From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757541AbcCDENL (ORCPT ); Thu, 3 Mar 2016 23:13:11 -0500 Received: from ozlabs.org ([103.22.144.67]:33580 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756704AbcCDENJ (ORCPT ); Thu, 3 Mar 2016 23:13:09 -0500 Date: Fri, 4 Mar 2016 15:13:06 +1100 From: Stephen Rothwell To: "Paul E. McKenney" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra Cc: linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, Boqun Feng Subject: linux-next: manual merge of the rcu tree with the tip tree Message-ID: <20160304151306.05e3bb36@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Paul, Today's linux-next merge of the rcu tree got a conflict in: kernel/rcu/tree.c between commit: 27d50c7eeb0f ("rcu: Make CPU_DYING_IDLE an explicit call") from the tip tree and commit: 67c583a7de34 ("RCU: Privatize rcu_node::lock") from the rcu tree. I fixed it up (see below) and can carry the fix as necessary (no action is required). -- Cheers, Stephen Rothwell diff --cc kernel/rcu/tree.c index 0bbc1497a0e4,55cea189783f..000000000000 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@@ -4227,43 -4246,6 +4224,43 @@@ static void rcu_prepare_cpu(int cpu rcu_init_percpu_data(cpu, rsp); } +#ifdef CONFIG_HOTPLUG_CPU +/* + * The CPU is exiting the idle loop into the arch_cpu_idle_dead() + * function. We now remove it from the rcu_node tree's ->qsmaskinit + * bit masks. + */ +static void rcu_cleanup_dying_idle_cpu(int cpu, struct rcu_state *rsp) +{ + unsigned long flags; + unsigned long mask; + struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu); + struct rcu_node *rnp = rdp->mynode; /* Outgoing CPU's rdp & rnp. */ + + if (!IS_ENABLED(CONFIG_HOTPLUG_CPU)) + return; + + /* Remove outgoing CPU from mask in the leaf rcu_node structure. */ + mask = rdp->grpmask; + raw_spin_lock_irqsave_rcu_node(rnp, flags); /* Enforce GP memory-order guarantee. */ + rnp->qsmaskinitnext &= ~mask; - raw_spin_unlock_irqrestore(&rnp->lock, flags); ++ raw_spin_unlock_irqrestore_rcu_node(rnp, flags); +} + +void rcu_report_dead(unsigned int cpu) +{ + struct rcu_state *rsp; + + /* QS for any half-done expedited RCU-sched GP. */ + preempt_disable(); + rcu_report_exp_rdp(&rcu_sched_state, + this_cpu_ptr(rcu_sched_state.rda), true); + preempt_enable(); + for_each_rcu_flavor(rsp) + rcu_cleanup_dying_idle_cpu(cpu, rsp); +} +#endif + /* * Handle CPU online/offline notification events. */