From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Kacur Subject: [PATCH RT] rcu: Fix build break Date: Fri, 13 Apr 2012 12:54:21 +0200 Message-ID: <1334314461-8937-1-git-send-email-jkacur@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: lkml , rt-users , John Kacur To: Thomas Gleixner , Paul McKenney Return-path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:64125 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751074Ab2DMKy0 (ORCPT ); Fri, 13 Apr 2012 06:54:26 -0400 Sender: linux-rt-users-owner@vger.kernel.org List-ID: A build break can occur with the following config options enabled CONFIG_PREEMPT_RT_FULL CONFIG_RCU_FAST_NO_HZ CONFIG_RCU_CPU_STALL_INFO This occurs because symbols in print_cpu_stall_fast_no_hz() such as rcu_idle_gp_timer are not accessible with CONFIG_PREEMPT_RT_FULL and results in the following type of build errors: kernel/rcutree_plugin.h: In function =E2=80=98print_cpu_stall_fast_no_h= z=E2=80=99: kernel/rcutree_plugin.h:2195: error: =E2=80=98rcu_idle_gp_timer=E2=80=99= undeclared (first use in this function) This patch fixes the build break by limiting the to the function rcu_needs_cpu() instead of to the entire !defined(CONFIG_RCU_FAST_NO_NZ) section as was intended in the original rcu: Make ksoftirqd do RCU quiescent st= ates patch. Signed-off-by: John Kacur --- kernel/rcutree_plugin.h | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 14acafc..2844d7d 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -1914,6 +1914,9 @@ int rcu_needs_cpu(int cpu) { return rcu_cpu_has_callbacks(cpu); } +#endif /* !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT= _FULL) */ + +#if !defined(CONFIG_RCU_FAST_NO_HZ) =20 /* * Because we do not have RCU_FAST_NO_HZ, don't bother initializing fo= r it. @@ -1984,6 +1987,7 @@ static DEFINE_PER_CPU(struct hrtimer, rcu_idle_gp= _timer); static ktime_t rcu_idle_gp_wait; /* If some non-lazy callbacks. */ static ktime_t rcu_idle_lazy_gp_wait; /* If only lazy callbacks. */ =20 +#ifndef CONFIG_PREEMPT_RT_FULL /* * Allow the CPU to enter dyntick-idle mode if either: (1) There are n= o * callbacks on this CPU, (2) this CPU has not yet attempted to enter @@ -2001,6 +2005,7 @@ int rcu_needs_cpu(int cpu) /* Otherwise, RCU needs the CPU only if it recently tried and failed.= */ return per_cpu(rcu_dyntick_holdoff, cpu) =3D=3D jiffies; } +#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */ =20 /* * Does the specified flavor of RCU have non-lazy callbacks pending on --=20 1.7.2.3 -- To unsubscribe from this list: send the line "unsubscribe linux-rt-user= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html