[PATCH] Add sched_clock to AT91 TCB clocksource driver

Remy Bohmer linux at bohmer.net
Mon Aug 1 16:00:00 EDT 2011


>> But late_time_init does it before the sched_clock is declared stable.
>> Until that point sched_clock will always return zero, as such we can
>> IMHO safely assume that the scheduler is designed such that it can
>> handle fixed zero timestamps for a while.
> You're confused.
> If you provide your own sched_clock(), that's what is used by everyone
> who calls sched_clock() both before and after sched_clock_init() has
> been called.
> sched_clock_cpu() and cpu_clock() both will return zero up until
> sched_clock_init() has been called, but sched_clock() itself may not.
> And these parts of the scheduler I'm talking about use sched_clock()
> itself, not sched_clock_cpu() nor cpu_clock().

Yep. You are right. I was confused... Sorry.

Kind regards,


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