On Mon, Jun 11, 2007 at 06:55:46PM -0700, Arjan van de Ven wrote: > Andrew Morton wrote: > >On Mon, 11 Jun 2007 18:10:40 -0700 Arjan van de Ven > ><[EMAIL PROTECTED]> wrote: > > > >>Andrew Morton wrote: > >>>>Where as resource pool is exactly opposite of mempool, where each > >>>>time it looks for an object in the pool and if it exist then we > >>>>return that object else we try to get the memory for OS while > >>>>scheduling the work to grow the pool objects. In fact, the work > >>>>is schedule to grow the pool when the low threshold point is hit. > >>>I realise all that. But I'd have thought that the mempool approach is > >>>actually better: use the page allocator and only deplete your reserve > >>>pool > >>>when the page allocator fails. > >>the problem with that is that if anything downstream from the iommu > >>layer ALSO needs memory, we've now eaten up the last free page and > >>things go splat. > > > >If that happens, we still have the mempool reserve to fall back to. > > we do, except that we just ate the memory the downstream code would > use and get ... so THAT can't get any.
Then the downstream ought to be using a mempool? -- Mathematics is the supreme nostalgia of our time. - 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/
