Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752331Ab2K2JHB (ORCPT ); Thu, 29 Nov 2012 04:07:01 -0500 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:48864 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751553Ab2K2JG5 (ORCPT ); Thu, 29 Nov 2012 04:06:57 -0500 Message-ID: <1354179992.2499.35.camel@ThinkPad-T5421.cn.ibm.com> Subject: Re: [PATCH] context_tracking: New context tracking susbsystem From: Li Zhong To: Frederic Weisbecker Cc: "Paul E. McKenney" , LKML , Andrew Morton , "H. Peter Anvin" , Ingo Molnar , Peter Zijlstra , Steven Rostedt , Thomas Gleixner , Gilad.Ben-Yossef.gilad@benyossef.com Date: Thu, 29 Nov 2012 17:06:32 +0800 In-Reply-To: <1354041205-6989-1-git-send-email-fweisbec@gmail.com> References: <1354041205-6989-1-git-send-email-fweisbec@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 x-cbid: 12112909-8256-0000-0000-0000053A9E1D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1788 Lines: 54 On Tue, 2012-11-27 at 19:33 +0100, Frederic Weisbecker wrote: [....] > - > - WARN_ON_ONCE(!current->mm); > - > - local_irq_save(flags); > - rdtp = &__get_cpu_var(rcu_dynticks); > - if (!rdtp->ignore_user_qs && !rdtp->in_user) { > - rdtp->in_user = true; > - rcu_eqs_enter(true); > - } It seems to me that ignore_user_qs and in_user defined in struct rcu_dynticks are no longer needed? If so, then maybe we could remove them, code below: ========== diff --git a/kernel/rcutree.c b/kernel/rcutree.c index e441b77..b8fae5d 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -2719,9 +2719,6 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) rdp->dynticks = &per_cpu(rcu_dynticks, cpu); WARN_ON_ONCE(rdp->dynticks->dynticks_nesting != DYNTICK_TASK_EXIT_IDLE); WARN_ON_ONCE(atomic_read(&rdp->dynticks->dynticks) != 1); -#ifdef CONFIG_RCU_USER_QS - WARN_ON_ONCE(rdp->dynticks->in_user); -#endif rdp->cpu = cpu; rdp->rsp = rsp; rcu_boot_init_nocb_percpu_data(rdp); diff --git a/kernel/rcutree.h b/kernel/rcutree.h index 4b69291..6f21f2e 100644 --- a/kernel/rcutree.h +++ b/kernel/rcutree.h @@ -102,10 +102,6 @@ struct rcu_dynticks { /* idle-period nonlazy_posted snapshot. */ int tick_nohz_enabled_snap; /* Previously seen value from sysfs. */ #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ -#ifdef CONFIG_RCU_USER_QS - bool ignore_user_qs; /* Treat userspace as extended QS or not */ - bool in_user; /* Is the CPU in userland from RCU POV? */ -#endif }; /* RCU's kthread states for tracing. */ -- 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/