PS:KTIME_SEC_MAX宏和KTIME_MAX宏的值定义在在<linux/time64.h>中,前者为秒级别的ktime_t的最大值,后者就是ktime_t的最大值。 //46~56行#define ktime_sub(lhs, rhs) ((lhs) - (rhs))#define ktime_add(lhs, rhs) ((lhs) + (rhs))#define ktime_add_unsafe(lhs, rhs) ((u64) (lhs...
ktime_t end = ktime_get(); ktime_t diff = ktime_sub(end, start); ``` 通过上述操作,我们可以很方便地使用ktime在Linux内核中进行时间间隔和延迟的计算。这对于性能优化、调试和测试等场景非常有用。注意,在使用ktime的时候,我们必须保证在同一个时钟周期内进行计算,否则可能会得到不准确的结果。 除了...
ktime_t start_time = ktime_get(); //执行某些操作 ktime_t end_time = ktime_get(); s64 time_diff_ns = ktime_to_ns(ktime_sub(end_time, start_time)); ``` 5.延迟执行一段时间: ```c ktime_t delay = ktime_set(seconds, nanoseconds); ktime_t expiry_time = ktime_add(ktim...
ktime_t本质为s64类型，ktime_set用于将秒数和纳秒数转换为ktime_t时间值。ktime_add_ns和ktime_sub_ns用于对ktime_t时间变量进行加减操作。timespec64_to_ktime和ktime_to_timespec64用于结构体转换。ktime_compare用于比较ktime_t大小。ktime_after和ktime_before用于比较时间点。ktime_divns...
除了ktime_set函数之外,Linux内核中还有很多和时间相关的函数,比如ktime_add、ktime_sub、ktime_after等等,它们都是用来进行时间计算和比较的。这些函数在内核的各个模块中都有广泛的应用,保证了系统的时间相关功能能够正确高效地工作。 总的来说,ktime_set函数是Linux内核中一个非常重要的函数,它为内核开发者提供了...
ktime is a union because the initial implementation stored the time in scalar nanoseconds on 64 bit machine and in a endianess optimized timespec variant for 32bit machines. The Y2038 cleanup removed the timespec variant and switched everything to scalar nanoseconds. The union remained, but become...
(ktime_sub(later, earlier)); } static inline s64 ktime_ms_delta(const ktime_t later, const ktime_t earlier) { return ktime_to_ms(ktime_sub(later, earlier)); } static inline ktime_t ktime_add_us(const ktime_t kt, const u64 usec) { return ktime_add_ns(...