On Sun, 2005-03-13 at 09:35 +0000, Hugh Dickins wrote: > On Sun, 13 Mar 2005, Arjan van de Ven wrote: > > > \ > > > + if ((lock)->break_lock) \ > > > + (lock)->break_lock = 0; \ > > > } > > > \ > > if it really worth an conditional there? the cacheline of the lock is > > made dirty anyway on unlock, so writing an extra 0 is like almost free > > (maybe half a cycle) while a conditional jump can be 100+.... > > I wondered the same, I don't know and would defer to those who do: > really I was just following the style of where break_lock is set above, > which follows soon (unless preempted) after a _raw_whatever_trylock.
if the cacheline is dirtied previously it's just free to do the write so I suggest to remove the conditional... - 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/