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: ZhangPeng <zhangpeng362@huawei.com>
Reviewed-by Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Muchun 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: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
ZhangPeng 2023-06-06 14:20:13 +08:00 committed by Andrew Morton
parent 959a78b6dd
commit 061e62e818

View File

@ -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 @@ out_mutex:
* here without taking refcount.
*/
if (need_wait_lock)
wait_on_page_locked(page);
folio_wait_locked(folio);
return ret;
}