From 1026ff9b8e6cbb112fd708b2e62f1812ce9a4e01 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Fri, 11 Jul 2014 23:23:53 -0400 Subject: [PATCH] ftrace/x86: Have function graph tracer use its own trampoline The function graph trampoline is called from the function trampoline and both do a save and restore of registers. The save of registers done by the function trampoline when only the function graph tracer is running is a waste of CPU cycles. As the function graph tracer trampoline in x86 is dependent from the function trampoline, we can call it directly when a function is only being traced by the function graph trampoline. Acked-by: H. Peter Anvin Signed-off-by: Steven Rostedt --- arch/x86/include/asm/ftrace.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 0525a8bdf65d..e1f7fecaa7d6 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -68,6 +68,8 @@ struct dyn_arch_ftrace { int ftrace_int3_handler(struct pt_regs *regs); +#define FTRACE_GRAPH_TRAMP_ADDR FTRACE_GRAPH_ADDR + #endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* __ASSEMBLY__ */ #endif /* CONFIG_FUNCTION_TRACER */ -- 2.34.1