[PATCH 04/20 v2] tracing/x86: Add arch_get_func_args() function
From: Steven Rostedt <rostedt@goodmis.org>
Date: 2018-02-07 20:32:39
Also in:
lkml
Subsystem:
function hooks (ftrace), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Steven Rostedt, Masami Hiramatsu, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Add function to get the function arguments from pt_regs. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> --- arch/x86/kernel/ftrace.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 01ebcb6f263e..5e845c8cf89d 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c@@ -46,6 +46,34 @@ int ftrace_arch_code_modify_post_process(void) return 0; } +int arch_get_func_args(struct pt_regs *regs, + int start, int end, long *args) +{ +#ifdef CONFIG_X86_64 +# define MAX_ARGS 6 +# define INIT_REGS \ + { regs->di, regs->si, regs->dx, \ + regs->cx, regs->r8, regs->r9 \ + } +#else +# define MAX_ARGS 3 +# define INIT_REGS \ + { regs->ax, regs->dx, regs->cx } +#endif + if (!regs) + return MAX_ARGS; + + { + long pt_args[] = INIT_REGS; + int i; + + for (i = start; i <= end && i < MAX_ARGS; i++) + args[i - start] = pt_args[i]; + + return i - start; + } +} + union ftrace_code_union { char code[MCOUNT_INSN_SIZE]; struct {
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2.15.1