calc_timer_values

函数名称：calc_timer_values

函数原型：static void calc_timer_values(struct perf_event *event, u64 *now, u64 *enabled, u64 *running)

返回类型：void

参数：

**调用者**
名称	描述
perf_event_update_userpage	Callers need to ensure there can be no nesting of this function, otherwise* the seqlock logic goes bad. We can not serialize this because the arch* code calls this from NMI context.
perf_output_read	XXX PERF_SAMPLE_READ vs inherited events seems difficult.* The problem is that its both hard and excessively expensive to iterate the* child list, not to mention that its impossible to IPI the children running* on another CPU, from interrupt/NMI context.

函数逻辑报告