At 05:18 07-08-2006, you wrote:
Greetings all,
I have been looking at using both cores on PortalPlayer based devices
(iPod, Sansa E200, iRiver H10.)
I think that supporting this is going to require changes to the threading
API so that threads can be run on both cores.
I propose:
1. Changing the variables in thread.c such as num_threads to be arrays
...
3. Changing the existing create/remove_thread to be:
int create_thread(void (*function)(void), void* stack, int stack_size,
const char *name)
{
return create_thread_on_core(CURRENT_CORE, function, stack, stack_size,
name);
}
void remove_thread(int threadnum)
{
remove_thread_from_core(CURRENT_CORE, threadnum);
}
CURRENT_CORE would be the core that the thread is being created from.
This would mean that the only code changes necessary outside of thread.c
would be in the debug menu.
Excuse me, but I've got two daft newbie-type questions here that are
more for my own education than anything else.
Firstly, might it be better to declare create_thread and
remove_thread using #define directives and removing the existing
functional definitions instead of using the suggested changes to the
existing implementations? This would eliminate an extra function
call. Oh, but maybe create_thread and remove_thread are not called
that often so perhaps speed isn't a concern here. Can anyone put me straight?
Secondly, could it also be useful to have a function or #define that
reports how many cores there are on the existing platform? That way,
it wouldn't be necessary to check for specific players and/or models
when deciding whether to start a thread on a second core.
Cheers,
Andrew.
