GDB for Multiprocessor Architecture

["Nitin Gupta" <nitin.gupta@nevisnetworks.com>]

Hi,
How can GDB be used to debug an application running on a chip that has n
number of similar CPUs. These CPUs share memories and run different code
images.
I plan to do a debugging session using the hardware probe and the GDB
remote protocol. My target does not have any OS support as Linux or
RTEMS but the host is a Linux box.
My question is how can I get to know that currently GDB is talking to
which CPU? Is it possible for me to do something like 
gdb> load image1.o
gdb> CPU=1
gdb> |get register contents|
gdb> load image2.o
gdb> CPU=3
gdb> |get register contents|

and such similar stuff.

One way of implementing this is using the thread model but then each CPU
has altogether different code image to execute. Shall I have multiple
sessions of GDB, one per CPU? But again if a debug exception is raised
say a breakpoint is hit, how will I know on the host side which CPU has
hit the breakpoint.

Has anybody done a similar task on any other target? Any help on this
fron shall be grateful.

Thanks and Regards
Nitin