From patchwork Mon Oct 5 11:02:33 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 7326561 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id B35C8BEEA4 for ; Mon, 5 Oct 2015 11:03:53 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2AA6E206EB for ; Mon, 5 Oct 2015 11:03:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0B918206F8 for ; Mon, 5 Oct 2015 11:03:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751265AbbJELDj (ORCPT ); Mon, 5 Oct 2015 07:03:39 -0400 Received: from mail-qg0-f52.google.com ([209.85.192.52]:36225 "EHLO mail-qg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750979AbbJELDA (ORCPT ); Mon, 5 Oct 2015 07:03:00 -0400 Received: by qgx61 with SMTP id 61so145874645qgx.3 for ; Mon, 05 Oct 2015 04:02:59 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=7FXDAKOBflpfDXMQzWjU+TUzWICAEPkWsIxdQShn5/4=; b=eDX8rPyxSeSzAc1gGEOhWMV6Lb6XoLbqXaPhk45zl4H/n3s7exyur1yr5X1Ixq3mTF 882i2swSqQWcSxnGQRo/7C3O+nQzvu1uDNqAl2kyYrd1eNGGICwTisG4qvjO2J+UP9Ql YWnfKMg+BmyBks7xaFxe4nxssGUJ6G3ORCzb1RdZrBaD5Her93UEkCIdeSQsRwuoCdFg N9TrxWyDKhV1pxOM+zPAwJXXvoHQfzOvwQeNlSfx8q77JA09PijP+HfcFoWQ7uueXkGH QhUFl9A0nZXKF2S9xUb1mpOZBSFrYEH6obu1tY+v4BuqA6L3EVMriBoZrE5Mhieq7x7b QMhQ== X-Gm-Message-State: ALoCoQl8ua6PZpZrhYb1s1wDzHsKz73Rz598KzU0h+XDK03qQwLrEpJerzmGziGFytCs11ZR68f1 X-Received: by 10.140.131.135 with SMTP id 129mr41430488qhd.31.1444042979292; Mon, 05 Oct 2015 04:02:59 -0700 (PDT) Received: from tlielax.poochiereds.net ([2606:a000:1125:6079::d5a]) by smtp.googlemail.com with ESMTPSA id p39sm4977719qkp.47.2015.10.05.04.02.58 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 05 Oct 2015 04:02:58 -0700 (PDT) From: Jeff Layton X-Google-Original-From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Al Viro Subject: [PATCH v5 11/20] nfsd: keep some rudimentary stats on nfsd_file cache Date: Mon, 5 Oct 2015 07:02:33 -0400 Message-Id: <1444042962-6947-12-git-send-email-jeff.layton@primarydata.com> X-Mailer: git-send-email 2.4.3 In-Reply-To: <1444042962-6947-1-git-send-email-jeff.layton@primarydata.com> References: <1444042962-6947-1-git-send-email-jeff.layton@primarydata.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Per chain count and max length, protected by the per-chain spinlock. When the file is read, we walk the array of buckets and fetch the count from each. Signed-off-by: Jeff Layton --- fs/nfsd/filecache.c | 40 ++++++++++++++++++++++++++++++++++++++++ fs/nfsd/filecache.h | 1 + fs/nfsd/nfsctl.c | 10 ++++++++++ 3 files changed, 51 insertions(+) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index fcbc3bca3bdc..932b58a5774f 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -11,6 +11,7 @@ #include #include #include +#include #include "vfs.h" #include "nfsd.h" @@ -30,6 +31,8 @@ struct nfsd_fcache_bucket { struct hlist_head nfb_head; spinlock_t nfb_lock; + unsigned int nfb_count; + unsigned int nfb_maxcount; }; static struct kmem_cache *nfsd_file_slab; @@ -111,6 +114,7 @@ nfsd_file_unhash(struct nfsd_file *nf) trace_nfsd_file_unhash(nf); if (test_bit(NFSD_FILE_HASHED, &nf->nf_flags)) { + --nfsd_file_hashtbl[nf->nf_hashval].nfb_count; clear_bit(NFSD_FILE_HASHED, &nf->nf_flags); hlist_del_rcu(&nf->nf_node); list_lru_del(&nfsd_file_lru, &nf->nf_lru); @@ -491,6 +495,9 @@ retry: list_lru_add(&nfsd_file_lru, &new->nf_lru); hlist_add_head_rcu(&new->nf_node, &nfsd_file_hashtbl[hashval].nfb_head); + ++nfsd_file_hashtbl[hashval].nfb_count; + nfsd_file_hashtbl[hashval].nfb_maxcount = max(nfsd_file_hashtbl[hashval].nfb_maxcount, + nfsd_file_hashtbl[hashval].nfb_count); spin_unlock(&nfsd_file_hashtbl[hashval].nfb_lock); /* This should never fail since we set allow_dups to true */ @@ -571,3 +578,36 @@ open_file: wake_up_bit(&nf->nf_flags, NFSD_FILE_PENDING); goto out; } + +/* + * Note that fields may be added, removed or reordered in the future. Programs + * scraping this file for info should test the labels to ensure they're + * getting the correct field. + */ +static int nfsd_file_cache_stats_show(struct seq_file *m, void *v) +{ + unsigned int i, count = 0, longest = 0; + + /* + * No need for spinlocks here since we're not terribly interested in + * accuracy. We do take the nfsd_mutex simply to ensure that we + * don't end up racing with server shutdown + */ + mutex_lock(&nfsd_mutex); + if (nfsd_file_hashtbl) { + for (i = 0; i < NFSD_FILE_HASH_SIZE; i++) { + count += nfsd_file_hashtbl[i].nfb_count; + longest = max(longest, nfsd_file_hashtbl[i].nfb_count); + } + } + mutex_unlock(&nfsd_mutex); + + seq_printf(m, "total entries: %u\n", count); + seq_printf(m, "longest chain: %u\n", longest); + return 0; +} + +int nfsd_file_cache_stats_open(struct inode *inode, struct file *file) +{ + return single_open(file, nfsd_file_cache_stats_show, NULL); +} diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index 5c871c3114f2..a1467dbf1d29 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -34,4 +34,5 @@ struct nfsd_file *nfsd_file_get(struct nfsd_file *nf); void nfsd_file_close_inode_sync(struct inode *inode); __be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct nfsd_file **nfp); +int nfsd_file_cache_stats_open(struct inode *, struct file *); #endif /* _FS_NFSD_FILECACHE_H */ diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 9690cb4dd588..eff44a277f70 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -22,6 +22,7 @@ #include "state.h" #include "netns.h" #include "pnfs.h" +#include "filecache.h" /* * We have a single directory with several nodes in it. @@ -36,6 +37,7 @@ enum { NFSD_Threads, NFSD_Pool_Threads, NFSD_Pool_Stats, + NFSD_File_Cache_Stats, NFSD_Reply_Cache_Stats, NFSD_Versions, NFSD_Ports, @@ -220,6 +222,13 @@ static const struct file_operations pool_stats_operations = { .owner = THIS_MODULE, }; +static struct file_operations file_cache_stats_operations = { + .open = nfsd_file_cache_stats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + static struct file_operations reply_cache_stats_operations = { .open = nfsd_reply_cache_stats_open, .read = seq_read, @@ -1138,6 +1147,7 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent) [NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Pool_Stats] = {"pool_stats", &pool_stats_operations, S_IRUGO}, + [NFSD_File_Cache_Stats] = {"file_cache_stats", &file_cache_stats_operations, S_IRUGO}, [NFSD_Reply_Cache_Stats] = {"reply_cache_stats", &reply_cache_stats_operations, S_IRUGO}, [NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Ports] = {"portlist", &transaction_ops, S_IWUSR|S_IRUGO},