Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933293AbbDUT5I (ORCPT ); Tue, 21 Apr 2015 15:57:08 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:43329 "EHLO e33.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933107AbbDUT4E (ORCPT ); Tue, 21 Apr 2015 15:56:04 -0400 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 12/12] rcu: Make RCU able to tolerate undefined CONFIG_RCU_KTHREAD_PRIO Date: Tue, 21 Apr 2015 12:55:53 -0700 Message-Id: <1429646153-20677-12-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1429646153-20677-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20150421195529.GA17864@linux.vnet.ibm.com> <1429646153-20677-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15042119-0009-0000-0000-00000A4456A3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2130 Lines: 54 From: "Paul E. McKenney" This commit updates the initialization of the kthread_prio boot parameter so that RCU will build even when CONFIG_RCU_KTHREAD_PRIO is undefined. The kthread_prio boot parameter is set to CONFIG_RCU_KTHREAD_PRIO if that is defined, otherwise to 1 if CONFIG_RCU_BOOST is defined and to zero otherwise. This commit then makes CONFIG_RCU_KTHREAD_PRIO depend on CONFIG_RCU_EXPERT, so that Kconfig users won't be asked about CONFIG_RCU_KTHREAD_PRIO unless they want to be. Reported-by: Linus Torvalds Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney --- init/Kconfig | 1 + kernel/rcu/tree.c | 4 ++++ 2 files changed, 5 insertions(+) diff --git a/init/Kconfig b/init/Kconfig index 17285e8e555d..9d6e9ffb47f1 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -671,6 +671,7 @@ config RCU_KTHREAD_PRIO range 0 99 if !RCU_BOOST default 1 if RCU_BOOST default 0 if !RCU_BOOST + depends on RCU_EXPERT help This option specifies the SCHED_FIFO priority value that will be assigned to the rcuc/n and rcub/n threads and is also the value diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0a6d46df2194..b432f2ea6bba 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -161,7 +161,11 @@ static void invoke_rcu_core(void); static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); /* rcuc/rcub kthread realtime priority */ +#ifdef CONFIG_RCU_KTHREAD_PRIO static int kthread_prio = CONFIG_RCU_KTHREAD_PRIO; +#else /* #ifdef CONFIG_RCU_KTHREAD_PRIO */ +static int kthread_prio = IS_ENABLED(CONFIG_RCU_BOOST) ? 1 : 0; +#endif /* #else #ifdef CONFIG_RCU_KTHREAD_PRIO */ module_param(kthread_prio, int, 0644); /* Delay in jiffies for grace-period initialization delays, debug only. */ -- 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/