From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34FAAC3F68F for ; Mon, 6 Jan 2020 20:44:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7F8E2081E for ; Mon, 6 Jan 2020 20:44:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578343442; bh=GCDF90PxaFvkCGdMTp6cM9sEWuA1IASP7woryXiIkio=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=dDKuiVLG0w7qgtx3e9nWrCAFWOWSqZAdnh/Gv/ctPgwgeHIhs68RU+tyPMyFdP2wp Nn2apN/Fl2Y302dr3/Z41zP9MhPjc5lYvV97iyU4PHvEyTAKZW3q78+bzBK/OiBLFn GknfjON0xmrhSoTS4g7RmJLfwOPCTak4HjkGKUBw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726723AbgAFUoB (ORCPT ); Mon, 6 Jan 2020 15:44:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:38908 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726657AbgAFUoB (ORCPT ); Mon, 6 Jan 2020 15:44:01 -0500 Received: from gmail.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5BADC20731; Mon, 6 Jan 2020 20:44:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578343440; bh=GCDF90PxaFvkCGdMTp6cM9sEWuA1IASP7woryXiIkio=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kxR3BbcmfEd73kXxSYAqfsOmgdQ2Fcysz9TiL5R0c3beHGBb4GmNNZQGIw8h8advw otmHqxecH+g51yMiinkK+sU1bLicbT7jDFfAd82yOqB1479nS8FFz1NO8GvTpKAp5Z Ti9u2rTBVrn+51T4bSV4dyCcTRYh59GowGLGVluc= Date: Mon, 6 Jan 2020 12:43:58 -0800 From: Eric Biggers To: Jaegeuk Kim Cc: linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Victor Hsieh , linux-f2fs-devel@lists.sourceforge.net Subject: Re: [PATCH] fs-verity: implement readahead of Merkle tree pages Message-ID: <20200106204357.GA254289@gmail.com> References: <20191216181112.89304-1-ebiggers@kernel.org> <20200106181508.GA50058@jaegeuk-macbookpro.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200106181508.GA50058@jaegeuk-macbookpro.roam.corp.google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Mon, Jan 06, 2020 at 10:15:08AM -0800, Jaegeuk Kim wrote: > > static struct page *f2fs_read_merkle_tree_page(struct inode *inode, > > - pgoff_t index) > > + pgoff_t index, > > + unsigned long num_ra_pages) > > { > > + struct page *page; > > + > > index += f2fs_verity_metadata_pos(inode) >> PAGE_SHIFT; > > > > - return read_mapping_page(inode->i_mapping, index, NULL); > > + page = find_get_page(inode->i_mapping, index); > > + if (!page || !PageUptodate(page)) { > > + if (page) > > + put_page(page); > > + else if (num_ra_pages > 1) > > + f2fs_merkle_tree_readahead(inode->i_mapping, index, > > + num_ra_pages); > > + page = read_mapping_page(inode->i_mapping, index, NULL); > > + if (IS_ERR(page)) > > + return page; > > We don't need to check this, but can use the below return page? > Indeed, I'll remove the unnecessary IS_ERR(page) check. > > + } > > mark_page_accessed(page)? > > > + return page; > > } Good idea, but read_mapping_page() already calls mark_page_accessed(). It's just find_get_page() that doesn't. So after this patch, mark_page_accessed() is no longer called in the case where the page is already cached and Uptodate. I'll change it to use: find_get_page_flags(inode->i_mapping, index, FGP_ACCESSED); - Eric