From 819e50e25d0ce8a75f5cba815416a6a8573655c4 Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Wed, 30 Apr 2014 18:54:33 +0900 Subject: arm64: Add ftrace support This patch implements arm64 specific part to support function tracers, such as function (CONFIG_FUNCTION_TRACER), function_graph (CONFIG_FUNCTION_GRAPH_TRACER) and function profiler (CONFIG_FUNCTION_PROFILER). With 'function' tracer, all the functions in the kernel are traced with timestamps in ${sysfs}/tracing/trace. If function_graph tracer is specified, call graph is generated. The kernel must be compiled with -pg option so that _mcount() is inserted at the beginning of functions. This function is called on every function's entry as long as tracing is enabled. In addition, function_graph tracer also needs to be able to probe function's exit. ftrace_graph_caller() & return_to_handler do this by faking link register's value to intercept function's return path. More details on architecture specific requirements are described in Documentation/trace/ftrace-design.txt. Reviewed-by: Ganapatrao Kulkarni Acked-by: Will Deacon Signed-off-by: AKASHI Takahiro Signed-off-by: Will Deacon --- arch/arm64/Kconfig | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm64/Kconfig') diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c7022a9d5eeb..8a25a4ad3159 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -38,6 +38,8 @@ config ARM64 select HAVE_DMA_CONTIGUOUS select HAVE_EFFICIENT_UNALIGNED_ACCESS select HAVE_FTRACE_MCOUNT_RECORD + select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GENERIC_DMA_COHERENT select HAVE_HW_BREAKPOINT if PERF_EVENTS select HAVE_MEMBLOCK -- cgit v1.2.3