[uClinux-dev] armnommu and pthread

[Jamie Lokier]

David McCullough wrote:
> > daemon mode is not possible under uclibc, so maybe it is the same with
> > pthread.
> 
> daemon's are possible under uClinux,  but the standard way of
> daemonising is not.  It's fairly easy to work around.  Have a look at:
> 
> 	http://www.ucdot.org/article.pl?sid=04/08/04/1243240

I don't see anything about daemons at that link, nor when searching
for "daemon" on ucdot.

However, I do have a working version of the daemon() function for
armnommu which I use in my own projects :-)  (And which I submitted to
a Busybox bug report, but I don't think anyone noticed).  It is
possible using clone() and a few instructions of assembly.

> Most of the uCLinux/malloc issues relate to fragmentation.  Have a look
> at the ucdot FAQ's for more info:
> 
> 	http://www.ucdot.org/faq.pl

Yes, definitely!  Fragmentation is ridiculous - 12MB free and can't
allocate 256kB to start an executable.  Painful.  Thank goodness for
XIP-in-RAM to save a bit of space.

If streaming files at video rates, I'd add kswapd tuning and the right
choice of page_alloc.c vs. page_alloc2.c are important too.

-- Jamie