root/arch/riscv/kernel/mcount-dyn.S

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* Copyright (C) 2017 Andes Technology Corporation */
   3 
   4 #include <linux/init.h>
   5 #include <linux/linkage.h>
   6 #include <asm/asm.h>
   7 #include <asm/csr.h>
   8 #include <asm/unistd.h>
   9 #include <asm/thread_info.h>
  10 #include <asm/asm-offsets.h>
  11 #include <asm-generic/export.h>
  12 #include <asm/ftrace.h>
  13 
  14         .text
  15 
  16         .macro SAVE_ABI_STATE
  17 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  18         addi    sp, sp, -48
  19         sd      s0, 32(sp)
  20         sd      ra, 40(sp)
  21         addi    s0, sp, 48
  22         sd      t0, 24(sp)
  23         sd      t1, 16(sp)
  24 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
  25         sd      t2, 8(sp)
  26 #endif
  27 #else
  28         addi    sp, sp, -16
  29         sd      s0, 0(sp)
  30         sd      ra, 8(sp)
  31         addi    s0, sp, 16
  32 #endif
  33         .endm
  34 
  35         .macro RESTORE_ABI_STATE
  36 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  37         ld      s0, 32(sp)
  38         ld      ra, 40(sp)
  39         addi    sp, sp, 48
  40 #else
  41         ld      ra, 8(sp)
  42         ld      s0, 0(sp)
  43         addi    sp, sp, 16
  44 #endif
  45         .endm
  46 
  47         .macro RESTORE_GRAPH_ARGS
  48         ld      a0, 24(sp)
  49         ld      a1, 16(sp)
  50 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
  51         ld      a2, 8(sp)
  52 #endif
  53         .endm
  54 
  55 ENTRY(ftrace_graph_caller)
  56         addi    sp, sp, -16
  57         sd      s0, 0(sp)
  58         sd      ra, 8(sp)
  59         addi    s0, sp, 16
  60 ftrace_graph_call:
  61         .global ftrace_graph_call
  62         /*
  63          * Calling ftrace_enable/disable_ftrace_graph_caller would overwrite the
  64          * call below.  Check ftrace_modify_all_code for details.
  65          */
  66         call    ftrace_stub
  67         ld      ra, 8(sp)
  68         ld      s0, 0(sp)
  69         addi    sp, sp, 16
  70         ret
  71 ENDPROC(ftrace_graph_caller)
  72 
  73 ENTRY(ftrace_caller)
  74         /*
  75          * a0: the address in the caller when calling ftrace_caller
  76          * a1: the caller's return address
  77          * a2: the address of global variable function_trace_op
  78          */
  79         ld      a1, -8(s0)
  80         addi    a0, ra, -MCOUNT_INSN_SIZE
  81         la      t5, function_trace_op
  82         ld      a2, 0(t5)
  83 
  84 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  85         /*
  86          * the graph tracer (specifically, prepare_ftrace_return) needs these
  87          * arguments but for now the function tracer occupies the regs, so we
  88          * save them in temporary regs to recover later.
  89          */
  90         addi    t0, s0, -8
  91         mv      t1, a0
  92 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
  93         ld      t2, -16(s0)
  94 #endif
  95 #endif
  96 
  97         SAVE_ABI_STATE
  98 ftrace_call:
  99         .global ftrace_call
 100         /*
 101          * For the dynamic ftrace to work, here we should reserve at least
 102          * 8 bytes for a functional auipc-jalr pair.  The following call
 103          * serves this purpose.
 104          *
 105          * Calling ftrace_update_ftrace_func would overwrite the nops below.
 106          * Check ftrace_modify_all_code for details.
 107          */
 108         call    ftrace_stub
 109 
 110 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 111         RESTORE_GRAPH_ARGS
 112         call    ftrace_graph_caller
 113 #endif
 114 
 115         RESTORE_ABI_STATE
 116         ret
 117 ENDPROC(ftrace_caller)
 118 
 119 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
 120         .macro SAVE_ALL
 121         addi    sp, sp, -(PT_SIZE_ON_STACK+16)
 122         sd      s0, (PT_SIZE_ON_STACK)(sp)
 123         sd      ra, (PT_SIZE_ON_STACK+8)(sp)
 124         addi    s0, sp, (PT_SIZE_ON_STACK+16)
 125 
 126         sd x1,  PT_RA(sp)
 127         sd x2,  PT_SP(sp)
 128         sd x3,  PT_GP(sp)
 129         sd x4,  PT_TP(sp)
 130         sd x5,  PT_T0(sp)
 131         sd x6,  PT_T1(sp)
 132         sd x7,  PT_T2(sp)
 133         sd x8,  PT_S0(sp)
 134         sd x9,  PT_S1(sp)
 135         sd x10, PT_A0(sp)
 136         sd x11, PT_A1(sp)
 137         sd x12, PT_A2(sp)
 138         sd x13, PT_A3(sp)
 139         sd x14, PT_A4(sp)
 140         sd x15, PT_A5(sp)
 141         sd x16, PT_A6(sp)
 142         sd x17, PT_A7(sp)
 143         sd x18, PT_S2(sp)
 144         sd x19, PT_S3(sp)
 145         sd x20, PT_S4(sp)
 146         sd x21, PT_S5(sp)
 147         sd x22, PT_S6(sp)
 148         sd x23, PT_S7(sp)
 149         sd x24, PT_S8(sp)
 150         sd x25, PT_S9(sp)
 151         sd x26, PT_S10(sp)
 152         sd x27, PT_S11(sp)
 153         sd x28, PT_T3(sp)
 154         sd x29, PT_T4(sp)
 155         sd x30, PT_T5(sp)
 156         sd x31, PT_T6(sp)
 157         .endm
 158 
 159         .macro RESTORE_ALL
 160         ld x1,  PT_RA(sp)
 161         ld x2,  PT_SP(sp)
 162         ld x3,  PT_GP(sp)
 163         ld x4,  PT_TP(sp)
 164         ld x5,  PT_T0(sp)
 165         ld x6,  PT_T1(sp)
 166         ld x7,  PT_T2(sp)
 167         ld x8,  PT_S0(sp)
 168         ld x9,  PT_S1(sp)
 169         ld x10, PT_A0(sp)
 170         ld x11, PT_A1(sp)
 171         ld x12, PT_A2(sp)
 172         ld x13, PT_A3(sp)
 173         ld x14, PT_A4(sp)
 174         ld x15, PT_A5(sp)
 175         ld x16, PT_A6(sp)
 176         ld x17, PT_A7(sp)
 177         ld x18, PT_S2(sp)
 178         ld x19, PT_S3(sp)
 179         ld x20, PT_S4(sp)
 180         ld x21, PT_S5(sp)
 181         ld x22, PT_S6(sp)
 182         ld x23, PT_S7(sp)
 183         ld x24, PT_S8(sp)
 184         ld x25, PT_S9(sp)
 185         ld x26, PT_S10(sp)
 186         ld x27, PT_S11(sp)
 187         ld x28, PT_T3(sp)
 188         ld x29, PT_T4(sp)
 189         ld x30, PT_T5(sp)
 190         ld x31, PT_T6(sp)
 191 
 192         ld      s0, (PT_SIZE_ON_STACK)(sp)
 193         ld      ra, (PT_SIZE_ON_STACK+8)(sp)
 194         addi    sp, sp, (PT_SIZE_ON_STACK+16)
 195         .endm
 196 
 197         .macro RESTORE_GRAPH_REG_ARGS
 198         ld      a0, PT_T0(sp)
 199         ld      a1, PT_T1(sp)
 200 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
 201         ld      a2, PT_T2(sp)
 202 #endif
 203         .endm
 204 
 205 /*
 206  * Most of the contents are the same as ftrace_caller.
 207  */
 208 ENTRY(ftrace_regs_caller)
 209         /*
 210          * a3: the address of all registers in the stack
 211          */
 212         ld      a1, -8(s0)
 213         addi    a0, ra, -MCOUNT_INSN_SIZE
 214         la      t5, function_trace_op
 215         ld      a2, 0(t5)
 216         addi    a3, sp, -(PT_SIZE_ON_STACK+16)
 217 
 218 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 219         addi    t0, s0, -8
 220         mv      t1, a0
 221 #ifdef HAVE_FUNCTION_GRAPH_FP_TEST
 222         ld      t2, -16(s0)
 223 #endif
 224 #endif
 225         SAVE_ALL
 226 
 227 ftrace_regs_call:
 228         .global ftrace_regs_call
 229         call    ftrace_stub
 230 
 231 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 232         RESTORE_GRAPH_REG_ARGS
 233         call    ftrace_graph_caller
 234 #endif
 235 
 236         RESTORE_ALL
 237         ret
 238 ENDPROC(ftrace_regs_caller)
 239 #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */