Messages in this thread | | | Date | Fri, 02 Jan 2015 08:31:33 -0700 | From | David Ahern <> | Subject | Re: [PATCH v2 3/3] X86: Add a thread cpu time implementation to vDSO |
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On 1/1/15 7:59 PM, Shaohua Li wrote: > I'm wondering how we could use the perf to implament a clock_gettime. > reading the perf fd or using ioctl is slow so reading the mmap > ringbuffer is the only option. But as far as I know the ringbuffer has > data only when an event is generated. Between two events, there is > nothing we can read from the ringbuffer. Then how can application get > time info in the interval?
Are you wanting to read perf_clock from userspace?
David
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