From patchwork Thu Jun 5 13:45:00 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 4305451 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id BA825BEEA7 for ; Thu, 5 Jun 2014 13:45:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1E4D42017A for ; Thu, 5 Jun 2014 13:45:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E531A20149 for ; Thu, 5 Jun 2014 13:45:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751581AbaFENpI (ORCPT ); Thu, 5 Jun 2014 09:45:08 -0400 Received: from mail-qa0-f44.google.com ([209.85.216.44]:38069 "EHLO mail-qa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750926AbaFENpH (ORCPT ); Thu, 5 Jun 2014 09:45:07 -0400 Received: by mail-qa0-f44.google.com with SMTP id j7so1359025qaq.31 for ; Thu, 05 Jun 2014 06:45:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id; bh=HulbTDhlg56gmmW3+9X8R3xfCMz73Zxvuwpc7lAaujo=; b=GEQjVb9l5m8hpgLhrUqFkA05c4BQvuhJsH8Ng6R/rrnthXjqcjwyfZfln2o9B5gWwe D/itj7pHe+C869Dk3+60r3b8bflGzD+JWfdQNWOrlCWx5ZKIcTJR1Wy2pqdJ4HFVcqV2 ZUpEzxEittBqPP6ujIF2CUwNB7fD69bdtVYEanA8JxIEheptIrQ7e9JVqf+u/XG0mLRO 2RxD3OjL5AQi+Irh6pPxNpZKeTDGxUVCw1X8AgkO0Vyjq/Z+yYpGnT/MlXkB3SPFYysV NJ5TPzjHYcAndaBOx6gf1krBcnwGzhBhzncznD7kGtY1oQxmaIaaZQlopUNoBc+fLq+o jB7A== X-Gm-Message-State: ALoCoQmAXceTFMJOkNyRtbpcwXegpANiVwvVdq/oac6bIElNx+t6DvYML761ZxE74A5shq3yVjI7 X-Received: by 10.224.3.202 with SMTP id 10mr56369306qao.24.1401975906283; Thu, 05 Jun 2014 06:45:06 -0700 (PDT) Received: from tlielax.poochiereds.net ([2001:470:8:d63:3a60:77ff:fe93:a95d]) by mx.google.com with ESMTPSA id d8sm9527802qas.24.2014.06.05.06.45.04 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 05 Jun 2014 06:45:05 -0700 (PDT) From: Jeff Layton To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org Subject: [PATCH] nfsd: don't halt scanning the DRC LRU list when there's an RC_INPROG entry Date: Thu, 5 Jun 2014 09:45:00 -0400 Message-Id: <1401975900-13398-1-git-send-email-jlayton@primarydata.com> X-Mailer: git-send-email 1.9.3 Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, 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 Currently, the DRC cache pruner will stop scanning the list when it hits an entry that is RC_INPROG. It's possible however for a call to take a *very* long time. In that case, we don't want it to block other entries from being pruned if they are expired or we need to trim the cache to get back under the limit. Fix the DRC cache pruner to just ignore RC_INPROG entries. Signed-off-by: Jeff Layton --- fs/nfsd/nfscache.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index f8f060ffbf4f..6040da8830ff 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c @@ -224,13 +224,6 @@ hash_refile(struct svc_cacherep *rp) hlist_add_head(&rp->c_hash, cache_hash + hash_32(rp->c_xid, maskbits)); } -static inline bool -nfsd_cache_entry_expired(struct svc_cacherep *rp) -{ - return rp->c_state != RC_INPROG && - time_after(jiffies, rp->c_timestamp + RC_EXPIRE); -} - /* * Walk the LRU list and prune off entries that are older than RC_EXPIRE. * Also prune the oldest ones when the total exceeds the max number of entries. @@ -242,8 +235,14 @@ prune_cache_entries(void) long freed = 0; list_for_each_entry_safe(rp, tmp, &lru_head, c_lru) { - if (!nfsd_cache_entry_expired(rp) && - num_drc_entries <= max_drc_entries) + /* + * Don't free entries attached to calls that are still + * in-progress, but do keep scanning the list. + */ + if (rp->c_state == RC_INPROG) + continue; + if (num_drc_entries <= max_drc_entries && + time_before(jiffies, rp->c_timestamp + RC_EXPIRE)) break; nfsd_reply_cache_free_locked(rp); freed++;