[PATCH v5 6/6] mm/page_isolation: remove migratetype parameter from more functions.

Zi Yan posted 6 patches 7 months ago
There is a newer version of this series
[PATCH v5 6/6] mm/page_isolation: remove migratetype parameter from more functions.
Posted by Zi Yan 7 months ago
migratetype is no longer overwritten during pageblock isolation,
start_isolate_page_range(), has_unmovable_pages(), and
set_migratetype_isolate() no longer need which migratetype to restore
during isolation failure.

For has_unmoable_pages(), it needs to know if the isolation is for CMA
allocation, so adding CMA_ALLOCATION to provide the information. At the
same time change isolation flags to enum pb_isolate_mode (MEMORY_OFFLINE,
CMA_ALLOCATION, and ISOLATE_MODE_OTHERS). Remove REPORT_FAILURE and check
MEMORY_OFFLINE instead, since only MEMORY_OFFLINE reports isolation
failures.

alloc_contig_range() no longer needs migratetype. Replace it with
a newly defined acr_flags_t to tell if an allocation is for CMA. So does
__alloc_contig_migrate_range().

Signed-off-by: Zi Yan <ziy@nvidia.com>
---
 drivers/virtio/virtio_mem.c    |  3 +-
 include/linux/gfp.h            |  6 ++-
 include/linux/page-isolation.h | 19 ++++++++--
 include/trace/events/kmem.h    | 14 ++++---
 mm/cma.c                       |  2 +-
 mm/memory_hotplug.c            |  4 +-
 mm/page_alloc.c                | 25 ++++++-------
 mm/page_isolation.c            | 67 +++++++++++++++-------------------
 8 files changed, 72 insertions(+), 68 deletions(-)

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 56d0dbe62163..8accc0f255a8 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -1243,8 +1243,7 @@ static int virtio_mem_fake_offline(struct virtio_mem *vm, unsigned long pfn,
 		if (atomic_read(&vm->config_changed))
 			return -EAGAIN;
 
-		rc = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE,
-					GFP_KERNEL);
+		rc = alloc_contig_range(pfn, pfn + nr_pages, 0, GFP_KERNEL);
 		if (rc == -ENOMEM)
 			/* whoops, out of memory */
 			return rc;
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index be160e8d8bcb..dea27ed24f8e 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -423,9 +423,13 @@ static inline bool gfp_compaction_allowed(gfp_t gfp_mask)
 extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
 
 #ifdef CONFIG_CONTIG_ALLOC
+
+typedef unsigned int __bitwise acr_flags_t;
+#define ACR_CMA		((__force acr_flags_t)BIT(0))	// allocate for CMA
+
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range_noprof(unsigned long start, unsigned long end,
-			      unsigned migratetype, gfp_t gfp_mask);
+			      acr_flags_t alloc_flags, gfp_t gfp_mask);
 #define alloc_contig_range(...)			alloc_hooks(alloc_contig_range_noprof(__VA_ARGS__))
 
 extern struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 7a681a49e73c..b61bca909ddc 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -38,8 +38,19 @@ static inline void set_pageblock_isolate(struct page *page)
 }
 #endif
 
-#define MEMORY_OFFLINE	0x1
-#define REPORT_FAILURE	0x2
+/*
+ * Pageblock isolation modes:
+ * MEMORY_OFFLINE      - isolate to offline (!allocate) memory e.g., skip over
+ *		         PageHWPoison() pages and PageOffline() pages.
+ *		         Unmovable pages will be reported in this mode.
+ * CMA_ALLOCATION      - isolate for CMA allocations
+ * ISOLATE_MODE_OTHERS - isolate for other purposes
+ */
+enum pb_isolate_mode {
+	MEMORY_OFFLINE,
+	CMA_ALLOCATION,
+	ISOLATE_MODE_OTHERS,
+};
 
 void __meminit init_pageblock_migratetype(struct page *page,
 					  enum migratetype migratetype,
@@ -49,10 +60,10 @@ bool pageblock_isolate_and_move_free_pages(struct zone *zone, struct page *page)
 bool pageblock_unisolate_and_move_free_pages(struct zone *zone, struct page *page);
 
 int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
-			     int migratetype, int flags);
+			     enum pb_isolate_mode mode);
 
 void undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn);
 
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
-			int isol_flags);
+			enum pb_isolate_mode mode);
 #endif
diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
index f74925a6cf69..efffcf578217 100644
--- a/include/trace/events/kmem.h
+++ b/include/trace/events/kmem.h
@@ -304,6 +304,7 @@ TRACE_EVENT(mm_page_alloc_extfrag,
 		__entry->change_ownership)
 );
 
+#ifdef CONFIG_CONTIG_ALLOC
 TRACE_EVENT(mm_alloc_contig_migrate_range_info,
 
 	TP_PROTO(unsigned long start,
@@ -311,9 +312,9 @@ TRACE_EVENT(mm_alloc_contig_migrate_range_info,
 		 unsigned long nr_migrated,
 		 unsigned long nr_reclaimed,
 		 unsigned long nr_mapped,
-		 int migratetype),
+		 acr_flags_t alloc_flags),
 
-	TP_ARGS(start, end, nr_migrated, nr_reclaimed, nr_mapped, migratetype),
+	TP_ARGS(start, end, nr_migrated, nr_reclaimed, nr_mapped, alloc_flags),
 
 	TP_STRUCT__entry(
 		__field(unsigned long, start)
@@ -321,7 +322,7 @@ TRACE_EVENT(mm_alloc_contig_migrate_range_info,
 		__field(unsigned long, nr_migrated)
 		__field(unsigned long, nr_reclaimed)
 		__field(unsigned long, nr_mapped)
-		__field(int, migratetype)
+		__field(acr_flags_t, alloc_flags)
 	),
 
 	TP_fast_assign(
@@ -330,17 +331,18 @@ TRACE_EVENT(mm_alloc_contig_migrate_range_info,
 		__entry->nr_migrated = nr_migrated;
 		__entry->nr_reclaimed = nr_reclaimed;
 		__entry->nr_mapped = nr_mapped;
-		__entry->migratetype = migratetype;
+		__entry->alloc_flags = alloc_flags;
 	),
 
-	TP_printk("start=0x%lx end=0x%lx migratetype=%d nr_migrated=%lu nr_reclaimed=%lu nr_mapped=%lu",
+	TP_printk("start=0x%lx end=0x%lx alloc_flags=%d nr_migrated=%lu nr_reclaimed=%lu nr_mapped=%lu",
 		  __entry->start,
 		  __entry->end,
-		  __entry->migratetype,
+		  __entry->alloc_flags,
 		  __entry->nr_migrated,
 		  __entry->nr_reclaimed,
 		  __entry->nr_mapped)
 );
+#endif
 
 TRACE_EVENT(mm_setup_per_zone_wmarks,
 
diff --git a/mm/cma.c b/mm/cma.c
index 397567883a10..9ee8fad797bc 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -822,7 +822,7 @@ static int cma_range_alloc(struct cma *cma, struct cma_memrange *cmr,
 
 		pfn = cmr->base_pfn + (bitmap_no << cma->order_per_bit);
 		mutex_lock(&cma->alloc_mutex);
-		ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, gfp);
+		ret = alloc_contig_range(pfn, pfn + count, ACR_CMA, gfp);
 		mutex_unlock(&cma->alloc_mutex);
 		if (ret == 0) {
 			page = pfn_to_page(pfn);
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index ab66acd3e6b3..44f140dee0ce 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -2008,9 +2008,7 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages,
 	lru_cache_disable();
 
 	/* set above range as isolated */
-	ret = start_isolate_page_range(start_pfn, end_pfn,
-				       MIGRATE_MOVABLE,
-				       MEMORY_OFFLINE | REPORT_FAILURE);
+	ret = start_isolate_page_range(start_pfn, end_pfn, MEMORY_OFFLINE);
 	if (ret) {
 		reason = "failure to isolate range";
 		goto failed_removal_pcplists_disabled;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 499c3f40851f..48f458f7143a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6720,11 +6720,12 @@ static void alloc_contig_dump_pages(struct list_head *page_list)
 
 /*
  * [start, end) must belong to a single zone.
- * @migratetype: using migratetype to filter the type of migration in
+ * @alloc_flags: using acr_flags_t to filter the type of migration in
  *		trace_mm_alloc_contig_migrate_range_info.
  */
 static int __alloc_contig_migrate_range(struct compact_control *cc,
-		unsigned long start, unsigned long end, int migratetype)
+					unsigned long start, unsigned long end,
+					acr_flags_t alloc_flags)
 {
 	/* This function is based on compact_zone() from compaction.c. */
 	unsigned int nr_reclaimed;
@@ -6796,7 +6797,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
 		putback_movable_pages(&cc->migratepages);
 	}
 
-	trace_mm_alloc_contig_migrate_range_info(start, end, migratetype,
+	trace_mm_alloc_contig_migrate_range_info(start, end, alloc_flags,
 						 total_migrated,
 						 total_reclaimed,
 						 total_mapped);
@@ -6867,10 +6868,7 @@ static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask)
  * alloc_contig_range() -- tries to allocate given range of pages
  * @start:	start PFN to allocate
  * @end:	one-past-the-last PFN to allocate
- * @migratetype:	migratetype of the underlying pageblocks (either
- *			#MIGRATE_MOVABLE or #MIGRATE_CMA).  All pageblocks
- *			in range must have the same migratetype and it must
- *			be either of the two.
+ * @alloc_flags:	allocation information
  * @gfp_mask:	GFP mask. Node/zone/placement hints are ignored; only some
  *		action and reclaim modifiers are supported. Reclaim modifiers
  *		control allocation behavior during compaction/migration/reclaim.
@@ -6887,7 +6885,7 @@ static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask)
  * need to be freed with free_contig_range().
  */
 int alloc_contig_range_noprof(unsigned long start, unsigned long end,
-		       unsigned migratetype, gfp_t gfp_mask)
+			acr_flags_t alloc_flags, gfp_t gfp_mask)
 {
 	unsigned long outer_start, outer_end;
 	int ret = 0;
@@ -6903,6 +6901,8 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
 	};
 	INIT_LIST_HEAD(&cc.migratepages);
 	bool is_range_aligned;
+	isolate_mode_t mode = (alloc_flags & ACR_CMA) ? CMA_ALLOCATION :
+							ISOLATE_MODE_OTHERS;
 
 	gfp_mask = current_gfp_context(gfp_mask);
 	if (__alloc_contig_verify_gfp_mask(gfp_mask, (gfp_t *)&cc.gfp_mask))
@@ -6929,7 +6929,7 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
 	 * put back to page allocator so that buddy can use them.
 	 */
 
-	ret = start_isolate_page_range(start, end, migratetype, 0);
+	ret = start_isolate_page_range(start, end, mode);
 	if (ret)
 		goto done;
 
@@ -6945,7 +6945,7 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
 	 * allocated.  So, if we fall through be sure to clear ret so that
 	 * -EBUSY is not accidentally used or returned to caller.
 	 */
-	ret = __alloc_contig_migrate_range(&cc, start, end, migratetype);
+	ret = __alloc_contig_migrate_range(&cc, start, end, alloc_flags);
 	if (ret && ret != -EBUSY)
 		goto done;
 
@@ -6979,7 +6979,7 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
 	outer_start = find_large_buddy(start);
 
 	/* Make sure the range is really isolated. */
-	if (test_pages_isolated(outer_start, end, 0)) {
+	if (test_pages_isolated(outer_start, end, mode)) {
 		ret = -EBUSY;
 		goto done;
 	}
@@ -7037,8 +7037,7 @@ static int __alloc_contig_pages(unsigned long start_pfn,
 {
 	unsigned long end_pfn = start_pfn + nr_pages;
 
-	return alloc_contig_range_noprof(start_pfn, end_pfn, MIGRATE_MOVABLE,
-				   gfp_mask);
+	return alloc_contig_range_noprof(start_pfn, end_pfn, 0, gfp_mask);
 }
 
 static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 1edfef408faf..bcf6525ea238 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -31,7 +31,7 @@
  *
  */
 static struct page *has_unmovable_pages(unsigned long start_pfn, unsigned long end_pfn,
-				int migratetype, int flags)
+				enum pb_isolate_mode mode)
 {
 	struct page *page = pfn_to_page(start_pfn);
 	struct zone *zone = page_zone(page);
@@ -46,7 +46,7 @@ static struct page *has_unmovable_pages(unsigned long start_pfn, unsigned long e
 		 * isolate CMA pageblocks even when they are not movable in fact
 		 * so consider them movable here.
 		 */
-		if (is_migrate_cma(migratetype))
+		if (mode == CMA_ALLOCATION)
 			return NULL;
 
 		return page;
@@ -117,7 +117,7 @@ static struct page *has_unmovable_pages(unsigned long start_pfn, unsigned long e
 		 * The HWPoisoned page may be not in buddy system, and
 		 * page_count() is not 0.
 		 */
-		if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
+		if ((mode == MEMORY_OFFLINE) && PageHWPoison(page))
 			continue;
 
 		/*
@@ -130,7 +130,7 @@ static struct page *has_unmovable_pages(unsigned long start_pfn, unsigned long e
 		 * move these pages that still have a reference count > 0.
 		 * (false negatives in this function only)
 		 */
-		if ((flags & MEMORY_OFFLINE) && PageOffline(page))
+		if ((mode == MEMORY_OFFLINE) && PageOffline(page))
 			continue;
 
 		if (__PageMovable(page) || PageLRU(page))
@@ -151,7 +151,7 @@ static struct page *has_unmovable_pages(unsigned long start_pfn, unsigned long e
  * present in [start_pfn, end_pfn). The pageblock must intersect with
  * [start_pfn, end_pfn).
  */
-static int set_migratetype_isolate(struct page *page, int migratetype, int isol_flags,
+static int set_migratetype_isolate(struct page *page, enum pb_isolate_mode mode,
 			unsigned long start_pfn, unsigned long end_pfn)
 {
 	struct zone *zone = page_zone(page);
@@ -186,7 +186,7 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
 				  end_pfn);
 
 	unmovable = has_unmovable_pages(check_unmovable_start, check_unmovable_end,
-			migratetype, isol_flags);
+			mode);
 	if (!unmovable) {
 		if (!pageblock_isolate_and_move_free_pages(zone, page)) {
 			spin_unlock_irqrestore(&zone->lock, flags);
@@ -198,7 +198,7 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_
 	}
 
 	spin_unlock_irqrestore(&zone->lock, flags);
-	if (isol_flags & REPORT_FAILURE) {
+	if (mode == MEMORY_OFFLINE) {
 		/*
 		 * printk() with zone->lock held will likely trigger a
 		 * lockdep splat, so defer it here.
@@ -292,11 +292,10 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
  * isolate_single_pageblock() -- tries to isolate a pageblock that might be
  * within a free or in-use page.
  * @boundary_pfn:		pageblock-aligned pfn that a page might cross
- * @flags:			isolation flags
+ * @mode:			isolation mode
  * @isolate_before:	isolate the pageblock before the boundary_pfn
  * @skip_isolation:	the flag to skip the pageblock isolation in second
  *			isolate_single_pageblock()
- * @migratetype:	migrate type to set in error recovery.
  *
  * Free and in-use pages can be as big as MAX_PAGE_ORDER and contain more than one
  * pageblock. When not all pageblocks within a page are isolated at the same
@@ -311,8 +310,9 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
  * either. The function handles this by splitting the free page or migrating
  * the in-use page then splitting the free page.
  */
-static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
-		bool isolate_before, bool skip_isolation, int migratetype)
+static int isolate_single_pageblock(unsigned long boundary_pfn,
+			enum pb_isolate_mode mode, bool isolate_before,
+			bool skip_isolation)
 {
 	unsigned long start_pfn;
 	unsigned long isolate_pageblock;
@@ -338,12 +338,11 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
 				      zone->zone_start_pfn);
 
 	if (skip_isolation) {
-		int mt __maybe_unused = get_pageblock_migratetype(pfn_to_page(isolate_pageblock));
-
-		VM_BUG_ON(!is_migrate_isolate(mt));
+		VM_BUG_ON(!get_pageblock_isolate(pfn_to_page(isolate_pageblock)));
 	} else {
-		ret = set_migratetype_isolate(pfn_to_page(isolate_pageblock), migratetype,
-				flags, isolate_pageblock, isolate_pageblock + pageblock_nr_pages);
+		ret = set_migratetype_isolate(pfn_to_page(isolate_pageblock),
+				mode, isolate_pageblock,
+				isolate_pageblock + pageblock_nr_pages);
 
 		if (ret)
 			return ret;
@@ -441,14 +440,7 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
  * start_isolate_page_range() - mark page range MIGRATE_ISOLATE
  * @start_pfn:		The first PFN of the range to be isolated.
  * @end_pfn:		The last PFN of the range to be isolated.
- * @migratetype:	Migrate type to set in error recovery.
- * @flags:		The following flags are allowed (they can be combined in
- *			a bit mask)
- *			MEMORY_OFFLINE - isolate to offline (!allocate) memory
- *					 e.g., skip over PageHWPoison() pages
- *					 and PageOffline() pages.
- *			REPORT_FAILURE - report details about the failure to
- *			isolate the range
+ * @mode:		isolation mode
  *
  * Making page-allocation-type to be MIGRATE_ISOLATE means free pages in
  * the range will never be allocated. Any free pages and pages freed in the
@@ -481,7 +473,7 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
  * Return: 0 on success and -EBUSY if any part of range cannot be isolated.
  */
 int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
-			     int migratetype, int flags)
+			     enum pb_isolate_mode mode)
 {
 	unsigned long pfn;
 	struct page *page;
@@ -492,8 +484,8 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 	bool skip_isolation = false;
 
 	/* isolate [isolate_start, isolate_start + pageblock_nr_pages) pageblock */
-	ret = isolate_single_pageblock(isolate_start, flags, false,
-			skip_isolation, migratetype);
+	ret = isolate_single_pageblock(isolate_start, mode, false,
+			skip_isolation);
 	if (ret)
 		return ret;
 
@@ -501,8 +493,7 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 		skip_isolation = true;
 
 	/* isolate [isolate_end - pageblock_nr_pages, isolate_end) pageblock */
-	ret = isolate_single_pageblock(isolate_end, flags, true,
-			skip_isolation, migratetype);
+	ret = isolate_single_pageblock(isolate_end, mode, true, skip_isolation);
 	if (ret) {
 		unset_migratetype_isolate(pfn_to_page(isolate_start));
 		return ret;
@@ -513,8 +504,8 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 	     pfn < isolate_end - pageblock_nr_pages;
 	     pfn += pageblock_nr_pages) {
 		page = __first_valid_page(pfn, pageblock_nr_pages);
-		if (page && set_migratetype_isolate(page, migratetype, flags,
-					start_pfn, end_pfn)) {
+		if (page && set_migratetype_isolate(page, mode, start_pfn,
+					end_pfn)) {
 			undo_isolate_page_range(isolate_start, pfn);
 			unset_migratetype_isolate(
 				pfn_to_page(isolate_end - pageblock_nr_pages));
@@ -556,7 +547,7 @@ void undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn)
  */
 static unsigned long
 __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
-				  int flags)
+				  enum pb_isolate_mode mode)
 {
 	struct page *page;
 
@@ -569,10 +560,10 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
 			 * simple way to verify that as VM_BUG_ON(), though.
 			 */
 			pfn += 1 << buddy_order(page);
-		else if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
+		else if ((mode == MEMORY_OFFLINE) && PageHWPoison(page))
 			/* A HWPoisoned page cannot be also PageBuddy */
 			pfn++;
-		else if ((flags & MEMORY_OFFLINE) && PageOffline(page) &&
+		else if ((mode == MEMORY_OFFLINE) && PageOffline(page) &&
 			 !page_count(page))
 			/*
 			 * The responsible driver agreed to skip PageOffline()
@@ -591,11 +582,11 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
  * test_pages_isolated - check if pageblocks in range are isolated
  * @start_pfn:		The first PFN of the isolated range
  * @end_pfn:		The first PFN *after* the isolated range
- * @isol_flags:		Testing mode flags
+ * @mode:		Testing mode
  *
  * This tests if all in the specified range are free.
  *
- * If %MEMORY_OFFLINE is specified in @flags, it will consider
+ * If %MEMORY_OFFLINE is specified in @mode, it will consider
  * poisoned and offlined pages free as well.
  *
  * Caller must ensure the requested range doesn't span zones.
@@ -603,7 +594,7 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
  * Returns 0 if true, -EBUSY if one or more pages are in use.
  */
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
-			int isol_flags)
+			enum pb_isolate_mode mode)
 {
 	unsigned long pfn, flags;
 	struct page *page;
@@ -639,7 +630,7 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
 	/* Check all pages are free or marked as ISOLATED */
 	zone = page_zone(page);
 	spin_lock_irqsave(&zone->lock, flags);
-	pfn = __test_page_isolated_in_pageblock(start_pfn, end_pfn, isol_flags);
+	pfn = __test_page_isolated_in_pageblock(start_pfn, end_pfn, mode);
 	spin_unlock_irqrestore(&zone->lock, flags);
 
 	ret = pfn < end_pfn ? -EBUSY : 0;
-- 
2.47.2
Re: [PATCH v5 6/6] mm/page_isolation: remove migratetype parameter from more functions.
Posted by Vlastimil Babka 6 months, 3 weeks ago
On 5/23/25 21:12, Zi Yan wrote:
> migratetype is no longer overwritten during pageblock isolation,
> start_isolate_page_range(), has_unmovable_pages(), and
> set_migratetype_isolate() no longer need which migratetype to restore
> during isolation failure.
> 
> For has_unmoable_pages(), it needs to know if the isolation is for CMA
> allocation, so adding CMA_ALLOCATION to provide the information. At the
> same time change isolation flags to enum pb_isolate_mode (MEMORY_OFFLINE,
> CMA_ALLOCATION, and ISOLATE_MODE_OTHERS). Remove REPORT_FAILURE and check
> MEMORY_OFFLINE instead, since only MEMORY_OFFLINE reports isolation
> failures.
> 
> alloc_contig_range() no longer needs migratetype. Replace it with
> a newly defined acr_flags_t to tell if an allocation is for CMA. So does
> __alloc_contig_migrate_range().
> 
> Signed-off-by: Zi Yan <ziy@nvidia.com>
> ---
>  drivers/virtio/virtio_mem.c    |  3 +-
>  include/linux/gfp.h            |  6 ++-
>  include/linux/page-isolation.h | 19 ++++++++--
>  include/trace/events/kmem.h    | 14 ++++---
>  mm/cma.c                       |  2 +-
>  mm/memory_hotplug.c            |  4 +-
>  mm/page_alloc.c                | 25 ++++++-------
>  mm/page_isolation.c            | 67 +++++++++++++++-------------------
>  8 files changed, 72 insertions(+), 68 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
> index 56d0dbe62163..8accc0f255a8 100644
> --- a/drivers/virtio/virtio_mem.c
> +++ b/drivers/virtio/virtio_mem.c
> @@ -1243,8 +1243,7 @@ static int virtio_mem_fake_offline(struct virtio_mem *vm, unsigned long pfn,
>  		if (atomic_read(&vm->config_changed))
>  			return -EAGAIN;
>  
> -		rc = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE,
> -					GFP_KERNEL);
> +		rc = alloc_contig_range(pfn, pfn + nr_pages, 0, GFP_KERNEL);
>  		if (rc == -ENOMEM)
>  			/* whoops, out of memory */
>  			return rc;
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index be160e8d8bcb..dea27ed24f8e 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -423,9 +423,13 @@ static inline bool gfp_compaction_allowed(gfp_t gfp_mask)
>  extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
>  
>  #ifdef CONFIG_CONTIG_ALLOC
> +
> +typedef unsigned int __bitwise acr_flags_t;
> +#define ACR_CMA		((__force acr_flags_t)BIT(0))	// allocate for CMA

Would it make sense to define ACR_NONE as 0 so it's more descriptive than
seeing 0 somewhere?

> +
>  /* The below functions must be run on a range from a single zone. */
>  extern int alloc_contig_range_noprof(unsigned long start, unsigned long end,
> -			      unsigned migratetype, gfp_t gfp_mask);
> +			      acr_flags_t alloc_flags, gfp_t gfp_mask);
>  #define alloc_contig_range(...)			alloc_hooks(alloc_contig_range_noprof(__VA_ARGS__))
>  
>  extern struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
> diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
> index 7a681a49e73c..b61bca909ddc 100644
> --- a/include/linux/page-isolation.h
> +++ b/include/linux/page-isolation.h
> @@ -38,8 +38,19 @@ static inline void set_pageblock_isolate(struct page *page)
>  }
>  #endif
>  
> -#define MEMORY_OFFLINE	0x1
> -#define REPORT_FAILURE	0x2
> +/*
> + * Pageblock isolation modes:
> + * MEMORY_OFFLINE      - isolate to offline (!allocate) memory e.g., skip over
> + *		         PageHWPoison() pages and PageOffline() pages.
> + *		         Unmovable pages will be reported in this mode.
> + * CMA_ALLOCATION      - isolate for CMA allocations
> + * ISOLATE_MODE_OTHERS - isolate for other purposes
> + */
> +enum pb_isolate_mode {
> +	MEMORY_OFFLINE,
> +	CMA_ALLOCATION,
> +	ISOLATE_MODE_OTHERS,

Since this is in a .h file, I'd prefer more consistent naming, and longer
names shouldn't hurt as there are not that many users.

Even something like:
PB_ISOLATE_MODE_OFFLINE
PB_ISOLATE_MODE_CMA
PB_ISOLATE_MODE_OTHER

?
Re: [PATCH v5 6/6] mm/page_isolation: remove migratetype parameter from more functions.
Posted by Zi Yan 6 months, 3 weeks ago
On 27 May 2025, at 8:55, Vlastimil Babka wrote:

> On 5/23/25 21:12, Zi Yan wrote:
>> migratetype is no longer overwritten during pageblock isolation,
>> start_isolate_page_range(), has_unmovable_pages(), and
>> set_migratetype_isolate() no longer need which migratetype to restore
>> during isolation failure.
>>
>> For has_unmoable_pages(), it needs to know if the isolation is for CMA
>> allocation, so adding CMA_ALLOCATION to provide the information. At the
>> same time change isolation flags to enum pb_isolate_mode (MEMORY_OFFLINE,
>> CMA_ALLOCATION, and ISOLATE_MODE_OTHERS). Remove REPORT_FAILURE and check
>> MEMORY_OFFLINE instead, since only MEMORY_OFFLINE reports isolation
>> failures.
>>
>> alloc_contig_range() no longer needs migratetype. Replace it with
>> a newly defined acr_flags_t to tell if an allocation is for CMA. So does
>> __alloc_contig_migrate_range().
>>
>> Signed-off-by: Zi Yan <ziy@nvidia.com>
>> ---
>>  drivers/virtio/virtio_mem.c    |  3 +-
>>  include/linux/gfp.h            |  6 ++-
>>  include/linux/page-isolation.h | 19 ++++++++--
>>  include/trace/events/kmem.h    | 14 ++++---
>>  mm/cma.c                       |  2 +-
>>  mm/memory_hotplug.c            |  4 +-
>>  mm/page_alloc.c                | 25 ++++++-------
>>  mm/page_isolation.c            | 67 +++++++++++++++-------------------
>>  8 files changed, 72 insertions(+), 68 deletions(-)
>>
>> diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
>> index 56d0dbe62163..8accc0f255a8 100644
>> --- a/drivers/virtio/virtio_mem.c
>> +++ b/drivers/virtio/virtio_mem.c
>> @@ -1243,8 +1243,7 @@ static int virtio_mem_fake_offline(struct virtio_mem *vm, unsigned long pfn,
>>  		if (atomic_read(&vm->config_changed))
>>  			return -EAGAIN;
>>
>> -		rc = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE,
>> -					GFP_KERNEL);
>> +		rc = alloc_contig_range(pfn, pfn + nr_pages, 0, GFP_KERNEL);
>>  		if (rc == -ENOMEM)
>>  			/* whoops, out of memory */
>>  			return rc;
>> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
>> index be160e8d8bcb..dea27ed24f8e 100644
>> --- a/include/linux/gfp.h
>> +++ b/include/linux/gfp.h
>> @@ -423,9 +423,13 @@ static inline bool gfp_compaction_allowed(gfp_t gfp_mask)
>>  extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
>>
>>  #ifdef CONFIG_CONTIG_ALLOC
>> +
>> +typedef unsigned int __bitwise acr_flags_t;
>> +#define ACR_CMA		((__force acr_flags_t)BIT(0))	// allocate for CMA
>
> Would it make sense to define ACR_NONE as 0 so it's more descriptive than
> seeing 0 somewhere?

Totally. Will add one.

>
>> +
>>  /* The below functions must be run on a range from a single zone. */
>>  extern int alloc_contig_range_noprof(unsigned long start, unsigned long end,
>> -			      unsigned migratetype, gfp_t gfp_mask);
>> +			      acr_flags_t alloc_flags, gfp_t gfp_mask);
>>  #define alloc_contig_range(...)			alloc_hooks(alloc_contig_range_noprof(__VA_ARGS__))
>>
>>  extern struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
>> diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
>> index 7a681a49e73c..b61bca909ddc 100644
>> --- a/include/linux/page-isolation.h
>> +++ b/include/linux/page-isolation.h
>> @@ -38,8 +38,19 @@ static inline void set_pageblock_isolate(struct page *page)
>>  }
>>  #endif
>>
>> -#define MEMORY_OFFLINE	0x1
>> -#define REPORT_FAILURE	0x2
>> +/*
>> + * Pageblock isolation modes:
>> + * MEMORY_OFFLINE      - isolate to offline (!allocate) memory e.g., skip over
>> + *		         PageHWPoison() pages and PageOffline() pages.
>> + *		         Unmovable pages will be reported in this mode.
>> + * CMA_ALLOCATION      - isolate for CMA allocations
>> + * ISOLATE_MODE_OTHERS - isolate for other purposes
>> + */
>> +enum pb_isolate_mode {
>> +	MEMORY_OFFLINE,
>> +	CMA_ALLOCATION,
>> +	ISOLATE_MODE_OTHERS,
>
> Since this is in a .h file, I'd prefer more consistent naming, and longer
> names shouldn't hurt as there are not that many users.
>
> Even something like:
> PB_ISOLATE_MODE_OFFLINE
> PB_ISOLATE_MODE_CMA
> PB_ISOLATE_MODE_OTHER
>
> ?

OK. I am going to use more descriptive names below:

PB_ISOLATE_MODE_MEM_OFFLINE
PB_ISOLATE_MODE_CMA_ALLOC
PB_ISOLATE_MODE_OTHER

Thank you for all the suggestions and reviews. :)


Best Regards,
Yan, Zi
Re: [PATCH v5 6/6] mm/page_isolation: remove migratetype parameter from more functions.
Posted by Zi Yan 6 months, 3 weeks ago
On 23 May 2025, at 15:12, Zi Yan wrote:

> migratetype is no longer overwritten during pageblock isolation,
> start_isolate_page_range(), has_unmovable_pages(), and
> set_migratetype_isolate() no longer need which migratetype to restore
> during isolation failure.
>
> For has_unmoable_pages(), it needs to know if the isolation is for CMA
> allocation, so adding CMA_ALLOCATION to provide the information. At the
> same time change isolation flags to enum pb_isolate_mode (MEMORY_OFFLINE,
> CMA_ALLOCATION, and ISOLATE_MODE_OTHERS). Remove REPORT_FAILURE and check
> MEMORY_OFFLINE instead, since only MEMORY_OFFLINE reports isolation
> failures.
>
> alloc_contig_range() no longer needs migratetype. Replace it with
> a newly defined acr_flags_t to tell if an allocation is for CMA. So does
> __alloc_contig_migrate_range().
>
> Signed-off-by: Zi Yan <ziy@nvidia.com>
> ---
>  drivers/virtio/virtio_mem.c    |  3 +-
>  include/linux/gfp.h            |  6 ++-
>  include/linux/page-isolation.h | 19 ++++++++--
>  include/trace/events/kmem.h    | 14 ++++---
>  mm/cma.c                       |  2 +-
>  mm/memory_hotplug.c            |  4 +-
>  mm/page_alloc.c                | 25 ++++++-------
>  mm/page_isolation.c            | 67 +++++++++++++++-------------------
>  8 files changed, 72 insertions(+), 68 deletions(-)

This fixes mode's wrong type.

From 0c9792cd7ad1d1cd16b276b70d972e5b871ff653 Mon Sep 17 00:00:00 2001
From: Zi Yan <ziy@nvidia.com>
Date: Sun, 25 May 2025 21:29:06 -0400
Subject: [PATCH] fix mode's type.

Signed-off-by: Zi Yan <ziy@nvidia.com>
---
 mm/page_alloc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 48f458f7143a..3096304d1b58 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6901,8 +6901,8 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
 	};
 	INIT_LIST_HEAD(&cc.migratepages);
 	bool is_range_aligned;
-	isolate_mode_t mode = (alloc_flags & ACR_CMA) ? CMA_ALLOCATION :
-							ISOLATE_MODE_OTHERS;
+	enum pb_isolate_mode mode =
+		(alloc_flags & ACR_CMA) ? CMA_ALLOCATION : ISOLATE_MODE_OTHERS;

 	gfp_mask = current_gfp_context(gfp_mask);
 	if (__alloc_contig_verify_gfp_mask(gfp_mask, (gfp_t *)&cc.gfp_mask))
-- 
2.47.2



--
Best Regards,
Yan, Zi