[UNIKRAFT PATCH v5 0/5] Memory Pools

[Simon Kuenzer <simon.kuenzer@xxxxxxxxx>]

This series implements a memory pool allocator. Pool objects have the same
size and are pre-allocated. Due to this simplification allocations and free
operations are as cheap as O(1). Its intended use is performance critical
allocations when allocation sizes do not vary, like network stacks or disk
buffer caches.

Changes since v4:
 - Fix interface descriptions in headers
 - Add a crash (UK_CRASH) as current workaround when free'ing a
   ukallocpool with `ukalloc` interface. The reason is that
   unregistering from ukalloc is not yet supported. Having a pool
   still registered to `ukalloc` although being freed will cause to
   use-after-free bugs.

 - Make each patch individually compile'able: There was an incorrect
   patch split introduced with v4

Changes since v3:
 - Remove functionality to let initialize objects by the pool.
   This should be implemented with a wrapping function instead and
   maybe less confusing when using the pool with the uk_alloc API.
 - Provide `uk_allocpool_objlen()`
 - Fix `uk_allocpool2ukalloc()`, the interface was not exported properly

Changes since v2:
 - Fix compile error when `CONFIG_LIBUKALLOC_IFSTATS` is activated

Changes since v1:
 - Correct license header in `pool.c`

Simon Kuenzer (5):
  lib/ukallocpool: Library skeleton
  lib/ukallocpool: LIFO pool implementation
  lib/ukallocpool: Allocate pool on parent allocator
  lib/ukallocpool: `lib/ukalloc` compatible interface
  lib/ukallocpool: Batched allocation

 lib/Makefile.uk                        |   1 +
 lib/ukallocpool/Config.uk              |   6 +
 lib/ukallocpool/Makefile.uk            |   6 +
 lib/ukallocpool/exportsyms.uk          |  11 +
 lib/ukallocpool/include/uk/allocpool.h | 206 ++++++++++++++
 lib/ukallocpool/pool.c                 | 354 +++++++++++++++++++++++++
 6 files changed, 584 insertions(+)
 create mode 100644 lib/ukallocpool/Config.uk
 create mode 100644 lib/ukallocpool/Makefile.uk
 create mode 100644 lib/ukallocpool/exportsyms.uk
 create mode 100644 lib/ukallocpool/include/uk/allocpool.h
 create mode 100644 lib/ukallocpool/pool.c

-- 
2.20.1