[RFC PATCH 4/4] mm/page_isolation: remove migratetype parameter from more functions.

From: Zi Yan
Date: Wed Aug 28 2024 - 16:24:15 EST


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 isolation
flags to provide the information.

Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
include/linux/page-isolation.h | 3 ++-
mm/memory_hotplug.c | 1 -
mm/page_alloc.c | 4 +++-
mm/page_isolation.c | 27 +++++++++++----------------
4 files changed, 16 insertions(+), 19 deletions(-)

diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index c2a1bd621561..e94117101b6c 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -32,13 +32,14 @@ static inline bool is_migrate_isolate(int migratetype)

#define MEMORY_OFFLINE 0x1
#define REPORT_FAILURE 0x2
+#define CMA_ALLOCATION 0x4

void set_pageblock_migratetype(struct page *page, int migratetype);

bool move_freepages_block_isolate(struct zone *zone, struct page *page);

int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
- int migratetype, int flags, gfp_t gfp_flags);
+ int flags, gfp_t gfp_flags);

void undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn);

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 4265272faf4c..fe0b71e0f307 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1993,7 +1993,6 @@ int offline_pages(unsigned long start_pfn, unsigned long nr_pages,

/* set above range as isolated */
ret = start_isolate_page_range(start_pfn, end_pfn,
- MIGRATE_MOVABLE,
MEMORY_OFFLINE | REPORT_FAILURE,
GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL);
if (ret) {
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4d06932ba69a..c60bb95d7e65 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6607,7 +6607,9 @@ 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, gfp_mask);
+ ret = start_isolate_page_range(start, end,
+ migratetype == MIGRATE_CMA ? CMA_ALLOCATION : 0,
+ gfp_mask);
if (ret)
goto done;

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 4c65157d78ef..07c58b82db76 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)
+ int flags)
{
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 (flags & CMA_ALLOCATION)
return NULL;

return page;
@@ -144,7 +144,7 @@ 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, int isol_flags,
unsigned long start_pfn, unsigned long end_pfn)
{
struct zone *zone = page_zone(page);
@@ -179,7 +179,7 @@ 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);
+ isol_flags);
if (!unmovable) {
if (!move_freepages_block_isolate(zone, page)) {
spin_unlock_irqrestore(&zone->lock, flags);
@@ -290,7 +290,6 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
* @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
@@ -306,8 +305,7 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
* the in-use page then splitting the free page.
*/
static int isolate_single_pageblock(unsigned long boundary_pfn, int flags,
- gfp_t gfp_flags, bool isolate_before, bool skip_isolation,
- int migratetype)
+ gfp_t gfp_flags, bool isolate_before, bool skip_isolation)
{
unsigned long start_pfn;
unsigned long isolate_pageblock;
@@ -333,11 +331,9 @@ 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,
+ ret = set_migratetype_isolate(pfn_to_page(isolate_pageblock),
flags, isolate_pageblock, isolate_pageblock + pageblock_nr_pages);

if (ret)
@@ -436,7 +432,6 @@ 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
@@ -478,7 +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, gfp_t gfp_flags)
+ int flags, gfp_t gfp_flags)
{
unsigned long pfn;
struct page *page;
@@ -490,7 +485,7 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,

/* isolate [isolate_start, isolate_start + pageblock_nr_pages) pageblock */
ret = isolate_single_pageblock(isolate_start, flags, gfp_flags, false,
- skip_isolation, migratetype);
+ skip_isolation);
if (ret)
return ret;

@@ -499,7 +494,7 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,

/* isolate [isolate_end - pageblock_nr_pages, isolate_end) pageblock */
ret = isolate_single_pageblock(isolate_end, flags, gfp_flags, true,
- skip_isolation, migratetype);
+ skip_isolation);
if (ret) {
unset_migratetype_isolate(pfn_to_page(isolate_start));
return ret;
@@ -510,7 +505,7 @@ 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,
+ if (page && set_migratetype_isolate(page, flags,
start_pfn, end_pfn)) {
undo_isolate_page_range(isolate_start, pfn);
unset_migratetype_isolate(
--
2.45.2