| #ifndef __ASM_PREEMPT_H |
| #define __ASM_PREEMPT_H |
| |
| #include <linux/thread_info.h> |
| |
| #define PREEMPT_ENABLED (0) |
| |
| static __always_inline int preempt_count(void) |
| { |
| return current_thread_info()->preempt_count; |
| } |
| |
| static __always_inline int *preempt_count_ptr(void) |
| { |
| return ¤t_thread_info()->preempt_count; |
| } |
| |
| static __always_inline void preempt_count_set(int pc) |
| { |
| *preempt_count_ptr() = pc; |
| } |
| |
| /* |
| * must be macros to avoid header recursion hell |
| */ |
| #define init_task_preempt_count(p) do { \ |
| task_thread_info(p)->preempt_count = PREEMPT_DISABLED; \ |
| } while (0) |
| |
| #define init_idle_preempt_count(p, cpu) do { \ |
| task_thread_info(p)->preempt_count = PREEMPT_ENABLED; \ |
| } while (0) |
| |
| static __always_inline void set_preempt_need_resched(void) |
| { |
| } |
| |
| static __always_inline void clear_preempt_need_resched(void) |
| { |
| } |
| |
| static __always_inline bool test_preempt_need_resched(void) |
| { |
| return false; |
| } |
| |
| /* |
| * The various preempt_count add/sub methods |
| */ |
| |
| static __always_inline void __preempt_count_add(int val) |
| { |
| *preempt_count_ptr() += val; |
| } |
| |
| static __always_inline void __preempt_count_sub(int val) |
| { |
| *preempt_count_ptr() -= val; |
| } |
| |
| static __always_inline bool __preempt_count_dec_and_test(void) |
| { |
| /* |
| * Because of load-store architectures cannot do per-cpu atomic |
| * operations; we cannot use PREEMPT_NEED_RESCHED because it might get |
| * lost. |
| */ |
| return !--*preempt_count_ptr() && tif_need_resched(); |
| } |
| |
| /* |
| * Returns true when we need to resched and can (barring IRQ state). |
| */ |
| static __always_inline bool should_resched(int preempt_offset) |
| { |
| return unlikely(preempt_count() == preempt_offset && |
| tif_need_resched()); |
| } |
| |
| #ifdef CONFIG_PREEMPT |
| extern asmlinkage void preempt_schedule(void); |
| #define __preempt_schedule() preempt_schedule() |
| |
| #ifdef CONFIG_CONTEXT_TRACKING |
| extern asmlinkage void preempt_schedule_context(void); |
| #define __preempt_schedule_context() preempt_schedule_context() |
| #endif |
| #endif /* CONFIG_PREEMPT */ |
| |
| #endif /* __ASM_PREEMPT_H */ |