Commit 061e62e8 authored by ZhangPeng's avatar ZhangPeng Committed by Andrew Morton
Browse files

mm/hugetlb: use a folio in hugetlb_fault() 

We can replace seven implicit calls to compound_head() with one by using
folio.

[akpm@linux-foundation.org: update comment, per Sidhartha]
Link: https://lkml.kernel.org/r/20230606062013.2947002-4-zhangpeng362@huawei.com


Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
Reviewed-by Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarMuchun Song <songmuchun@bytedance.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 959a78b6

mm/hugetlb.c

+10 −10
Original line number Diff line number Diff line
@@ -6062,7 +6062,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 
	vm_fault_t ret;

	u32 hash;

	pgoff_t idx;

	struct page *page = NULL;

	struct folio *folio = NULL;

	struct folio *pagecache_folio = NULL;

	struct hstate *h = hstate_vma(vma);

	struct address_space *mapping;
@@ -6179,16 +6179,16 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 
	/*

	 * hugetlb_wp() requires page locks of pte_page(entry) and

	 * pagecache_folio, so here we need take the former one

	 * when page != pagecache_folio or !pagecache_folio.

	 * when folio != pagecache_folio or !pagecache_folio.

	 */

	page = pte_page(entry);

	if (page_folio(page) != pagecache_folio)

		if (!trylock_page(page)) {

	folio = page_folio(pte_page(entry));

	if (folio != pagecache_folio)

		if (!folio_trylock(folio)) {

			need_wait_lock = 1;

			goto out_ptl;

		}



	get_page(page);

	folio_get(folio);



	if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) {

		if (!huge_pte_write(entry)) {
@@ -6204,9 +6204,9 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 
						flags & FAULT_FLAG_WRITE))

		update_mmu_cache(vma, haddr, ptep);

out_put_page:

	if (page_folio(page) != pagecache_folio)

		unlock_page(page);

	put_page(page);

	if (folio != pagecache_folio)

		folio_unlock(folio);

	folio_put(folio);

out_ptl:

	spin_unlock(ptl);
@@ -6225,7 +6225,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, 
	 * here without taking refcount.

	 */

	if (need_wait_lock)

		wait_on_page_locked(page);

		folio_wait_locked(folio);

	return ret;

}