Return-Path: Received: from mail-it1-f193.google.com ([209.85.166.193]:38751 "EHLO mail-it1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729489AbeJAVUf (ORCPT ); Mon, 1 Oct 2018 17:20:35 -0400 Received: by mail-it1-f193.google.com with SMTP id i76-v6so6171241ita.3 for ; Mon, 01 Oct 2018 07:42:27 -0700 (PDT) From: Trond Myklebust To: "J . Bruce Fields" Cc: linux-nfs@vger.kernel.org Subject: [PATCH 08/15] NFS: Lockless DNS lookups Date: Mon, 1 Oct 2018 10:41:50 -0400 Message-Id: <20181001144157.3515-9-trond.myklebust@hammerspace.com> In-Reply-To: <20181001144157.3515-8-trond.myklebust@hammerspace.com> References: <20181001144157.3515-1-trond.myklebust@hammerspace.com> <20181001144157.3515-2-trond.myklebust@hammerspace.com> <20181001144157.3515-3-trond.myklebust@hammerspace.com> <20181001144157.3515-4-trond.myklebust@hammerspace.com> <20181001144157.3515-5-trond.myklebust@hammerspace.com> <20181001144157.3515-6-trond.myklebust@hammerspace.com> <20181001144157.3515-7-trond.myklebust@hammerspace.com> <20181001144157.3515-8-trond.myklebust@hammerspace.com> MIME-Version: 1.0 Sender: linux-nfs-owner@vger.kernel.org List-ID: Enable RCU protected lookup in the legacy DNS resolver. Signed-off-by: Trond Myklebust --- fs/nfs/dns_resolve.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/fs/nfs/dns_resolve.c b/fs/nfs/dns_resolve.c index 060c658eab66..e93a5dc07c8c 100644 --- a/fs/nfs/dns_resolve.c +++ b/fs/nfs/dns_resolve.c @@ -65,6 +65,7 @@ struct nfs_dns_ent { struct sockaddr_storage addr; size_t addrlen; + struct rcu_head rcu_head; }; @@ -101,15 +102,23 @@ static void nfs_dns_ent_init(struct cache_head *cnew, } } -static void nfs_dns_ent_put(struct kref *ref) +static void nfs_dns_ent_free_rcu(struct rcu_head *head) { struct nfs_dns_ent *item; - item = container_of(ref, struct nfs_dns_ent, h.ref); + item = container_of(head, struct nfs_dns_ent, rcu_head); kfree(item->hostname); kfree(item); } +static void nfs_dns_ent_put(struct kref *ref) +{ + struct nfs_dns_ent *item; + + item = container_of(ref, struct nfs_dns_ent, h.ref); + call_rcu(item, nfs_dns_ent_free_rcu); +} + static struct cache_head *nfs_dns_ent_alloc(void) { struct nfs_dns_ent *item = kmalloc(sizeof(*item), GFP_KERNEL); @@ -195,7 +204,7 @@ static struct nfs_dns_ent *nfs_dns_lookup(struct cache_detail *cd, { struct cache_head *ch; - ch = sunrpc_cache_lookup(cd, + ch = sunrpc_cache_lookup_rcu(cd, &key->h, nfs_dns_hash(key)); if (!ch) -- 2.17.1