On Thu, 11 Dec 2008 20:28:00 +0000 Al Viro <v...@zeniv.linux.org.uk> wrote:
> On Thu, Dec 11, 2008 at 12:16:35PM -0800, Andrew Morton wrote: > > > +#if (8 * THREAD_SIZE) > PAGE_SIZE > > > max_threads = mempages / (8 * THREAD_SIZE / PAGE_SIZE); > > > +#else > > > + max_threads = mempages * (PAGE_SIZE / (8 * THREAD_SIZE)); > > > +#endif > > > > The expression you've chosen here can be quite inacccurate, because > > ((PAGE_SIZE / (8 * THREAD_SIZE)) is a small number. The way to > > preserve accuracy is > > > > max_threads = (mempages * PAGE_SIZE) / (8 * THREAD_SIZE); > > > > so how about avoiding the nasty ifdefs and doing > > Are you sure? No, not at all. It's all too hard. Which is why I'm looking for simplification. > Do they actually cross the page boundaries? Some flavours of slab have at times done an order-1 allocation for objects which would fit into an order-0 page (etc) if it looks like that will be beneficial from a packing POV. I'm unsure whether that still happens - I tried to get it stamped out for reliability reasons. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
