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Re: simple eCos profiler


> There is a significant amount of code, most of it is not kernel code.
> Is it OK if I post a link to a webpage?  I just have to set one up :D

Yep. Or you could use bugzilla.redhat.com. Create a new enhancement
bug and attach the code using the attachment feature.

> > > P.S.  hal_ctrlc_check gets called a LOT and seems to get called
> > > more, the more pings I send it.  I haven't debugged this to find out
> > > why, but it's perplexing.  Anybody know what is going on with it?
> >
> > This function acts as the interface between the application network
> > stack and redboot. Each packet received by the application is passed
> > down to redboot to let it decide if the packet is actually for the
> > redboot stack, not the application stack.
> 
> Oh.  That name seem sort of obsfucated, but I get it.

Its historic. The redboot network stack is a recent bolt on addition.

> I will have to look at this more.  I have found that it can take up
> significant time (like 33% of the active time) if I send enough
> network traffic through it.

That does seem a lot. It is possible to disable this, but you loose
some of the network debugging facilities. Without this you cannot use
^C to interrupt a running system and tcp connections will die after a
while since the keep alive won't happen.

Actually, its possible your figure is misleading. I think interrupts
are disabled in this function before it jumps into redboot. After
redboot exits the function re-enabled interupts. Im guessing your
profiler is interrupt based? So any profiler interrupts while it is in
redboot will actually be serviced in this function once the interrupts
are re-enabled.

> I have a question.  When redboot "runs", can the application on top
> of redboot interrupt it?  I haven't investigated the relationship
> between the two very much.

Nope. 

      Andrew


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