zswap: export more zswap store failure stats

Since commit 42c06a0e ("mm: kill frontswap") we no longer have a
counter to tracks the number of zswap store failures.  This makes it hard
to investigate and monitor for zswap issues.

This patch adds a global and a per-cgroup zswap store failure counter,
as well as a dedicated debugfs counter for compression algorithm failure
(which can happen for e.g when random data are passed to zswap).

Link: https://lkml.kernel.org/r/20231024000702.1387130-1-nphamcs@gmail.com


Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>