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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/riscv/include/asm/ftrace.h
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/riscv/include/asm/ftrace.h114
1 files changed, 114 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..d47d87c2d
--- /dev/null
+++ b/arch/riscv/include/asm/ftrace.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2017 Andes Technology Corporation */
+
+#ifndef _ASM_RISCV_FTRACE_H
+#define _ASM_RISCV_FTRACE_H
+
+/*
+ * 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)
+ *
+ *<ftrace enable>:
+ * 0: auipc t0/ra, 0x?
+ * 4: jalr t0/ra, ?(t0/ra)
+ *
+ *<ftrace disable>:
+ * 0: nop
+ * 4: nop
+ *
+ * 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_RA (0x000080e7)
+#define AUIPC_RA (0x00000097)
+#define JALR_T0 (0x000282e7)
+#define AUIPC_T0 (0x00000297)
+#define NOP4 (0x00000013)
+
+#define to_jalr_t0(offset) \
+ (((offset & JALR_OFFSET_MASK) << JALR_SHIFT) | JALR_T0)
+
+#define to_auipc_t0(offset) \
+ ((offset & JALR_SIGN_MASK) ? \
+ (((offset & AUIPC_OFFSET_MASK) + AUIPC_PAD) | AUIPC_T0) : \
+ ((offset & AUIPC_OFFSET_MASK) | AUIPC_T0))
+
+#define make_call_t0(caller, callee, call) \
+do { \
+ unsigned int offset = \
+ (unsigned long) callee - (unsigned long) caller; \
+ call[0] = to_auipc_t0(offset); \
+ call[1] = to_jalr_t0(offset); \
+} while (0)
+
+#define to_jalr_ra(offset) \
+ (((offset & JALR_OFFSET_MASK) << JALR_SHIFT) | JALR_RA)
+
+#define to_auipc_ra(offset) \
+ ((offset & JALR_SIGN_MASK) ? \
+ (((offset & AUIPC_OFFSET_MASK) + AUIPC_PAD) | AUIPC_RA) : \
+ ((offset & AUIPC_OFFSET_MASK) | AUIPC_RA))
+
+#define make_call_ra(caller, callee, call) \
+do { \
+ unsigned int offset = \
+ (unsigned long) callee - (unsigned long) caller; \
+ call[0] = to_auipc_ra(offset); \
+ call[1] = to_jalr_ra(offset); \
+} while (0)
+
+/*
+ * 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 /* CONFIG_DYNAMIC_FTRACE */
+
+#endif /* _ASM_RISCV_FTRACE_H */