[ECOS] Memory Map Urgent!

John Carter john.carter@tait.co.nz
Wed Dec 8 00:14:00 GMT 2004

On Tue, 7 Dec 2004, Ruchika Singh wrote:

> I had a doubt regarding memory map for threads. Where does the initialized/
> uninitialized data or dynamic data associated with threads ( created using
> cyg_thread_create) end up. What i mean to ask is that are there separate
> rodata, bss, .data sections for threads or are they interleaved with those of
> ecos sections itself.

Wouldn't quite say interleaved. Probably more in whatever order that the 
the corresponding .o and .a files get presented to the linker. (But don't 
ever rely on such an ordering, it may depend on platform / linker version 

> If I create a object using malloc call in a thread A, where is this object
> likely to be placed. Or is it that any data associated with thread will end up
> in its associated stack??

Only automatic variables declared down the call tree from the thread entry 
point end up on the stack.

Malloc places things between __heap1 symbol at the end of the .bss/.data 
segments and the end of the ram region. This is shared between threads.

You can configure eCos to have some per thread data space.

John Carter                             Phone : (64)(3) 358 6639
Tait Electronics                        Fax   : (64)(3) 359 4632
PO Box 1645 Christchurch                Email : john.carter@tait.co.nz
New Zealand

The universe is absolutely plastered with the dashed lines exactly one
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