From 7eeed888c99a0619911165030bf3f82b265c141a Mon Sep 17 00:00:00 2001 From: Ye Liu Date: Tue, 14 Jul 2026 09:51:01 +0800 Subject: mm/page_owner: add MR_NEVER to enum migrate_reason and use it for last_migrate_reason The last_migrate_reason field uses -1 as a sentinel value to mean "no migration has happened". Replace the four bare -1 occurrences by adding a proper MR_NEVER member to enum migrate_reason, defining a corresponding "never_migrated" string in the MIGRATE_REASON trace macro, and updating the GDB page_owner script to use MR_NEVER instead of the hardcoded -1 so that lx-dump-page-owner does not incorrectly report unmigrated pages as migrated. No functional change. Link: https://lore.kernel.org/20260714015117.78351-3-ye.liu@linux.dev Signed-off-by: Ye Liu Reviewed-by: Zi Yan Reviewed-by: Vlastimil Babka (SUSE) Cc: Brendan Jackman Cc: Johannes Weiner Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Suren Baghdasaryan Cc: David Hildenbrand (Arm) Signed-off-by: Andrew Morton --- scripts/gdb/linux/page_owner.py | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/gdb/linux/page_owner.py b/scripts/gdb/linux/page_owner.py index 8e713a09cfe7..eeabaeed438b 100644 --- a/scripts/gdb/linux/page_owner.py +++ b/scripts/gdb/linux/page_owner.py @@ -34,6 +34,7 @@ class DumpPageOwner(gdb.Command): max_pfn = None p_ops = None migrate_reason_names = None + mr_never = None def __init__(self): super(DumpPageOwner, self).__init__("lx-dump-page-owner", gdb.COMMAND_SUPPORT) @@ -65,6 +66,7 @@ class DumpPageOwner(gdb.Command): self.max_pfn = int(gdb.parse_and_eval("max_pfn")) self.page_ext_size = int(gdb.parse_and_eval("page_ext_size")) self.migrate_reason_names = gdb.parse_and_eval('migrate_reason_names') + self.mr_never = int(gdb.parse_and_eval('MR_NEVER')) def page_ext_invalid(self, page_ext): if page_ext == gdb.Value(0): @@ -138,7 +140,7 @@ class DumpPageOwner(gdb.Command): else: gdb.write('page last free stack trace:\n') stackdepot.stack_depot_print(page_owner["free_handle"]) - if page_owner['last_migrate_reason'] != -1: + if page_owner['last_migrate_reason'] != self.mr_never: gdb.write('page has been migrated, last migrate reason: %s\n' % self.migrate_reason_names[page_owner['last_migrate_reason']]) def read_page_owner(self): -- cgit