[PATCH] sched/core: Remove the unused schedule_user() function

[PATCH] sched/core: Remove the unused schedule_user() function

[Eiichi Tsukata]

Since commit 02bc7768fe44 ("x86/asm/entry/64: Migrate error and IRQ exit
work to C and remove old assembly code"), it's no longer used.

Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
---
 kernel/sched/core.c | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2b037f195473..0079bebe0086 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3973,25 +3973,6 @@ void __sched schedule_idle(void)
 	} while (need_resched());
 }
 
-#ifdef CONFIG_CONTEXT_TRACKING
-asmlinkage __visible void __sched schedule_user(void)
-{
-	/*
-	 * If we come here after a random call to set_need_resched(),
-	 * or we have been woken up remotely but the IPI has not yet arrived,
-	 * we haven't yet exited the RCU idle mode. Do it here manually until
-	 * we find a better solution.
-	 *
-	 * NB: There are buggy callers of this function.  Ideally we
-	 * should warn if prev_state != CONTEXT_USER, but that will trigger
-	 * too frequently to make sense yet.
-	 */
-	enum ctx_state prev_state = exception_enter();
-	schedule();
-	exception_exit(prev_state);
-}
-#endif
-
 /**
  * schedule_preempt_disabled - called with preemption disabled
  *
-- 
2.21.0

Re: [PATCH] sched/core: Remove the unused schedule_user() function

[Qais Yousef]

On 07/28/19 01:55, Eiichi Tsukata wrote:
> Since commit 02bc7768fe44 ("x86/asm/entry/64: Migrate error and IRQ exit
> work to C and remove old assembly code"), it's no longer used.

It seems to me that powerpc and sparc are still using it?

$ git grep SCHEDULE_USER
arch/powerpc/include/asm/context_tracking.h:#define SCHEDULE_USER bl    schedule_user
arch/powerpc/include/asm/context_tracking.h:#define SCHEDULE_USER bl    schedule
arch/powerpc/kernel/entry_64.S: SCHEDULE_USER
arch/sparc/kernel/rtrap_64.S:# define SCHEDULE_USER schedule_user
arch/sparc/kernel/rtrap_64.S:# define SCHEDULE_USER schedule
arch/sparc/kernel/rtrap_64.S:           call                    SCHEDULE_USER

Cheers

--
Qais Yousef

> 
> Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
> ---
>  kernel/sched/core.c | 19 -------------------
>  1 file changed, 19 deletions(-)
> 
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 2b037f195473..0079bebe0086 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -3973,25 +3973,6 @@ void __sched schedule_idle(void)
>  	} while (need_resched());
>  }
>  
> -#ifdef CONFIG_CONTEXT_TRACKING
> -asmlinkage __visible void __sched schedule_user(void)
> -{
> -	/*
> -	 * If we come here after a random call to set_need_resched(),
> -	 * or we have been woken up remotely but the IPI has not yet arrived,
> -	 * we haven't yet exited the RCU idle mode. Do it here manually until
> -	 * we find a better solution.
> -	 *
> -	 * NB: There are buggy callers of this function.  Ideally we
> -	 * should warn if prev_state != CONTEXT_USER, but that will trigger
> -	 * too frequently to make sense yet.
> -	 */
> -	enum ctx_state prev_state = exception_enter();
> -	schedule();
> -	exception_exit(prev_state);
> -}
> -#endif
> -
>  /**
>   * schedule_preempt_disabled - called with preemption disabled
>   *
> -- 
> 2.21.0
> 

Re: [PATCH] sched/core: Remove the unused schedule_user() function

[Eiichi Tsukata]

On 2019/07/29 17:30, Qais Yousef wrote:
> On 07/28/19 01:55, Eiichi Tsukata wrote:
>> Since commit 02bc7768fe44 ("x86/asm/entry/64: Migrate error and IRQ exit
>> work to C and remove old assembly code"), it's no longer used.
> 
> It seems to me that powerpc and sparc are still using it?
> 
> $ git grep SCHEDULE_USER
> arch/powerpc/include/asm/context_tracking.h:#define SCHEDULE_USER bl    schedule_user
> arch/powerpc/include/asm/context_tracking.h:#define SCHEDULE_USER bl    schedule
> arch/powerpc/kernel/entry_64.S: SCHEDULE_USER
> arch/sparc/kernel/rtrap_64.S:# define SCHEDULE_USER schedule_user
> arch/sparc/kernel/rtrap_64.S:# define SCHEDULE_USER schedule
> arch/sparc/kernel/rtrap_64.S:           call                    SCHEDULE_USER
> 
> Cheers
> 
> --
> Qais Yousef
> 

Sorry, I misused cscope. The function is still used as you say.

Thanks

Eiichi

Re: [PATCH] sched/core: Remove the unused schedule_user() function

[Peter Zijlstra]

On Sun, Jul 28, 2019 at 01:55:13AM +0900, Eiichi Tsukata wrote:
> Since commit 02bc7768fe44 ("x86/asm/entry/64: Migrate error and IRQ exit
> work to C and remove old assembly code"), it's no longer used.

Thanks!