x86, bts, ftrace: a BTS ftrace plug-in prototype
Impact: add new ftrace plugin
A prototype for a BTS ftrace plug-in.
The tracer collects branch trace in a cyclic buffer for each cpu.
The tracer is not configurable and the trace for each snapshot is
appended when doing cat /debug/tracing/trace.
This is a proof of concept that will be extended with future patches
to become a (hopefully) useful tool.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index b815664..85a7857 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -515,6 +515,7 @@
config X86_DS
def_bool X86_PTRACE_BTS
depends on X86_DEBUGCTLMSR
+ select HAVE_HW_BRANCH_TRACER
config X86_PTRACE_BTS
bool "Branch Trace Store"