percpu: expose statistics about percpu memory via debugfs
There is limited visibility into the use of percpu memory leaving us
unable to reason about correctness of parameters and overall use of
percpu memory. These counters and statistics aim to help understand
basic statistics about percpu memory such as number of allocations over
the lifetime, allocation sizes, and fragmentation.
New Config: PERCPU_STATS
Signed-off-by: Dennis Zhou <dennisz@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/mm/Kconfig b/mm/Kconfig
index beb7a45..8fae426 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -706,3 +706,11 @@
bool
config ARCH_HAS_PKEYS
bool
+
+config PERCPU_STATS
+ bool "Collect percpu memory statistics"
+ default n
+ help
+ This feature collects and exposes statistics via debugfs. The
+ information includes global and per chunk statistics, which can
+ be used to help understand percpu memory usage.