From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Kent Overstreet <kent.overstreet@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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, _
