From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757646AbaGPBtm (ORCPT ); Tue, 15 Jul 2014 21:49:42 -0400 Received: from mail-yk0-f179.google.com ([209.85.160.179]:63642 "EHLO mail-yk0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751593AbaGPBti (ORCPT ); Tue, 15 Jul 2014 21:49:38 -0400 From: Pranith Kumar To: "Paul E. McKenney" , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , linux-kernel@vger.kernel.org (open list:READ-COPY UPDATE...) Subject: [PATCH 1/1] rcu: Remove redundant checks for rcu_scheduler_fully_active Date: Tue, 15 Jul 2014 21:50:02 -0400 Message-Id: <1405475402-7181-1-git-send-email-bobby.prani@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org rcu_scheduler_fully_active is set to true early in the boot process. rcu_prepare_kthreads() is called in two locations. Once after setting the above flag and the other while hotplugging a CPU from rcu_cpu_notify(). CPU hotplug is enabled much later by which time the above flag is already set. Hence checking for this flag is redundant in this function. The checks in rcu_spawn_one_boost_kthread() and rcu_spawn_all_nocb_kthreads() are similarly redundant. This commit removes the redundant checks for this flag from the above locations. Signed-off-by: Pranith Kumar --- kernel/rcu/tree_plugin.h | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 17ccb62..a2113f6 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -1341,7 +1341,7 @@ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, if (&rcu_preempt_state != rsp) return 0; - if (!rcu_scheduler_fully_active || rnp->qsmaskinit == 0) + if (rnp->qsmaskinit == 0) return 0; rsp->boost = 1; @@ -1489,8 +1489,7 @@ static void rcu_prepare_kthreads(int cpu) struct rcu_node *rnp = rdp->mynode; /* Fire up the incoming CPU's kthread and leaf rcu_node kthread. */ - if (rcu_scheduler_fully_active) - (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp); + (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp); } #else /* #ifdef CONFIG_RCU_BOOST */ @@ -2509,9 +2508,8 @@ static void rcu_spawn_all_nocb_kthreads(int cpu) { struct rcu_state *rsp; - if (rcu_scheduler_fully_active) - for_each_rcu_flavor(rsp) - rcu_spawn_one_nocb_kthread(rsp, cpu); + for_each_rcu_flavor(rsp) + rcu_spawn_one_nocb_kthread(rsp, cpu); } /* -- 1.9.1