Problem with timecounters and memory model

[Sebastian Huber]

----- Poul-Henning Kamp <phk at freebsd.org> schrieb:
> --------
> In message <55686D31.1060408 at embedded-brains.de>, Sebastian Huber writes:
> 
> >> How often do you "wind" the timecounter ?
> >
> >More often than necessary. About 1000 times a second with only one=20
> >timehand (this is a hack to support legacy systems). The test case is:
> 
> If you only have one timehand, I can't see how it can work without
> locks ?

In RTEMS we have two build time configurations: uni-processor and SMP.  In the uni-processor configuration we have only one timehand.  The windup function is called in interrupt context with interrupts disabled.  We have the one timehand limitation since not every supported hardware provides a free running counter.  In the SMP configuration we use the default 10 timehands.

-- 
Sebastian Huber, embedded brains GmbH

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