diff options
| author | Peter Zijlstra (Intel) <peterz@infradead.org> | 2021-01-18 15:12:20 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2021-02-17 14:12:42 +0100 |
| commit | b965f1ddb47daa5b8b2e2bc9c921431236830367 (patch) | |
| tree | 32cb3a3c160f26523f6d07a9ddadaf25df7c13a3 /include | |
| parent | 6ef869e0647439af0fc28dde162d33320d4e1dd7 (diff) | |
preempt/dynamic: Provide cond_resched() and might_resched() static calls
Provide static calls to control cond_resched() (called in !CONFIG_PREEMPT)
and might_resched() (called in CONFIG_PREEMPT_VOLUNTARY) to that we
can override their behaviour when preempt= is overriden.
Since the default behaviour is full preemption, both their calls are
ignored when preempt= isn't passed.
[fweisbec: branch might_resched() directly to __cond_resched(), only
define static calls when PREEMPT_DYNAMIC]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-6-frederic@kernel.org
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/kernel.h | 23 | ||||
| -rw-r--r-- | include/linux/sched.h | 27 |
2 files changed, 43 insertions, 7 deletions
diff --git a/include/linux/kernel.h b/include/linux/kernel.h index f7902d8c1048..cfd3d349f905 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -15,7 +15,7 @@ #include <linux/typecheck.h> #include <linux/printk.h> #include <linux/build_bug.h> - +#include <linux/static_call_types.h> #include <asm/byteorder.h> #include <uapi/linux/kernel.h> @@ -81,11 +81,26 @@ struct pt_regs; struct user; #ifdef CONFIG_PREEMPT_VOLUNTARY -extern int _cond_resched(void); -# define might_resched() _cond_resched() + +extern int __cond_resched(void); +# define might_resched() __cond_resched() + +#elif defined(CONFIG_PREEMPT_DYNAMIC) + +extern int __cond_resched(void); + +DECLARE_STATIC_CALL(might_resched, __cond_resched); + +static __always_inline void might_resched(void) +{ + static_call(might_resched)(); +} + #else + # define might_resched() do { } while (0) -#endif + +#endif /* CONFIG_PREEMPT_* */ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP extern void ___might_sleep(const char *file, int line, int preempt_offset); diff --git a/include/linux/sched.h b/include/linux/sched.h index e1152227bb79..2f35594b8b53 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1871,11 +1871,32 @@ static inline int test_tsk_need_resched(struct task_struct *tsk) * value indicates whether a reschedule was done in fact. * cond_resched_lock() will drop the spinlock before scheduling, */ -#ifndef CONFIG_PREEMPTION -extern int _cond_resched(void); +#if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) +extern int __cond_resched(void); + +#ifdef CONFIG_PREEMPT_DYNAMIC + +DECLARE_STATIC_CALL(cond_resched, __cond_resched); + +static __always_inline int _cond_resched(void) +{ + return static_call(cond_resched)(); +} + #else + +static inline int _cond_resched(void) +{ + return __cond_resched(); +} + +#endif /* CONFIG_PREEMPT_DYNAMIC */ + +#else + static inline int _cond_resched(void) { return 0; } -#endif + +#endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */ #define cond_resched() ({ \ ___might_sleep(__FILE__, __LINE__, 0); \ |