Commit 0386aaa6 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

bootmem: stop using page->index 

Encode the type into the bottom four bits of page->private and the info
into the remaining bits.  Also turn the bootmem type into a named enum.

[arnd@arndb.de: bootmem: add bootmem_type stub function]
  Link: https://lkml.kernel.org/r/20241015143802.577613-1-arnd@kernel.org
[akpm@linux-foundation.org: fix build with !CONFIG_HAVE_BOOTMEM_INFO_NODE]
 Link: https://lore.kernel.org/oe-kbuild-all/202410090311.eaqcL7IZ-lkp@intel.com/
Link: https://lkml.kernel.org/r/20241005200121.3231142-6-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 68158bfa

arch/x86/mm/init_64.c

+19 −9
Original line number Diff line number Diff line
@@ -985,23 +985,33 @@ int arch_add_memory(int nid, u64 start, u64 size, 
	return add_pages(nid, start_pfn, nr_pages, params);

}



static void __meminit free_pagetable(struct page *page, int order)

static void free_reserved_pages(struct page *page, unsigned long nr_pages)

{

	unsigned long magic;

	unsigned int nr_pages = 1 << order;

	while (nr_pages--)

		free_reserved_page(page++);

}



static void __meminit free_pagetable(struct page *page, int order)

{

	/* bootmem page has reserved flag */

	if (PageReserved(page)) {

		magic = page->index;

		if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {

		unsigned long nr_pages = 1 << order;

#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE

		enum bootmem_type type = bootmem_type(page);



		if (type == SECTION_INFO || type == MIX_SECTION_INFO) {

			while (nr_pages--)

				put_page_bootmem(page++);

		} else

			while (nr_pages--)

				free_reserved_page(page++);

	} else

		} else {

			free_reserved_pages(page, nr_pages);

		}

#else

		free_reserved_pages(page, nr_pages);

#endif

	} else {

		free_pages((unsigned long)page_address(page), order);

	}

}



static void __meminit free_hugepage_table(struct page *page,

		struct vmem_altmap *altmap)

include/linux/bootmem_info.h

+27 −8
Original line number Diff line number Diff line
@@ -6,11 +6,10 @@ 
#include <linux/kmemleak.h>



/*

 * Types for free bootmem stored in page->lru.next. These have to be in

 * some random range in unsigned long space for debugging purposes.

 * Types for free bootmem stored in the low bits of page->private.

 */

enum {

	MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 12,

enum bootmem_type {

	MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 1,

	SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,

	MIX_SECTION_INFO,

	NODE_INFO,
@@ -21,9 +20,19 @@ enum { 
void __init register_page_bootmem_info_node(struct pglist_data *pgdat);



void get_page_bootmem(unsigned long info, struct page *page,

		      unsigned long type);

		enum bootmem_type type);

void put_page_bootmem(struct page *page);



static inline enum bootmem_type bootmem_type(const struct page *page)

{

	return (unsigned long)page->private & 0xf;

}



static inline unsigned long bootmem_info(const struct page *page)

{

	return (unsigned long)page->private >> 4;

}



/*

 * Any memory allocated via the memblock allocator and not via the

 * buddy will be marked reserved already in the memmap. For those
@@ -31,7 +40,7 @@ void put_page_bootmem(struct page *page); 
 */

static inline void free_bootmem_page(struct page *page)

{

	unsigned long magic = page->index;

	enum bootmem_type type = bootmem_type(page);



	/*

	 * The reserve_bootmem_region sets the reserved flag on bootmem
@@ -39,7 +48,7 @@ static inline void free_bootmem_page(struct page *page) 
	 */

	VM_BUG_ON_PAGE(page_ref_count(page) != 2, page);



	if (magic == SECTION_INFO || magic == MIX_SECTION_INFO)

	if (type == SECTION_INFO || type == MIX_SECTION_INFO)

		put_page_bootmem(page);

	else

		VM_BUG_ON_PAGE(1, page);
@@ -53,8 +62,18 @@ static inline void put_page_bootmem(struct page *page) 
{

}



static inline enum bootmem_type bootmem_type(const struct page *page)

{

	return SECTION_INFO;

}



static inline unsigned long bootmem_info(const struct page *page)

{

	return 0;

}



static inline void get_page_bootmem(unsigned long info, struct page *page,

				    unsigned long type)

				    enum bootmem_type type)

{

}

mm/bootmem_info.c

+6 −5
Original line number Diff line number Diff line
@@ -14,23 +14,24 @@ 
#include <linux/memory_hotplug.h>

#include <linux/kmemleak.h>



void get_page_bootmem(unsigned long info, struct page *page, unsigned long type)

void get_page_bootmem(unsigned long info, struct page *page,

		enum bootmem_type type)

{

	page->index = type;

	BUG_ON(type > 0xf);

	BUG_ON(info > (ULONG_MAX >> 4));

	SetPagePrivate(page);

	set_page_private(page, info);

	set_page_private(page, info << 4 | type);

	page_ref_inc(page);

}



void put_page_bootmem(struct page *page)

{

	unsigned long type = page->index;

	enum bootmem_type type = bootmem_type(page);



	BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE ||

	       type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE);



	if (page_ref_dec_return(page) == 1) {

		page->index = 0;

		ClearPagePrivate(page);

		set_page_private(page, 0);

		INIT_LIST_HEAD(&page->lru);

mm/sparse.c

+4 −4
Original line number Diff line number Diff line
@@ -720,19 +720,19 @@ static void depopulate_section_memmap(unsigned long pfn, unsigned long nr_pages, 
static void free_map_bootmem(struct page *memmap)

{

	unsigned long maps_section_nr, removing_section_nr, i;

	unsigned long magic, nr_pages;

	unsigned long type, nr_pages;

	struct page *page = virt_to_page(memmap);



	nr_pages = PAGE_ALIGN(PAGES_PER_SECTION * sizeof(struct page))

		>> PAGE_SHIFT;



	for (i = 0; i < nr_pages; i++, page++) {

		magic = page->index;

		type = bootmem_type(page);



		BUG_ON(magic == NODE_INFO);

		BUG_ON(type == NODE_INFO);



		maps_section_nr = pfn_to_section_nr(page_to_pfn(page));

		removing_section_nr = page_private(page);

		removing_section_nr = bootmem_info(page);



		/*

		 * When this function is called, the removing section is