From patchwork Tue Nov 10 21:37:34 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 11895447 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7BA7D15E6 for ; Tue, 10 Nov 2020 21:48:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5305820809 for ; Tue, 10 Nov 2020 21:48:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="2vhSaU5s" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731952AbgKJVsB (ORCPT ); Tue, 10 Nov 2020 16:48:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:43122 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731962AbgKJVsB (ORCPT ); Tue, 10 Nov 2020 16:48:01 -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 3F79A20797 for ; Tue, 10 Nov 2020 21:48:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605044880; bh=yn70WelJVJ56UlwcyxZA/bBg3OV27GIP6zbYeFXJYYI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=2vhSaU5sZ+iQQSTBj9MffdJoOZp1p3rMOwCfbz1s9ZhKaD8eYdOSgpXGxMujin/CD MHv+DvaP4jnVYXV3xLJRL4J2w/+4fYzhoLrvV36svyBLMEPjDp9d54kKhI9rkMKjh8 UIbsPa3gcloa9N2FV3jmTFpveBMtAXdjUfYVxTjM= From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH v5 15/22] NFS: Reduce readdir stack usage Date: Tue, 10 Nov 2020 16:37:34 -0500 Message-Id: <20201110213741.860745-16-trondmy@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201110213741.860745-15-trondmy@kernel.org> References: <20201110213741.860745-1-trondmy@kernel.org> <20201110213741.860745-2-trondmy@kernel.org> <20201110213741.860745-3-trondmy@kernel.org> <20201110213741.860745-4-trondmy@kernel.org> <20201110213741.860745-5-trondmy@kernel.org> <20201110213741.860745-6-trondmy@kernel.org> <20201110213741.860745-7-trondmy@kernel.org> <20201110213741.860745-8-trondmy@kernel.org> <20201110213741.860745-9-trondmy@kernel.org> <20201110213741.860745-10-trondmy@kernel.org> <20201110213741.860745-11-trondmy@kernel.org> <20201110213741.860745-12-trondmy@kernel.org> <20201110213741.860745-13-trondmy@kernel.org> <20201110213741.860745-14-trondmy@kernel.org> <20201110213741.860745-15-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust The descriptor and the struct nfs_entry are both large structures, so don't allocate them from the stack. Signed-off-by: Trond Myklebust Reviewed-by: Benjamin Coddington Tested-by: Benjamin Coddington --- fs/nfs/dir.c | 58 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 33 insertions(+), 25 deletions(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 48856cee10de..c3af54640f6c 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -761,23 +761,24 @@ static int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, struct inode *inode) { struct page **pages; - struct nfs_entry entry; + struct nfs_entry *entry; size_t array_size; size_t dtsize = NFS_SERVER(inode)->dtsize; int status = -ENOMEM; - entry.prev_cookie = 0; - entry.cookie = nfs_readdir_page_last_cookie(page); - entry.eof = 0; - entry.fh = nfs_alloc_fhandle(); - entry.fattr = nfs_alloc_fattr(); - entry.server = NFS_SERVER(inode); - if (entry.fh == NULL || entry.fattr == NULL) + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + entry->cookie = nfs_readdir_page_last_cookie(page); + entry->fh = nfs_alloc_fhandle(); + entry->fattr = nfs_alloc_fattr(); + entry->server = NFS_SERVER(inode); + if (entry->fh == NULL || entry->fattr == NULL) goto out; - entry.label = nfs4_label_alloc(NFS_SERVER(inode), GFP_NOWAIT); - if (IS_ERR(entry.label)) { - status = PTR_ERR(entry.label); + entry->label = nfs4_label_alloc(NFS_SERVER(inode), GFP_NOWAIT); + if (IS_ERR(entry->label)) { + status = PTR_ERR(entry->label); goto out; } @@ -788,7 +789,7 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, do { unsigned int pglen; - status = nfs_readdir_xdr_filler(desc, entry.cookie, + status = nfs_readdir_xdr_filler(desc, entry->cookie, pages, dtsize); if (status < 0) break; @@ -799,15 +800,16 @@ int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, break; } - status = nfs_readdir_page_filler(desc, &entry, pages, page, pglen); + status = nfs_readdir_page_filler(desc, entry, pages, page, pglen); } while (!status && nfs_readdir_page_needs_filling(page)); nfs_readdir_free_pages(pages, array_size); out_release_label: - nfs4_label_free(entry.label); + nfs4_label_free(entry->label); out: - nfs_free_fattr(entry.fattr); - nfs_free_fhandle(entry.fh); + nfs_free_fattr(entry->fattr); + nfs_free_fhandle(entry->fh); + kfree(entry); return status; } @@ -974,13 +976,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) struct dentry *dentry = file_dentry(file); struct inode *inode = d_inode(dentry); struct nfs_open_dir_context *dir_ctx = file->private_data; - nfs_readdir_descriptor_t my_desc = { - .file = file, - .ctx = ctx, - .plus = nfs_use_readdirplus(inode, ctx), - }, - *desc = &my_desc; - int res = 0; + struct nfs_readdir_descriptor *desc; + int res; dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n", file, (long long)ctx->pos); @@ -992,10 +989,19 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) * to either find the entry with the appropriate number or * revalidate the cookie. */ - if (ctx->pos == 0 || nfs_attribute_cache_expired(inode)) + if (ctx->pos == 0 || nfs_attribute_cache_expired(inode)) { res = nfs_revalidate_mapping(inode, file->f_mapping); - if (res < 0) + if (res < 0) + goto out; + } + + res = -ENOMEM; + desc = kzalloc(sizeof(*desc), GFP_KERNEL); + if (!desc) goto out; + desc->file = file; + desc->ctx = ctx; + desc->plus = nfs_use_readdirplus(inode, ctx); spin_lock(&file->f_lock); desc->dir_cookie = dir_ctx->dir_cookie; @@ -1040,6 +1046,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx) dir_ctx->attr_gencount = desc->attr_gencount; spin_unlock(&file->f_lock); + kfree(desc); + out: dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file, res); return res;