[PATCH v2 0/6] mm/page_owner: misc cleanups

[Ye Liu <ye.liu@linux.dev>]

v2:
 - Add cover letter (no code changes).
 - Link:https://lore.kernel.org/all/20260623065234.31866-2-ye.liu@linux.dev/

This series collects a few cleanups for mm/page_owner.c that have been 
accumulated while reading through the file.  There is no functional    
change -- the goal is to make the code easier to read and maintain.    
                                                                       
Patch 1 consolidates three identical PageBuddy skip blocks into a      
single skip_buddy_pages() helper, eliminating the duplication and      
keeping the lockless-read comment in one place.                        
                                                                       
Patch 2 replaces the -1 magic number used for "never migrated" with    
a local MIGRATE_REASON_NONE define, making the intent explicit at      
every use site.                                                        
                                                                       
Patch 3 hoists the CONFIG_MEMCG guard out of print_page_owner_memcg()'s
body so that the real implementation and the empty stub are two clearly
separate definitions, the common kernel idiom.                         
                                                                       
Patch 4 adds a missing \n to the count_threshold debugfs attribute     
format string so that cat(1) output is properly terminated.            
                                                                       
Patch 5 moves free_ts_nsec from the allocation summary line to the     
free section in __dump_page_owner(), grouping it with free_pid and     
free_tgid where it logically belongs.  This also makes the dump        
output consistent with print_page_owner().                             
                                                                       
Patch 6 drops the redundant page_owner_ prefix from file-scoped static 
symbols (stack_fops, threshold_fops, etc.).  Since they cannot collide 
across translation units, the prefix carries no information.           
                                                                       
The series is based on v6.17-rc1 and has been compile-tested with and  
without CONFIG_MEMCG.                                                  

Ye Liu (6):
  mm/page_owner: extract skip_buddy_pages() helper to unify buddy page
    skipping
  mm/page_owner: use MIGRATE_REASON_NONE instead of -1 for
    last_migrate_reason
  mm/page_owner: hoist CONFIG_MEMCG to function level for
    print_page_owner_memcg()
  mm/page_owner: add missing newline to count_threshold format string
  mm/page_owner: move free_ts_nsec output to free section in
    __dump_page_owner()
  mm/page_owner: drop redundant page_owner prefix from static symbols

 mm/page_owner.c | 121 +++++++++++++++++++++++++++---------------------
 1 file changed, 67 insertions(+), 54 deletions(-)

-- 
2.43.0