}
/*
- * Add isolated pages on the list back to the LRU under page lock
- * to avoid leaking evictable pages back onto unevictable list.
- */
-void putback_lru_pages(struct list_head *l)
-{
- struct page *page;
- struct page *page2;
-
- list_for_each_entry_safe(page, page2, l, lru) {
- list_del(&page->lru);
- dec_zone_page_state(page, NR_ISOLATED_ANON +
- page_is_file_cache(page));
- putback_lru_page(page);
- }
-}
-
-/*
* Put previously isolated pages back onto the appropriate lists
* from where they were once taken off for compaction/migration.
*
- * This function shall be used instead of putback_lru_pages(),
- * whenever the isolated pageset has been built by isolate_migratepages_range()
+ * 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().
*/
void putback_movable_pages(struct list_head *l)
{
pte = pte_mkold(mk_pte(new, vma->vm_page_prot));
if (pte_swp_soft_dirty(*ptep))
pte = pte_mksoft_dirty(pte);
+
+ /* Recheck VMA as permissions can change since migration started */
if (is_write_migration_entry(entry))
- pte = pte_mkwrite(pte);
+ pte = maybe_mkwrite(pte, vma);
+
#ifdef CONFIG_HUGETLB_PAGE
if (PageHuge(new)) {
pte = pte_mkhuge(pte);
}
/*
+ * Congratulations to trinity for discovering this bug.
+ * mm/fremap.c's remap_file_pages() accepts any range within a single vma to
+ * convert that vma to VM_NONLINEAR; and generic_file_remap_pages() will then
+ * replace the specified range by file ptes throughout (maybe populated after).
+ * If page migration finds a page within that range, while it's still located
+ * by vma_interval_tree rather than lost to i_mmap_nonlinear list, no problem:
+ * zap_pte() clears the temporary migration entry before mmap_sem is dropped.
+ * But if the migrating page is in a part of the vma outside the range to be
+ * remapped, then it will not be cleared, and remove_migration_ptes() needs to
+ * deal with it. Fortunately, this part of the vma is of course still linear,
+ * so we just need to use linear location on the nonlinear list.
+ */
+static int remove_linear_migration_ptes_from_nonlinear(struct page *page,
+ struct address_space *mapping, void *arg)
+{
+ struct vm_area_struct *vma;
+ /* hugetlbfs does not support remap_pages, so no huge pgoff worries */
+ pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+ unsigned long addr;
+
+ list_for_each_entry(vma,
+ &mapping->i_mmap_nonlinear, shared.nonlinear) {
+
+ addr = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
+ if (addr >= vma->vm_start && addr < vma->vm_end)
+ remove_migration_pte(page, vma, addr, arg);
+ }
+ return SWAP_AGAIN;
+}
+
+/*
* Get rid of all migration entries and replace them by
* references to the indicated page.
*/
static void remove_migration_ptes(struct page *old, struct page *new)
{
- rmap_walk(new, remove_migration_pte, old);
+ struct rmap_walk_control rwc = {
+ .rmap_one = remove_migration_pte,
+ .arg = old,
+ .file_nonlinear = remove_linear_migration_ptes_from_nonlinear,
+ };
+
+ rmap_walk(new, &rwc);
}
/*
if (PageUptodate(page))
SetPageUptodate(newpage);
if (TestClearPageActive(page)) {
- VM_BUG_ON(PageUnevictable(page));
+ VM_BUG_ON_PAGE(PageUnevictable(page), page);
SetPageActive(newpage);
} else if (TestClearPageUnevictable(page))
SetPageUnevictable(newpage);
* Migration functions
***********************************************************/
-/* Always fail migration. Used for mappings that are not movable */
-int fail_migrate_page(struct address_space *mapping,
- struct page *newpage, struct page *page)
-{
- return -EIO;
-}
-EXPORT_SYMBOL(fail_migrate_page);
-
/*
* Common logic to directly migrate a single page suitable for
* pages that do not use PagePrivate/PagePrivate2.
* free the metadata, so the page can be freed.
*/
if (!page->mapping) {
- VM_BUG_ON(PageAnon(page));
+ VM_BUG_ON_PAGE(PageAnon(page), page);
if (page_has_private(page)) {
try_to_free_buffers(page);
goto uncharge;
* Obtain the lock on page, remove all ptes and migrate the page
* to the newly allocated page in newpage.
*/
-static int unmap_and_move(new_page_t get_new_page, unsigned long private,
- struct page *page, int force, enum migrate_mode mode)
+static int unmap_and_move(new_page_t get_new_page, free_page_t put_new_page,
+ unsigned long private, struct page *page, int force,
+ enum migrate_mode mode)
{
int rc = 0;
int *result = NULL;
page_is_file_cache(page));
putback_lru_page(page);
}
+
/*
- * Move the new page to the LRU. If migration was not successful
- * then this will free the page.
+ * If migration was not successful and there's a freeing callback, use
+ * it. Otherwise, putback_lru_page() will drop the reference grabbed
+ * during isolation.
*/
- putback_lru_page(newpage);
+ if (rc != MIGRATEPAGE_SUCCESS && put_new_page) {
+ ClearPageSwapBacked(newpage);
+ put_new_page(newpage, private);
+ } else
+ putback_lru_page(newpage);
+
if (result) {
if (rc)
*result = rc;
* will wait in the page fault for migration to complete.
*/
static int unmap_and_move_huge_page(new_page_t get_new_page,
- unsigned long private, struct page *hpage,
- int force, enum migrate_mode mode)
+ free_page_t put_new_page, unsigned long private,
+ struct page *hpage, int force,
+ enum migrate_mode mode)
{
int rc = 0;
int *result = NULL;
- struct page *new_hpage = get_new_page(hpage, private, &result);
+ struct page *new_hpage;
struct anon_vma *anon_vma = NULL;
/*
* tables or check whether the hugepage is pmd-based or not before
* kicking migration.
*/
- if (!hugepage_migration_support(page_hstate(hpage)))
+ if (!hugepage_migration_support(page_hstate(hpage))) {
+ putback_active_hugepage(hpage);
return -ENOSYS;
+ }
+ new_hpage = get_new_page(hpage, private, &result);
if (!new_hpage)
return -ENOMEM;
if (!page_mapped(hpage))
rc = move_to_new_page(new_hpage, hpage, 1, mode);
- if (rc)
+ if (rc != MIGRATEPAGE_SUCCESS)
remove_migration_ptes(hpage, hpage);
if (anon_vma)
put_anon_vma(anon_vma);
- if (!rc)
+ if (rc == MIGRATEPAGE_SUCCESS)
hugetlb_cgroup_migrate(hpage, new_hpage);
unlock_page(hpage);
out:
if (rc != -EAGAIN)
putback_active_hugepage(hpage);
- put_page(new_hpage);
+
+ /*
+ * If migration was not successful and there's a freeing callback, use
+ * it. Otherwise, put_page() will drop the reference grabbed during
+ * isolation.
+ */
+ if (rc != MIGRATEPAGE_SUCCESS && put_new_page)
+ put_new_page(new_hpage, private);
+ else
+ put_page(new_hpage);
+
if (result) {
if (rc)
*result = rc;
* @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.
+ * @put_new_page: The function used to free target pages if migration
+ * fails, or NULL if no special handling is necessary.
* @private: Private data to be passed on to get_new_page()
* @mode: The migration mode that specifies the constraints for
* page migration, if any.
* Returns the number of pages that were not migrated, or an error code.
*/
int migrate_pages(struct list_head *from, new_page_t get_new_page,
- unsigned long private, enum migrate_mode mode, int reason)
+ free_page_t put_new_page, unsigned long private,
+ enum migrate_mode mode, int reason)
{
int retry = 1;
int nr_failed = 0;
if (PageHuge(page))
rc = unmap_and_move_huge_page(get_new_page,
- private, page, pass > 2, mode);
+ put_new_page, private, page,
+ pass > 2, mode);
else
- rc = unmap_and_move(get_new_page, private,
- page, pass > 2, mode);
+ rc = unmap_and_move(get_new_page, put_new_page,
+ private, page, pass > 2, mode);
switch(rc) {
case -ENOMEM:
nr_succeeded++;
break;
default:
- /* Permanent failure */
+ /*
+ * 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.
+ */
nr_failed++;
break;
}
pm->node);
else
return alloc_pages_exact_node(pm->node,
- GFP_HIGHUSER_MOVABLE | GFP_THISNODE, 0);
+ GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, 0);
}
/*
err = 0;
if (!list_empty(&pagelist)) {
- err = migrate_pages(&pagelist, new_page_node,
+ err = migrate_pages(&pagelist, new_page_node, NULL,
(unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
if (err)
putback_movable_pages(&pagelist);
struct page *newpage;
newpage = alloc_pages_exact_node(nid,
- (GFP_HIGHUSER_MOVABLE | GFP_THISNODE |
- __GFP_NOMEMALLOC | __GFP_NORETRY |
- __GFP_NOWARN) &
+ (GFP_HIGHUSER_MOVABLE |
+ __GFP_THISNODE | __GFP_NOMEMALLOC |
+ __GFP_NORETRY | __GFP_NOWARN) &
~GFP_IOFS, 0);
- if (newpage)
- page_cpupid_xchg_last(newpage, page_cpupid_last(page));
return newpage;
}
}
/* Returns true if the node is migrate rate-limited after the update */
-bool numamigrate_update_ratelimit(pg_data_t *pgdat, unsigned long nr_pages)
+static bool numamigrate_update_ratelimit(pg_data_t *pgdat,
+ unsigned long nr_pages)
{
- bool rate_limited = false;
-
/*
* Rate-limit the amount of data that is being migrated to a node.
* Optimal placement is no good if the memory bus is saturated and
* all the time is being spent migrating!
*/
- spin_lock(&pgdat->numabalancing_migrate_lock);
if (time_after(jiffies, pgdat->numabalancing_migrate_next_window)) {
+ spin_lock(&pgdat->numabalancing_migrate_lock);
pgdat->numabalancing_migrate_nr_pages = 0;
pgdat->numabalancing_migrate_next_window = jiffies +
msecs_to_jiffies(migrate_interval_millisecs);
+ spin_unlock(&pgdat->numabalancing_migrate_lock);
}
- if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages)
- rate_limited = true;
- else
- pgdat->numabalancing_migrate_nr_pages += nr_pages;
- spin_unlock(&pgdat->numabalancing_migrate_lock);
-
- return rate_limited;
+ if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages) {
+ trace_mm_numa_migrate_ratelimit(current, pgdat->node_id,
+ nr_pages);
+ return true;
+ }
+
+ /*
+ * This is an unlocked non-atomic update so errors are possible.
+ * The consequences are failing to migrate when we potentiall should
+ * have which is not severe enough to warrant locking. If it is ever
+ * a problem, it can be converted to a per-cpu counter.
+ */
+ pgdat->numabalancing_migrate_nr_pages += nr_pages;
+ return false;
}
-int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
+static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
{
int page_lru;
- VM_BUG_ON(compound_order(page) && !PageTransHuge(page));
+ VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page);
/* Avoid migrating to a node that is nearly full */
if (!migrate_balanced_pgdat(pgdat, 1UL << compound_order(page)))
list_add(&page->lru, &migratepages);
nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
- node, MIGRATE_ASYNC, MR_NUMA_MISPLACED);
+ NULL, node, MIGRATE_ASYNC,
+ MR_NUMA_MISPLACED);
if (nr_remaining) {
- putback_lru_pages(&migratepages);
+ if (!list_empty(&migratepages)) {
+ list_del(&page->lru);
+ dec_zone_page_state(page, NR_ISOLATED_ANON +
+ page_is_file_cache(page));
+ putback_lru_page(page);
+ }
isolated = 0;
} else
count_vm_numa_event(NUMA_PAGE_MIGRATE);
goto out_dropref;
new_page = alloc_pages_node(node,
- (GFP_TRANSHUGE | GFP_THISNODE) & ~__GFP_WAIT, HPAGE_PMD_ORDER);
+ (GFP_TRANSHUGE | __GFP_THISNODE) & ~__GFP_WAIT,
+ HPAGE_PMD_ORDER);
if (!new_page)
goto out_fail;
- page_cpupid_xchg_last(new_page, page_cpupid_last(page));
-
isolated = numamigrate_isolate_page(pgdat, page);
if (!isolated) {
put_page(new_page);
projects / platform / adaptation / renesas_rcar / renesas_kernel.git / blobdiff