From: Keller, Jacob E > Sent: 14 August 2017 23:11 > > From: David Miller [mailto:da...@davemloft.net] > > Sent: Saturday, August 12, 2017 1:04 PM > > From: Jeff Kirsher <jeffrey.t.kirs...@intel.com> > > Date: Sat, 12 Aug 2017 04:08:41 -0700 > > > > > Also ensure that the flags variable is actually a u64 to guarantee > > > 64bits of space on all architectures. > > > > Why? You don't need 64-bits, you only need 27. > > > > This will be unnecessarily expensive on 32-bit platforms. > > > > Please don't do this. > > I suppose a better method would be to switch to using a declare_bitmap > instead, so that it > automatically sizes based on the number of flags we have. The reason we chose > 64bits is because we > will add flags in the future, as we originally had more than 32 flags prior > to this patch until we > moved some into a separate field. > > But now that I think about it, using DECLARE_BITMAP makes more sense, though > it's a bit more invasive > of the code.
And horribly stupid unless you really need dynamic indexes. David