From a1cf53ac6d156721afa86453d5e8423461881231 Mon Sep 17 00:00:00 2001 From: Joel Fernandes Date: Thu, 20 Oct 2016 00:34:04 -0700 Subject: ramoops: Split ftrace buffer space into per-CPU zones If the RAMOOPS_FLAG_FTRACE_PER_CPU flag is passed to ramoops pdata, split the ftrace space into multiple zones depending on the number of CPUs. This speeds up the performance of function tracing by about 280% in my tests as we avoid the locking. The trade off being lesser space available per CPU. Let the ramoops user decide which option they want based on pdata flag. Signed-off-by: Joel Fernandes [kees: added max_ftrace_cnt to track size, added DT logic and docs] Signed-off-by: Kees Cook --- Documentation/devicetree/bindings/reserved-memory/ramoops.txt | 3 +++ 1 file changed, 3 insertions(+) (limited to 'Documentation/devicetree/bindings/reserved-memory') diff --git a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt index e81f821a2135..0eba562fe5c6 100644 --- a/Documentation/devicetree/bindings/reserved-memory/ramoops.txt +++ b/Documentation/devicetree/bindings/reserved-memory/ramoops.txt @@ -46,3 +46,6 @@ Optional properties: (defaults to buffered mappings) - no-dump-oops: if present, only dump panics (defaults to panics and oops) + +- flags: if present, pass ramoops behavioral flags (defaults to 0, + see include/linux/pstore_ram.h RAMOOPS_FLAG_* for flag values). -- cgit v1.2.3