From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757125Ab3ETOjD (ORCPT ); Mon, 20 May 2013 10:39:03 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:42020 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757015Ab3ETOi7 (ORCPT ); Mon, 20 May 2013 10:38:59 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, edumazet@google.com, darren@dvhart.com, fweisbec@gmail.com, sbw@mit.edu, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 8/8] rcu: Move redundant call to note_gp_changes() into called function Date: Mon, 20 May 2013 07:38:15 -0700 Message-Id: <1369060695-29679-8-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1369060695-29679-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20130520143739.GA29365@linux.vnet.ibm.com> <1369060695-29679-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13052014-5806-0000-0000-000021399369 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" The __rcu_process_callbacks() invokes note_gp_changes() immediately before invoking rcu_check_quiescent_state(), which conditionally invokes that same function. This commit therefore eliminates the call to note_gp_changes() in __rcu_process_callbacks() in favor of making unconditional to call from rcu_check_quiescent_state() to note_gp_changes(). Signed-off-by: Paul E. McKenney Reviewed-by: Josh Triplett --- kernel/rcutree.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/kernel/rcutree.c b/kernel/rcutree.c index 14fa927..34db855 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -1704,11 +1704,8 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) static void rcu_check_quiescent_state(struct rcu_state *rsp, struct rcu_data *rdp) { - /* If there is now a new grace period, record and return. */ - if (rdp->gpnum != rsp->gpnum) { - note_gp_changes(rsp, rdp); - return; - } + /* Check for grace-period ends and beginnings. */ + note_gp_changes(rsp, rdp); /* * Does this CPU still need to do its part for current grace period? @@ -2172,9 +2169,6 @@ __rcu_process_callbacks(struct rcu_state *rsp) WARN_ON_ONCE(rdp->beenonline == 0); - /* Handle the end of a grace period that some other CPU ended. */ - note_gp_changes(rsp, rdp); - /* Update RCU state based on any recent quiescent states. */ rcu_check_quiescent_state(rsp, rdp); -- 1.8.1.5