On 08/20, Peter Zijlstra wrote: > > On Mon, 2012-08-20 at 17:05 +0200, Oleg Nesterov wrote: > > > > Yes, we can add the explicit argument to __task_work_run(), but it can > > check PF_EXITING instead, this looks simpler to me. > > I guess we could.. but I thought the explicit callback was simpler ;-)
I won't insist. The patch I sent uses PF_EXITING and the fake "struct callback_head* TWORK_EXITED", but this looks almost the same. > > Note also your patch breaks fifo, but this is fixable. > > Why do you care about the order? IMHO, this is just more natural. For example. keyctl_session_to_parent() does _cancel only to protect from exploits doing keyctl(KEYCTL_SESSION_TO_PARENT) in an endless loop. It could simply do task_work_add(), but in this case we need fifo for correctness. > Iterating a single linked queue in fifo > seems more expensive than useful. Currently the list is fifo (we add to the last element), this is O(1). But the list should be short, we can reverse it in _run() if we change task_work_add() to add to the head. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
