diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/asm-generic/preempt.h | 2 | ||||
-rw-r--r-- | include/linux/sched.h | 17 |
2 files changed, 13 insertions, 6 deletions
diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h index 0bec580a4885..5d8ffa3e6f8c 100644 --- a/include/asm-generic/preempt.h +++ b/include/asm-generic/preempt.h @@ -24,7 +24,7 @@ static __always_inline void preempt_count_set(int pc) * must be macros to avoid header recursion hell */ #define init_task_preempt_count(p) do { \ - task_thread_info(p)->preempt_count = PREEMPT_DISABLED; \ + task_thread_info(p)->preempt_count = FORK_PREEMPT_COUNT; \ } while (0) #define init_idle_preempt_count(p, cpu) do { \ diff --git a/include/linux/sched.h b/include/linux/sched.h index e5b8cbc4b8d6..23ca455d9582 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -599,11 +599,7 @@ struct task_cputime_atomic { .sum_exec_runtime = ATOMIC64_INIT(0), \ } -#ifdef CONFIG_PREEMPT_COUNT -#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED) -#else -#define PREEMPT_DISABLED PREEMPT_ENABLED -#endif +#define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) /* * Disable preemption until the scheduler is running -- use an unconditional @@ -613,6 +609,17 @@ struct task_cputime_atomic { */ #define INIT_PREEMPT_COUNT PREEMPT_OFFSET +/* + * Initial preempt_count value; reflects the preempt_count schedule invariant + * which states that during context switches: + * + * preempt_count() == 2*PREEMPT_DISABLE_OFFSET + * + * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. + * Note: See finish_task_switch(). + */ +#define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) + /** * struct thread_group_cputimer - thread group interval timer counts * @cputime_atomic: atomic thread group interval timers. |