Question about UTCB
benjl at cse.unsw.edu.au
Thu Feb 23 23:35:13 CET 2006
On Thu Feb 23, 2006 at 17:33:43 -0500, Jonathan S. Shapiro wrote:
>On Fri, 2006-02-24 at 09:18 +1100, Benno wrote:
>> >When a process is preempted, where are its registers stored? Are the
>> >stored in the UTCB, or are they stored in some data structure that is
>> >only accessible to the kernel?
>> They are stored in the thread's TCB, which is kernel private data.
>So, in particular, the saved registers are not accessable to normal load
>and store instructions that might occur on a second processor. Correct?
Correct. (Of course there could be the potential to do some neat
things if they *were* available, but that raises a whole can of
worms, and unfortunately I don't have time to go over that design
discussion again ;)
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