On Mon, Oct 29, 2012 at 5:42 AM, Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> wrote: > > So defining e.g.: > > #include <linux/log2.h> > > #define DFR_HASH_BITS (PAGE_SHIFT - ilog2(BITS_PER_LONG)) > > would keep the intended behavior in all cases: use one page for the hash > array. Well, since that wasn't true before either because of the long-time bug you point out, clearly the page size isn't all that important. I think it's more important to have small and simple code, and "9" is certainly that, compared to playing ilog2 games with not-so-obvious things. Because there's no reason to believe that '9' is in any way a worse random number than something page-shift-related, is there? And getting away from *previous* overly-complicated size calculations that had been broken because they were too complicated and random, sounds like a good idea. Linus -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel