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| author | Zong Li <zong@andestech.com> | 2018-08-15 11:01:10 +0800 |
|---|---|---|
| committer | Greentime Hu <greentime@andestech.com> | 2018-09-04 14:45:18 +0800 |
| commit | 95cd2f7bce9aa712473bba1b5b3f4fdec148baee (patch) | |
| tree | db22541157723489503379d7cede8df84c58b0d7 /arch/nds32 | |
| parent | 6b1d6d2fba37129f690ee7e9164f225c55626cac (diff) | |
| download | linux-0-day-95cd2f7bce9aa712473bba1b5b3f4fdec148baee.tar.gz linux-0-day-95cd2f7bce9aa712473bba1b5b3f4fdec148baee.tar.xz | |
nds32/ftrace: Support dynamic function graph tracer
This patch contains the implementation of dynamic function graph tracer.
Signed-off-by: Zong Li <zong@andestech.com>
Acked-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Diffstat (limited to 'arch/nds32')
| -rw-r--r-- | arch/nds32/kernel/ftrace.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/arch/nds32/kernel/ftrace.c b/arch/nds32/kernel/ftrace.c index 3ca676b75d976..a646a83390520 100644 --- a/arch/nds32/kernel/ftrace.c +++ b/arch/nds32/kernel/ftrace.c @@ -74,6 +74,14 @@ void _ftrace_caller(unsigned long parent_ip) "nop \n\t" "nop \n\t"); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + /* a placeholder for the call to ftrace_graph_caller */ + __asm__ __volatile__ ( + "ftrace_graph_call: \n\t" + "nop \n\t" + "nop \n\t" + "nop \n\t"); +#endif /* restore all state needed by the compiler epilogue */ } @@ -258,4 +266,32 @@ void __naked return_to_handler(void) "lmw.bim $r0,[$sp],$r1,#0x0 \n\t"); } +#ifdef CONFIG_DYNAMIC_FTRACE +extern unsigned long ftrace_graph_call; + +static int ftrace_modify_graph_caller(bool enable) +{ + unsigned long pc = (unsigned long)&ftrace_graph_call; + unsigned long nop_insn[3] = {INSN_NOP, INSN_NOP, INSN_NOP}; + unsigned long call_insn[3] = {INSN_NOP, INSN_NOP, INSN_NOP}; + + ftrace_gen_call_insn(call_insn, (unsigned long)ftrace_graph_caller); + + if (enable) + return ftrace_modify_code(pc, nop_insn, call_insn, true); + else + return ftrace_modify_code(pc, call_insn, nop_insn, true); +} + +int ftrace_enable_ftrace_graph_caller(void) +{ + return ftrace_modify_graph_caller(true); +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + return ftrace_modify_graph_caller(false); +} +#endif /* CONFIG_DYNAMIC_FTRACE */ + #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |