On Mon, May 16, 2016 at 03:02:13PM +0800, Li Zhong wrote: > It seems that we don't need to take the lock before evaluating irq's > resend flag. What needed is to make sure when we clear the ics's bit > in the icp's resend_map, we don't miss the resend flag of the irqs > that set the bit. > > And seems this could be ordered through the barrier in test_and_clear_bit(), > and an newly added wmb when setting irq's resend flag, and icp's resend_map.
This looks fine to me. Is there a measurable performance improvement from this? I understand it could be hard to measure. Also, you could make the patch description more definite - just say that we don't need to take the lock, there's no need for "seems". Paul. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
