[coreboot] Fw:Re: I want to submit some code, but there aresomeproblems.

[王翔]

> Oh! SMP_PAUSE actually jumps here! I would *not* expect that, when I
> read code like this:
>
	> SMP_PAUSE(active);
	> foo();
	> bar(42);
	> SMP_RESUME();
>
> Something like the following would be a lot clearer for me:
>
	> if (mhartid() == active) {
		> foo();
> bar(42);
	> }
> 
> Or maybe:
>
	> if (running_on_hart(active)) { ... }
>
> But note that this lacks the barriers/locking that your code has.
>
> Jonathan Neuschäfer


```
if (running_on_hart(active)) { ... }
```
Yes, these codes are clearer.

/*
 * If your code needs to temporarily block multiple-threads, do this:
 *     SMP_PAUSE(active)    // `active` is hartid of working thread
 *     ... single-threaded work ...
 *     SMP_RESUME()
 *     ... multi-threaded work ...
 */
But sometimes multi-threaded work has to wait for the single-threaded work to complete.

etc:
    single-threaded work : init ddr controller
    multi-threaded work  : some operations related to memory

It is necessary to wait for the completion of single-threaded work.

Xiang Wang
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