Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754843Ab3EPBJ7 (ORCPT ); Wed, 15 May 2013 21:09:59 -0400 Received: from g1t0026.austin.hp.com ([15.216.28.33]:33181 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754008Ab3EPBIQ (ORCPT ); Wed, 15 May 2013 21:08:16 -0400 From: Davidlohr Bueso To: akpm@linux-foundation.org Cc: torvalds@linux-foundation.org, riel@redhat.com, linux-kernel@vger.kernel.org, Davidlohr Bueso Subject: [PATCH 07/11] ipc,msg: introduce lockless functions to obtain the ipc object Date: Wed, 15 May 2013 18:08:06 -0700 Message-Id: <1368666490-29055-8-git-send-email-davidlohr.bueso@hp.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1368666490-29055-1-git-send-email-davidlohr.bueso@hp.com> References: <1368666490-29055-1-git-send-email-davidlohr.bueso@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1531 Lines: 50 Add msq_obtain_object() and msq_obtain_object_check(), which will allow us to get the ipc object without acquiring the lock. Just as with semaphores, these functions are basically wrappers around ipc_obtain_object*(). Signed-off-by: Davidlohr Bueso --- ipc/msg.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/ipc/msg.c b/ipc/msg.c index 20361b5..9ff295b 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -166,6 +166,27 @@ static inline struct msg_queue *msg_lock_check(struct ipc_namespace *ns, return container_of(ipcp, struct msg_queue, q_perm); } +static inline struct msg_queue *msq_obtain_object(struct ipc_namespace *ns, int id) +{ + struct kern_ipc_perm *ipcp = ipc_obtain_object(&msg_ids(ns), id); + + if (IS_ERR(ipcp)) + return ERR_CAST(ipcp); + + return container_of(ipcp, struct msg_queue, q_perm); +} + +static inline struct msg_queue *msq_obtain_object_check(struct ipc_namespace *ns, + int id) +{ + struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&msg_ids(ns), id); + + if (IS_ERR(ipcp)) + return ERR_CAST(ipcp); + + return container_of(ipcp, struct msg_queue, q_perm); +} + static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s) { ipc_rmid(&msg_ids(ns), &s->q_perm); -- 1.7.11.7 -- 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/