From patchwork Thu May 16 07:19:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herbert Xu X-Patchwork-Id: 1100393 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=gondor.apana.org.au Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 454N9B40dFz9sB8 for ; Thu, 16 May 2019 17:19:58 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726702AbfEPHT5 (ORCPT ); Thu, 16 May 2019 03:19:57 -0400 Received: from orcrist.hmeau.com ([5.180.42.13]:44074 "EHLO deadmen.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726486AbfEPHTz (ORCPT ); Thu, 16 May 2019 03:19:55 -0400 Received: from gondobar.mordor.me.apana.org.au ([192.168.128.4] helo=gondobar) by deadmen.hmeau.com with esmtps (Exim 4.89 #2 (Debian)) id 1hRAg8-0004Pa-Bo; Thu, 16 May 2019 15:19:48 +0800 Received: from herbert by gondobar with local (Exim 4.89) (envelope-from ) id 1hRAg8-0004Fy-0O; Thu, 16 May 2019 15:19:48 +0800 Subject: [PATCH 2/2] rhashtable: Fix cmpxchg RCU warnings References: <20190516051622.b4x6hlkuevof4jzr@gondor.apana.org.au> To: Jakub Kicinski , davem@davemloft.net, tgraf@suug.ch, netdev@vger.kernel.org, oss-drivers@netronome.com, neilb@suse.com, Simon Horman Message-Id: From: Herbert Xu Date: Thu, 16 May 2019 15:19:48 +0800 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As cmpxchg is a non-RCU mechanism it will cause sparse warnings when we use it for RCU. This patch adds explicit casts to silence those warnings. This should probably be moved to RCU itself in future. Signed-off-by: Herbert Xu --- lib/rhashtable.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 7708699a5b96..935ec80f213f 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -131,7 +131,7 @@ static union nested_table *nested_table_alloc(struct rhashtable *ht, INIT_RHT_NULLS_HEAD(ntbl[i].bucket); } - if (cmpxchg(prev, NULL, ntbl) == NULL) + if (cmpxchg((union nested_table **)prev, NULL, ntbl) == NULL) return ntbl; /* Raced with another thread. */ kfree(ntbl); @@ -296,7 +296,8 @@ static int rhashtable_rehash_attach(struct rhashtable *ht, * rcu_assign_pointer(). */ - if (cmpxchg(&old_tbl->future_tbl, NULL, new_tbl) != NULL) + if (cmpxchg((struct bucket_table **)&old_tbl->future_tbl, NULL, + new_tbl) != NULL) return -EEXIST; return 0;