Re: Timer issues?

["Michael L. Hitch" <mhitch%lightning.msu.montana.edu@localhost>]

On Thu, 13 Aug 2009, Frank Wille wrote:

> IMHO it is wrong when applying a mask of 0xfff to the result of the
> tc_get_timecount() function, which, in the amiga/dev/clock.c case, returns
> the hardclock_ticks * amiga_clk_interval + clock_tick (read directly from
> CIA timer). A mask of ~0 should work better.

  Hmm, looking at this again make me think the smaller mask shouldn't be 
needed.  the 'hardclock_ticks * amiga_clk_interval + clock_tick' should be
emulating a free-running 32 bit counter running at eclockfreq.

> But I would not dare to revert the code, because Michael wrote that he fixed
> a bug with negative values. There may be a problem somewhere else. Maybe
> Michael could comment on that.

  Someone could try reverting my change and see how it performs.  There 
was a check for a negative runtime added to sched_pstats() after my change 
that may fire [that check was also changed to only print once - when 
testing, the test for the first message could be disabled;  the reason I 
changed the vax ICR counter mask was because I was seeing multiple 
messages about the monotonic clock running backwards].

--
Michael L. Hitch                        mhitch%montana.edu@localhost
Computer Consultant
Information Technology Center
Montana State University        Bozeman, MT     USA