From 4f911b0daf0f7028a4fe792b701a48d10da36d84 Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Mon, 16 Nov 2009 10:34:15 +0100 Subject: microblaze: ftrace: Add dynamic function graph tracer This patch add support for dynamic function graph tracer. There is one my expactation that I can do flush_icache after all code modification. On microblaze is this safer than do flush for every entry. For icache is used name flush but correct should be invalidation - this will be fix in upcomming new cache implementaion and WB support. Signed-off-by: Michal Simek --- arch/microblaze/kernel/ftrace.c | 28 ++++++++++++++++++++++++++++ arch/microblaze/kernel/mcount.S | 6 ++++++ 2 files changed, 34 insertions(+) (limited to 'arch/microblaze/kernel') diff --git a/arch/microblaze/kernel/ftrace.c b/arch/microblaze/kernel/ftrace.c index 0952a8b52c35..388b31ca65a1 100644 --- a/arch/microblaze/kernel/ftrace.c +++ b/arch/microblaze/kernel/ftrace.c @@ -206,4 +206,32 @@ int ftrace_update_ftrace_func(ftrace_func_t func) return ret; } +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +unsigned int old_jump; /* saving place for jump instruction */ + +int ftrace_enable_ftrace_graph_caller(void) +{ + unsigned int ret; + unsigned long ip = (unsigned long)(&ftrace_call_graph); + + old_jump = *(unsigned int *)ip; /* save jump over instruction */ + ret = ftrace_modify_code(ip, MICROBLAZE_NOP); + flush_icache(); + + pr_debug("%s: Replace instruction: 0x%x\n", __func__, old_jump); + return ret; +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + unsigned int ret; + unsigned long ip = (unsigned long)(&ftrace_call_graph); + + ret = ftrace_modify_code(ip, old_jump); + flush_icache(); + + pr_debug("%s\n", __func__); + return ret; +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ #endif /* CONFIG_DYNAMIC_FTRACE */ diff --git a/arch/microblaze/kernel/mcount.S b/arch/microblaze/kernel/mcount.S index 84a19458c74d..e7eaa7a8cbd3 100644 --- a/arch/microblaze/kernel/mcount.S +++ b/arch/microblaze/kernel/mcount.S @@ -97,6 +97,7 @@ ENTRY(ftrace_caller) nop; /* MS: HAVE_FUNCTION_TRACE_MCOUNT_TEST end of checking */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER +#ifndef CONFIG_DYNAMIC_FTRACE lwi r5, r0, ftrace_graph_return; addik r6, r0, ftrace_stub; /* asm implementation */ cmpu r5, r5, r6; /* ftrace_graph_return != ftrace_stub */ @@ -108,6 +109,11 @@ ENTRY(ftrace_caller) cmpu r5, r5, r6; /* ftrace_graph_entry != ftrace_graph_entry_stub */ beqid r5, end_graph_tracer; nop; +#else /* CONFIG_DYNAMIC_FTRACE */ +NOALIGN_ENTRY(ftrace_call_graph) + /* MS: jump over graph function - replaced from C code */ + bri end_graph_tracer +#endif /* CONFIG_DYNAMIC_FTRACE */ addik r5, r1, 120; /* MS: load parent addr */ addik r6, r15, 0; /* MS: load current function addr */ bralid r15, prepare_ftrace_return; -- cgit v1.2.3