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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Copyright (C) 2017 Andes Technology Corporation */
3
4/*
5 * The graph frame test is not possible if CONFIG_FRAME_POINTER is not enabled.
6 * Check arch/riscv/kernel/mcount.S for detail.
7 */
8#if defined(CONFIG_FUNCTION_GRAPH_TRACER) && defined(CONFIG_FRAME_POINTER)
9#define HAVE_FUNCTION_GRAPH_FP_TEST
10#endif
11#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
12
13#define ARCH_SUPPORTS_FTRACE_OPS 1
14#ifndef __ASSEMBLY__
15void _mcount(void);
16static inline unsigned long ftrace_call_adjust(unsigned long addr)
17{
18 return addr;
19}
20
21struct dyn_arch_ftrace {
22};
23#endif
24
25#ifdef CONFIG_DYNAMIC_FTRACE
26/*
27 * A general call in RISC-V is a pair of insts:
28 * 1) auipc: setting high-20 pc-related bits to ra register
29 * 2) jalr: setting low-12 offset to ra, jump to ra, and set ra to
30 * return address (original pc + 4)
31 *
32 * Dynamic ftrace generates probes to call sites, so we must deal with
33 * both auipc and jalr at the same time.
34 */
35
36#define MCOUNT_ADDR ((unsigned long)_mcount)
37#define JALR_SIGN_MASK (0x00000800)
38#define JALR_OFFSET_MASK (0x00000fff)
39#define AUIPC_OFFSET_MASK (0xfffff000)
40#define AUIPC_PAD (0x00001000)
41#define JALR_SHIFT 20
42#define JALR_BASIC (0x000080e7)
43#define AUIPC_BASIC (0x00000097)
44#define NOP4 (0x00000013)
45
46#define make_call(caller, callee, call) \
47do { \
48 call[0] = to_auipc_insn((unsigned int)((unsigned long)callee - \
49 (unsigned long)caller)); \
50 call[1] = to_jalr_insn((unsigned int)((unsigned long)callee - \
51 (unsigned long)caller)); \
52} while (0)
53
54#define to_jalr_insn(offset) \
55 (((offset & JALR_OFFSET_MASK) << JALR_SHIFT) | JALR_BASIC)
56
57#define to_auipc_insn(offset) \
58 ((offset & JALR_SIGN_MASK) ? \
59 (((offset & AUIPC_OFFSET_MASK) + AUIPC_PAD) | AUIPC_BASIC) : \
60 ((offset & AUIPC_OFFSET_MASK) | AUIPC_BASIC))
61
62/*
63 * Let auipc+jalr be the basic *mcount unit*, so we make it 8 bytes here.
64 */
65#define MCOUNT_INSN_SIZE 8
66#endif