On Mon, Jul 13, 2020 at 05:15:39PM +0100, Chris Down wrote: > +#define SHMEM_INO_BATCH 1024U ... > + if (unlikely((ino & ~SHMEM_INO_BATCH) == 0)) { I don't think that works. I think you meant to write ~(SHMEM_INO_BATCH - 1). Or just ino % SHMEM_INO_BATCH which works even for non-power-of-two.