void ss_active_add(SuperSlab* ss, uint32_t n) {
    atomic_fetch_add_explicit(&ss->total_active_blocks, n, memory_order_relaxed);
}
static inline __attribute__((always_inline)) void ss_active_inc(SuperSlab* ss) {
    atomic_fetch_add_explicit(&ss->total_active_blocks, 1u, memory_order_relaxed);
}