On 08/11/2012 11:43, "Ian Campbell" <i...@hellion.org.uk> wrote:
>>> I'll leave this to Keir (who wrote the debugging patch) to answer but it >>> looks to me like it should be useful! >> >> I'm scratching my head. plt_wrap is earlier than plt_now, which should be >> impossible. > > impossible due to guarantees made by the h/w or by construction in Xen. That's a question, right? By construction in Xen. > There appears to be a certain amount of hardware-specificness to the > issue -- so I'm wondering if maybe there are some platforms whose tsc is > not as monotonically increasing as it needs to be... plt_* timestamps are not derived from TSC at all. >> plt_stamp64 oddly has low 32 bits identical to new_stamp. That >> seems very very improbable! > > Does this code run on all cpus or just one? Is it always the same one? Always cpu0. -- Keir -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/ccc15bf9.51b87%k...@xen.org