init_compound_tail() is only used by vmemmap_shared_tail_page(), where
the shared tail page setup intentionally passes NULL as the compound head.

Keeping this helper in mm/internal.h exposes that special case to the rest
of the MM code and can make the NULL head argument look generally valid.
Open-code the initialization at the only call site so the special-case use
stays local to sparse vmemmap optimization.

No functional change intended.

Signed-off-by: Muchun Song <[email protected]>
Acked-by: Qi Zheng <[email protected]>
Acked-by: David Hildenbrand (Arm) <[email protected]>
---
v3:
- Collect Acked-by from David Hildenbrand

v2:
- Collect Acked-by from Qi Zheng
---
 mm/internal.h       | 9 ---------
 mm/sparse-vmemmap.c | 5 ++++-
 2 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/mm/internal.h b/mm/internal.h
index da14c56fb24e..0dca33db068f 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -786,15 +786,6 @@ static inline void prep_compound_tail(struct page *tail,
        VM_WARN_ON_ONCE(tail->private);
 }
 
-static inline void init_compound_tail(struct page *tail,
-               const struct page *head, unsigned int order, struct zone *zone)
-{
-       atomic_set(&tail->_mapcount, -1);
-       set_page_node(tail, zone_to_nid(zone));
-       set_page_zone(tail, zone_idx(zone));
-       prep_compound_tail(tail, head, order);
-}
-
 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
 
 /*
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 7388a5b5cce3..861e09b2b096 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -189,7 +189,10 @@ struct page __ref *vmemmap_shared_tail_page(unsigned int 
order, struct zone *zon
        for (int i = 0; i < PAGE_SIZE / sizeof(struct page); i++) {
                page = (struct page *)addr + i;
                mm_zero_struct_page(page);
-               init_compound_tail(page, NULL, order, zone);
+               atomic_set(&page->_mapcount, -1);
+               set_page_node(page, zone_to_nid(zone));
+               set_page_zone(page, zone_idx(zone));
+               prep_compound_tail(page, NULL, order);
        }
 
        page = virt_to_page(addr);
-- 
2.54.0


Reply via email to