zswap is a thin compression backend for frontswap. It receives pages from
frontswap and attempts to store them in a compressed memory pool, resulting in
an effective partial memory reclaim and dramatically reduced swap device I/O.
Additionally, in most cases, pages can be retrieved from this compressed store
much more quickly than reading from tradition swap devices resulting in faster
performance for many workloads.
It also has support for evicting swap pages that are currently compressed in
zswap to the swap device on an LRU(ish) basis. This functionality is very
important and make zswap a true cache in that, once the cache is full or can't
grow due to memory pressure, the oldest pages can be moved out of zswap to the
swap device so newer pages can be compressed and stored in zswap.
This patch adds the zswap driver to mm/
Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx>