Re: [Discuss-gnuradio] shmat issue

[Eric Blossom]

On Wed, Oct 20, 2010 at 01:02:15PM -0400, Philip Balister wrote:
> On 10/19/2010 10:51 PM, Eric Blossom wrote:
> >
> >>In both cases I can hear the dial tone fine. I'm curious why I get
> >>the shmat error the first time only.
> >
> >You should see it only once ever, if the program can write to
> >~/.gnuradio/prefs.  Generally this gets written during "make check".
> >
> >Does "make check" work?
> 
> Insert whining about make check for the cross compiled case :)
> 
> >Why are you running as root?
> 
> I am lazy :)

And foolish :)

> >>It looks like gnuradio falls
> >>back to another method of creating the shared segment.
> >
> >Yes it does.
> >
> >>I'd like to resolve the shmat issue though,
> >
> >Set a breakpoint with gdb, or add printfs.
> 
> OK, it looks like x86 sets SHMLBA to PAGE_SIZE and arm uses 4 *
> PAGE_SIZE. Need to puzzle through this a little more. This is the
> failing check in the kernel.

OK.  What's PAGE_SIZE on arm?

I wonder how we can determine the actual value of SHMLBA at runtime?
We currently use the result of gr_pagesize() as the required alignment value.

Eric