[PATCH 3/5] sched: dynamic: Simplify preempt_schedule{,_notrace}()
From: Mark Rutland
Date: Fri Jul 03 2026 - 09:34:59 EST
PREEMPT_DYNAMIC is now limited to the FULL and LAZY preemption models.
In either model, both preempt_schedule() and preempt_schedule_notrace()
are always called and never disabled.
Remove the unnecessary code for these when PREEMPT_DYNAMIC is selected.
Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: John Stultz <jstultz@xxxxxxxxxx>
Cc: Juri Lelli <juri.lelli@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Valentin Schneider <vschneid@xxxxxxxxxx>
Cc: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
---
arch/arm64/include/asm/preempt.h | 10 ------
arch/s390/include/asm/preempt.h | 11 -------
arch/x86/include/asm/preempt.h | 28 -----------------
include/asm-generic/preempt.h | 10 ------
kernel/sched/core.c | 52 --------------------------------
5 files changed, 111 deletions(-)
diff --git a/arch/arm64/include/asm/preempt.h b/arch/arm64/include/asm/preempt.h
index 932ea4b620428..506dab34dddb2 100644
--- a/arch/arm64/include/asm/preempt.h
+++ b/arch/arm64/include/asm/preempt.h
@@ -84,19 +84,9 @@ static inline bool should_resched(int preempt_offset)
void preempt_schedule(void);
void preempt_schedule_notrace(void);
-#ifdef CONFIG_PREEMPT_DYNAMIC
-
-void dynamic_preempt_schedule(void);
-#define __preempt_schedule() dynamic_preempt_schedule()
-void dynamic_preempt_schedule_notrace(void);
-#define __preempt_schedule_notrace() dynamic_preempt_schedule_notrace()
-
-#else /* CONFIG_PREEMPT_DYNAMIC */
-
#define __preempt_schedule() preempt_schedule()
#define __preempt_schedule_notrace() preempt_schedule_notrace()
-#endif /* CONFIG_PREEMPT_DYNAMIC */
#endif /* CONFIG_PREEMPTION */
#endif /* __ASM_PREEMPT_H */
diff --git a/arch/s390/include/asm/preempt.h b/arch/s390/include/asm/preempt.h
index 6e5821bb047e2..797efcbfe394a 100644
--- a/arch/s390/include/asm/preempt.h
+++ b/arch/s390/include/asm/preempt.h
@@ -148,20 +148,9 @@ static __always_inline bool should_resched(int preempt_offset)
void preempt_schedule(void);
void preempt_schedule_notrace(void);
-#ifdef CONFIG_PREEMPT_DYNAMIC
-
-void dynamic_preempt_schedule(void);
-void dynamic_preempt_schedule_notrace(void);
-#define __preempt_schedule() dynamic_preempt_schedule()
-#define __preempt_schedule_notrace() dynamic_preempt_schedule_notrace()
-
-#else /* CONFIG_PREEMPT_DYNAMIC */
-
#define __preempt_schedule() preempt_schedule()
#define __preempt_schedule_notrace() preempt_schedule_notrace()
-#endif /* CONFIG_PREEMPT_DYNAMIC */
-
#endif /* CONFIG_PREEMPTION */
#endif /* __ASM_PREEMPT_H */
diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index 578441db09f0b..14002c2abff44 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -109,43 +109,15 @@ static __always_inline bool should_resched(int preempt_offset)
extern asmlinkage void preempt_schedule(void);
extern asmlinkage void preempt_schedule_thunk(void);
-#define preempt_schedule_dynamic_enabled preempt_schedule_thunk
-#define preempt_schedule_dynamic_disabled NULL
-
extern asmlinkage void preempt_schedule_notrace(void);
extern asmlinkage void preempt_schedule_notrace_thunk(void);
-#define preempt_schedule_notrace_dynamic_enabled preempt_schedule_notrace_thunk
-#define preempt_schedule_notrace_dynamic_disabled NULL
-
-#ifdef CONFIG_PREEMPT_DYNAMIC
-
-DECLARE_STATIC_CALL(preempt_schedule, preempt_schedule_dynamic_enabled);
-
-#define __preempt_schedule() \
-do { \
- __STATIC_CALL_MOD_ADDRESSABLE(preempt_schedule); \
- asm volatile ("call " STATIC_CALL_TRAMP_STR(preempt_schedule) : ASM_CALL_CONSTRAINT); \
-} while (0)
-
-DECLARE_STATIC_CALL(preempt_schedule_notrace, preempt_schedule_notrace_dynamic_enabled);
-
-#define __preempt_schedule_notrace() \
-do { \
- __STATIC_CALL_MOD_ADDRESSABLE(preempt_schedule_notrace); \
- asm volatile ("call " STATIC_CALL_TRAMP_STR(preempt_schedule_notrace) : ASM_CALL_CONSTRAINT); \
-} while (0)
-
-#else /* PREEMPT_DYNAMIC */
-
#define __preempt_schedule() \
asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT);
#define __preempt_schedule_notrace() \
asm volatile ("call preempt_schedule_notrace_thunk" : ASM_CALL_CONSTRAINT);
-#endif /* PREEMPT_DYNAMIC */
-
#endif /* PREEMPTION */
#endif /* __ASM_PREEMPT_H */
diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h
index 51f8f3881523a..26309df2a42f3 100644
--- a/include/asm-generic/preempt.h
+++ b/include/asm-generic/preempt.h
@@ -82,19 +82,9 @@ static __always_inline bool should_resched(int preempt_offset)
extern asmlinkage void preempt_schedule(void);
extern asmlinkage void preempt_schedule_notrace(void);
-#if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
-
-void dynamic_preempt_schedule(void);
-void dynamic_preempt_schedule_notrace(void);
-#define __preempt_schedule() dynamic_preempt_schedule()
-#define __preempt_schedule_notrace() dynamic_preempt_schedule_notrace()
-
-#else /* !CONFIG_PREEMPT_DYNAMIC || !CONFIG_HAVE_PREEMPT_DYNAMIC_KEY*/
-
#define __preempt_schedule() preempt_schedule()
#define __preempt_schedule_notrace() preempt_schedule_notrace()
-#endif /* CONFIG_PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_KEY*/
#endif /* CONFIG_PREEMPTION */
#endif /* __ASM_PREEMPT_H */
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 84ec93694d718..f88b9ef70a0dd 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7439,27 +7439,6 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
NOKPROBE_SYMBOL(preempt_schedule);
EXPORT_SYMBOL(preempt_schedule);
-#ifdef CONFIG_PREEMPT_DYNAMIC
-# ifdef CONFIG_HAVE_PREEMPT_DYNAMIC_CALL
-# ifndef preempt_schedule_dynamic_enabled
-# define preempt_schedule_dynamic_enabled preempt_schedule
-# define preempt_schedule_dynamic_disabled NULL
-# endif
-DEFINE_STATIC_CALL(preempt_schedule, preempt_schedule_dynamic_enabled);
-EXPORT_STATIC_CALL_TRAMP(preempt_schedule);
-# elif defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
-static DEFINE_STATIC_KEY_TRUE(sk_dynamic_preempt_schedule);
-void __sched notrace dynamic_preempt_schedule(void)
-{
- if (!static_branch_unlikely(&sk_dynamic_preempt_schedule))
- return;
- preempt_schedule();
-}
-NOKPROBE_SYMBOL(dynamic_preempt_schedule);
-EXPORT_SYMBOL(dynamic_preempt_schedule);
-# endif
-#endif /* CONFIG_PREEMPT_DYNAMIC */
-
/**
* preempt_schedule_notrace - preempt_schedule called by tracing
*
@@ -7512,27 +7491,6 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
}
EXPORT_SYMBOL_GPL(preempt_schedule_notrace);
-#ifdef CONFIG_PREEMPT_DYNAMIC
-# if defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
-# ifndef preempt_schedule_notrace_dynamic_enabled
-# define preempt_schedule_notrace_dynamic_enabled preempt_schedule_notrace
-# define preempt_schedule_notrace_dynamic_disabled NULL
-# endif
-DEFINE_STATIC_CALL(preempt_schedule_notrace, preempt_schedule_notrace_dynamic_enabled);
-EXPORT_STATIC_CALL_TRAMP(preempt_schedule_notrace);
-# elif defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
-static DEFINE_STATIC_KEY_TRUE(sk_dynamic_preempt_schedule_notrace);
-void __sched notrace dynamic_preempt_schedule_notrace(void)
-{
- if (!static_branch_unlikely(&sk_dynamic_preempt_schedule_notrace))
- return;
- preempt_schedule_notrace();
-}
-NOKPROBE_SYMBOL(dynamic_preempt_schedule_notrace);
-EXPORT_SYMBOL(dynamic_preempt_schedule_notrace);
-# endif
-#endif
-
#endif /* CONFIG_PREEMPTION */
/*
@@ -7830,8 +7788,6 @@ EXPORT_SYMBOL(__cond_resched_rwlock_write);
# endif
/*
- * SC:preempt_schedule
- * SC:preempt_schedule_notrace
* SC:irqentry_exit_cond_resched
*
*
@@ -7842,14 +7798,10 @@ EXPORT_SYMBOL(__cond_resched_rwlock_write);
* (unselectable)
*
* FULL:
- * preempt_schedule <- preempt_schedule
- * preempt_schedule_notrace <- preempt_schedule_notrace
* irqentry_exit_cond_resched <- irqentry_exit_cond_resched
* dynamic_preempt_lazy <- false
*
* LAZY:
- * preempt_schedule <- preempt_schedule
- * preempt_schedule_notrace <- preempt_schedule_notrace
* irqentry_exit_cond_resched <- irqentry_exit_cond_resched
* dynamic_preempt_lazy <- true
*/
@@ -7894,8 +7846,6 @@ static void __sched_dynamic_update(int mode)
{
switch (mode) {
case preempt_dynamic_full:
- preempt_dynamic_enable(preempt_schedule);
- preempt_dynamic_enable(preempt_schedule_notrace);
preempt_dynamic_enable(irqentry_exit_cond_resched);
preempt_dynamic_key_disable(preempt_lazy);
if (mode != preempt_dynamic_mode)
@@ -7903,8 +7853,6 @@ static void __sched_dynamic_update(int mode)
break;
case preempt_dynamic_lazy:
- preempt_dynamic_enable(preempt_schedule);
- preempt_dynamic_enable(preempt_schedule_notrace);
preempt_dynamic_enable(irqentry_exit_cond_resched);
preempt_dynamic_key_enable(preempt_lazy);
if (mode != preempt_dynamic_mode)
--
2.30.2