RFC Support externally allocated memory in DPDK

This is a proposal to enable using externally allocated memory in DPDK.

In a nutshell, here is what is being done here:

- Index malloc heaps by NUMA node index, rather than NUMA node itself
- Add identifier string to malloc heap, to uniquely identify it
- Allow creating named heaps and add/remove memory to/from those heaps
- Allocate memseg lists at runtime, to keep track of IOVA addresses of externally allocated memory
- If IOVA addresses aren't provided, use RTE_BAD_IOVA
- Allow malloc and memzones to allocate from named heaps

The responsibility to ensure memory is accessible before using it is on the shoulders of the user - there is no checking done with regards to validity of the memory (nor could there be...).

The following limitations are present:

- No multiprocess support
- No thread safety

There is currently no way to allocate memory during initialization stage, so even if multiprocess support is added, it is not guaranteed to work because of underlying issues with mapping fbarrays in secondary processes. This is not an issue in single process scenario, but it may be an issue in a multiprocess scenario in case where primary doesn't intend to share the externally allocated memory, yet adding such memory could fail because some other process failed to attach to this shared memory when it wasn't needed.

Anatoly Burakov (11):
mem: allow memseg lists to be marked as external
eal: add function to rerieve socket index by socket ID
malloc: index heaps using heap ID rather than NUMA node
malloc: add name to malloc heaps
malloc: enable retrieving statistics from named heaps
malloc: enable allocating from named heaps
malloc: enable creating new malloc heaps
malloc: allow adding memory to named heaps
malloc: allow removing memory from named heaps
malloc: allow destroying heaps
memzone: enable reserving memory from named heaps

 config/common_base                            |   1 +
 lib/librte_eal/common/eal_common_lcore.c      |  15 +
 lib/librte_eal/common/eal_common_memory.c     |  51 +++-
 lib/librte_eal/common/eal_common_memzone.c    | 283 ++++++++++++++----
 .../common/include/rte_eal_memconfig.h        |   5 +-
 lib/librte_eal/common/include/rte_lcore.h     |  19 +-
 lib/librte_eal/common/include/rte_malloc.h    | 158 +++++++++-
 .../common/include/rte_malloc_heap.h          |   2 +
 lib/librte_eal/common/include/rte_memzone.h   | 183 +++++++++++
 lib/librte_eal/common/malloc_heap.c           | 277 +++++++++++++++--
 lib/librte_eal/common/malloc_heap.h           |  26 ++
 lib/librte_eal/common/rte_malloc.c            | 197 +++++++++++-
 lib/librte_eal/rte_eal_version.map            |  10 +
 13 files changed, 1118 insertions(+), 109 deletions(-)

2.17.1