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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 B5BA7C4742C for ; Sat, 7 Nov 2020 14:13:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 83677206ED for ; Sat, 7 Nov 2020 14:13:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604758431; bh=wXt5qCB83XEP/oviNibsigoWGcbNR1dulLjy896byAY=; h=From:To:Subject:Date:In-Reply-To:References:List-ID:From; b=oToYu1qrlGyP+C4hVk3uwTg5msbhN3Jdexjc6B7u2k4ZggmBG8np28Mu1gIArx/nw bPxKck0FMab4c97OBq+EHprDBPVkQxW05zPG729NCbEZVu3tipFzkOTyNw+S+zpCg+ pm7QoLQSxOhMIRh41Fn6HDzmZtH4FU1aqPN2O1wg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728135AbgKGONu (ORCPT ); Sat, 7 Nov 2020 09:13:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:58254 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728218AbgKGONp (ORCPT ); Sat, 7 Nov 2020 09:13:45 -0500 Received: from localhost.localdomain (c-68-36-133-222.hsd1.mi.comcast.net [68.36.133.222]) (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 273D520719 for ; Sat, 7 Nov 2020 14:13:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604758425; bh=wXt5qCB83XEP/oviNibsigoWGcbNR1dulLjy896byAY=; h=From:To:Subject:Date:In-Reply-To:References:From; b=QtKx0aC6xYXT0lqAwplWPMD4KIUmyuUg2mDhA7/yU5xBXBpCVm2u44LuJ+aYdSug6 IbfVPQAIKMg1ozGCtmf9qpQijSCtcnrT6GHKXQWf0jHQk5bbBSPhHijPVcxsH65Uoa rwkHn2BURsgUIv13sGhbL2vN5GMRPsuv3tUc/P2g= From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH v4 20/21] NFS: Reduce number of RPC calls when doing uncached readdir Date: Sat, 7 Nov 2020 09:03:24 -0500 Message-Id: <20201107140325.281678-21-trondmy@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201107140325.281678-20-trondmy@kernel.org> References: <20201107140325.281678-1-trondmy@kernel.org> <20201107140325.281678-2-trondmy@kernel.org> <20201107140325.281678-3-trondmy@kernel.org> <20201107140325.281678-4-trondmy@kernel.org> <20201107140325.281678-5-trondmy@kernel.org> <20201107140325.281678-6-trondmy@kernel.org> <20201107140325.281678-7-trondmy@kernel.org> <20201107140325.281678-8-trondmy@kernel.org> <20201107140325.281678-9-trondmy@kernel.org> <20201107140325.281678-10-trondmy@kernel.org> <20201107140325.281678-11-trondmy@kernel.org> <20201107140325.281678-12-trondmy@kernel.org> <20201107140325.281678-13-trondmy@kernel.org> <20201107140325.281678-14-trondmy@kernel.org> <20201107140325.281678-15-trondmy@kernel.org> <20201107140325.281678-16-trondmy@kernel.org> <20201107140325.281678-17-trondmy@kernel.org> <20201107140325.281678-18-trondmy@kernel.org> <20201107140325.281678-19-trondmy@kernel.org> <20201107140325.281678-20-trondmy@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust If we're doing uncached readdir, allocate multiple pages in order to try to avoid duplicate RPC calls for the same getdents() call. Signed-off-by: Trond Myklebust --- fs/nfs/dir.c | 79 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 46 insertions(+), 33 deletions(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index b6c3501e8f61..238872d116f7 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -694,12 +694,14 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry, static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc, struct nfs_entry *entry, struct page **xdr_pages, - struct page *fillme, unsigned int buflen) + unsigned int buflen, + struct page **arrays, + size_t narrays) { struct address_space *mapping = desc->file->f_mapping; struct xdr_stream stream; struct xdr_buf buf; - struct page *scratch, *new, *page = fillme; + struct page *scratch, *new, *page = *arrays; int status; scratch = alloc_page(GFP_KERNEL); @@ -725,15 +727,22 @@ static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc, if (status != -ENOSPC) continue; - if (page->mapping != mapping) - break; - new = nfs_readdir_page_get_next(mapping, page->index + 1, - entry->prev_cookie); - if (!new) - break; - if (page != fillme) - nfs_readdir_page_unlock_and_put(page); - page = new; + if (narrays > 1) { + narrays--; + arrays++; + page = *arrays; + } else { + if (page->mapping != mapping) + break; + new = nfs_readdir_page_get_next(mapping, + page->index + 1, + entry->prev_cookie); + if (!new) + break; + if (page != *arrays) + nfs_readdir_page_unlock_and_put(page); + page = new; + } status = nfs_readdir_add_to_array(entry, page); } while (!status && !entry->eof); @@ -750,7 +759,7 @@ static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc, break; } - if (page != fillme) + if (page != *arrays) nfs_readdir_page_unlock_and_put(page); put_page(scratch); @@ -790,10 +799,11 @@ static struct page **nfs_readdir_alloc_pages(size_t npages) } static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc, - struct page *page, __be32 *verf_arg, - __be32 *verf_res) + __be32 *verf_arg, __be32 *verf_res, + struct page **arrays, size_t narrays) { struct page **pages; + struct page *page = *arrays; struct nfs_entry *entry; size_t array_size; struct inode *inode = file_inode(desc->file); @@ -835,7 +845,8 @@ static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc, break; } - status = nfs_readdir_page_filler(desc, entry, pages, page, pglen); + status = nfs_readdir_page_filler(desc, entry, pages, pglen, + arrays, narrays); } while (!status && nfs_readdir_page_needs_filling(page)); nfs_readdir_free_pages(pages, array_size); @@ -884,8 +895,8 @@ static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc) if (!desc->page) return -ENOMEM; if (nfs_readdir_page_needs_filling(desc->page)) { - res = nfs_readdir_xdr_to_array(desc, desc->page, - nfsi->cookieverf, verf); + res = nfs_readdir_xdr_to_array(desc, nfsi->cookieverf, verf, + &desc->page, 1); if (res < 0) { nfs_readdir_page_unlock_and_put_cached(desc); if (res == -EBADCOOKIE || res == -ENOTSYNC) { @@ -976,35 +987,37 @@ static void nfs_do_filldir(struct nfs_readdir_descriptor *desc) */ static int uncached_readdir(struct nfs_readdir_descriptor *desc) { - struct page *page = NULL; + struct page **arrays; + size_t i, sz = 16; __be32 verf[NFS_DIR_VERIFIER_SIZE]; int status; dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n", (unsigned long long)desc->dir_cookie); - page = alloc_page(GFP_HIGHUSER); - if (!page) { - status = -ENOMEM; - goto out; - } + arrays = nfs_readdir_alloc_pages(sz); + if (!arrays) + return -ENOMEM; + for (i = 0; i < sz; i++) + nfs_readdir_page_init_array(arrays[i], desc->dir_cookie); desc->page_index = 0; desc->last_cookie = desc->dir_cookie; - desc->page = page; desc->duped = 0; - nfs_readdir_page_init_array(page, desc->dir_cookie); - status = nfs_readdir_xdr_to_array(desc, page, desc->verf, verf); - if (status < 0) - goto out_release; + status = nfs_readdir_xdr_to_array(desc, desc->verf, verf, arrays, sz); - nfs_do_filldir(desc); + for (i = 0; !desc->eof && i < sz; i++) { + desc->page = arrays[i]; + nfs_do_filldir(desc); + } + desc->page = NULL; + + + for (i = 0; i < sz; i++) + nfs_readdir_clear_array(arrays[i]); + nfs_readdir_free_pages(arrays, sz); - out_release: - nfs_readdir_clear_array(desc->page); - nfs_readdir_page_put(desc); - out: dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status); return status; -- 2.28.0