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Diffstat (limited to 'arch/riscv/include/asm/ftrace.h')
-rw-r--r-- | arch/riscv/include/asm/ftrace.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h new file mode 100644 index 000000000..693c3839a --- /dev/null +++ b/arch/riscv/include/asm/ftrace.h @@ -0,0 +1,83 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2017 Andes Technology Corporation */ + +/* + * The graph frame test is not possible if CONFIG_FRAME_POINTER is not enabled. + * Check arch/riscv/kernel/mcount.S for detail. + */ +#if defined(CONFIG_FUNCTION_GRAPH_TRACER) && defined(CONFIG_FRAME_POINTER) +#define HAVE_FUNCTION_GRAPH_FP_TEST +#endif +#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR + +/* + * Clang prior to 13 had "mcount" instead of "_mcount": + * https://reviews.llvm.org/D98881 + */ +#if defined(CONFIG_CC_IS_GCC) || CONFIG_CLANG_VERSION >= 130000 +#define MCOUNT_NAME _mcount +#else +#define MCOUNT_NAME mcount +#endif + +#define ARCH_SUPPORTS_FTRACE_OPS 1 +#ifndef __ASSEMBLY__ +void MCOUNT_NAME(void); +static inline unsigned long ftrace_call_adjust(unsigned long addr) +{ + return addr; +} + +struct dyn_arch_ftrace { +}; +#endif + +#ifdef CONFIG_DYNAMIC_FTRACE +/* + * A general call in RISC-V is a pair of insts: + * 1) auipc: setting high-20 pc-related bits to ra register + * 2) jalr: setting low-12 offset to ra, jump to ra, and set ra to + * return address (original pc + 4) + * + * Dynamic ftrace generates probes to call sites, so we must deal with + * both auipc and jalr at the same time. + */ + +#define MCOUNT_ADDR ((unsigned long)MCOUNT_NAME) +#define JALR_SIGN_MASK (0x00000800) +#define JALR_OFFSET_MASK (0x00000fff) +#define AUIPC_OFFSET_MASK (0xfffff000) +#define AUIPC_PAD (0x00001000) +#define JALR_SHIFT 20 +#define JALR_BASIC (0x000080e7) +#define AUIPC_BASIC (0x00000097) +#define NOP4 (0x00000013) + +#define make_call(caller, callee, call) \ +do { \ + call[0] = to_auipc_insn((unsigned int)((unsigned long)callee - \ + (unsigned long)caller)); \ + call[1] = to_jalr_insn((unsigned int)((unsigned long)callee - \ + (unsigned long)caller)); \ +} while (0) + +#define to_jalr_insn(offset) \ + (((offset & JALR_OFFSET_MASK) << JALR_SHIFT) | JALR_BASIC) + +#define to_auipc_insn(offset) \ + ((offset & JALR_SIGN_MASK) ? \ + (((offset & AUIPC_OFFSET_MASK) + AUIPC_PAD) | AUIPC_BASIC) : \ + ((offset & AUIPC_OFFSET_MASK) | AUIPC_BASIC)) + +/* + * Let auipc+jalr be the basic *mcount unit*, so we make it 8 bytes here. + */ +#define MCOUNT_INSN_SIZE 8 + +#ifndef __ASSEMBLY__ +struct dyn_ftrace; +int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); +#define ftrace_init_nop ftrace_init_nop +#endif + +#endif |