* Tejun Heo (tj@xxxxxxxxxx) wrote: > On Mon, Oct 29, 2012 at 11:58:14AM -0700, Tejun Heo wrote: > > On Mon, Oct 29, 2012 at 02:53:19PM -0400, Mathieu Desnoyers wrote: > > > The argument about hash_init being useful to add magic values in the > > > future only works for the cases where a hash table is declared with > > > DECLARE_HASHTABLE(). It's completely pointless with DEFINE_HASHTABLE(), > > > because we could initialize any debugging variables from within > > > DEFINE_HASHTABLE(). > > > > You can do that with [0 .. HASH_SIZE - 1] initializer. > > And in general, let's please try not to do optimizations which are > pointless. Just stick to the usual semantics. You have an abstract > data structure - invoke the initializer before using it. Sure, > optimize it if it shows up somewhere. And here, if we do the > initializers properly, it shouldn't cause any more actual overhead - > ie. DEFINE_HASHTABLE() will basicallly boil down to all zero > assignments and the compiler will put the whole thing in .bss anyway. Yes, agreed. I was going too far in optimization land by proposing assumptions on zeroed memory. All I actually really care about is that we don't end up calling hash_init() on a statically defined (and thus already initialized) hash table. Thanks, Mathieu -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>