Re: [PATCH -tip 0/2] Temporary RCU fixes for notrace and hotplug CPU

Paul E. McKenney
2009-08-25T15:40:28Z

On Tue, Aug 25, 2009 at 08:55:01AM +0200, Ingo Molnar wrote:
>
> FYI, -tip testing found a new build warning on SH caused by the RCU
> tree (i suspect this warning triggers on other architectures as
> well):
>
> /home/mingo/tip/kernel/rcutree.c:88: warning: '__rcu_offline_cpu'
> declared 'static' but never defined

<red face>

> it's harmless, but since we are generally trying to fix all warnings
> and gravitate towards more and more -Werror subsystems, it would be
> nice to fix this.

Indeed, and I have updated my build-output-check script to alert me to
warning messages from my multiple-configuration test runs. Please see
below for patch.

Thanx, Paul

------------------------------------------------------------------------

Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---

rcutree.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 000b076..fee6316 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -84,7 +84,9 @@ extern long rcu_batches_completed_sched(void);
static void cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp,
struct rcu_node *rnp, unsigned long flags);
static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags);
+#ifdef CONFIG_HOTPLUG_CPU
static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
static void __rcu_process_callbacks(struct rcu_state *rsp,
struct rcu_data *rdp);
static void __call_rcu(struct rcu_head *head,