Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752174AbbEFMse (ORCPT ); Wed, 6 May 2015 08:48:34 -0400 Received: from mail-wi0-f195.google.com ([209.85.212.195]:35685 "EHLO mail-wi0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750940AbbEFMsc (ORCPT ); Wed, 6 May 2015 08:48:32 -0400 From: Ingo Molnar X-Google-Original-From: Ingo Molnar Date: Wed, 6 May 2015 14:48:29 +0200 To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, "Paul E. McKenney" , Peter Zijlstra , Andrew Morton Subject: [GIT PULL] RCU fix Message-ID: <20150506124828.GA19391@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2868 Lines: 76 Linus, Please pull the latest core-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core-urgent-for-linus # HEAD: cb0f3f320d64831afb39940863c5927d6af25514 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent An RCU Kconfig fix that eliminates an annoying interactive kconfig question for CONFIG_RCU_TORTURE_TEST_SLOW_INIT. Thanks, Ingo ------------------> Paul E. McKenney (1): rcu: Control grace-period delays directly from value kernel/rcu/tree.c | 16 +++++++++------- lib/Kconfig.debug | 1 + 2 files changed, 10 insertions(+), 7 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 233165da782f..8cf7304b2867 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -162,11 +162,14 @@ static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); static int kthread_prio = CONFIG_RCU_KTHREAD_PRIO; module_param(kthread_prio, int, 0644); -/* Delay in jiffies for grace-period initialization delays. */ -static int gp_init_delay = IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_INIT) - ? CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY - : 0; +/* Delay in jiffies for grace-period initialization delays, debug only. */ +#ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT +static int gp_init_delay = CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY; module_param(gp_init_delay, int, 0644); +#else /* #ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT */ +static const int gp_init_delay; +#endif /* #else #ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT */ +#define PER_RCU_NODE_PERIOD 10 /* Number of grace periods between delays. */ /* * Track the rcutorture test sequence number and the update version @@ -1843,9 +1846,8 @@ static int rcu_gp_init(struct rcu_state *rsp) raw_spin_unlock_irq(&rnp->lock); cond_resched_rcu_qs(); ACCESS_ONCE(rsp->gp_activity) = jiffies; - if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_INIT) && - gp_init_delay > 0 && - !(rsp->gpnum % (rcu_num_nodes * 10))) + if (gp_init_delay > 0 && + !(rsp->gpnum % (rcu_num_nodes * PER_RCU_NODE_PERIOD))) schedule_timeout_uninterruptible(gp_init_delay); } diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 93967e634a1e..7815ddd5ae56 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1281,6 +1281,7 @@ config RCU_TORTURE_TEST_SLOW_INIT_DELAY int "How much to slow down RCU grace-period initialization" range 0 5 default 3 + depends on RCU_TORTURE_TEST_SLOW_INIT help This option specifies the number of jiffies to wait between each rcu_node structure initialization. -- 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/