[PATCH v10 7/8] LoongArch: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL
From: Donglin Peng <hidden>
Date: 2023-03-31 12:50:11
Also in:
linux-arm-kernel, linux-riscv, lkml, loongarch
Subsystem:
function hooks (ftrace), loongarch, the rest · Maintainers:
Steven Rostedt, Masami Hiramatsu, Huacai Chen, Linus Torvalds
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.
Signed-off-by: Donglin Peng <redacted>
---
v10:
- Fix code style issues for LoongArch
- Use CONFIG_FUNCTION_GRAPH_TRACER to control fgraph_ret_regs definition
v9:
- Fix stack pointer align issues
- Update the commit message
v8:
- Modify the control range of CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
---
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 7fd51257e0ed..4bf60132869b 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig@@ -99,6 +99,7 @@ config LOONGARCH select HAVE_FAST_GUP select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_ARG_ACCESS_API + 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 3418d32d4fc7..22797b7504b5 100644
--- a/arch/loongarch/include/asm/ftrace.h
+++ b/arch/loongarch/include/asm/ftrace.h@@ -63,4 +63,26 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, #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 4bdb203fc66e..505e4bf59603 100644
--- a/arch/loongarch/kernel/asm-offsets.c
+++ b/arch/loongarch/kernel/asm-offsets.c@@ -12,6 +12,7 @@ #include <asm/cpu-info.h> #include <asm/ptrace.h> #include <asm/processor.h> +#include <asm/ftrace.h> 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 8cdc1563cd33..cb8e5803de4b 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 bbabf06244c2..ec24ae1de741 100644
--- a/arch/loongarch/kernel/mcount_dyn.S
+++ b/arch/loongarch/kernel/mcount_dyn.S@@ -131,18 +131,19 @@ 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)
--
2.25.1