From ac7127e1cc65aeb578998c992a05dbc80fa18f0f Mon Sep 17 00:00:00 2001 From: Qing Zhang Date: Sat, 10 Dec 2022 22:40:16 +0800 Subject: [PATCH] LoongArch/ftrace: Add HAVE_DYNAMIC_FTRACE_WITH_ARGS support Allow for arguments to be passed in to ftrace_regs by default. If this is set, then arguments and stack can be found from the pt_regs. 1. HAVE_DYNAMIC_FTRACE_WITH_ARGS don't need special hook for graph tracer entry point, but instead we can use graph_ops::func function to install the return_hooker. 2. Livepatch requires this option in the future. Signed-off-by: Qing Zhang Signed-off-by: Huacai Chen --- arch/loongarch/Kconfig | 1 + arch/loongarch/include/asm/ftrace.h | 17 +++++++++++++++++ arch/loongarch/kernel/ftrace_dyn.c | 11 +++++++++++ 3 files changed, 29 insertions(+) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index f2d1b2a..a36bb0f 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -89,6 +89,7 @@ config LOONGARCH select HAVE_DEBUG_STACKOVERFLOW select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE + select HAVE_DYNAMIC_FTRACE_WITH_ARGS select HAVE_DYNAMIC_FTRACE_WITH_REGS select HAVE_EBPF_JIT select HAVE_EXIT_THREAD diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index dd4a0c8..ee7fefa 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -37,6 +37,23 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent); #endif /* CONFIG_DYNAMIC_FTRACE */ +#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS +struct ftrace_ops; + +struct ftrace_regs { + struct pt_regs regs; +}; + +static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) +{ + return &fregs->regs; +} + +#define ftrace_graph_func ftrace_graph_func +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs); +#endif + #endif /* __ASSEMBLY__ */ #endif /* CONFIG_FUNCTION_TRACER */ diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c index d6f3091..439ba82 100644 --- a/arch/loongarch/kernel/ftrace_dyn.c +++ b/arch/loongarch/kernel/ftrace_dyn.c @@ -139,6 +139,16 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent) *parent = return_hooker; } +#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) +{ + struct pt_regs *regs = &fregs->regs; + unsigned long *parent = (unsigned long *)®s->regs[1]; + + prepare_ftrace_return(ip, (unsigned long *)parent); +} +#else static int ftrace_modify_graph_caller(bool enable) { u32 branch, nop; @@ -166,4 +176,5 @@ int ftrace_disable_ftrace_graph_caller(void) { return ftrace_modify_graph_caller(false); } +#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- 2.7.4