On Wed, 7 Jan 2009, Linus Torvalds wrote: > > > > "Is get_task_struct() really that bad?" > > Yes. It's an atomic access (two, in fact, since you need to release it > too), which is a huge deal if we're talking about a timing-critical > section of code. There's another issue: you also need to lock the thing that gives you the task pointer in the first place. So it's not sufficient to do get_task_struct(), you also need to do it within a context where you know that the pointer is not going away _while_ you do it. And with the mutexes clearing the ->owner field without even holding the spinlock, that is not a guarantee we can easily get any way. Maybe we'd need to hold the tasklist_lock or something. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
