tracepoint frames

[Jim Blandy]

"Newman, Mark (N-Superior Technical Resource Inc)" <mark.newman@lmco.com> writes:
> The question has come up as to what needs to be collected when a
> tracepoint is hit.  I understand that a "frame" needs to be
> collected.  Can someone tell me what a "frame" is.  Is it a stack
> frame, a trace frame, or what?

Well, we do have trace frames; a trace frame is the clump of
information collected for a single tracepoint hit.  It includes
registers, and assorted regions of memory.

You can also ask a trace frame to collect things like local variables,
arguments, or registers.  But all that gets parsed by the code in
tracepoint.c and turned into a 'struct collection_list', that's just a
set of registers, memory regions, and agent expressions to collect;
it's all parsed for you.  So at that level, there are no frames any
more --- everything is explicit

But I don't feel like I've answered the question.  In what context did
it come up?