Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx> wrote: > Assume the time source is a global clock which insures that time will never > *ever* go backward. Use a smp_rmb() to make sure the cnt_lo value is read before > __m_cnt_hi. If you have an smp_rmb(), then don't you need an smp_wmb()/smp_mb() to match it to make it work? And is your assumption valid that smp_rmb() will affect memory vs the I/O access to read the clock? There's no requirement that cnt_lo will have been read from an MMIO location at all. David -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
