* Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > yes and i gave in - Nick and Jens wants to do some crazy stuff and > > they had the numbers. Here's the previous discussion: > > > > http://lkml.org/lkml/2008/2/27/125 > > No, the previous discussion was about single *queues* vs single > *vectors*. > > I agree unconditionally with the decision to use a separate per-cpu > queue from the shared queue (in fact, I would argue that the "mask" > code might want to notice when the mask is just a single CPU, and turn > a mask request into a targeted request). > > But I wonder why we want to then have two IPI target vectors, when it > would appear to be perfectly fine and cheap to have just a single > vector that can handle both the per-cpu case and the shared queue case > (since the thing would tend to be one or the other, not both). > > A single vector is still pefectly fine, if 99% of all usage cases are > the targeted-to-a-single-cpu thing, because the shared queue will > basically be empty (and you can test that without even taking any > locks). ok. In which case the reschedule vector could be consolidated into that as well (it's just a special single-CPU call). Then there would be no new vector allocations needed at all, just the renaming of RESCHEDULE_VECTOR to something more generic. Ingo -- 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