Re: bottom half

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

> "Runs on kernel stack in kernel space" is not the same thing as the Linux
> concept of bottom half. :-)
I don't know what the Linux (or VMS or Windows) concept of "nottom half" is.
I thought I knew what the BSD concept of kernel halves is.

> I don't know what the figured referred to is, 
Figure 3.1 Run-time structure of the kernel

> but the text quoted do not say "bottom half" at least...
The text describes what "bottom half of the kernel" in the figure means.

To eleborate, as I seem to have been too cryptic in my references: I learned 
the terms top and bottom half from "The Design and Implementation of the 
4.4BSD Operating System" by McKusick, Bostic, Karels and Quaterman. The 
text on page 51 explains "The bottom half of the kernel comprises routines 
that are invoked to handle hardware interrupts." and the figure 3.1 above 
explains "Never scheduled, cannot block. Runs on kernel stack in kernel 
address space."

Now it may well be that things have changed, my understanding is out-dated 
and NetBSD handles interrupts in a conceptually different way from 4.4BSD.

But if things have not changed, I think a documentation on NetBSD's locking 
mechanisms (thanks go to Kamil for writing this!) may well use the terms 
the definite reference on 4.4BSD uses, no matter what penguin addicts use 
the term for. In fact I think it should because I can't stand people picking 
up well-established terms, re-defining them and then refusing to accept 
the traditional definition. Ever tried to talk to someone grown up with 
git about what a patch is?