2012-10-10 23:47:27

by Frederic Weisbecker

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

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 <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Richard Weinberger <[email protected]>
Signed-off-by: Paul E. McKenney <[email protected]>
---
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

2012-10-11 00:50:50

by Paul E. McKenney

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

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 <[email protected]>
> Cc: Josh Triplett <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Cc: Richard Weinberger <[email protected]>
> Signed-off-by: Paul E. McKenney <[email protected]>
> ---
> 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
>