mm: introduce compound_nr()
Replace 1 << compound_order(page) with compound_nr(page). Minor
improvements in readability.
Link: http://lkml.kernel.org/r/20190721104612.19120-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index 4c7ebe0..6d89db7 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -208,13 +208,13 @@ void __flush_dcache_page(struct address_space *mapping, struct page *page)
} else {
unsigned long i;
if (cache_is_vipt_nonaliasing()) {
- for (i = 0; i < (1 << compound_order(page)); i++) {
+ for (i = 0; i < compound_nr(page); i++) {
void *addr = kmap_atomic(page + i);
__cpuc_flush_dcache_area(addr, PAGE_SIZE);
kunmap_atomic(addr);
}
} else {
- for (i = 0; i < (1 << compound_order(page)); i++) {
+ for (i = 0; i < compound_nr(page); i++) {
void *addr = kmap_high_get(page + i);
if (addr) {
__cpuc_flush_dcache_area(addr, PAGE_SIZE);
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a8953f1..73d4873f 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -667,7 +667,7 @@ void flush_dcache_icache_hugepage(struct page *page)
BUG_ON(!PageCompound(page));
- for (i = 0; i < (1UL << compound_order(page)); i++) {
+ for (i = 0; i < compound_nr(page); i++) {
if (!PageHighMem(page)) {
__flush_dcache_icache(page_address(page+i));
} else {
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index bf43d1d..ea16304 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -461,7 +461,7 @@ static void smaps_page_accumulate(struct mem_size_stats *mss,
static void smaps_account(struct mem_size_stats *mss, struct page *page,
bool compound, bool young, bool dirty, bool locked)
{
- int i, nr = compound ? 1 << compound_order(page) : 1;
+ int i, nr = compound ? compound_nr(page) : 1;
unsigned long size = nr * PAGE_SIZE;
/*
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 9238548..69b7314 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -805,6 +805,12 @@ static inline void set_compound_order(struct page *page, unsigned int order)
page[1].compound_order = order;
}
+/* Returns the number of pages in this potentially compound page. */
+static inline unsigned long compound_nr(struct page *page)
+{
+ return 1UL << compound_order(page);
+}
+
/* Returns the number of bytes in this potentially compound page. */
static inline unsigned long page_size(struct page *page)
{
diff --git a/mm/compaction.c b/mm/compaction.c
index 952dc2f..777c088 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -969,7 +969,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
* is safe to read and it's 0 for tail pages.
*/
if (unlikely(PageCompound(page))) {
- low_pfn += (1UL << compound_order(page)) - 1;
+ low_pfn += compound_nr(page) - 1;
goto isolate_fail;
}
}
diff --git a/mm/filemap.c b/mm/filemap.c
index 40667c2..5f30aed 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -126,7 +126,7 @@ static void page_cache_delete(struct address_space *mapping,
/* hugetlb pages are represented by a single entry in the xarray */
if (!PageHuge(page)) {
xas_set_order(&xas, page->index, compound_order(page));
- nr = 1U << compound_order(page);
+ nr = compound_nr(page);
}
VM_BUG_ON_PAGE(!PageLocked(page), page);
diff --git a/mm/gup.c b/mm/gup.c
index 98f13ab..84a36d8 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1460,7 +1460,7 @@ static long check_and_migrate_cma_pages(struct task_struct *tsk,
* gup may start from a tail page. Advance step by the left
* part.
*/
- step = (1 << compound_order(head)) - (pages[i] - head);
+ step = compound_nr(head) - (pages[i] - head);
/*
* If we get a page from the CMA zone, since we are going to
* be pinning these entries, we might as well move them out
diff --git a/mm/hugetlb_cgroup.c b/mm/hugetlb_cgroup.c
index 68c2f2f..f1930fa 100644
--- a/mm/hugetlb_cgroup.c
+++ b/mm/hugetlb_cgroup.c
@@ -139,7 +139,7 @@ static void hugetlb_cgroup_move_parent(int idx, struct hugetlb_cgroup *h_cg,
if (!page_hcg || page_hcg != h_cg)
goto out;
- nr_pages = 1 << compound_order(page);
+ nr_pages = compound_nr(page);
if (!parent) {
parent = root_h_cgroup;
/* root has no limit */
diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index 307631d..6814d6d 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -336,7 +336,7 @@ void kasan_poison_slab(struct page *page)
{
unsigned long i;
- for (i = 0; i < (1 << compound_order(page)); i++)
+ for (i = 0; i < compound_nr(page); i++)
page_kasan_tag_reset(page + i);
kasan_poison_shadow(page_address(page), page_size(page),
KASAN_KMALLOC_REDZONE);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f3c15bb..6c6032c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6511,7 +6511,7 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
unsigned int nr_pages = 1;
if (PageTransHuge(page)) {
- nr_pages <<= compound_order(page);
+ nr_pages = compound_nr(page);
ug->nr_huge += nr_pages;
}
if (PageAnon(page))
@@ -6523,7 +6523,7 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
}
ug->pgpgout++;
} else {
- ug->nr_kmem += 1 << compound_order(page);
+ ug->nr_kmem += compound_nr(page);
__ClearPageKmemcg(page);
}
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index c73f099..5f2c83c 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1309,7 +1309,7 @@ static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
head = compound_head(page);
if (page_huge_active(head))
return pfn;
- skip = (1 << compound_order(head)) - (page - head);
+ skip = compound_nr(head) - (page - head);
pfn += skip - 1;
}
return 0;
@@ -1347,7 +1347,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
if (PageHuge(page)) {
struct page *head = compound_head(page);
- pfn = page_to_pfn(head) + (1<<compound_order(head)) - 1;
+ pfn = page_to_pfn(head) + compound_nr(head) - 1;
isolate_huge_page(head, &source);
continue;
} else if (PageTransHuge(page))
diff --git a/mm/migrate.c b/mm/migrate.c
index 9f4ed4e..aa72b49 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1892,7 +1892,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page);
/* Avoid migrating to a node that is nearly full */
- if (!migrate_balanced_pgdat(pgdat, 1UL << compound_order(page)))
+ if (!migrate_balanced_pgdat(pgdat, compound_nr(page)))
return 0;
if (isolate_lru_page(page))
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ff5484f..df566c0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8196,7 +8196,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
if (!hugepage_migration_supported(page_hstate(head)))
goto unmovable;
- skip_pages = (1 << compound_order(head)) - (page - head);
+ skip_pages = compound_nr(head) - (page - head);
iter += skip_pages - 1;
continue;
}
diff --git a/mm/rmap.c b/mm/rmap.c
index f401732..2600644 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1520,8 +1520,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) {
pteval = swp_entry_to_pte(make_hwpoison_entry(subpage));
if (PageHuge(page)) {
- int nr = 1 << compound_order(page);
- hugetlb_count_sub(nr, mm);
+ hugetlb_count_sub(compound_nr(page), mm);
set_huge_swap_pte_at(mm, address,
pvmw.pte, pteval,
vma_mmu_pagesize(vma));
diff --git a/mm/shmem.c b/mm/shmem.c
index 0f7fd4a..15d26c8 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -609,7 +609,7 @@ static int shmem_add_to_page_cache(struct page *page,
{
XA_STATE_ORDER(xas, &mapping->i_pages, index, compound_order(page));
unsigned long i = 0;
- unsigned long nr = 1UL << compound_order(page);
+ unsigned long nr = compound_nr(page);
VM_BUG_ON_PAGE(PageTail(page), page);
VM_BUG_ON_PAGE(index != round_down(index, nr), page);
@@ -1884,7 +1884,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
lru_cache_add_anon(page);
spin_lock_irq(&info->lock);
- info->alloced += 1 << compound_order(page);
+ info->alloced += compound_nr(page);
inode->i_blocks += BLOCKS_PER_PAGE << compound_order(page);
shmem_recalc_inode(inode);
spin_unlock_irq(&info->lock);
@@ -1925,7 +1925,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
struct page *head = compound_head(page);
int i;
- for (i = 0; i < (1 << compound_order(head)); i++) {
+ for (i = 0; i < compound_nr(head); i++) {
clear_highpage(head + i);
flush_dcache_page(head + i);
}
@@ -1952,7 +1952,7 @@ static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
* Error recovery.
*/
unacct:
- shmem_inode_unacct_blocks(inode, 1 << compound_order(page));
+ shmem_inode_unacct_blocks(inode, compound_nr(page));
if (PageTransHuge(page)) {
unlock_page(page);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 8368621..f844af5 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -116,7 +116,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp)
struct address_space *address_space = swap_address_space(entry);
pgoff_t idx = swp_offset(entry);
XA_STATE_ORDER(xas, &address_space->i_pages, idx, compound_order(page));
- unsigned long i, nr = 1UL << compound_order(page);
+ unsigned long i, nr = compound_nr(page);
VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON_PAGE(PageSwapCache(page), page);
diff --git a/mm/util.c b/mm/util.c
index e6351a8..bab284d 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -521,7 +521,7 @@ bool page_mapped(struct page *page)
return true;
if (PageHuge(page))
return false;
- for (i = 0; i < (1 << compound_order(page)); i++) {
+ for (i = 0; i < compound_nr(page); i++) {
if (atomic_read(&page[i]._mapcount) >= 0)
return true;
}
diff --git a/mm/vmscan.c b/mm/vmscan.c
index a6c5d0b..8e03427 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1149,7 +1149,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
VM_BUG_ON_PAGE(PageActive(page), page);
- nr_pages = 1 << compound_order(page);
+ nr_pages = compound_nr(page);
/* Account the number of base pages even though THP */
sc->nr_scanned += nr_pages;
@@ -1705,7 +1705,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
VM_BUG_ON_PAGE(!PageLRU(page), page);
- nr_pages = 1 << compound_order(page);
+ nr_pages = compound_nr(page);
total_scan += nr_pages;
if (page_zonenum(page) > sc->reclaim_idx) {