free_compound_page() is the only remaining dynamic destructor.
Call it unconditionally from destroy_large_folio() and convert it
to take a folio. It used to be the last thing called from
free_transhuge_folio(), and the call from destroy_large_folio()
will take care of that case too.
This was the last entry in the compound_page_dtors array, so delete it
and reword the comments that referred to it.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/mm.h | 11 +----------
mm/huge_memory.c | 1 -
mm/page_alloc.c | 23 +++++++----------------
3 files changed, 8 insertions(+), 27 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7fb529dbff31..cf6707a7069e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1267,14 +1267,7 @@ void folio_copy(struct folio *dst, struct folio *src);
unsigned long nr_free_buffer_pages(void);
-/*
- * Compound pages have a destructor function. Provide a
- * prototype for that function and accessor functions.
- * These are _only_ valid on the head of a compound page.
- */
-typedef void compound_page_dtor(struct page *);
-
-/* Keep the enum in sync with compound_page_dtors array in mm/page_alloc.c */
+/* Compound pages may have a special destructor */
enum compound_dtor_id {
NULL_COMPOUND_DTOR,
COMPOUND_PAGE_DTOR,
@@ -1325,8 +1318,6 @@ static inline unsigned long thp_size(struct page *page)
return PAGE_SIZE << thp_order(page);
}
-void free_compound_page(struct page *page);
-
#ifdef CONFIG_MMU
/*
* Do pte_mkwrite, but only if the vma says VM_WRITE. We do this when
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 516fe3c26ef3..99e36ad540c4 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2797,7 +2797,6 @@ void free_transhuge_folio(struct folio *folio)
}
spin_unlock_irqrestore(&ds_queue->split_queue_lock, flags);
}
- free_compound_page(&folio->page);
}
void deferred_split_folio(struct folio *folio)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index feb2e95cf021..804982faba4e 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -284,11 +284,6 @@ const char * const migratetype_names[MIGRATE_TYPES] = {
#endif
};
-static compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
- [NULL_COMPOUND_DTOR] = NULL,
- [COMPOUND_PAGE_DTOR] = free_compound_page,
-};
-
int min_free_kbytes = 1024;
int user_min_free_kbytes = -1;
static int watermark_boost_factor __read_mostly = 15000;
@@ -587,17 +582,17 @@ static inline void free_the_page(struct page *page, unsigned int order)
* The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded
* in bit 0 of page->compound_head. The rest of bits is pointer to head page.
*
- * The first tail page's ->compound_dtor holds the offset in array of compound
- * page destructors. See compound_page_dtors.
+ * The first tail page's ->compound_dtor describes how to destroy the
+ * compound page.
*
* The first tail page's ->compound_order holds the order of allocation.
* This usage means that zero-order pages may not be compound.
*/
-void free_compound_page(struct page *page)
+static void free_compound_page(struct folio *folio)
{
- mem_cgroup_uncharge(page_folio(page));
- free_the_page(page, compound_order(page));
+ mem_cgroup_uncharge(folio);
+ free_the_page(&folio->page, folio_order(folio));
}
void prep_compound_page(struct page *page, unsigned int order)
@@ -621,13 +616,9 @@ void destroy_large_folio(struct folio *folio)
return;
}
- if (folio_test_transhuge(folio) && dtor == TRANSHUGE_PAGE_DTOR) {
+ if (folio_test_transhuge(folio) && dtor == TRANSHUGE_PAGE_DTOR)
free_transhuge_folio(folio);
- return;
- }
-
- VM_BUG_ON_FOLIO(dtor >= NR_COMPOUND_DTORS, folio);
- compound_page_dtors[dtor](&folio->page);
+ free_compound_page(folio);
}
static inline void set_buddy_order(struct page *page, unsigned int order)
--
2.40.1
