Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934217AbbEMAh6 (ORCPT ); Tue, 12 May 2015 20:37:58 -0400 Received: from mail-wg0-f54.google.com ([74.125.82.54]:33835 "EHLO mail-wg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934129AbbEMAhz (ORCPT ); Tue, 12 May 2015 20:37:55 -0400 Date: Wed, 13 May 2015 02:37:52 +0200 From: Frederic Weisbecker To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, 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, oleg@redhat.com, bobby.prani@gmail.com Subject: Re: [PATCH tip/core/rcu 15/24] rcu: Directly drive RCU_USER_QS from Kconfig Message-ID: <20150513003750.GA1806@lerouge> References: <20150512223034.GA1396@linux.vnet.ibm.com> <1431469854-3826-1-git-send-email-paulmck@linux.vnet.ibm.com> <1431469854-3826-15-git-send-email-paulmck@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1431469854-3826-15-git-send-email-paulmck@linux.vnet.ibm.com> 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: 2026 Lines: 56 On Tue, May 12, 2015 at 03:30:45PM -0700, Paul E. McKenney wrote: > From: "Paul E. McKenney" > > Currently, Kconfig will ask the user whether RCU_USER_QS should be set. > This is silly because Kconfig already has all the information that it > needs to set this parameter. This commit therefore directly drives > the value of RCU_USER_QS via NO_HZ_FULL's "select" statement. > > Reported-by: Ingo Molnar > Signed-off-by: Paul E. McKenney > Cc: Frederic Weisbecker ACK. And we should remove it completely and use NO_HZ_FULL instead. There won't seem to be more users. > Reviewed-by: Pranith Kumar > --- > init/Kconfig | 10 +--------- > 1 file changed, 1 insertion(+), 9 deletions(-) > > diff --git a/init/Kconfig b/init/Kconfig > index 73db30a76afa..927210810189 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -529,9 +529,7 @@ config CONTEXT_TRACKING > bool > > config RCU_USER_QS > - bool "Consider userspace as in RCU extended quiescent state" > - depends on HAVE_CONTEXT_TRACKING && SMP > - select CONTEXT_TRACKING > + bool > help > This option sets hooks on kernel / userspace boundaries and > puts RCU in extended quiescent state when the CPU runs in > @@ -539,12 +537,6 @@ config RCU_USER_QS > excluded from the global RCU state machine and thus doesn't > try to keep the timer tick on for RCU. > > - Unless you want to hack and help the development of the full > - dynticks mode, you shouldn't enable this option. It also > - adds unnecessary overhead. > - > - If unsure say N > - > config CONTEXT_TRACKING_FORCE > bool "Force context tracking" > depends on CONTEXT_TRACKING > -- > 1.8.1.5 > -- 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/