On Fri, Apr 18, 2008 at 4:46 AM, pradeep singh rautela <rautelap@xxxxxxxxx> wrote: > > On Fri, Apr 18, 2008 at 10:13 AM, Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote: > > + /* How many pages will this take? */ > > + npages = 1 + (base + len - 1)/PAGE_SIZE - base/PAGE_SIZE; > > Hi Rusty, > A trivial suggestion, how about > npages = 1+(len -1)/PAGE_SIZE ? That's not the same. In particular, his version accounts for the fractional page at the beginning, while yours doesn't. While it's tempting to use algebra to simplify things, it's not safe to do so when the expression involves division over the integers. The only care-free integer math in a computer is subtraction and ++. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization
