Re: kgdb for mainline kernel: core-lite [patch 1/3]

From: George Anzinger
Date: Mon Mar 08 2004 - 17:17:50 EST

Amit S. Kale wrote:
On Monday 08 Mar 2004 3:56 pm, Andrew Morton wrote:

"Amit S. Kale" <amitkale@xxxxxxxxxxxxx> wrote:

Here are features that are present only in full kgdb:
1. Thread support (aka info threads)

argh, disaster. I discussed this with Tom a week or so ago when it looked
like this it was being chopped out and I recall being told that the
discussion was referring to something else.

Ho-hum, sorry. Can we please put this back in?

Err., well this is one of the particularly dirty parts of kgdb. That's why it's been kept away. It takes care of correct thread backtraces in some rare cases.

If you consider it an absolutely must, we can do something so that the dirty part is kept away and info threads almost always works.


I think we should just put the info threads in the core. No attempt to do any trace back from kgdb. Let them all show up in the switch code. I have a script (gdb macro) that will give a rather decent "info threads" display. Oh, we need to add one other responce to kgdb for the process info gdb command.

* This query allows the target stub to return an arbitrary string
* (or strings) giving arbitrary information about the target process.
* This is optional; the target stub isn't required to implement it.
* Syntax: qfProcessInfo request first string
* qsProcessInfo request subsequent string
* reply: 'O'<hex-encoded-string>
* 'l' last reply (empty)
What we want here is the thread name.

Here is the macro set:

set var $low_sched=0

define do_threads
if (void)$low_sched==(void)0
thread apply all do_th_lines

define do_th_lines
set var $do_th_co=0
while ($pc > $low_sched) && ($pc < $high_sched)
set var $do_th_co=$do_th_co+1
if $do_th_co==0
info remote-process
info remote-process

define set_b
set var $low_sched=scheduling_functions_start_here
set var $high_sched=scheduling_functions_end_here


George Anzinger george@xxxxxxxxxx
Preemption patch:

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