From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm/filemap: don't relock the page after calling readpage
We don't need to get the page lock again; we just need to wait for the I/O
to finish, so use wait_on_page_locked_killable() like the other callers of
->readpage.
Link: https://lkml.kernel.org/r/20210122160140.223228-17-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Kent Overstreet <redacted>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/filemap.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
--- a/mm/filemap.c~mm-filemap-dont-relock-the-page-after-calling-readpage
+++ a/mm/filemap.c
@@ -2214,23 +2214,16 @@ static int filemap_read_page(struct file
error = mapping->a_ops->readpage(file, page);
if (error)
return error;
- if (PageUptodate(page))
- return 0;
- error = lock_page_killable(page);
+ error = wait_on_page_locked_killable(page);
if (error)
return error;
- if (!PageUptodate(page)) {
- if (page->mapping == NULL) {
- /* page truncated */
- error = AOP_TRUNCATED_PAGE;
- } else {
- shrink_readahead_size_eio(&file->f_ra);
- error = -EIO;
- }
- }
- unlock_page(page);
- return error;
+ if (PageUptodate(page))
+ return 0;
+ if (!page->mapping) /* page truncated */
+ return AOP_TRUNCATED_PAGE;
+ shrink_readahead_size_eio(&file->f_ra);
+ return -EIO;
}
static bool filemap_range_uptodate(struct address_space *mapping,_