arch/tile/kernel/mcount_64.S

   1 /*
   2  * Copyright 2012 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  *
  14  * TILE-Gx specific __mcount support
  15  */
  16
  17 #include <linux/linkage.h>
  18 #include <asm/ftrace.h>
  19
  20 #define REGSIZE 8
  21
  22         .text
  23         .global __mcount
  24
  25         .macro  MCOUNT_SAVE_REGS
  26         addli   sp, sp, -REGSIZE
  27         {
  28          st     sp, lr
  29          addli  r29, sp, - (12 * REGSIZE)
  30         }
  31         {
  32          addli  sp, sp, - (13 * REGSIZE)
  33          st     r29, sp
  34         }
  35         addli   r29, r29, REGSIZE
  36         { st    r29, r0; addli  r29, r29, REGSIZE }
  37         { st    r29, r1; addli  r29, r29, REGSIZE }
  38         { st    r29, r2; addli  r29, r29, REGSIZE }
  39         { st    r29, r3; addli  r29, r29, REGSIZE }
  40         { st    r29, r4; addli  r29, r29, REGSIZE }
  41         { st    r29, r5; addli  r29, r29, REGSIZE }
  42         { st    r29, r6; addli  r29, r29, REGSIZE }
  43         { st    r29, r7; addli  r29, r29, REGSIZE }
  44         { st    r29, r8; addli  r29, r29, REGSIZE }
  45         { st    r29, r9; addli  r29, r29, REGSIZE }
  46         { st    r29, r10; addli r29, r29, REGSIZE }
  47         .endm
  48
  49         .macro  MCOUNT_RESTORE_REGS
  50         addli   r29, sp, (2 * REGSIZE)
  51         { ld    r0, r29; addli  r29, r29, REGSIZE }
  52         { ld    r1, r29; addli  r29, r29, REGSIZE }
  53         { ld    r2, r29; addli  r29, r29, REGSIZE }
  54         { ld    r3, r29; addli  r29, r29, REGSIZE }
  55         { ld    r4, r29; addli  r29, r29, REGSIZE }
  56         { ld    r5, r29; addli  r29, r29, REGSIZE }
  57         { ld    r6, r29; addli  r29, r29, REGSIZE }
  58         { ld    r7, r29; addli  r29, r29, REGSIZE }
  59         { ld    r8, r29; addli  r29, r29, REGSIZE }
  60         { ld    r9, r29; addli  r29, r29, REGSIZE }
  61         { ld    r10, r29; addli lr, sp, (13 * REGSIZE) }
  62         { ld    lr, lr;  addli  sp, sp, (14 * REGSIZE) }
  63         .endm
  64
  65         .macro  RETURN_BACK
  66         { move  r12, lr; move   lr, r10 }
  67         jrp     r12
  68         .endm
  69
  70 #ifdef CONFIG_DYNAMIC_FTRACE
  71
  72         .align  64
  73 STD_ENTRY(__mcount)
  74 __mcount:
  75         j       ftrace_stub
  76 STD_ENDPROC(__mcount)
  77
  78         .align  64
  79 STD_ENTRY(ftrace_caller)
  80         moveli  r11, hw2_last(function_trace_stop)
  81         { shl16insli    r11, r11, hw1(function_trace_stop); move r12, lr }
  82         { shl16insli    r11, r11, hw0(function_trace_stop); move lr, r10 }
  83         ld      r11, r11
  84         beqz    r11, 1f
  85         jrp     r12
  86
  87 1:
  88         { move  r10, lr; move   lr, r12 }
  89         MCOUNT_SAVE_REGS
  90
  91         /* arg1: self return address */
  92         /* arg2: parent's return address */
  93         { move  r0, lr; move    r1, r10 }
  94
  95         .global ftrace_call
  96 ftrace_call:
  97         /*
  98          * a placeholder for the call to a real tracing function, i.e.
  99          * ftrace_trace_function()
 100          */
 101         nop
 102
 103 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 104         .global ftrace_graph_call
 105 ftrace_graph_call:
 106         /*
 107          * a placeholder for the call to a real tracing function, i.e.
 108          * ftrace_graph_caller()
 109          */
 110         nop
 111 #endif
 112         MCOUNT_RESTORE_REGS
 113         .global ftrace_stub
 114 ftrace_stub:
 115         RETURN_BACK
 116 STD_ENDPROC(ftrace_caller)
 117
 118 #else /* ! CONFIG_DYNAMIC_FTRACE */
 119
 120         .align  64
 121 STD_ENTRY(__mcount)
 122         moveli  r11, hw2_last(function_trace_stop)
 123         { shl16insli    r11, r11, hw1(function_trace_stop); move r12, lr }
 124         { shl16insli    r11, r11, hw0(function_trace_stop); move lr, r10 }
 125         ld      r11, r11
 126         beqz    r11, 1f
 127         jrp     r12
 128
 129 1:
 130         { move  r10, lr; move   lr, r12 }
 131         {
 132          moveli r11, hw2_last(ftrace_trace_function)
 133          moveli r13, hw2_last(ftrace_stub)
 134         }
 135         {
 136          shl16insli     r11, r11, hw1(ftrace_trace_function)
 137          shl16insli     r13, r13, hw1(ftrace_stub)
 138         }
 139         {
 140          shl16insli     r11, r11, hw0(ftrace_trace_function)
 141          shl16insli     r13, r13, hw0(ftrace_stub)
 142         }
 143
 144         ld      r11, r11
 145         sub     r14, r13, r11
 146         bnez    r14, static_trace
 147
 148 #ifdef  CONFIG_FUNCTION_GRAPH_TRACER
 149         moveli  r15, hw2_last(ftrace_graph_return)
 150         shl16insli      r15, r15, hw1(ftrace_graph_return)
 151         shl16insli      r15, r15, hw0(ftrace_graph_return)
 152         ld      r15, r15
 153         sub     r15, r15, r13
 154         bnez    r15, ftrace_graph_caller
 155
 156         {
 157          moveli r16, hw2_last(ftrace_graph_entry)
 158          moveli r17, hw2_last(ftrace_graph_entry_stub)
 159         }
 160         {
 161          shl16insli     r16, r16, hw1(ftrace_graph_entry)
 162          shl16insli     r17, r17, hw1(ftrace_graph_entry_stub)
 163         }
 164         {
 165          shl16insli     r16, r16, hw0(ftrace_graph_entry)
 166          shl16insli     r17, r17, hw0(ftrace_graph_entry_stub)
 167         }
 168         ld      r16, r16
 169         sub     r17, r16, r17
 170         bnez    r17, ftrace_graph_caller
 171
 172 #endif
 173         RETURN_BACK
 174
 175 static_trace:
 176         MCOUNT_SAVE_REGS
 177
 178         /* arg1: self return address */
 179         /* arg2: parent's return address */
 180         { move  r0, lr; move    r1, r10 }
 181
 182         /* call ftrace_trace_function() */
 183         jalr    r11
 184
 185         MCOUNT_RESTORE_REGS
 186
 187         .global ftrace_stub
 188 ftrace_stub:
 189         RETURN_BACK
 190 STD_ENDPROC(__mcount)
 191
 192 #endif  /* ! CONFIG_DYNAMIC_FTRACE */
 193
 194 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 195
 196 STD_ENTRY(ftrace_graph_caller)
 197 ftrace_graph_caller:
 198 #ifndef CONFIG_DYNAMIC_FTRACE
 199         MCOUNT_SAVE_REGS
 200 #endif
 201
 202         /* arg1: Get the location of the parent's return address */
 203         addi    r0, sp, 12 * REGSIZE
 204         /* arg2: Get self return address */
 205         move    r1, lr
 206
 207         jal prepare_ftrace_return
 208
 209         MCOUNT_RESTORE_REGS
 210         RETURN_BACK
 211 STD_ENDPROC(ftrace_graph_caller)
 212
 213         .global return_to_handler
 214 return_to_handler:
 215         MCOUNT_SAVE_REGS
 216
 217         jal     ftrace_return_to_handler
 218         /* restore the real parent address */
 219         move    r11, r0
 220
 221         MCOUNT_RESTORE_REGS
 222         jr      r11
 223
 224 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */