common: introduce malloc/free implementation

The new code allows to replace the existing one buffer at a time
shared memory facility with a malloc/free implementation. A new
configuration option is being provided (CONFIG_MALLOC).

The names of functions allocating and freeing memory are not being
changed to allow to switch between the two implementations seamlessly.

A double linked list of buffers is used to keep track of free and
allocated memory. During initialization the entire free memory block
is considered a single free buffer. No allocations/frees are allowed
from within interrupts. The control structures are protected by a
semaphore, so allocate and free invocation could be blocking.

A test is added which randomly allocates and frees memory, continuing
until all branches in the allocate and free functions are taken.

BUG=chrome-os-partner:
TEST=make buildall -j succeeds, which includes testing the new
     malloc/free implementation.

Change-Id: I5e71c0190c6c247ec73bb459f66a6d7a06e3d248
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/420466
Reviewed-by: Randall Spangler <rspangler@chromium.org>

0 files changed, 0 insertions, 0 deletions