From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755266AbbAGRcu (ORCPT ); Wed, 7 Jan 2015 12:32:50 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:56850 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753668AbbAGRcq (ORCPT ); Wed, 7 Jan 2015 12:32:46 -0500 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 13/14] rcu: Don't scan root rcu_node structure for stalled tasks Date: Wed, 7 Jan 2015 09:32:32 -0800 Message-Id: <1420651953-2651-13-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1420651953-2651-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20150107173215.GA897@linux.vnet.ibm.com> <1420651953-2651-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15010717-0029-0000-0000-00000703EF13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" Now that blocked tasks are no longer migrated to the root rcu_node structure, there is no need to scan the root rcu_node structure for blocked tasks stalling the current grace period. This commit therefore removes this scan. Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 24d3c67f7be7..4ed2c2842103 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1107,15 +1107,6 @@ static void print_other_cpu_stall(struct rcu_state *rsp) raw_spin_unlock_irqrestore(&rnp->lock, flags); } - /* - * Now rat on any tasks that got kicked up to the root rcu_node - * due to CPU offlining. - */ - rnp = rcu_get_root(rsp); - raw_spin_lock_irqsave(&rnp->lock, flags); - ndetected += rcu_print_task_stall(rnp); - raw_spin_unlock_irqrestore(&rnp->lock, flags); - print_cpu_stall_info_end(); for_each_possible_cpu(cpu) totqlen += per_cpu_ptr(rsp->rda, cpu)->qlen; -- 1.8.1.5