Small cleanup series for mm/vmalloc.c, no functional changes:

- Group xa_init() with the other vmap_block_queue field initializations
  in vmalloc_init(), instead of after the unrelated vfree_deferred setup.

- Extract vmap_insert_free_area() helper to deduplicate the allocate-
  and-insert pattern that appeared both inside the loop body and after
  the loop in vmap_init_free_space().

- Extract show_busy_info() from vmalloc_info_show(), mirroring the
  existing show_purge_info() pattern, so the top-level show function
  only orchestrates the two data sources.

Signed-off-by: Ye Liu <liuye@kylinos.cn>
---
Changes in v2:
- Patch2: Keep space after (unsigned long) cast per Uladzislau's review.
- Patch3: Drop the NULL initialization of counters in show_busy_info. 
- Link to v1: https://lore.kernel.org/r/20260914-vmalloc_study-v1-0-526f68559706@linux.dev

---
Ye Liu (3):
      mm/vmalloc: group xa_init with vbq field initializations
      mm/vmalloc: extract vmap_insert_free_area helper
      mm/vmalloc: extract show_busy_info from vmalloc_info_show

 mm/vmalloc.c | 56 +++++++++++++++++++++++++++++---------------------------
 1 file changed, 29 insertions(+), 27 deletions(-)
---
base-commit: 68142f986ff04b2b70b31db00f719bf690f64a9a
change-id: 20260914-vmalloc_study-b3fe7c738f2a

Best regards,
-- 
Ye Liu <ye.liu@linux.dev>