Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753728AbaF3MW1 (ORCPT ); Mon, 30 Jun 2014 08:22:27 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:51921 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752909AbaF3LxY (ORCPT ); Mon, 30 Jun 2014 07:53:24 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jeff Layton , "J. Bruce Fields" , Jiri Slaby Subject: [PATCH 3.12 049/181] nfsd: don't halt scanning the DRC LRU list when there's an RC_INPROG entry Date: Mon, 30 Jun 2014 13:51:10 +0200 Message-Id: <26e4087753f583b4b4db74937aa74beab09167dd.1404128998.git.jslaby@suse.cz> X-Mailer: git-send-email 2.0.0 In-Reply-To: <61844d8e25eb8899b0836afa9796fa239db80f1f.1404128997.git.jslaby@suse.cz> References: <61844d8e25eb8899b0836afa9796fa239db80f1f.1404128997.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jeff Layton 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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 Signed-off-by: Jiri Slaby --- 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++; -- 2.0.0 -- 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/