[U-Boot] how to limit sandbox to a single thread/core?

[Abraham V.]

On Tue, Dec 17, 2013 at 2:00 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi,
>
> On 13 December 2013 01:47, Abraham V. <abraham.varricatt at vvdntech.com> wrote:
>> Hello,
>>
>> I just discovered that uboot has a "sandbox" build - output binary is
>> a standard linux application. This prompted me to try stepping through
>> the code with gdb and I'm running into an annoyance.
>>
>> The sandbox binary is splitting into 4 threads (I'm guessing one for
>> each of my cores, am running this on an intel i3). This results in gdb
>> jumping between the different threads every once in a while.
>>
>> Is there anyway to setup the sandbox to run as a single thread?
>
> This is news to me - I have not hit this problem yet. Can you see what
> the threads are?
>
> Regards,
> Simon

I'm ... embarrassed to report that this is a false alarm. Took me a
couple of days and I was about to send a reply today morning when I
saw your response. What happened is that I used the eclipse-cdt
debugger to try tracing the sandbox application. An interesting
'feature' of this debugger is that it shows which core a process is
running on. Here are a few (links) screenshots,

http://imageshack.us/a/img14/2202/ze37.png
http://imageshack.us/a/img855/1153/uwul.png
http://imageshack.us/a/img585/8499/ibz3.png

It wasn't until yesterday when I realized that, while the application
was jumping between cores, the thread number was exactly the same - it
wasn't a multi-threaded application, but a single threaded one just
bouncing around! This puzzled me so much that I even started a SO
question over the matter,

http://stackoverflow.com/questions/20608032/while-debugging-will-a-single-threaded-application-jump-between-cores

Turns out that the scheduler knocked me off-balance. Can't believe I'm
saying this, but I miss the days when everything ran on a single
thread/processor core.

A little embarrassed,
Abraham V.