diff options
| -rw-r--r-- | arch/x86/include/asm/preempt.h | 4 | ||||
| -rw-r--r-- | include/asm-generic/preempt.h | 5 | ||||
| -rw-r--r-- | include/linux/preempt.h | 19 | ||||
| -rw-r--r-- | include/linux/sched.h | 6 | ||||
| -rw-r--r-- | kernel/sched/core.c | 6 |
5 files changed, 22 insertions, 18 deletions
diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h index dca71714f860..b12f81022a6b 100644 --- a/arch/x86/include/asm/preempt.h +++ b/arch/x86/include/asm/preempt.h @@ -90,9 +90,9 @@ static __always_inline bool __preempt_count_dec_and_test(void) /* * Returns true when we need to resched and can (barring IRQ state). */ -static __always_inline bool should_resched(void) +static __always_inline bool should_resched(int preempt_offset) { - return unlikely(!raw_cpu_read_4(__preempt_count)); + return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset); } #ifdef CONFIG_PREEMPT diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h index d0a7a4753db2..0bec580a4885 100644 --- a/include/asm-generic/preempt.h +++ b/include/asm-generic/preempt.h @@ -71,9 +71,10 @@ static __always_inline bool __preempt_count_dec_and_test(void) /* * Returns true when we need to resched and can (barring IRQ state). */ -static __always_inline bool should_resched(void) +static __always_inline bool should_resched(int preempt_offset) { - return unlikely(!preempt_count() && tif_need_resched()); + return unlikely(preempt_count() == preempt_offset && + tif_need_resched()); } #ifdef CONFIG_PREEMPT diff --git a/include/linux/preempt.h b/include/linux/preempt.h index 84991f185173..bea8dd8ff5e0 100644 --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -84,13 +84,21 @@ */ #define in_nmi() (preempt_count() & NMI_MASK) +/* + * The preempt_count offset after preempt_disable(); + */ #if defined(CONFIG_PREEMPT_COUNT) -# define PREEMPT_DISABLE_OFFSET 1 +# define PREEMPT_DISABLE_OFFSET PREEMPT_OFFSET #else -# define PREEMPT_DISABLE_OFFSET 0 +# define PREEMPT_DISABLE_OFFSET 0 #endif /* + * The preempt_count offset after spin_lock() + */ +#define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET + +/* * The preempt_count offset needed for things like: * * spin_lock_bh() @@ -103,7 +111,7 @@ * * Work as expected. */ -#define SOFTIRQ_LOCK_OFFSET (SOFTIRQ_DISABLE_OFFSET + PREEMPT_DISABLE_OFFSET) +#define SOFTIRQ_LOCK_OFFSET (SOFTIRQ_DISABLE_OFFSET + PREEMPT_LOCK_OFFSET) /* * Are we running in atomic context? WARNING: this macro cannot @@ -124,7 +132,8 @@ #if defined(CONFIG_DEBUG_PREEMPT) || defined(CONFIG_PREEMPT_TRACER) extern void preempt_count_add(int val); extern void preempt_count_sub(int val); -#define preempt_count_dec_and_test() ({ preempt_count_sub(1); should_resched(); }) +#define preempt_count_dec_and_test() \ + ({ preempt_count_sub(1); should_resched(0); }) #else #define preempt_count_add(val) __preempt_count_add(val) #define preempt_count_sub(val) __preempt_count_sub(val) @@ -184,7 +193,7 @@ do { \ #define preempt_check_resched() \ do { \ - if (should_resched()) \ + if (should_resched(0)) \ __preempt_schedule(); \ } while (0) diff --git a/include/linux/sched.h b/include/linux/sched.h index 65a8a8651596..9c144657aace 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2891,12 +2891,6 @@ extern int _cond_resched(void); extern int __cond_resched_lock(spinlock_t *lock); -#ifdef CONFIG_PREEMPT_COUNT -#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET -#else -#define PREEMPT_LOCK_OFFSET 0 -#endif - #define cond_resched_lock(lock) ({ \ ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ __cond_resched_lock(lock); \ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fa5826cc612f..f5fad2b12baf 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4496,7 +4496,7 @@ SYSCALL_DEFINE0(sched_yield) int __sched _cond_resched(void) { - if (should_resched()) { + if (should_resched(0)) { preempt_schedule_common(); return 1; } @@ -4514,7 +4514,7 @@ EXPORT_SYMBOL(_cond_resched); */ int __cond_resched_lock(spinlock_t *lock) { - int resched = should_resched(); + int resched = should_resched(PREEMPT_LOCK_OFFSET); int ret = 0; lockdep_assert_held(lock); @@ -4536,7 +4536,7 @@ int __sched __cond_resched_softirq(void) { BUG_ON(!in_softirq()); - if (should_resched()) { + if (should_resched(SOFTIRQ_DISABLE_OFFSET)) { local_bh_enable(); preempt_schedule_common(); local_bh_disable(); |