Messages in this thread | | | Date | Sun, 15 May 2005 11:22:27 +0100 | From | James Courtier-Dutton <> | Subject | Re: IA64 implementation of timesource for new time of day subsystem |
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Christoph Lameter wrote: > On Fri, 13 May 2005, john stultz wrote: > > >>I look forward to your comments and feedback. > > > Here is the implementation of the IA64 timesources for the new time of > day subsystem. > > This is quite straighforward. Thanks John. However, the ITC > interpolator can no longer use MMIO in SMP situations since there is no > provision for jitter compensation in the new time of day subsystem. I have > implemented that via a function now which will slow down clock access > for non SGI IA64 hardware significantly since it will not be able to use > the fastcall anymore. > > I am working on the fastcall but I would need a couple of changes > to the core code to make the following symbols non-static since they > will need to be accessed from the fast syscall handler: > > timesource > system_time > wall_time_offset > offset_base >
Will this mean that Linux will have a monotonic time source? For media players we need a timesource that does not change under any circumstances. e.g. User changes the clock time, the monotonic time source should not change. The monotonic time source should just start at 0 at power on, and continually increase accurately over time. I.e. A very accurate "uptime" measurement.
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