> +/** > + * Pre-reserve backing memory. > + * > + * Ensures that at least @p size bytes of memzone-backed memory are > + * available to the allocator on @p socket_id, reserving additional > + * memzones from EAL as needed to reach that total. Subsequent > + * allocations served from the pre-reserved memory do not incur > + * memzone-reservation cost. > + * > + * The reservation is cumulative: repeated calls to > + * rte_fastmem_reserve() with the same @p socket_id grow the > + * reservation monotonically. Reserved memory is never returned to > + * the system during the allocator's lifetime. > + * > + * A typical use is to call rte_fastmem_reserve() once at > + * application startup, with a size chosen to cover the expected > + * steady-state working set. Allocations and frees during > + * steady-state operation then avoid memzone reservations entirely. > + * > + * @param size > + * The minimum amount of backing memory, in bytes, to make > + * available on @p socket_id. The allocator may reserve more than > + * the requested amount due to internal rounding (e.g., to memzone > + * or block granularity). > + * > + * @param socket_id > + * The NUMA socket on which to reserve memory, or SOCKET_ID_ANY > + * to leave the choice to the allocator. With SOCKET_ID_ANY, the > + * allocator starts on the calling lcore's socket (or the first > + * configured socket if the caller is not bound to one) and falls > + * back to other sockets if the preferred socket cannot satisfy > + * the reservation. > + * > + * @return > + * - 0: Success. > + * - -ENOMEM: Insufficient huge-page memory to satisfy the request. > + * - -EINVAL: Invalid @p socket_id. > + */ > +__rte_experimental > +int > +rte_fastmem_reserve(size_t size, int socket_id);
@Bruce, I vaguely recall that we discussed something about busses and sockets a long time ago, but I cannot remember the details. Is socket_id the right type (and parameter name) to identify a memory bus? @Vipin, You have been working on topology awareness. Same question to you: Is socket_id the right type (and parameter name) to identify a memory bus?
