[PATCH] kernel: rcu: tree: Remove useless rcu_data_p when !PREEMPT_RCU

[PATCH] kernel: rcu: tree: Remove useless rcu_data_p when !PREEMPT_RCU

[chengang]

From: Chen Gang <chengang@emindsoft.com.cn>

The related warning from gcc 6.0:

  In file included from kernel/rcu/tree.c:4630:0:
  kernel/rcu/tree_plugin.h:810:40: warning: ‘rcu_data_p’ defined but not used [-Wunused-const-variable]
   static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
                                          ^~~~~~~~~~

Also remove always redundant rcu_data_p in tree.c.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
---
 kernel/rcu/tree.c        | 1 -
 kernel/rcu/tree_plugin.h | 1 -
 2 files changed, 2 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 3a8856f..ed85d66 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -108,7 +108,6 @@ RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
 RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh);
 
 static struct rcu_state *const rcu_state_p;
-static struct rcu_data __percpu *const rcu_data_p;
 LIST_HEAD(rcu_struct_flavors);
 
 /* Dump rcu_node combining tree at boot to verify correct setup. */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 9467a8b..e6b88ad 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -807,7 +807,6 @@ void exit_rcu(void)
 #else /* #ifdef CONFIG_PREEMPT_RCU */
 
 static struct rcu_state *const rcu_state_p = &rcu_sched_state;
-static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
 
 /*
  * Tell them what RCU they are running.
-- 
1.9.3

Re: [PATCH] kernel: rcu: tree: Remove useless rcu_data_p when !PREEMPT_RCU

[Paul E. McKenney]

On Sat, Dec 26, 2015 at 09:41:44PM +0800, chengang@emindsoft.com.cn wrote:
> From: Chen Gang <chengang@emindsoft.com.cn>
> 
> The related warning from gcc 6.0:
> 
>   In file included from kernel/rcu/tree.c:4630:0:
>   kernel/rcu/tree_plugin.h:810:40: warning: ‘rcu_data_p’ defined but not used [-Wunused-const-variable]
>    static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
>                                           ^~~~~~~~~~
> 
> Also remove always redundant rcu_data_p in tree.c.
> 
> Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>

Queued for review and testing, thank you!

							Thanx, Paul

> ---
>  kernel/rcu/tree.c        | 1 -
>  kernel/rcu/tree_plugin.h | 1 -
>  2 files changed, 2 deletions(-)
> 
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index 3a8856f..ed85d66 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -108,7 +108,6 @@ RCU_STATE_INITIALIZER(rcu_sched, 's', call_rcu_sched);
>  RCU_STATE_INITIALIZER(rcu_bh, 'b', call_rcu_bh);
> 
>  static struct rcu_state *const rcu_state_p;
> -static struct rcu_data __percpu *const rcu_data_p;
>  LIST_HEAD(rcu_struct_flavors);
> 
>  /* Dump rcu_node combining tree at boot to verify correct setup. */
> diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> index 9467a8b..e6b88ad 100644
> --- a/kernel/rcu/tree_plugin.h
> +++ b/kernel/rcu/tree_plugin.h
> @@ -807,7 +807,6 @@ void exit_rcu(void)
>  #else /* #ifdef CONFIG_PREEMPT_RCU */
> 
>  static struct rcu_state *const rcu_state_p = &rcu_sched_state;
> -static struct rcu_data __percpu *const rcu_data_p = &rcu_sched_data;
> 
>  /*
>   * Tell them what RCU they are running.
> -- 
> 1.9.3
>