Can you explain this a bit more?
>+ /*
>+ * Be sure that the CPU doesn' t reorder instructions.
>+ * I am not sure if it' s needed also before an outb().
>+ * If not tell me ;-). -arca
>+ */
>+ mb();
An mb() stops the *compiler* from re-ordering things. It doesn't generate any
actual code and so the CPU never sees it. I'm fairly sure that inb() and
outb() are volatile themselves and don't need additional optimisation barriers.
Did adding this mb() fix a problem?
p.
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