46  * order == -1 is expected when compacting proactively via
51 static inline bool is_via_compact_memory(int order)  in is_via_compact_memory()  argument
53 	return order == -1;  in is_via_compact_memory()
59 static inline bool is_via_compact_memory(int order) { return false; }  in is_via_compact_memory()  argument
67 #define block_start_pfn(pfn, order)	round_down(pfn, 1UL << (order))  argument
68 #define block_end_pfn(pfn, order)	ALIGN((pfn) + 1, 1UL << (order))  argument
71  * Page order with-respect-to which proactive compaction
83 static struct page *mark_allocated_noprof(struct page *page, unsigned int order, gfp_t gfp_flags)  in mark_allocated_noprof()  argument
85 	post_alloc_hook(page, order, __GFP_MOVABLE);  in mark_allocated_noprof()
93 	int order;  in release_free_list()  local
96 	for (order = 0; order < NR_PAGE_ORDERS; order++) {  in release_free_list()
99 		list_for_each_entry_safe(page, next, &freepages[order], lru) {  in release_free_list()
107 			mark_allocated(page, order, __GFP_MOVABLE);  in release_free_list()
108 			__free_pages(page, order);  in release_free_list()
159 static void defer_compaction(struct zone *zone, int order)  in defer_compaction()  argument
164 	if (order < zone->compact_order_failed)  in defer_compaction()
165 		zone->compact_order_failed = order;  in defer_compaction()
170 	trace_mm_compaction_defer_compaction(zone, order);  in defer_compaction()
174 static bool compaction_deferred(struct zone *zone, int order)  in compaction_deferred()  argument
178 	if (order < zone->compact_order_failed)  in compaction_deferred()
187 	trace_mm_compaction_deferred(zone, order);  in compaction_deferred()
193  * Update defer tracking counters after successful compaction of given order,
197 void compaction_defer_reset(struct zone *zone, int order,  in compaction_defer_reset()  argument
204 	if (order >= zone->compact_order_failed)  in compaction_defer_reset()
205 		zone->compact_order_failed = order + 1;  in compaction_defer_reset()
207 	trace_mm_compaction_defer_reset(zone, order);  in compaction_defer_reset()
211 static bool compaction_restarting(struct zone *zone, int order)  in compaction_restarting()  argument
213 	if (order < zone->compact_order_failed)  in compaction_restarting()
292  * released. It is always pointless to compact pages of such order (if they are
601 	unsigned int order;  in isolate_freepages_block()  local
632 			const unsigned int order = compound_order(page);  in isolate_freepages_block()  local
634 			if ((order <= MAX_PAGE_ORDER) &&  in isolate_freepages_block()
635 			    (blockpfn + (1UL << order) <= end_pfn)) {  in isolate_freepages_block()
636 				blockpfn += (1UL << order) - 1;  in isolate_freepages_block()
637 				page += (1UL << order) - 1;  in isolate_freepages_block()
638 				nr_scanned += (1UL << order) - 1;  in isolate_freepages_block()
657 		/* Found a free page, will break it into order-0 pages */  in isolate_freepages_block()
658 		order = buddy_order(page);  in isolate_freepages_block()
659 		isolated = __isolate_free_page(page, order);  in isolate_freepages_block()
662 		set_page_private(page, order);  in isolate_freepages_block()
667 		list_add_tail(&page->lru, &freelist[order]);  in isolate_freepages_block()
732 	int order;  in isolate_freepages_range()  local
734 	for (order = 0; order < NR_PAGE_ORDERS; order++)  in isolate_freepages_range()
735 		INIT_LIST_HEAD(&cc->freepages[order]);  in isolate_freepages_range()
751 		 * is more than pageblock order. In this case, we adjust  in isolate_freepages_range()
778 		 * pageblock_nr_pages for some non-negative n.  (Max order  in isolate_freepages_range()
828  *			       folio order and compaction target order
829  * @order:		to-be-isolated folio order
830  * @target_order:	compaction target order
834 static bool skip_isolation_on_order(int order, int target_order)  in skip_isolation_on_order()  argument
839 	 * target order: we wouldn't be here if we'd have a free folio with  in skip_isolation_on_order()
843 	if (!is_via_compact_memory(target_order) && order >= target_order)  in skip_isolation_on_order()
849 	return order >= pageblock_order;  in skip_isolation_on_order()
913 		next_skip_pfn = block_end_pfn(low_pfn, cc->order);  in isolate_migratepages_block()
923 			 * previous order-aligned block, and did not skip it due  in isolate_migratepages_block()
931 			 * We failed to isolate in the previous order-aligned  in isolate_migratepages_block()
934 			 * next_skip_pfn by 1 << order, as low_pfn might have  in isolate_migratepages_block()
936 			 * a compound or a high-order buddy page in the  in isolate_migratepages_block()
939 			next_skip_pfn = block_end_pfn(low_pfn, cc->order);  in isolate_migratepages_block()
984 			const unsigned int order = compound_order(page);  in isolate_migratepages_block()  local
987 			 * bigger than its order. THPs and other compound pages  in isolate_migratepages_block()
992 				if (order <= MAX_PAGE_ORDER) {  in isolate_migratepages_block()
993 					low_pfn += (1UL << order) - 1;  in isolate_migratepages_block()
994 					nr_scanned += (1UL << order) - 1;  in isolate_migratepages_block()
1014 				low_pfn += (1UL << order) - 1;  in isolate_migratepages_block()
1015 				nr_scanned += (1UL << order) - 1;  in isolate_migratepages_block()
1038 		 * Skip if free. We read page order here without zone lock  in isolate_migratepages_block()
1048 			 * a valid page order. Consider only values in the  in isolate_migratepages_block()
1049 			 * valid order range to prevent low_pfn overflow.  in isolate_migratepages_block()
1067 			const unsigned int order = compound_order(page);  in isolate_migratepages_block()  local
1069 			/* Skip based on page order and compaction target order. */  in isolate_migratepages_block()
1070 			if (skip_isolation_on_order(order, cc->order)) {  in isolate_migratepages_block()
1071 				if (order <= MAX_PAGE_ORDER) {  in isolate_migratepages_block()
1072 					low_pfn += (1UL << order) - 1;  in isolate_migratepages_block()
1073 					nr_scanned += (1UL << order) - 1;  in isolate_migratepages_block()
1219 			 * Check LRU folio order under the lock  in isolate_migratepages_block()
1222 							     cc->order) &&  in isolate_migratepages_block()
1276 		 * instead of migrating, as we cannot form the cc->order buddy  in isolate_migratepages_block()
1295 			next_skip_pfn += 1UL << cc->order;  in isolate_migratepages_block()
1420 		int order = cc->order > 0 ? cc->order : pageblock_order;  in suitable_migration_target()  local
1425 		 * pageblock, so it's not worth to check order for valid range.  in suitable_migration_target()
1427 		if (buddy_order_unsafe(page) >= order)  in suitable_migration_target()
1523 static int next_search_order(struct compact_control *cc, int order)  in next_search_order()  argument
1525 	order--;  in next_search_order()
1526 	if (order < 0)  in next_search_order()
1527 		order = cc->order - 1;  in next_search_order()
1530 	if (order == cc->search_order) {  in next_search_order()
1533 			cc->search_order = cc->order - 1;  in next_search_order()
1537 	return order;  in next_search_order()
1549 	int order;  in fast_isolate_freepages()  local
1551 	/* Full compaction passes in a negative order */  in fast_isolate_freepages()
1552 	if (cc->order <= 0)  in fast_isolate_freepages()
1576 	 * Search starts from the last successful isolation order or the next  in fast_isolate_freepages()
1577 	 * order to search after a previous failure  in fast_isolate_freepages()
1579 	cc->search_order = min_t(unsigned int, cc->order - 1, cc->search_order);  in fast_isolate_freepages()
1581 	for (order = cc->search_order;  in fast_isolate_freepages()
1582 	     !page && order >= 0;  in fast_isolate_freepages()
1583 	     order = next_search_order(cc, order)) {  in fast_isolate_freepages()
1584 		struct free_area *area = &cc->zone->free_area[order];  in fast_isolate_freepages()
1609 				cc->search_order = order;  in fast_isolate_freepages()
1638 			if (__isolate_free_page(page, order)) {  in fast_isolate_freepages()
1639 				set_page_private(page, order);  in fast_isolate_freepages()
1640 				nr_isolated = 1 << order;  in fast_isolate_freepages()
1644 				list_add_tail(&page->lru, &cc->freepages[order]);  in fast_isolate_freepages()
1648 				order = cc->search_order + 1;  in fast_isolate_freepages()
1660 		 * Smaller scan on next order so the total scan is related  in fast_isolate_freepages()
1837 	int order = folio_order(src);  in compaction_alloc_noprof()  local
1844 	for (start_order = order; start_order < NR_PAGE_ORDERS; start_order++)  in compaction_alloc_noprof()
1863 	while (start_order > order) {  in compaction_alloc_noprof()
1872 	post_alloc_hook(&dst->page, order, __GFP_MOVABLE);  in compaction_alloc_noprof()
1874 	if (order)  in compaction_alloc_noprof()
1875 		prep_compound_page(&dst->page, order);  in compaction_alloc_noprof()
1876 	cc->nr_freepages -= 1 << order;  in compaction_alloc_noprof()
1877 	cc->nr_migratepages -= 1 << order;  in compaction_alloc_noprof()
1894 	int order = folio_order(dst);  in compaction_free()  local
1898 		free_pages_prepare(page, order);  in compaction_free()
1899 		list_add(&dst->lru, &cc->freepages[order]);  in compaction_free()
1900 		cc->nr_freepages += 1 << order;  in compaction_free()
1902 	cc->nr_migratepages += 1 << order;  in compaction_free()
1966 	int order;  in fast_find_migrateblock()  local
1993 	if (cc->order <= PAGE_ALLOC_COSTLY_ORDER)  in fast_find_migrateblock()
2016 	for (order = cc->order - 1;  in fast_find_migrateblock()
2017 	     order >= PAGE_ALLOC_COSTLY_ORDER && !found_block && nr_scanned < limit;  in fast_find_migrateblock()
2018 	     order--) {  in fast_find_migrateblock()
2019 		struct free_area *area = &cc->zone->free_area[order];  in fast_find_migrateblock()
2276 	unsigned int order;  in __compact_finished()  local
2319 	if (is_via_compact_memory(cc->order))  in __compact_finished()
2333 	for (order = cc->order; order < NR_PAGE_ORDERS; order++) {  in __compact_finished()
2334 		struct free_area *area = &cc->zone->free_area[order];  in __compact_finished()
2351 		if (find_suitable_fallback(area, order, migratetype,  in __compact_finished()
2376 	trace_mm_compaction_finished(cc->zone, cc->order, ret);  in compact_finished()
2383 static bool __compaction_suitable(struct zone *zone, int order,  in __compaction_suitable()  argument
2389 	 * Watermarks for order-0 must be met for compaction to be able to  in __compaction_suitable()
2402 	watermark = (order > PAGE_ALLOC_COSTLY_ORDER) ?  in __compaction_suitable()
2404 	watermark += compact_gap(order);  in __compaction_suitable()
2412 bool compaction_suitable(struct zone *zone, int order, int highest_zoneidx)  in compaction_suitable()  argument
2417 	suitable = __compaction_suitable(zone, order, highest_zoneidx,  in compaction_suitable()
2424 	 * watermarks, but we already failed the high-order watermark check  in compaction_suitable()
2437 		if (order > PAGE_ALLOC_COSTLY_ORDER) {  in compaction_suitable()
2438 			int fragindex = fragmentation_index(zone, order);  in compaction_suitable()
2450 	trace_mm_compaction_suitable(zone, order, compact_result);  in compaction_suitable()
2455 bool compaction_zonelist_suitable(struct alloc_context *ac, int order,  in compaction_zonelist_suitable()  argument
2471 		 * want to trash just for a single high order allocation which  in compaction_zonelist_suitable()
2475 		available = zone_reclaimable_pages(zone) / order;  in compaction_zonelist_suitable()
2477 		if (__compaction_suitable(zone, order, ac->highest_zoneidx,  in compaction_zonelist_suitable()
2486  * Should we do compaction for target allocation order.
2487  * Return COMPACT_SUCCESS if allocation for target order can be already
2489  * Return COMPACT_SKIPPED if compaction for target order is likely to fail
2490  * Return COMPACT_CONTINUE if compaction for target order should be ran
2493 compaction_suit_allocation_order(struct zone *zone, unsigned int order,  in compaction_suit_allocation_order()  argument
2500 	if (zone_watermark_ok(zone, order, watermark, highest_zoneidx,  in compaction_suit_allocation_order()
2507 	 * the high-order page in CMA pageblocks, which would not help the  in compaction_suit_allocation_order()
2508 	 * allocation to succeed. However, limit the check to costly order async  in compaction_suit_allocation_order()
2513 	if (order > PAGE_ALLOC_COSTLY_ORDER && async &&  in compaction_suit_allocation_order()
2515 		watermark = low_wmark_pages(zone) + compact_gap(order);  in compaction_suit_allocation_order()
2521 	if (!compaction_suitable(zone, order, highest_zoneidx))  in compaction_suit_allocation_order()
2537 	int order;  in compact_zone()  local
2547 	for (order = 0; order < NR_PAGE_ORDERS; order++)  in compact_zone()
2548 		INIT_LIST_HEAD(&cc->freepages[order]);  in compact_zone()
2553 	if (!is_via_compact_memory(cc->order)) {  in compact_zone()
2554 		ret = compaction_suit_allocation_order(cc->zone, cc->order,  in compact_zone()
2566 	if (compaction_restarting(cc->zone, cc->order))  in compact_zone()
2648 			 * previous cc->order aligned block.  in compact_zone()
2702 				if (cc->order == COMPACTION_HPAGE_ORDER)  in compact_zone()
2718 		 * cc->order aligned block where we migrated from? If yes,  in compact_zone()
2723 		if (cc->order > 0 && last_migrated_pfn) {  in compact_zone()
2725 				block_start_pfn(cc->migrate_pfn, cc->order);  in compact_zone()
2765 static enum compact_result compact_zone_order(struct zone *zone, int order,  in compact_zone_order()  argument
2772 		.order = order,  in compact_zone_order()
2773 		.search_order = order,  in compact_zone_order()
2820  * try_to_compact_pages - Direct compact to satisfy a high-order allocation
2822  * @order: The order of the current allocation
2830 enum compact_result try_to_compact_pages(gfp_t gfp_mask, unsigned int order,  in try_to_compact_pages()  argument
2841 	trace_mm_compaction_try_to_compact_pages(order, gfp_mask, prio);  in try_to_compact_pages()
2854 					&& compaction_deferred(zone, order)) {  in try_to_compact_pages()
2859 		status = compact_zone_order(zone, order, gfp_mask, prio,  in try_to_compact_pages()
2871 			compaction_defer_reset(zone, order, false);  in try_to_compact_pages()
2883 			defer_compaction(zone, order);  in try_to_compact_pages()
2914 		.order = -1,  in compact_node()
3073 	 * order is allocatable.  in kcompactd_do_work()
3078 		.order = pgdat->kcompactd_max_order,  in kcompactd_do_work()
3087 	trace_mm_compaction_kcompactd_wake(pgdat->node_id, cc.order,  in kcompactd_do_work()
3098 		if (compaction_deferred(zone, cc.order))  in kcompactd_do_work()
3102 				cc.order, zoneid, ALLOC_WMARK_MIN,  in kcompactd_do_work()
3114 			compaction_defer_reset(zone, cc.order, false);  in kcompactd_do_work()
3119 			 * order >= cc.order.  This is ratelimited by the  in kcompactd_do_work()
3128 			defer_compaction(zone, cc.order);  in kcompactd_do_work()
3139 	 * the requested order/highest_zoneidx in case it was higher/tighter  in kcompactd_do_work()
3142 	if (pgdat->kcompactd_max_order <= cc.order)  in kcompactd_do_work()
3148 void wakeup_kcompactd(pg_data_t *pgdat, int order, int highest_zoneidx)  in wakeup_kcompactd()  argument
3150 	if (!order)  in wakeup_kcompactd()
3153 	if (pgdat->kcompactd_max_order < order)  in wakeup_kcompactd()
3154 		pgdat->kcompactd_max_order = order;  in wakeup_kcompactd()
3169 	trace_mm_compaction_wakeup_kcompactd(pgdat->node_id, order,  in wakeup_kcompactd()