How can I trace through the kernel or other processes ?

HI I am trying to figure out how to trace the execution of the kernel.
What I have obtained so far is just use printf but it is kind of
annoying since the kernel is working so fast that I can't read the
msgs.

Is there any way to record the msgs of the kernel so that I can read
later ?
Some guy suggested that it could be debugged with the computers on
Minix or other system using serial line. I am short of knowledge about
that.

Can anybody who knows about this tell me ?

Thanks in advance.

Tyson M Kim

All,
[color=blue]
> HI I am trying to figure out how to trace the execution of the kernel.
> What I have obtained so far is just use printf but it is kind of
> annoying since the kernel is working so fast that I can't read the
> msgs.
>
> Is there any way to record the msgs of the kernel so that I can read
> later ?
> Some guy suggested that it could be debugged with the computers on
> Minix or other system using serial line. I am short of knowledge about
> that.
>
> Can anybody who knows about this tell me ?[/color]

I think the easiest way to trace low-level kernel operation is
running minix in a emulator.

There is code in the kernel that will print all debug output to the
serial port as well - see the do_serial_debug variable in tested in
kprintf.c. This is also convenient together with an emulator.

Emulators also let you set breakpoints, watchpoints, and the like.

Good luck.

=Ben

think the easiest way to trace low-level kernel operation is[color=blue]
> running minix in a emulator.[/color]
[color=blue]
> There is code in the kernel that will print all debug output to the
> serial port as well - see the do_serial_debug variable in tested in
> kprintf.c. This is also convenient together with an emulator.[/color]

I really appreciate this. I didn't have chace to look at it. You mean
minix 3 ?
[color=blue]
> Emulators also let you set breakpoints, watchpoints, and the like.[/color]

I use vmware. What you mean is bochs or qemu ?

Thanks Ben
I give it a try

Tyson

All,
[color=blue]
> I really appreciate this. I didn't have chace to look at it. You mean
> minix 3 ?[/color]

Yep, this is a relatively new addition. But if you want to do this
under minix 2, it shouldn't be too hard to backport it.
[color=blue][color=green]
>> Emulators also let you set breakpoints, watchpoints, and the like.[/color]
> I use vmware. What you mean is bochs or qemu ?[/color]

Yes. I don't know if vmware will let you do this kind of thing..

=Ben