From: Andrew Morton <akpm@linux-foundation.org>
To: mm-commits@vger.kernel.org,ye.liu@linux.dev,akpm@linux-foundation.org
Subject: + mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters.patch added to mm-unstable branch
Date: Wed, 01 Jul 2026 17:11:39 -0700 [thread overview]
Message-ID: <20260702001140.0CB8A1F000E9@smtp.kernel.org> (raw)
The patch titled
Subject: mm: use enum migrate_reason instead of int for migration reason parameters
has been added to the -mm mm-unstable branch. Its filename is
mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Ye Liu <ye.liu@linux.dev>
Subject: mm: use enum migrate_reason instead of int for migration reason parameters
Date: Wed, 1 Jul 2026 14:10:46 +0800
Replace all 'int reason' function parameters that carry migrate_reason
values with the proper 'enum migrate_reason' type. This makes the intent
explicit and leverages compiler type checking. The affected subsystems
are:
- page_owner: __folio_set_owner_migrate_reason(),
folio_set_owner_migrate_reason()
- migrate: migrate_pages(), migrate_pages_sync(),
migrate_pages_batch(), migrate_folios_move(),
migrate_hugetlbs(), unmap_and_move_huge_page()
- hugetlb: move_hugetlb_state(), htlb_allow_alloc_fallback()
- trace: mm_migrate_pages and mm_migrate_pages_start events
The 'short last_migrate_reason' struct field and internal helper
parameter in page_owner are intentionally left as 'short' since they
store per-page metadata where size matters.
No functional change.
Link: https://lore.kernel.org/20260701061101.344679-4-ye.liu@linux.dev
Signed-off-by: Ye Liu <ye.liu@linux.dev>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/hugetlb.h | 9 +++++----
include/linux/migrate.h | 6 ++++--
include/linux/page_owner.h | 7 ++++---
include/trace/events/migrate.h | 8 ++++----
mm/hugetlb.c | 3 ++-
mm/migrate.c | 12 ++++++------
mm/page_owner.c | 2 +-
7 files changed, 26 insertions(+), 21 deletions(-)
--- a/include/linux/hugetlb.h~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/include/linux/hugetlb.h
@@ -154,7 +154,8 @@ long hugetlb_unreserve_pages(struct inod
bool folio_isolate_hugetlb(struct folio *folio, struct list_head *list);
int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison);
void folio_putback_hugetlb(struct folio *folio);
-void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason);
+void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio,
+ enum migrate_reason reason);
void hugetlb_fix_reserve_counts(struct inode *inode);
extern struct mutex *hugetlb_fault_mutex_table;
u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx);
@@ -424,7 +425,7 @@ static inline void folio_putback_hugetlb
}
static inline void move_hugetlb_state(struct folio *old_folio,
- struct folio *new_folio, int reason)
+ struct folio *new_folio, enum migrate_reason reason)
{
}
@@ -956,7 +957,7 @@ static inline gfp_t htlb_modify_alloc_ma
return modified_mask;
}
-static inline bool htlb_allow_alloc_fallback(int reason)
+static inline bool htlb_allow_alloc_fallback(enum migrate_reason reason)
{
bool allowed_fallback = false;
@@ -1238,7 +1239,7 @@ static inline gfp_t htlb_modify_alloc_ma
return 0;
}
-static inline bool htlb_allow_alloc_fallback(int reason)
+static inline bool htlb_allow_alloc_fallback(enum migrate_reason reason)
{
return false;
}
--- a/include/linux/migrate.h~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/include/linux/migrate.h
@@ -57,7 +57,8 @@ void putback_movable_pages(struct list_h
int migrate_folio(struct address_space *mapping, struct folio *dst,
struct folio *src, enum migrate_mode mode);
int migrate_pages(struct list_head *l, new_folio_t new, free_folio_t free,
- unsigned long private, enum migrate_mode mode, int reason,
+ unsigned long private, enum migrate_mode mode,
+ enum migrate_reason reason,
unsigned int *ret_succeeded);
struct folio *alloc_migration_target(struct folio *src, unsigned long private);
bool isolate_movable_ops_page(struct page *page, isolate_mode_t mode);
@@ -77,7 +78,8 @@ int set_movable_ops(const struct movable
static inline void putback_movable_pages(struct list_head *l) {}
static inline int migrate_pages(struct list_head *l, new_folio_t new,
free_folio_t free, unsigned long private,
- enum migrate_mode mode, int reason, unsigned int *ret_succeeded)
+ enum migrate_mode mode, enum migrate_reason reason,
+ unsigned int *ret_succeeded)
{ return -ENOSYS; }
static inline struct folio *alloc_migration_target(struct folio *src,
unsigned long private)
--- a/include/linux/page_owner.h~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/include/linux/page_owner.h
@@ -3,6 +3,7 @@
#define __LINUX_PAGE_OWNER_H
#include <linux/jump_label.h>
+#include <linux/migrate_mode.h>
#ifdef CONFIG_PAGE_OWNER
extern struct static_key_false page_owner_inited;
@@ -14,7 +15,7 @@ extern void __set_page_owner(struct page
extern void __split_page_owner(struct page *page, int old_order,
int new_order);
extern void __folio_copy_owner(struct folio *newfolio, struct folio *old);
-extern void __folio_set_owner_migrate_reason(struct folio *folio, int reason);
+extern void __folio_set_owner_migrate_reason(struct folio *folio, enum migrate_reason reason);
extern void __dump_page_owner(const struct page *page);
extern void pagetypeinfo_showmixedcount_print(struct seq_file *m,
pg_data_t *pgdat, struct zone *zone);
@@ -43,7 +44,7 @@ static inline void folio_copy_owner(stru
if (static_branch_unlikely(&page_owner_inited))
__folio_copy_owner(newfolio, old);
}
-static inline void folio_set_owner_migrate_reason(struct folio *folio, int reason)
+static inline void folio_set_owner_migrate_reason(struct folio *folio, enum migrate_reason reason)
{
if (static_branch_unlikely(&page_owner_inited))
__folio_set_owner_migrate_reason(folio, reason);
@@ -68,7 +69,7 @@ static inline void split_page_owner(stru
static inline void folio_copy_owner(struct folio *newfolio, struct folio *folio)
{
}
-static inline void folio_set_owner_migrate_reason(struct folio *folio, int reason)
+static inline void folio_set_owner_migrate_reason(struct folio *folio, enum migrate_reason reason)
{
}
static inline void dump_page_owner(const struct page *page)
--- a/include/trace/events/migrate.h~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/include/trace/events/migrate.h
@@ -52,7 +52,7 @@ TRACE_EVENT(mm_migrate_pages,
TP_PROTO(unsigned long succeeded, unsigned long failed,
unsigned long thp_succeeded, unsigned long thp_failed,
unsigned long thp_split, unsigned long large_folio_split,
- enum migrate_mode mode, int reason),
+ enum migrate_mode mode, enum migrate_reason reason),
TP_ARGS(succeeded, failed, thp_succeeded, thp_failed,
thp_split, large_folio_split, mode, reason),
@@ -65,7 +65,7 @@ TRACE_EVENT(mm_migrate_pages,
__field( unsigned long, thp_split)
__field( unsigned long, large_folio_split)
__field( enum migrate_mode, mode)
- __field( int, reason)
+ __field( enum migrate_reason, reason)
),
TP_fast_assign(
@@ -92,13 +92,13 @@ TRACE_EVENT(mm_migrate_pages,
TRACE_EVENT(mm_migrate_pages_start,
- TP_PROTO(enum migrate_mode mode, int reason),
+ TP_PROTO(enum migrate_mode mode, enum migrate_reason reason),
TP_ARGS(mode, reason),
TP_STRUCT__entry(
__field(enum migrate_mode, mode)
- __field(int, reason)
+ __field(enum migrate_reason, reason)
),
TP_fast_assign(
--- a/mm/hugetlb.c~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/mm/hugetlb.c
@@ -7182,7 +7182,8 @@ void folio_putback_hugetlb(struct folio
folio_put(folio);
}
-void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason)
+void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio,
+ enum migrate_reason reason)
{
struct hstate *h = folio_hstate(old_folio);
--- a/mm/migrate.c~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/mm/migrate.c
@@ -1469,7 +1469,7 @@ out:
static int unmap_and_move_huge_page(new_folio_t get_new_folio,
free_folio_t put_new_folio, unsigned long private,
struct folio *src, int force, enum migrate_mode mode,
- int reason, struct list_head *ret)
+ enum migrate_reason reason, struct list_head *ret)
{
struct folio *dst;
int rc = -EAGAIN;
@@ -1626,7 +1626,7 @@ struct migrate_pages_stats {
*/
static int migrate_hugetlbs(struct list_head *from, new_folio_t get_new_folio,
free_folio_t put_new_folio, unsigned long private,
- enum migrate_mode mode, int reason,
+ enum migrate_mode mode, enum migrate_reason reason,
struct migrate_pages_stats *stats,
struct list_head *ret_folios)
{
@@ -1716,7 +1716,7 @@ static int migrate_hugetlbs(struct list_
static void migrate_folios_move(struct list_head *src_folios,
struct list_head *dst_folios,
free_folio_t put_new_folio, unsigned long private,
- enum migrate_mode mode, int reason,
+ enum migrate_mode mode, enum migrate_reason reason,
struct list_head *ret_folios,
struct migrate_pages_stats *stats,
int *retry, int *thp_retry, int *nr_failed,
@@ -1799,7 +1799,7 @@ static void migrate_folios_undo(struct l
*/
static int migrate_pages_batch(struct list_head *from,
new_folio_t get_new_folio, free_folio_t put_new_folio,
- unsigned long private, enum migrate_mode mode, int reason,
+ unsigned long private, enum migrate_mode mode, enum migrate_reason reason,
struct list_head *ret_folios, struct list_head *split_folios,
struct migrate_pages_stats *stats, int nr_pass)
{
@@ -2011,7 +2011,7 @@ out:
static int migrate_pages_sync(struct list_head *from, new_folio_t get_new_folio,
free_folio_t put_new_folio, unsigned long private,
- enum migrate_mode mode, int reason,
+ enum migrate_mode mode, enum migrate_reason reason,
struct list_head *ret_folios, struct list_head *split_folios,
struct migrate_pages_stats *stats)
{
@@ -2088,7 +2088,7 @@ static int migrate_pages_sync(struct lis
*/
int migrate_pages(struct list_head *from, new_folio_t get_new_folio,
free_folio_t put_new_folio, unsigned long private,
- enum migrate_mode mode, int reason, unsigned int *ret_succeeded)
+ enum migrate_mode mode, enum migrate_reason reason, unsigned int *ret_succeeded)
{
int rc, rc_gather;
int nr_pages;
--- a/mm/page_owner.c~mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters
+++ a/mm/page_owner.c
@@ -345,7 +345,7 @@ noinline void __set_page_owner(struct pa
inc_stack_record_count(handle, gfp_mask, 1 << order);
}
-void __folio_set_owner_migrate_reason(struct folio *folio, int reason)
+void __folio_set_owner_migrate_reason(struct folio *folio, enum migrate_reason reason)
{
struct page_ext *page_ext = page_ext_get(&folio->page);
struct page_owner *page_owner;
_
Patches currently in -mm which might be from ye.liu@linux.dev are
mm-page_owner-extract-skip_buddy_pages-helper-to-unify-buddy-page-skipping.patch
mm-page_owner-add-mr_never-to-enum-migrate_reason-and-use-it-for-last_migrate_reason.patch
mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters.patch
mm-page_owner-hoist-config_memcg-to-function-level-for-print_page_owner_memcg.patch
mm-page_owner-add-missing-newline-to-count_threshold-format-string.patch
mm-page_owner-move-free_ts_nsec-output-to-free-section-in-__dump_page_owner.patch
mm-page_owner-drop-redundant-page_owner-prefix-from-static-symbols.patch
mm-page_owner-clamp-skip_buddy_pages-pfn-advance-at-max_order_nr_pages-boundary.patch
mm-page_owner-use-memcg_data-snapshot-instead-of-pagememcgkmem-to-avoid-toctou-vm_bug_on.patch
next reply other threads:[~2026-07-02 0:11 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-02 0:11 Andrew Morton [this message]
-- strict thread matches above, loose matches on Subject: below --
2026-07-01 3:41 + mm-use-enum-migrate_reason-instead-of-int-for-migration-reason-parameters.patch added to mm-unstable branch Andrew Morton
2026-06-30 2:29 Andrew Morton
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