On Tue, 16 Jan 2018, Matthew Wilcox wrote: > > Sure this data is never changed. It can be const. > > It's changed at initialisation. Look: > > kmem_cache_create(const char *name, size_t size, size_t align, > slab_flags_t flags, void (*ctor)(void *)) > s = create_cache(cache_name, size, size, > calculate_alignment(flags, align, size), > flags, ctor, NULL, NULL); > > The 'align' that ends up in s->align, is not the user-specified align. > It's also dependent on runtime information (cache_line_size()), so it > can't be calculated at compile time. Then we would need another align field in struct kmem_cache that takes the changes value? > 'flags' also gets mangled: > flags &= CACHE_CREATE_MASK; Well ok then that also belongs into kmem_cache and the original value stays in kmem_cache_attr. > unsigned int would be my preference. Great.
