Re: [avr32-libc-devel] Memory allocation design for AVR32 Libc

[Kaushik, P. <Pra...@at...>]

> -----Original Message-----
> From: Weddington, Eric
> Sent: Saturday, July 24, 2010 2:54 AM
> To: Kaushik, Praveen_Kumar; 'avr...@li...'
> Subject: RE: [avr32-libc-devel] Memory allocation design for AVR32 Libc
> 
> 
> 
> > -----Original Message-----
> > From: Kaushik, Praveen_Kumar
> > Sent: Friday, July 23, 2010 3:29 AM
> > To: Weddington, Eric; 'avr...@li...'
> > Subject: RE: [avr32-libc-devel] Memory allocation design for
> > AVR32 Libc
> >
> > As each OS handles the memory allocation in different manner,
> > so we need to look at their memory management techniques. So
> > can you provide me a list of all the operating systems
> > supported by our tool chain?
> 
> I'm not sure that there is a comprehensive list. Looking at the Atmel web
> site, I see that uCOS/II is available for the AVR32. I seem to recall
> FreeRTOS is available for the AVR32.
> 
> But we shouldn't tailor the memory allocation routines for just those
> operating systems. I wouldn't want to limit the customers choice in
> operating systems for the future. We need to come up with a decent,
> generic memory allocation routines that will work for RTOSes as well as
> applications that don't use an RTOS.
> 
> Do you think that this could be done?
> 

I am not sure if a single implementation can work for all RTOS and no OS situations as well. I went through uC/OS-II and freeRTOS's way of handling dynamic memory allocation. uC/OS-II provides alternatives to malloc () and free () and freeRTOS provides three ways of handling this. First one simply allows you to allocate memory but not freeing them up. Second way is we can allocate and free but in fixed size block and not in random size. Third one just provides the wrapper functions to the memory allocation functions which are same as implemented for no OS case.

I am not much familiar with RTOSes so I am not sure whether all the supported RTOS provide their own alternatives to allocation functions. If they do, we can skip these functions while building library for these OS. 
 
Can anyone provide me with the pointers for further information on dynamic memory allocation in case of RTOS or should I first work on the implementation of allocation functions for no OS and Linux only and we can add support for RTOS afterwards.

Regards,
Praveen Kaushik