special migration pte entry * and check again if it has been pinned. Pinned pages are restored because we * cannot migrate them. * * This is the last step before we call the device driver callback to allocate * destination memory and copy contents of original page over to new page. */ static void migrate_vma_unmap(struct migrate_vma *migrate) { int flags = TTU_MIGRATION | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; const unsigned long npages = migrate->npages; const unsigned long start = migrate->start; unsigned long addr, i, restore = 0; for (i = 0; i < npages; i++) { struct page *page = migrate_pfn_to_page(migrate->src[i]); if (!page || !(migrate->src[i] & MIGRATE_PFN_MIGRATE)) continue; |
8c3328f1f mm/migrate: migra... |
2467 2468 2469 2470 |
if (page_mapped(page)) { try_to_unmap(page, flags); if (page_mapped(page)) goto restore; |
8763cb45a mm/migrate: new m... |
2471 |
} |
8c3328f1f mm/migrate: migra... |
2472 2473 2474 2475 2476 2477 2478 2479 |
if (migrate_vma_check_page(page)) continue; restore: migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; migrate->cpages--; restore++; |
8763cb45a mm/migrate: new m... |
2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 |
} for (addr = start, i = 0; i < npages && restore; addr += PAGE_SIZE, i++) { struct page *page = migrate_pfn_to_page(migrate->src[i]); if (!page || (migrate->src[i] & MIGRATE_PFN_MIGRATE)) continue; remove_migration_ptes(page, page, false); migrate->src[i] = 0; unlock_page(page); restore--; |
a5430dda8 mm/migrate: suppo... |
2493 2494 2495 2496 |
if (is_zone_device_page(page)) put_page(page); else putback_lru_page(page); |
8763cb45a mm/migrate: new m... |
2497 2498 |
} } |
8315ada7f mm/migrate: allow... |
2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 |
static void migrate_vma_insert_page(struct migrate_vma *migrate, unsigned long addr, struct page *page, unsigned long *src, unsigned long *dst) { struct vm_area_struct *vma = migrate->vma; struct mm_struct *mm = vma->vm_mm; struct mem_cgroup *memcg; bool flush = false; spinlock_t *ptl; pte_t entry; pgd_t *pgdp; p4d_t *p4dp; pud_t *pudp; pmd_t *pmdp; pte_t *ptep; /* Only allow populating anonymous memory */ if (!vma_is_anonymous(vma)) goto abort; pgdp = pgd_offset(mm, addr); p4dp = p4d_alloc(mm, pgdp, addr); if (!p4dp) goto abort; pudp = pud_alloc(mm, p4dp, addr); if (!pudp) goto abort; pmdp = pmd_alloc(mm, pudp, addr); if (!pmdp) goto abort; if (pmd_trans_huge(*pmdp) || pmd_devmap(*pmdp)) goto abort; /* * Use pte_alloc() instead of pte_alloc_map(). We can't run * pte_offset_map() on pmds where a huge pmd might be created * from a different thread. * * pte_alloc_map() is safe to use under down_write(mmap_sem) or when * parallel threads are excluded by other means. * * Here we only have down_read(mmap_sem). */ |
4cf589249 mm: treewide: rem... |
2545 |
if (pte_alloc(mm, pmdp)) |
8315ada7f mm/migrate: allow... |
2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 |
goto abort; /* See the comment in pte_alloc_one_map() */ if (unlikely(pmd_trans_unstable(pmdp))) goto abort; if (unlikely(anon_vma_prepare(vma))) goto abort; if (mem_cgroup_try_charge(page, vma->vm_mm, GFP_KERNEL, &memcg, false)) goto abort; /* * The memory barrier inside __SetPageUptodate makes sure that * preceding stores to the page contents become visible before * the set_pte_at() write. */ __SetPageUptodate(page); |
df6ad6983 mm/device-public-... |
2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 |
if (is_zone_device_page(page)) { if (is_device_private_page(page)) { swp_entry_t swp_entry; swp_entry = make_device_private_entry(page, vma->vm_flags & VM_WRITE); entry = swp_entry_to_pte(swp_entry); } else if (is_device_public_page(page)) { entry = pte_mkold(mk_pte(page, READ_ONCE(vma->vm_page_prot))); if (vma->vm_flags & VM_WRITE) entry = pte_mkwrite(pte_mkdirty(entry)); entry = pte_mkdevmap(entry); } |
8315ada7f mm/migrate: allow... |
2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 |
} else { entry = mk_pte(page, vma->vm_page_prot); if (vma->vm_flags & VM_WRITE) entry = pte_mkwrite(pte_mkdirty(entry)); } ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); if (pte_present(*ptep)) { unsigned long pfn = pte_pfn(*ptep); if (!is_zero_pfn(pfn)) { pte_unmap_unlock(ptep, ptl); mem_cgroup_cancel_charge(page, memcg, false); goto abort; } flush = true; } else if (!pte_none(*ptep)) { pte_unmap_unlock(ptep, ptl); mem_cgroup_cancel_charge(page, memcg, false); goto abort; } /* * Check for usefaultfd but do not deliver the fault. Instead, * just back off. */ if (userfaultfd_missing(vma)) { pte_unmap_unlock(ptep, ptl); mem_cgroup_cancel_charge(page, memcg, false); goto abort; } inc_mm_counter(mm, MM_ANONPAGES); page_add_new_anon_rmap(page, vma, addr, false); mem_cgroup_commit_charge(page, memcg, false, false); if (!is_zone_device_page(page)) lru_cache_add_active_or_unevictable(page, vma); get_page(page); if (flush) { flush_cache_page(vma, addr, pte_pfn(*ptep)); ptep_clear_flush_notify(vma, addr, ptep); set_pte_at_notify(mm, addr, ptep, entry); update_mmu_cache(vma, addr, ptep); } else { /* No need to invalidate - it was non-present before */ set_pte_at(mm, addr, ptep, entry); update_mmu_cache(vma, addr, ptep); } pte_unmap_unlock(ptep, ptl); *src = MIGRATE_PFN_MIGRATE; return; abort: *src &= ~MIGRATE_PFN_MIGRATE; } |
8763cb45a mm/migrate: new m... |
2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 |
/* * migrate_vma_pages() - migrate meta-data from src page to dst page * @migrate: migrate struct containing all migration information * * This migrates struct page meta-data from source struct page to destination * struct page. This effectively finishes the migration from source page to the * destination page. */ static void migrate_vma_pages(struct migrate_vma *migrate) { const unsigned long npages = migrate->npages; const unsigned long start = migrate->start; |
ac46d4f3c mm/mmu_notifier: ... |
2645 2646 |
struct mmu_notifier_range range; unsigned long addr, i; |
8315ada7f mm/migrate: allow... |
2647 |
bool notified = false; |
8763cb45a mm/migrate: new m... |
2648 2649 2650 2651 2652 2653 |
for (i = 0, addr = start; i < npages; addr += PAGE_SIZE, i++) { struct page *newpage = migrate_pfn_to_page(migrate->dst[i]); struct page *page = migrate_pfn_to_page(migrate->src[i]); struct address_space *mapping; int r; |
8315ada7f mm/migrate: allow... |
2654 2655 |
if (!newpage) { migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; |
8763cb45a mm/migrate: new m... |
2656 |
continue; |
8315ada7f mm/migrate: allow... |
2657 2658 2659 2660 2661 2662 2663 |
} if (!page) { if (!(migrate->src[i] & MIGRATE_PFN_MIGRATE)) { continue; } if (!notified) { |
8315ada7f mm/migrate: allow... |
2664 |
notified = true; |
ac46d4f3c mm/mmu_notifier: ... |
2665 2666 |
mmu_notifier_range_init(&range, |
7269f9999 mm/mmu_notifier: ... |
2667 |
MMU_NOTIFY_CLEAR, 0, |
6f4f13e8d mm/mmu_notifier: ... |
2668 |
NULL, |
ac46d4f3c mm/mmu_notifier: ... |
2669 2670 2671 |
migrate->vma->vm_mm, addr, migrate->end); mmu_notifier_invalidate_range_start(&range); |
8315ada7f mm/migrate: allow... |
2672 2673 2674 2675 |
} migrate_vma_insert_page(migrate, addr, newpage, &migrate->src[i], &migrate->dst[i]); |
8763cb45a mm/migrate: new m... |
2676 |
continue; |
8315ada7f mm/migrate: allow... |
2677 |
} |
8763cb45a mm/migrate: new m... |
2678 2679 |
mapping = page_mapping(page); |
a5430dda8 mm/migrate: suppo... |
2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 |
if (is_zone_device_page(newpage)) { if (is_device_private_page(newpage)) { /* * For now only support private anonymous when * migrating to un-addressable device memory. */ if (mapping) { migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; continue; } |
df6ad6983 mm/device-public-... |
2690 |
} else if (!is_device_public_page(newpage)) { |
a5430dda8 mm/migrate: suppo... |
2691 2692 2693 2694 2695 2696 2697 2698 |
/* * Other types of ZONE_DEVICE page are not * supported. */ migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; continue; } } |
8763cb45a mm/migrate: new m... |
2699 2700 2701 2702 |
r = migrate_page(mapping, newpage, page, MIGRATE_SYNC_NO_COPY); if (r != MIGRATEPAGE_SUCCESS) migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; } |
8315ada7f mm/migrate: allow... |
2703 |
|
4645b9fe8 mm/mmu_notifier: ... |
2704 2705 2706 2707 2708 |
/* * No need to double call mmu_notifier->invalidate_range() callback as * the above ptep_clear_flush_notify() inside migrate_vma_insert_page() * did already call it. */ |
8315ada7f mm/migrate: allow... |
2709 |
if (notified) |
ac46d4f3c mm/mmu_notifier: ... |
2710 |
mmu_notifier_invalidate_range_only_end(&range); |
8763cb45a mm/migrate: new m... |
2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 |
} /* * migrate_vma_finalize() - restore CPU page table entry * @migrate: migrate struct containing all migration information * * This replaces the special migration pte entry with either a mapping to the * new page if migration was successful for that page, or to the original page * otherwise. * * This also unlocks the pages and puts them back on the lru, or drops the extra * refcount, for device pages. */ static void migrate_vma_finalize(struct migrate_vma *migrate) { const unsigned long npages = migrate->npages; unsigned long i; for (i = 0; i < npages; i++) { struct page *newpage = migrate_pfn_to_page(migrate->dst[i]); struct page *page = migrate_pfn_to_page(migrate->src[i]); |
8315ada7f mm/migrate: allow... |
2732 2733 2734 2735 2736 |
if (!page) { if (newpage) { unlock_page(newpage); put_page(newpage); } |
8763cb45a mm/migrate: new m... |
2737 |
continue; |
8315ada7f mm/migrate: allow... |
2738 |
} |
8763cb45a mm/migrate: new m... |
2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 |
if (!(migrate->src[i] & MIGRATE_PFN_MIGRATE) || !newpage) { if (newpage) { unlock_page(newpage); put_page(newpage); } newpage = page; } remove_migration_ptes(page, newpage, false); unlock_page(page); migrate->cpages--; |
a5430dda8 mm/migrate: suppo... |
2750 2751 2752 2753 |
if (is_zone_device_page(page)) put_page(page); else putback_lru_page(page); |
8763cb45a mm/migrate: new m... |
2754 2755 2756 |
if (newpage != page) { unlock_page(newpage); |
a5430dda8 mm/migrate: suppo... |
2757 2758 2759 2760 |
if (is_zone_device_page(newpage)) put_page(newpage); else putback_lru_page(newpage); |
8763cb45a mm/migrate: new m... |
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} } } /* * migrate_vma() - migrate a range of memory inside vma * * @ops: migration callback for allocating destination memory and copying * @vma: virtual memory area containing the range to be migrated * @start: start address of the range to migrate (inclusive) * @end: end address of the range to migrate (exclusive) * @src: array of hmm_pfn_t containing source pfns * @dst: array of hmm_pfn_t containing destination pfns * @private: pointer passed back to each of the callback * Returns: 0 on success, error code otherwise * * This function tries to migrate a range of memory virtual address range, using * callbacks to allocate and copy memory from source to destination. First it * collects all the pages backing each virtual address in the range, saving this * inside the src array. Then it locks those pages and unmaps them. Once the pages * are locked and unmapped, it checks whether each page is pinned or not. Pages * that aren't pinned have the MIGRATE_PFN_MIGRATE flag set (by this function) * in the corresponding src array entry. It then restores any pages that are * pinned, by remapping and unlocking those pages. * * At this point it calls the alloc_and_copy() callback. For documentation on * what is expected from that callback, see struct migrate_vma_ops comments in * include/linux/migrate.h * * After the alloc_and_copy() callback, this function goes over each entry in * the src array that has the MIGRATE_PFN_VALID and MIGRATE_PFN_MIGRATE flag * set. If the corresponding entry in dst array has MIGRATE_PFN_VALID flag set, * then the function tries to migrate struct page information from the source * struct page to the destination struct page. If it fails to migrate the struct * page information, then it clears the MIGRATE_PFN_MIGRATE flag in the src * array. * * At this point all successfully migrated pages have an entry in the src * array with MIGRATE_PFN_VALID and MIGRATE_PFN_MIGRATE flag set and the dst * array entry with MIGRATE_PFN_VALID flag set. * * It then calls the finalize_and_map() callback. See comments for "struct * migrate_vma_ops", in include/linux/migrate.h for details about * finalize_and_map() behavior. * * After the finalize_and_map() callback, for successfully migrated pages, this * function updates the CPU page table to point to new pages, otherwise it * restores the CPU page table to point to the original source pages. * * Function returns 0 after the above steps, even if no pages were migrated * (The function only returns an error if any of the arguments are invalid.) * * Both src and dst array must be big enough for (end - start) >> PAGE_SHIFT * unsigned long entries. */ int migrate_vma(const struct migrate_vma_ops *ops, struct vm_area_struct *vma, unsigned long start, unsigned long end, unsigned long *src, unsigned long *dst, void *private) { struct migrate_vma migrate; /* Sanity check the arguments */ start &= PAGE_MASK; end &= PAGE_MASK; |
e1fb4a086 dax: remove VM_MI... |
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if (!vma || is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_SPECIAL) || vma_is_dax(vma)) |
8763cb45a mm/migrate: new m... |
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return -EINVAL; if (start < vma->vm_start || start >= vma->vm_end) return -EINVAL; if (end <= vma->vm_start || end > vma->vm_end) return -EINVAL; if (!ops || !src || !dst || start >= end) return -EINVAL; memset(src, 0, sizeof(*src) * ((end - start) >> PAGE_SHIFT)); migrate.src = src; migrate.dst = dst; migrate.start = start; migrate.npages = 0; migrate.cpages = 0; migrate.end = end; migrate.vma = vma; /* Collect, and try to unmap source pages */ migrate_vma_collect(&migrate); if (!migrate.cpages) return 0; /* Lock and isolate page */ migrate_vma_prepare(&migrate); if (!migrate.cpages) return 0; /* Unmap pages */ migrate_vma_unmap(&migrate); if (!migrate.cpages) return 0; /* * At this point pages are locked and unmapped, and thus they have * stable content and can safely be copied to destination memory that * is allocated by the callback. * * Note that migration can fail in migrate_vma_struct_page() for each * individual page. */ ops->alloc_and_copy(vma, src, dst, start, end, private); /* This does the real migration of struct page */ migrate_vma_pages(&migrate); ops->finalize_and_map(vma, src, dst, start, end, private); /* Unlock and remap pages */ migrate_vma_finalize(&migrate); return 0; } EXPORT_SYMBOL(migrate_vma); |
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#endif /* defined(MIGRATE_VMA_HELPER) */ |