16 Jan
2017
16 Jan
'17
4:15 a.m.
Yeah, saw it. I'm of the opinion that you aren't really truly an OS
person unless you've written a context switcher. I wrote one for a
user level threading package I did for Udi Manber as a grad student.
I did most of the work in C and then dropped to assembler for the
trampoline.
It's really not that complicated, I think people make it out to be
a bigger deal than it is. You're saving state (registers), switching
stacks, and changing the return address so you return in the new
process.
Well, not that complicated on a simple machine line a VAX or a 68K
or a PDP11. I sort of stopped playing in assembler when super scalar
out of order stuff came around and I couldn't get the mental picture
of what was where.
On Mon, Jan 16, 2017 at 11:44:44AM +1000, Warren Toomey wrote:
http://thenewstack.io/not-expected-understand-explainer/
in case you haven't seen it yet.
Cheers, Warren
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Larry McVoy lm at mcvoy.com http://www.mcvoy.com/lm