fs: hugetlbfs: set vma policy only when needed for allocating folio

Calling hugetlb_set_vma_policy() later avoids setting the vma policy
and then dropping it on a page cache hit.

Link: https://lkml.kernel.org/r/20230502235622.3652586-1-ackerleytng@google.com
Signed-off-by: Ackerley Tng <ackerleytng@google.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vishal Annapurve <vannapurve@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index ecfdfb2529a36cf7b98914fb7c19f85043eca413..90361a922cec7bb188623a0b830abde1379a1106 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -834,9 +834,6 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
                        break;
                }
 
-               /* Set numa allocation policy based on index */
-               hugetlb_set_vma_policy(&pseudo_vma, inode, index);
-
                /* addr is the offset within the file (zero based) */
                addr = index * hpage_size;
 
@@ -850,7 +847,6 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
                rcu_read_unlock();
                if (present) {
                        mutex_unlock(&hugetlb_fault_mutex_table[hash]);
-                       hugetlb_drop_vma_policy(&pseudo_vma);
                        continue;
                }
 
@@ -862,6 +858,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
                 * folios in these areas, we need to consume the reserves
                 * to keep reservation accounting consistent.
                 */
+               hugetlb_set_vma_policy(&pseudo_vma, inode, index);
                folio = alloc_hugetlb_folio(&pseudo_vma, addr, 0);
                hugetlb_drop_vma_policy(&pseudo_vma);
                if (IS_ERR(folio)) {