On 7/14/26 15:09, Vlastimil Babka (SUSE) wrote: > On 7/14/26 15:05, David Hildenbrand (Arm) wrote: >> On 7/14/26 03:51, Ye Liu wrote: >>> 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. >>> >>> Signed-off-by: Ye Liu <[email protected]> >>> Reviewed-by: Zi Yan <[email protected]> >>> Reviewed-by: Vlastimil Babka (SUSE) <[email protected]> >>> --- >>> include/linux/migrate_mode.h | 1 + >>> include/trace/events/migrate.h | 3 ++- >>> mm/page_owner.c | 8 ++++---- >>> scripts/gdb/linux/page_owner.py | 4 +++- >>> 4 files changed, 10 insertions(+), 6 deletions(-) >>> >>> diff --git a/include/linux/migrate_mode.h b/include/linux/migrate_mode.h >>> index 265c4328b36a..05102d4d2490 100644 >>> --- a/include/linux/migrate_mode.h >>> +++ b/include/linux/migrate_mode.h >>> @@ -25,6 +25,7 @@ enum migrate_reason { >>> MR_LONGTERM_PIN, >>> MR_DEMOTION, >>> MR_DAMON, >>> + MR_NEVER, /* page has never been migrated */ >> >> Shouldn't this be more like >> >> "MR_NONE" ? >> >> As "never" is not really a "reason" ? > > It's not used ever as a reason that would be actually passed to migration.
Right, it's a placeholder for "there is no migrate reason because it is unset" > So I think the name is more descriptive this way. Not sure I agree. The usual translation of -1 -> unset is NONE or UNSET. At least I was confused by "NEVER". -- Cheers, David
