From 5779e3c0f5aed8a3239839ad55ad017e1278ecd7 Mon Sep 17 00:00:00 2001 From: Donglin Peng Date: Sat, 8 Apr 2023 05:42:21 -0700 Subject: [PATCH] LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL The previous patch ("function_graph: Support recording and printing the return value of function") has laid the groundwork for the for the funcgraph-retval, and this modification makes it available on the LoongArch platform. We introduce a new structure called fgraph_ret_regs for the LoongArch platform to hold return registers and the frame pointer. We then fill its content in the return_to_handler and pass its address to the function ftrace_return_to_handler to record the return value. Link: https://lkml.kernel.org/r/c5462255e435fab363895c2d7433bc0f5a140411.1680954589.git.pengdonglin@sangfor.com.cn Reviewed-by: Huacai Chen Signed-off-by: Donglin Peng Signed-off-by: Steven Rostedt (Google) --- arch/loongarch/Kconfig | 1 + arch/loongarch/include/asm/ftrace.h | 22 ++++++++++++++++++++++ arch/loongarch/kernel/asm-offsets.c | 15 ++++++++++++++- arch/loongarch/kernel/mcount.S | 14 ++++++++------ arch/loongarch/kernel/mcount_dyn.S | 15 ++++++++------- 5 files changed, 53 insertions(+), 14 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index d38b066..6c46561 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -103,6 +103,7 @@ config LOONGARCH select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API select HAVE_FUNCTION_ERROR_INJECTION + select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_GRAPH_TRACER select HAVE_FUNCTION_TRACER select HAVE_GENERIC_VDSO diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index 23e2ba7..a11996e 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -100,4 +100,26 @@ __arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) #endif /* CONFIG_FUNCTION_TRACER */ +#ifndef __ASSEMBLY__ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +struct fgraph_ret_regs { + /* a0 - a1 */ + unsigned long regs[2]; + + unsigned long fp; + unsigned long __unused; +}; + +static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs) +{ + return ret_regs->regs[0]; +} + +static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs) +{ + return ret_regs->fp; +} +#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */ +#endif + #endif /* _ASM_LOONGARCH_FTRACE_H */ diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c index 4bdb203..505e4bf 100644 --- a/arch/loongarch/kernel/asm-offsets.c +++ b/arch/loongarch/kernel/asm-offsets.c @@ -12,6 +12,7 @@ #include #include #include +#include void output_ptreg_defines(void) { @@ -264,7 +265,7 @@ void output_smpboot_defines(void) #ifdef CONFIG_HIBERNATION void output_pbe_defines(void) { - COMMENT(" Linux struct pbe offsets. "); + COMMENT("Linux struct pbe offsets."); OFFSET(PBE_ADDRESS, pbe, address); OFFSET(PBE_ORIG_ADDRESS, pbe, orig_address); OFFSET(PBE_NEXT, pbe, next); @@ -272,3 +273,15 @@ void output_pbe_defines(void) BLANK(); } #endif + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +void output_fgraph_ret_regs_defines(void) +{ + COMMENT("LoongArch fgraph_ret_regs offsets."); + OFFSET(FGRET_REGS_A0, fgraph_ret_regs, regs[0]); + OFFSET(FGRET_REGS_A1, fgraph_ret_regs, regs[1]); + OFFSET(FGRET_REGS_FP, fgraph_ret_regs, fp); + DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs)); + BLANK(); +} +#endif diff --git a/arch/loongarch/kernel/mcount.S b/arch/loongarch/kernel/mcount.S index 8cdc156..cb8e580 100644 --- a/arch/loongarch/kernel/mcount.S +++ b/arch/loongarch/kernel/mcount.S @@ -79,18 +79,20 @@ SYM_FUNC_START(ftrace_graph_caller) SYM_FUNC_END(ftrace_graph_caller) SYM_FUNC_START(return_to_handler) - PTR_ADDI sp, sp, -2 * SZREG - PTR_S a0, sp, 0 - PTR_S a1, sp, SZREG + PTR_ADDI sp, sp, -FGRET_REGS_SIZE + PTR_S a0, sp, FGRET_REGS_A0 + PTR_S a1, sp, FGRET_REGS_A1 + PTR_S zero, sp, FGRET_REGS_FP + move a0, sp bl ftrace_return_to_handler /* Restore the real parent address: a0 -> ra */ move ra, a0 - PTR_L a0, sp, 0 - PTR_L a1, sp, SZREG - PTR_ADDI sp, sp, 2 * SZREG + PTR_L a0, sp, FGRET_REGS_A0 + PTR_L a1, sp, FGRET_REGS_A1 + PTR_ADDI sp, sp, FGRET_REGS_SIZE jr ra SYM_FUNC_END(return_to_handler) #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/loongarch/kernel/mcount_dyn.S b/arch/loongarch/kernel/mcount_dyn.S index c7d961f..e16ab0b 100644 --- a/arch/loongarch/kernel/mcount_dyn.S +++ b/arch/loongarch/kernel/mcount_dyn.S @@ -136,18 +136,19 @@ SYM_CODE_END(ftrace_graph_caller) SYM_CODE_START(return_to_handler) /* Save return value regs */ - PTR_ADDI sp, sp, -2 * SZREG - PTR_S a0, sp, 0 - PTR_S a1, sp, SZREG + PTR_ADDI sp, sp, -FGRET_REGS_SIZE + PTR_S a0, sp, FGRET_REGS_A0 + PTR_S a1, sp, FGRET_REGS_A1 + PTR_S zero, sp, FGRET_REGS_FP - move a0, zero + move a0, sp bl ftrace_return_to_handler move ra, a0 /* Restore return value regs */ - PTR_L a0, sp, 0 - PTR_L a1, sp, SZREG - PTR_ADDI sp, sp, 2 * SZREG + PTR_L a0, sp, FGRET_REGS_A0 + PTR_L a1, sp, FGRET_REGS_A1 + PTR_ADDI sp, sp, FGRET_REGS_SIZE jr ra SYM_CODE_END(return_to_handler) -- 2.7.4