The patch titled
Subject: mm: rename page_order() to buddy_order()
has been added to the -mm tree. Its filename is
mm-rename-page_order-to-buddy_order.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-rename-page_order-to-buddy_order.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-rename-page_order-to-buddy_order.patch
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: rename page_order() to buddy_order()
The current page_order() can only be called on pages in the buddy
allocator. For compound pages, you have to use compound_order(). This is
confusing and led to a bug, so rename page_order() to buddy_order().
Link: https://lkml.kernel.org/r/20201001152259.14932-2-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/compaction.c | 6 +++---
mm/internal.h | 8 ++++----
mm/page_alloc.c | 30 +++++++++++++++---------------
mm/page_isolation.c | 4 ++--
mm/page_owner.c | 6 +++---
mm/page_reporting.c | 2 +-
mm/shuffle.c | 2 +-
7 files changed, 29 insertions(+), 29 deletions(-)
--- a/mm/compaction.c~mm-rename-page_order-to-buddy_order
+++ a/mm/compaction.c
@@ -625,7 +625,7 @@ static unsigned long isolate_freepages_b
}
/* Found a free page, will break it into order-0 pages */
- order = page_order(page);
+ order = buddy_order(page);
isolated = __isolate_free_page(page, order);
if (!isolated)
break;
@@ -898,7 +898,7 @@ isolate_migratepages_block(struct compac
* potential isolation targets.
*/
if (PageBuddy(page)) {
- unsigned long freepage_order = page_order_unsafe(page);
+ unsigned long freepage_order = buddy_order_unsafe(page);
/*
* Without lock, we cannot be sure that what we got is
@@ -1172,7 +1172,7 @@ static bool suitable_migration_target(st
* the only small danger is that we skip a potentially suitable
* pageblock, so it's not worth to check order for valid range.
*/
- if (page_order_unsafe(page) >= pageblock_order)
+ if (buddy_order_unsafe(page) >= pageblock_order)
return false;
}
--- a/mm/internal.h~mm-rename-page_order-to-buddy_order
+++ a/mm/internal.h
@@ -270,16 +270,16 @@ int find_suitable_fallback(struct free_a
* page from being allocated in parallel and returning garbage as the order.
* If a caller does not hold page_zone(page)->lock, it must guarantee that the
* page cannot be allocated or merged in parallel. Alternatively, it must
- * handle invalid values gracefully, and use page_order_unsafe() below.
+ * handle invalid values gracefully, and use buddy_order_unsafe() below.
*/
-static inline unsigned int page_order(struct page *page)
+static inline unsigned int buddy_order(struct page *page)
{
/* PageBuddy() must be checked by the caller */
return page_private(page);
}
/*
- * Like page_order(), but for callers who cannot afford to hold the zone lock.
+ * Like buddy_order(), but for callers who cannot afford to hold the zone lock.
* PageBuddy() should be checked first by the caller to minimize race window,
* and invalid values must be handled gracefully.
*
@@ -289,7 +289,7 @@ static inline unsigned int page_order(st
* times, potentially observing different values in the tests and the actual
* use of the result.
*/
-#define page_order_unsafe(page) READ_ONCE(page_private(page))
+#define buddy_order_unsafe(page) READ_ONCE(page_private(page))
static inline bool is_cow_mapping(vm_flags_t flags)
{
--- a/mm/page_alloc.c~mm-rename-page_order-to-buddy_order
+++ a/mm/page_alloc.c
@@ -763,7 +763,7 @@ static inline void clear_page_guard(stru
unsigned int order, int migratetype) {}
#endif
-static inline void set_page_order(struct page *page, unsigned int order)
+static inline void set_buddy_order(struct page *page, unsigned int order)
{
set_page_private(page, order);
__SetPageBuddy(page);
@@ -788,7 +788,7 @@ static inline bool page_is_buddy(struct
if (!page_is_guard(buddy) && !PageBuddy(buddy))
return false;
- if (page_order(buddy) != order)
+ if (buddy_order(buddy) != order)
return false;
/*
@@ -1026,7 +1026,7 @@ continue_merging:
}
done_merging:
- set_page_order(page, order);
+ set_buddy_order(page, order);
if (is_shuffle_order(order))
to_tail = shuffle_pick_tail();
@@ -2132,7 +2132,7 @@ static inline void expand(struct zone *z
continue;
add_to_free_list(&page[size], zone, high, migratetype);
- set_page_order(&page[size], high);
+ set_buddy_order(&page[size], high);
}
}
@@ -2346,7 +2346,7 @@ static int move_freepages(struct zone *z
VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
VM_BUG_ON_PAGE(page_zone(page) != zone, page);
- order = page_order(page);
+ order = buddy_order(page);
move_to_free_list(page, zone, order, migratetype);
page += 1 << order;
pages_moved += 1 << order;
@@ -2470,7 +2470,7 @@ static inline void boost_watermark(struc
static void steal_suitable_fallback(struct zone *zone, struct page *page,
unsigned int alloc_flags, int start_type, bool whole_block)
{
- unsigned int current_order = page_order(page);
+ unsigned int current_order = buddy_order(page);
int free_pages, movable_pages, alike_pages;
int old_block_type;
@@ -8296,7 +8296,7 @@ struct page *has_unmovable_pages(struct
*/
if (!page_ref_count(page)) {
if (PageBuddy(page))
- iter += (1 << page_order(page)) - 1;
+ iter += (1 << buddy_order(page)) - 1;
continue;
}
@@ -8509,7 +8509,7 @@ int alloc_contig_range(unsigned long sta
}
if (outer_start != start) {
- order = page_order(pfn_to_page(outer_start));
+ order = buddy_order(pfn_to_page(outer_start));
/*
* outer_start page could be small order buddy page and
@@ -8734,7 +8734,7 @@ void __offline_isolated_pages(unsigned l
BUG_ON(page_count(page));
BUG_ON(!PageBuddy(page));
- order = page_order(page);
+ order = buddy_order(page);
del_page_from_free_list(page, zone, order);
pfn += (1 << order);
}
@@ -8753,7 +8753,7 @@ bool is_free_buddy_page(struct page *pag
for (order = 0; order < MAX_ORDER; order++) {
struct page *page_head = page - (pfn & ((1 << order) - 1));
- if (PageBuddy(page_head) && page_order(page_head) >= order)
+ if (PageBuddy(page_head) && buddy_order(page_head) >= order)
break;
}
spin_unlock_irqrestore(&zone->lock, flags);
@@ -8790,7 +8790,7 @@ static void break_down_buddy_pages(struc
if (current_buddy != target) {
add_to_free_list(current_buddy, zone, high, migratetype);
- set_page_order(current_buddy, high);
+ set_buddy_order(current_buddy, high);
page = next_page;
}
}
@@ -8810,16 +8810,16 @@ bool take_page_off_buddy(struct page *pa
spin_lock_irqsave(&zone->lock, flags);
for (order = 0; order < MAX_ORDER; order++) {
struct page *page_head = page - (pfn & ((1 << order) - 1));
- int buddy_order = page_order(page_head);
+ int page_order = buddy_order(page_head);
- if (PageBuddy(page_head) && buddy_order >= order) {
+ if (PageBuddy(page_head) && page_order >= order) {
unsigned long pfn_head = page_to_pfn(page_head);
int migratetype = get_pfnblock_migratetype(page_head,
pfn_head);
- del_page_from_free_list(page_head, zone, buddy_order);
+ del_page_from_free_list(page_head, zone, page_order);
break_down_buddy_pages(zone, page_head, page, 0,
- buddy_order, migratetype);
+ page_order, migratetype);
ret = true;
break;
}
--- a/mm/page_isolation.c~mm-rename-page_order-to-buddy_order
+++ a/mm/page_isolation.c
@@ -88,7 +88,7 @@ static void unset_migratetype_isolate(st
* these pages to be merged.
*/
if (PageBuddy(page)) {
- order = page_order(page);
+ order = buddy_order(page);
if (order >= pageblock_order) {
pfn = page_to_pfn(page);
buddy_pfn = __find_buddy_pfn(pfn, order);
@@ -256,7 +256,7 @@ __test_page_isolated_in_pageblock(unsign
* the correct MIGRATE_ISOLATE freelist. There is no
* simple way to verify that as VM_BUG_ON(), though.
*/
- pfn += 1 << page_order(page);
+ pfn += 1 << buddy_order(page);
else if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
/* A HWPoisoned page cannot be also PageBuddy */
pfn++;
--- a/mm/page_owner.c~mm-rename-page_order-to-buddy_order
+++ a/mm/page_owner.c
@@ -295,7 +295,7 @@ void pagetypeinfo_showmixedcount_print(s
if (PageBuddy(page)) {
unsigned long freepage_order;
- freepage_order = page_order_unsafe(page);
+ freepage_order = buddy_order_unsafe(page);
if (freepage_order < MAX_ORDER)
pfn += (1UL << freepage_order) - 1;
continue;
@@ -490,7 +490,7 @@ read_page_owner(struct file *file, char
page = pfn_to_page(pfn);
if (PageBuddy(page)) {
- unsigned long freepage_order = page_order_unsafe(page);
+ unsigned long freepage_order = buddy_order_unsafe(page);
if (freepage_order < MAX_ORDER)
pfn += (1UL << freepage_order) - 1;
@@ -584,7 +584,7 @@ static void init_pages_in_zone(pg_data_t
* heavy lock contention.
*/
if (PageBuddy(page)) {
- unsigned long order = page_order_unsafe(page);
+ unsigned long order = buddy_order_unsafe(page);
if (order > 0 && order < MAX_ORDER)
pfn += (1UL << order) - 1;
--- a/mm/page_reporting.c~mm-rename-page_order-to-buddy_order
+++ a/mm/page_reporting.c
@@ -92,7 +92,7 @@ page_reporting_drain(struct page_reporti
* report on the new larger page when we make our way
* up to that higher order.
*/
- if (PageBuddy(page) && page_order(page) == order)
+ if (PageBuddy(page) && buddy_order(page) == order)
__SetPageReported(page);
} while ((sg = sg_next(sg)));
--- a/mm/shuffle.c~mm-rename-page_order-to-buddy_order
+++ a/mm/shuffle.c
@@ -60,7 +60,7 @@ static struct page * __meminit shuffle_v
* ...is the page on the same list as the page we will
* shuffle it with?
*/
- if (page_order(page) != order)
+ if (buddy_order(page) != order)
return NULL;
return page;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-debug-do-not-dereference-i_ino-blindly.patch
mm-factor-find_get_incore_page-out-of-mincore_page.patch
mm-use-find_get_incore_page-in-memcontrol.patch
mm-optimise-madvise-willneed.patch
mm-optimise-madvise-willneed-fix.patch
proc-optimise-smaps-for-shmem-entries.patch
i915-use-find_lock_page-instead-of-find_lock_entry.patch
mm-convert-find_get_entry-to-return-the-head-page.patch
mm-convert-find_get_entry-to-return-the-head-page-fix.patch
mm-shmem-return-head-page-from-find_lock_entry.patch
mm-shmem-return-head-page-from-find_lock_entry-fix.patch
mm-add-find_lock_head.patch
mm-filemap-fix-filemap_map_pages-for-thp.patch
mm-account-pmd-tables-like-pte-tables.patch
mm-move-pagedoublemap-bit.patch
mm-simplify-pagedoublemap-with-pf_second-policy.patch
page_alloc-fix-freeing-non-compound-pages.patch
xarray-add-xa_get_order.patch
xarray-add-xas_split.patch
xarray-add-xas_split-fix-2.patch
xarray-add-xas_split-fix-3patch.patch
mm-filemap-fix-storing-to-a-thp-shadow-entry.patch
mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
mm-memory-remove-page-fault-assumption-of-compound-page-size.patch
mm-memory-remove-page-fault-assumption-of-compound-page-size-fix.patch
mm-page_owner-change-split_page_owner-to-take-a-count.patch
mm-huge_memory-fix-page_trans_huge_mapcount-assumption-of-thp-size.patch
mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch
mm-rmap-fix-assumptions-of-thp-size.patch
mm-truncate-fix-truncation-for-pages-of-arbitrary-size.patch
mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch
mm-vmscan-allow-arbitrary-sized-pages-to-be-paged-out.patch
fs-add-a-filesystem-flag-for-thps.patch
fs-do-not-update-nr_thps-for-mappings-which-support-thps.patch
mm-readahead-add-define_readahead.patch
mm-readahead-make-page_cache_ra_unbounded-take-a-readahead_control.patch
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
mm-readahead-add-page_cache_sync_ra-and-page_cache_async_ra.patch
mm-rename-page_order-to-buddy_order.patch
ramfs-fix-nommu-mmap-with-gaps-in-the-page-cache.patch
harden-autofs-ioctl-table.patch
mm-update-the-documentation-for-vfree.patch
