diff options
Diffstat (limited to 'mm/compaction.c')
-rw-r--r-- | mm/compaction.c | 182 |
1 files changed, 118 insertions, 64 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index 1427366ad673..64df5fe052db 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -15,11 +15,11 @@ #include <linux/backing-dev.h> #include <linux/sysctl.h> #include <linux/sysfs.h> -#include <linux/balloon_compaction.h> #include <linux/page-isolation.h> #include <linux/kasan.h> #include <linux/kthread.h> #include <linux/freezer.h> +#include <linux/page_owner.h> #include "internal.h" #ifdef CONFIG_COMPACTION @@ -65,13 +65,27 @@ static unsigned long release_freepages(struct list_head *freelist) static void map_pages(struct list_head *list) { - struct page *page; + unsigned int i, order, nr_pages; + struct page *page, *next; + LIST_HEAD(tmp_list); + + list_for_each_entry_safe(page, next, list, lru) { + list_del(&page->lru); + + order = page_private(page); + nr_pages = 1 << order; - list_for_each_entry(page, list, lru) { - arch_alloc_page(page, 0); - kernel_map_pages(page, 1, 1); - kasan_alloc_pages(page, 0); + post_alloc_hook(page, order, __GFP_MOVABLE); + if (order) + split_page(page, order); + + for (i = 0; i < nr_pages; i++) { + list_add(&page->lru, &tmp_list); + page++; + } } + + list_splice(&tmp_list, list); } static inline bool migrate_async_suitable(int migratetype) @@ -81,6 +95,44 @@ static inline bool migrate_async_suitable(int migratetype) #ifdef CONFIG_COMPACTION +int PageMovable(struct page *page) +{ + struct address_space *mapping; + + VM_BUG_ON_PAGE(!PageLocked(page), page); + if (!__PageMovable(page)) + return 0; + + mapping = page_mapping(page); + if (mapping && mapping->a_ops && mapping->a_ops->isolate_page) + return 1; + + return 0; +} +EXPORT_SYMBOL(PageMovable); + +void __SetPageMovable(struct page *page, struct address_space *mapping) +{ + VM_BUG_ON_PAGE(!PageLocked(page), page); + VM_BUG_ON_PAGE((unsigned long)mapping & PAGE_MAPPING_MOVABLE, page); + page->mapping = (void *)((unsigned long)mapping | PAGE_MAPPING_MOVABLE); +} +EXPORT_SYMBOL(__SetPageMovable); + +void __ClearPageMovable(struct page *page) +{ + VM_BUG_ON_PAGE(!PageLocked(page), page); + VM_BUG_ON_PAGE(!PageMovable(page), page); + /* + * Clear registered address_space val with keeping PAGE_MAPPING_MOVABLE + * flag so that VM can catch up released page by driver after isolation. + * With it, VM migration doesn't try to put it back. + */ + page->mapping = (void *)((unsigned long)page->mapping & + PAGE_MAPPING_MOVABLE); +} +EXPORT_SYMBOL(__ClearPageMovable); + /* Do not skip compaction more than 64 times */ #define COMPACT_MAX_DEFER_SHIFT 6 @@ -368,12 +420,13 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, unsigned long flags = 0; bool locked = false; unsigned long blockpfn = *start_pfn; + unsigned int order; cursor = pfn_to_page(blockpfn); /* Isolate free pages. */ for (; blockpfn < end_pfn; blockpfn++, cursor++) { - int isolated, i; + int isolated; struct page *page = cursor; /* @@ -439,27 +492,25 @@ static unsigned long isolate_freepages_block(struct compact_control *cc, goto isolate_fail; } - /* Found a free page, break it into order-0 pages */ - isolated = split_free_page(page); - total_isolated += isolated; - for (i = 0; i < isolated; i++) { - list_add(&page->lru, freelist); - page++; - } + /* Found a free page, will break it into order-0 pages */ + order = page_order(page); + isolated = __isolate_free_page(page, order); + if (!isolated) + break; + set_page_private(page, order); - /* If a page was split, advance to the end of it */ - if (isolated) { - cc->nr_freepages += isolated; - if (!strict && - cc->nr_migratepages <= cc->nr_freepages) { - blockpfn += isolated; - break; - } + total_isolated += isolated; + cc->nr_freepages += isolated; + list_add_tail(&page->lru, freelist); - blockpfn += isolated - 1; - cursor += isolated - 1; - continue; + if (!strict && cc->nr_migratepages <= cc->nr_freepages) { + blockpfn += isolated; + break; } + /* Advance to the end of split page */ + blockpfn += isolated - 1; + cursor += isolated - 1; + continue; isolate_fail: if (strict) @@ -469,6 +520,9 @@ isolate_fail: } + if (locked) + spin_unlock_irqrestore(&cc->zone->lock, flags); + /* * There is a tiny chance that we have read bogus compound_order(), * so be careful to not go outside of the pageblock. @@ -490,9 +544,6 @@ isolate_fail: if (strict && blockpfn < end_pfn) total_isolated = 0; - if (locked) - spin_unlock_irqrestore(&cc->zone->lock, flags); - /* Update the pageblock-skip if the whole pageblock was scanned */ if (blockpfn == end_pfn) update_pageblock_skip(cc, valid_page, total_isolated, false); @@ -570,7 +621,7 @@ isolate_freepages_range(struct compact_control *cc, */ } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(&freelist); if (pfn < end_pfn) { @@ -672,7 +723,6 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, /* Time to isolate some pages for migration */ for (; low_pfn < end_pfn; low_pfn++) { - bool is_lru; if (skip_on_failure && low_pfn >= next_skip_pfn) { /* @@ -735,21 +785,6 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, } /* - * Check may be lockless but that's ok as we recheck later. - * It's possible to migrate LRU pages and balloon pages - * Skip any other type of page - */ - is_lru = PageLRU(page); - if (!is_lru) { - if (unlikely(balloon_page_movable(page))) { - if (balloon_page_isolate(page)) { - /* Successfully isolated */ - goto isolate_success; - } - } - } - - /* * Regardless of being on LRU, compound pages such as THP and * hugetlbfs are not to be compacted. We can potentially save * a lot of iterations if we skip them at once. The check is @@ -765,8 +800,30 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn, goto isolate_fail; } - if (!is_lru) + /* + * Check may be lockless but that's ok as we recheck later. + * It's possible to migrate LRU and non-lru movable pages. + * Skip any other type of page + */ + if (!PageLRU(page)) { + /* + * __PageMovable can return false positive so we need + * to verify it under page_lock. + */ + if (unlikely(__PageMovable(page)) && + !PageIsolated(page)) { + if (locked) { + spin_unlock_irqrestore(&zone->lru_lock, + flags); + locked = false; + } + + if (isolate_movable_page(page, isolate_mode)) + goto isolate_success; + } + goto isolate_fail; + } /* * Migration will fail if an anonymous page is pinned in memory, @@ -1011,7 +1068,6 @@ static void isolate_freepages(struct compact_control *cc) block_end_pfn = block_start_pfn, block_start_pfn -= pageblock_nr_pages, isolate_start_pfn = block_start_pfn) { - /* * This can iterate a massively long zone without finding any * suitable migration targets, so periodically check if we need @@ -1035,36 +1091,34 @@ static void isolate_freepages(struct compact_control *cc) continue; /* Found a block suitable for isolating free pages from. */ - isolate_freepages_block(cc, &isolate_start_pfn, - block_end_pfn, freelist, false); + isolate_freepages_block(cc, &isolate_start_pfn, block_end_pfn, + freelist, false); /* - * If we isolated enough freepages, or aborted due to async - * compaction being contended, terminate the loop. - * Remember where the free scanner should restart next time, - * which is where isolate_freepages_block() left off. - * But if it scanned the whole pageblock, isolate_start_pfn - * now points at block_end_pfn, which is the start of the next - * pageblock. - * In that case we will however want to restart at the start - * of the previous pageblock. + * If we isolated enough freepages, or aborted due to lock + * contention, terminate. */ if ((cc->nr_freepages >= cc->nr_migratepages) || cc->contended) { - if (isolate_start_pfn >= block_end_pfn) + if (isolate_start_pfn >= block_end_pfn) { + /* + * Restart at previous pageblock if more + * freepages can be isolated next time. + */ isolate_start_pfn = block_start_pfn - pageblock_nr_pages; + } break; - } else { + } else if (isolate_start_pfn < block_end_pfn) { /* - * isolate_freepages_block() should not terminate - * prematurely unless contended, or isolated enough + * If isolation failed early, do not continue + * needlessly. */ - VM_BUG_ON(isolate_start_pfn < block_end_pfn); + break; } } - /* split_free_page does not map the pages */ + /* __isolate_free_page() does not map the pages */ map_pages(freelist); /* |