Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail.pictura-hosting.nl ([195.93.224.144]:57987 "EHLO mail.pictura-dp.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753005AbaAGTzj (ORCPT ); Tue, 7 Jan 2014 14:55:39 -0500 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Date: Tue, 07 Jan 2014 20:55:12 +0100 From: Sander Klein To: "J. Bruce Fields" Cc: Karel Zak , linux-nfs@vger.kernel.org, linux-nfs-owner@vger.kernel.org Subject: Re: rpc.mountd high cpu usage In-Reply-To: <20140106212514.GG31764@fieldses.org> References: <889b64df295ba04d47f941762ebe0bac@roedie.nl> <20131212154642.GA11521@fieldses.org> <20140106111805.GF4435@x2.net.home> <20140106212514.GG31764@fieldses.org> Message-ID: <0a94c641959a8084a56c688dd2242c04@roedie.nl> Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi, Thank you very much for this patch. I've added the ZFS magic and tested it on my nfs-utils-1.2.8 package and it looks like it fixes my issue. Is there any chance this patch will be accepted upstream with the ZFS_SUPER_MAGIC as shown below? Greets, Sander From e4f5b38c87ef8d713c6d0a3169afaf1acc7e22c6 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Mon, 6 Jan 2014 12:03:01 +0100 Subject: [PATCH] mountd: optimize libblkid usage * use get_uuid_blkdev() only first time for the path (it means that uuid_by_path() is called with type==0) * don't use libblkid for btrfs, network or pseudo filesystems Note that the patch defines the fs type ID rather than include as this file seems incomplete and libc specific). Signed-off-by: Karel Zak --- utils/mountd/cache.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) Index: nfs-utils-1.2.8/utils/mountd/cache.c =================================================================== --- nfs-utils-1.2.8.orig/utils/mountd/cache.c 2013-05-02 14:21:12.000000000 +0200 +++ nfs-utils-1.2.8/utils/mountd/cache.c 2014-01-07 20:46:55.799904557 +0100 @@ -266,6 +266,27 @@ return 1; } + +/* + * Don't ask libblkid for these filesystems. Note that BTRF is ignored, because + * we generate the identifier from statfs->f_fsid. The rest are network or + * pseudo filesystems. (See for the basic IDs.) + */ +static const long int nonblkid_filesystems[] = { + 0x2fc12fc1, /* ZFS_SUPER_MAGIC */ + 0x9123683E, /* BTRFS_SUPER_MAGIC */ + 0xFF534D42, /* CIFS_MAGIC_NUMBER */ + 0x1373, /* DEVFS_SUPER_MAGIC */ + 0x73757245, /* CODA_SUPER_MAGIC */ + 0x564C, /* NCP_SUPER_MAGIC */ + 0x6969, /* NFS_SUPER_MAGIC */ + 0x9FA0, /* PROC_SUPER_MAGIC */ + 0x62656572, /* SYSFS_MAGIC */ + 0x517B, /* SMB_SUPER_MAGIC */ + 0x01021994, /* TMPFS_SUPER_MAGIC */ + 0 /* last */ +}; + static int uuid_by_path(char *path, int type, size_t uuidlen, char *uuid) { /* get a uuid for the filesystem found at 'path'. @@ -297,12 +318,24 @@ */ struct statfs64 st; char fsid_val[17]; - const char *blkid_val; + const char *blkid_val = NULL; const char *val; + int rc; + + rc = statfs64(path, &st); + + if (type == 0 && rc == 0) { + const long int *bad; - blkid_val = get_uuid_blkdev(path); + for (bad = nonblkid_filesystems; *bad; bad++) { + if (*bad == st.f_type) + break; + } + if (*bad == 0) + blkid_val = get_uuid_blkdev(path); + } - if (statfs64(path, &st) == 0 && + if (rc == 0 && (st.f_fsid.__val[0] || st.f_fsid.__val[1])) snprintf(fsid_val, 17, "%08x%08x", st.f_fsid.__val[0], st.f_fsid.__val[1]);