Peter, Here's a really trivial patch that touches arch/x86/include/asm/ftrace.h
Can you ack it. Thanks. This is based on the patches here: http://marc.info/?l=linux-kernel&m=140513619913439&w=2 Thanks, -- Steve >From 32443f104c172cc368882101cd65604dc046f099 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" <rost...@goodmis.org> 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. Cc: "H. Peter Anvin" <h...@zytor.com> Signed-off-by: Steven Rostedt <rost...@goodmis.org> --- 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 0525a8b..e1f7fec 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 */ -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
