[ros-kernel] Kernel system time query - is it really working?

[Mike Nordell]

Hartmut Birr wrote:

> > On Behalf Of Mike Nordell
> >
> > Either I have my head screwed on the wrong way today, or
> > KeQuerySystemTime
> > requires some commenting.
> >
> > This function busy-waits for
> > SharedUserData->SystemTime.High2Part to be
> > changed.
[snip]
> This is not a busy wait. If there is an update by the timer interrupt,
> the values are changed in the sequence High2Part, LowPart and High1Part.
> The query functions read these values in the reverse sequence

That's it - not enough coffee this morning. :-)

However, as I misread it as a busy-wait, perhaps that code could benefit
from a comment on what's really going on. Both the "only-checks-once for
highword change", and "crucially in the reverse order from the update
function"?

(please read the question sign not as a question, but as a suggestion)

/Mike