Re: [RFC][PATCH] use cycle_t instead of u64 in struct time_interpolator

[Helge Deller <deller@gmx.de>]

On Wed Jan 3 2007, Christoph Lameter wrote:
> On Tue, 2 Jan 2007, Helge Deller wrote:
> 
> > As far as I could see, this patch does not change anything for the 
> > existing architectures which use this framework (IA64 and SPARC64), 
> > since "cycles_t" is defined there as unsigned 64bit-integer anyway 
> > (which then makes this patch a no-change for them).
> 
> The 64bit nature of some entities was so far necessary to get the 
> proper accuracy of interpolation. Maybe it can be made to work with 32 bit 
> entities. The macro GET_TI_SECS must work correctly and the less bits are 
> specified in shift the less self-tuning accuracy you will get.

Yes, it was easily possible to make it 32bit-ready without loosing the accuracy.

Nevertheless, in the meantime John Stultz pointed me to the CONFIG_GENERIC_TIME framework,  and I implemented it that way:
http://git.parisc-linux.org/?p=linux-2.6.git;a=commit;h=b6de83b58b8b07f057deacdef8a95b6c32d1c4e6
http://git.parisc-linux.org/?p=linux-2.6.git;a=commit;h=f70a979c843e4610edfb2a316648fe8ae8718f69

Thus please ignore my original patch proposal. It's not needed any more...

Thanks,
Helge

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