[PATCH v2] rcu: Remove rcu_switch()

[PATCH v2] rcu: Remove rcu_switch()

[Frederic Weisbecker]

It's only there to call rcu_user_hooks_switch(). Let's
just call rcu_user_hooks_switch() directly, we don't need this
function in the middle.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
 arch/um/drivers/mconsole_kern.c |    2 +-
 include/linux/rcupdate.h        |    2 ++
 include/linux/sched.h           |    8 --------
 kernel/sched/core.c             |    2 +-
 4 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index c17de0d..0b989af 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -705,7 +705,7 @@ static void stack_proc(void *arg)
 	struct task_struct *from = current, *to = arg;
 
 	to->thread.saved_task = from;
-	rcu_switch(from, to);
+	rcu_user_hooks_switch(from, to);
 	switch_to(from, to, from);
 }
 
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index 7c968e4..5d009de 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -204,6 +204,8 @@ static inline void rcu_user_enter(void) { }
 static inline void rcu_user_exit(void) { }
 static inline void rcu_user_enter_after_irq(void) { }
 static inline void rcu_user_exit_after_irq(void) { }
+static inline void rcu_user_hooks_switch(struct task_struct *prev,
+					 struct task_struct *next) { }
 #endif /* CONFIG_RCU_USER_QS */
 
 extern void exit_rcu(void);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index fade317..c300c7c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1887,14 +1887,6 @@ static inline void rcu_copy_process(struct task_struct *p)
 
 #endif
 
-static inline void rcu_switch(struct task_struct *prev,
-			      struct task_struct *next)
-{
-#ifdef CONFIG_RCU_USER_QS
-	rcu_user_hooks_switch(prev, next);
-#endif
-}
-
 static inline void tsk_restore_flags(struct task_struct *task,
 				unsigned long orig_flags, unsigned long flags)
 {
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index dd036fe..b53a485 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2081,7 +2081,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
 #endif
 
 	/* Here we just switch the register state and the stack. */
-	rcu_switch(prev, next);
+	rcu_user_hooks_switch(prev, next);
 	switch_to(prev, next, prev);
 
 	barrier();
-- 
1.7.5.4

Re: [PATCH v2] rcu: Remove rcu_switch()

[Paul E. McKenney]

On Thu, Oct 11, 2012 at 01:47:16AM +0200, Frederic Weisbecker wrote:
> It's only there to call rcu_user_hooks_switch(). Let's
> just call rcu_user_hooks_switch() directly, we don't need this
> function in the middle.

Queued, thank you!

							Thanx, Paul

> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Josh Triplett <josh@joshtriplett.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Richard Weinberger <richard@nod.at>
> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> ---
>  arch/um/drivers/mconsole_kern.c |    2 +-
>  include/linux/rcupdate.h        |    2 ++
>  include/linux/sched.h           |    8 --------
>  kernel/sched/core.c             |    2 +-
>  4 files changed, 4 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
> index c17de0d..0b989af 100644
> --- a/arch/um/drivers/mconsole_kern.c
> +++ b/arch/um/drivers/mconsole_kern.c
> @@ -705,7 +705,7 @@ static void stack_proc(void *arg)
>  	struct task_struct *from = current, *to = arg;
> 
>  	to->thread.saved_task = from;
> -	rcu_switch(from, to);
> +	rcu_user_hooks_switch(from, to);
>  	switch_to(from, to, from);
>  }
> 
> diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
> index 7c968e4..5d009de 100644
> --- a/include/linux/rcupdate.h
> +++ b/include/linux/rcupdate.h
> @@ -204,6 +204,8 @@ static inline void rcu_user_enter(void) { }
>  static inline void rcu_user_exit(void) { }
>  static inline void rcu_user_enter_after_irq(void) { }
>  static inline void rcu_user_exit_after_irq(void) { }
> +static inline void rcu_user_hooks_switch(struct task_struct *prev,
> +					 struct task_struct *next) { }
>  #endif /* CONFIG_RCU_USER_QS */
> 
>  extern void exit_rcu(void);
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index fade317..c300c7c 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -1887,14 +1887,6 @@ static inline void rcu_copy_process(struct task_struct *p)
> 
>  #endif
> 
> -static inline void rcu_switch(struct task_struct *prev,
> -			      struct task_struct *next)
> -{
> -#ifdef CONFIG_RCU_USER_QS
> -	rcu_user_hooks_switch(prev, next);
> -#endif
> -}
> -
>  static inline void tsk_restore_flags(struct task_struct *task,
>  				unsigned long orig_flags, unsigned long flags)
>  {
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index dd036fe..b53a485 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -2081,7 +2081,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
>  #endif
> 
>  	/* Here we just switch the register state and the stack. */
> -	rcu_switch(prev, next);
> +	rcu_user_hooks_switch(prev, next);
>  	switch_to(prev, next, prev);
> 
>  	barrier();
> -- 
> 1.7.5.4
>