Due to the change about how block layer detects congestion the
justification of commit 8fd2e0b505d1 ("mm: swap: check if swap backing device
is congested or not") doesn't stand anymore, so the commit could be just
reverted in order to solve the race reported by commit 2efa33fc7f6e ("mm/shmem:
fix shmem_swapin() race with swapoff"), so the fix commit could be just
reverted as well.
Suggested-by: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Signed-off-by: Yang Shi <shy828301@xxxxxxxxx>
---
mm/shmem.c | 14 +-------------
1 file changed, 1 insertion(+), 13 deletions(-)
diff --git a/mm/shmem.c b/mm/shmem.c
index dcc07d14162e..d5427de5bf02 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1699,8 +1699,7 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index,
struct address_space *mapping = inode->i_mapping;
struct shmem_inode_info *info = SHMEM_I(inode);
struct mm_struct *charge_mm = vma ? vma->vm_mm : NULL;
- struct swap_info_struct *si;
- struct page *page = NULL;
+ struct page *page;
swp_entry_t swap;
int error;
@@ -1708,12 +1707,6 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index,
swap = radix_to_swp_entry(*pagep);
*pagep = NULL;
- /* Prevent swapoff from happening to us. */
- si = get_swap_device(swap);
- if (!si) {
- error = EINVAL;
- goto failed;
- }
/* Look it up and read it in.. */
page = lookup_swap_cache(swap, NULL, 0);
if (!page) {
@@ -1775,8 +1768,6 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index,
swap_free(swap);
*pagep = page;
- if (si)
- put_swap_device(si);
return 0;
failed:
if (!shmem_confirm_swap(mapping, index, swap))
@@ -1787,9 +1778,6 @@ static int shmem_swapin_page(struct inode *inode, pgoff_t index,
put_page(page);
}
- if (si)
- put_swap_device(si);
-
return error;
}
--
2.26.2
