[RFC v2 06/10] mm: rename init_page_count() -> page_ref_init()

From: Pasha Tatashin
Date: Tue Nov 16 2021 - 20:21:25 EST


Now, that set_page_count() is not called from outside anymore and about
to be removed, init_page_count() is the only function that is going to
be used to unconditionally set _refcount, however it is restricted to set
it only to 1.

Make init_page_count() aligned with the other page_ref_*
functions by renaming it.

Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
arch/m68k/mm/motorola.c | 2 +-
include/linux/mm.h | 2 +-
include/linux/page_ref.h | 10 +++++++---
mm/page_alloc.c | 2 +-
4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
index 2b05bb2bac00..e81ecafedff3 100644
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -133,7 +133,7 @@ void __init init_pointer_table(void *table, int type)

/* unreserve the page so it's possible to free that page */
__ClearPageReserved(PD_PAGE(dp));
- init_page_count(PD_PAGE(dp));
+ page_ref_init(PD_PAGE(dp));

return;
}
diff --git a/include/linux/mm.h b/include/linux/mm.h
index a7e4a9e7d807..736bf16e7104 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2506,7 +2506,7 @@ extern void reserve_bootmem_region(phys_addr_t start, phys_addr_t end);
static inline void free_reserved_page(struct page *page)
{
ClearPageReserved(page);
- init_page_count(page);
+ page_ref_init(page);
__free_page(page);
adjust_managed_page_count(page, 1);
}
diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index 27880aca2e2f..ff946d753df8 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -107,10 +107,14 @@ static inline void folio_set_count(struct folio *folio, int v)
}

/*
- * Setup the page count before being freed into the page allocator for
- * the first time (boot or memory hotplug)
+ * Setup the page refcount to one before being freed into the page allocator.
+ * The memory might not be initialized and therefore there cannot be any
+ * assumptions about the current value of page->_refcount. This call should be
+ * done during boot when memory is being initialized, during memory hotplug
+ * when new memory is added, or when a previous reserved memory is unreserved
+ * this is the first time kernel take control of the given memory.
*/
-static inline void init_page_count(struct page *page)
+static inline void page_ref_init(struct page *page)
{
set_page_count(page, 1);
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 217c0c9fa25b..fc828dfde4fc 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1555,7 +1555,7 @@ static void __meminit __init_single_page(struct page *page, unsigned long pfn,
{
mm_zero_struct_page(page);
set_page_links(page, zone, nid, pfn);
- init_page_count(page);
+ page_ref_init(page);
page_mapcount_reset(page);
page_cpupid_reset_last(page);
page_kasan_tag_reset(page);
--
2.34.0.rc1.387.gb447b232ab-goog