[PATCH 0/3] sched_clock updates

[Steven Rostedt]

Working with ftrace on linux-tip, I found a few problems with the sched_clock
code that is suppose to help an unstable TSC keep accurate time. The
problem I was seeing was on a box with a stable TSC. The time would
jump around a lot. One would think that code to help unstable TSC keep
time would not be a problem with a stable TSC.

The main change was the patch that handled the dynamic ticks. That was
the culprit of bein off by several jiffies.

With these patches applied, ftrace is quite a bit better with respect to time.
But there is still jumps that happen that do not happen with sched_clock.

I'm suspecting that the problems that still exist have more to do with
time updates or a drift between the TSC and the clock used for GTOD.

Anyway, enjoy,

-- Steve

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