[Minios-devel] [UNIKRAFT PATCH v7 0/5] add support for generic memory allocators

[Hugo Lefeuvre <hugo.lefeuvre@xxxxxxxxx>]

This patch series addresses a few bugs and design issues in ukalloc in
order to ease the port of new allocators to unikraft.

"lib/ukalloc: cleanup page allocation interface" and "lib/ukalloc: change
page allocation api to take a number of pages" both clean up the memory
allocation api, removing unused macros, undefined functions and modifying
the palloc and pfree api to take as parameter a number of pages instead of
an order.

"lib/ukalloc: implement new allocator helpers" implements new helpers for
generic, malloc based memory allocators.

Unfortunately, using this patch with a generic allocator results in page
fault during uk_thread_current because the stack is not aligned at
STACK_SIZE.

This is because the stack is allocated via palloc and not posix_memalign,
hence only guaranteeing page alignment.

We address this issue in "lib/uksched: use posix_memalign to allocate
stack" and "lib/ukalloc: fix multiple issues in uk_posix_memalign_ifpages"
which adds support for alignment > page size to uk_posix_memalign_ifpages.

This patch also addresses an out-of-bounds issue in
uk_posix_memalign_ifpages with allocation aligned at less than a page.

Changes v7:
 - fix style issues reported by checkpatch
 - update a few comments for clarity
 - fix typos in commit messages
 - in "lib/ukalloc: fix multiple issues in uk_posix_memalign_ifpages":
   check for ptr >= __PAGE_SIZE + sizeof(struct metadata_ifpages) instead
   of ptr > __PAGE_SIZE (see comments).
 - change uk_alloc_init_malloc to rather be a helper that initializes the
   struct for allocators that just don't support palloc() and pfree().

Hugo Lefeuvre (5):
  lib/ukalloc: cleanup page allocation interface
  lib/ukalloc: change page allocation api to take a number of pages
  lib/ukalloc: fix multiple issues in uk_posix_memalign_ifpages
  lib/uksched: use posix_memalign to allocate stack
  lib/ukalloc: implement new allocator helpers

 lib/ukalloc/Config.uk               |   6 --
 lib/ukalloc/alloc.c                 | 199 ++++++++++++++++++++++++------------
 lib/ukalloc/exportsyms.uk           |   3 +
 lib/ukalloc/include/uk/alloc.h      |  46 ++++-----
 lib/ukalloc/include/uk/alloc_impl.h |  32 ++++--
 lib/ukallocbbuddy/Config.uk         |   1 -
 lib/ukallocbbuddy/bbuddy.c          |  26 ++++-
 lib/uksched/sched.c                 |   4 +-
 plat/xen/drivers/9p/9pfront.c       |  14 +--
 plat/xen/drivers/blk/blkfront.c     |   4 +-
 plat/xen/gnttab.c                   |   2 +-
 plat/xen/x86/mm.c                   |  10 +-
 12 files changed, 224 insertions(+), 123 deletions(-)

-- 
2.7.4


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