Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753823AbaLEXDn (ORCPT ); Fri, 5 Dec 2014 18:03:43 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:54457 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753413AbaLEW4X (ORCPT ); Fri, 5 Dec 2014 17:56:23 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Layton , "J. Bruce Fields" , Joseph Salisbury Subject: [PATCH 3.14 63/73] nfsd: dont halt scanning the DRC LRU list when theres an RC_INPROG entry Date: Fri, 5 Dec 2014 14:45:09 -0800 Message-Id: <20141205224435.816947395@linuxfoundation.org> X-Mailer: git-send-email 2.1.3 In-Reply-To: <20141205224433.921659956@linuxfoundation.org> References: <20141205224433.921659956@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 1b19453d1c6abcfa7c312ba6c9f11a277568fc94 upstream. 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 Signed-off-by: J. Bruce Fields Cc: Joseph Salisbury Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfscache.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) --- 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++; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/