arch/sparc/lib/mcount.S

   1 /*
   2  * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com)
   3  *
   4  * This file implements mcount(), which is used to collect profiling data.
   5  * This can also be tweaked for kernel stack overflow detection.
   6  */
   7
   8 #include <linux/linkage.h>
   9 #include <asm/export.h>
  10
  11 /*
  12  * This is the main variant and is called by C code.  GCC's -pg option
  13  * automatically instruments every C function with a call to this.
  14  */
  15
  16         .text
  17         .align          32
  18         .globl          _mcount
  19         .type           _mcount,#function
  20         EXPORT_SYMBOL(_mcount)
  21         .globl          mcount
  22         .type           mcount,#function
  23 _mcount:
  24 mcount:
  25 #ifdef CONFIG_FUNCTION_TRACER
  26 #ifdef CONFIG_DYNAMIC_FTRACE
  27         /* Do nothing, the retl/nop below is all we need.  */
  28 #else
  29         sethi           %hi(ftrace_trace_function), %g1
  30         sethi           %hi(ftrace_stub), %g2
  31         ldx             [%g1 + %lo(ftrace_trace_function)], %g1
  32         or              %g2, %lo(ftrace_stub), %g2
  33         cmp             %g1, %g2
  34         be,pn           %icc, 1f
  35          mov            %i7, %g3
  36         save            %sp, -176, %sp
  37         mov             %g3, %o1
  38         jmpl            %g1, %o7
  39          mov            %i7, %o0
  40         ret
  41          restore
  42         /* not reached */
  43 1:
  44 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  45         sethi           %hi(ftrace_graph_return), %g1
  46         ldx             [%g1 + %lo(ftrace_graph_return)], %g3
  47         cmp             %g2, %g3
  48         bne,pn          %xcc, 5f
  49          sethi          %hi(ftrace_graph_entry_stub), %g2
  50         sethi           %hi(ftrace_graph_entry), %g1
  51         or              %g2, %lo(ftrace_graph_entry_stub), %g2
  52         ldx             [%g1 + %lo(ftrace_graph_entry)], %g1
  53         cmp             %g1, %g2
  54         be,pt           %xcc, 2f
  55          nop
  56 5:      mov             %i7, %g2
  57         mov             %fp, %g3
  58         save            %sp, -176, %sp
  59         mov             %g2, %l0
  60         ba,pt           %xcc, ftrace_graph_caller
  61          mov            %g3, %l1
  62 #endif
  63 2:
  64 #endif
  65 #endif
  66         retl
  67          nop
  68         .size           _mcount,.-_mcount
  69         .size           mcount,.-mcount
  70
  71 #ifdef CONFIG_FUNCTION_TRACER
  72         .globl          ftrace_stub
  73         .type           ftrace_stub,#function
  74 ftrace_stub:
  75         retl
  76          nop
  77         .size           ftrace_stub,.-ftrace_stub
  78 #ifdef CONFIG_DYNAMIC_FTRACE
  79         .globl          ftrace_caller
  80         .type           ftrace_caller,#function
  81 ftrace_caller:
  82         mov             %i7, %g2
  83         mov             %fp, %g3
  84         save            %sp, -176, %sp
  85         mov             %g2, %o1
  86         mov             %g2, %l0
  87         mov             %g3, %l1
  88         .globl          ftrace_call
  89 ftrace_call:
  90         call            ftrace_stub
  91          mov            %i7, %o0
  92 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  93         .globl          ftrace_graph_call
  94 ftrace_graph_call:
  95         call            ftrace_stub
  96          nop
  97 #endif
  98         ret
  99          restore
 100 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 101         .size           ftrace_graph_call,.-ftrace_graph_call
 102 #endif
 103         .size           ftrace_call,.-ftrace_call
 104         .size           ftrace_caller,.-ftrace_caller
 105 #endif
 106 #endif
 107
 108 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 109 ENTRY(ftrace_graph_caller)
 110         mov             %l0, %o0
 111         mov             %i7, %o1
 112         call            prepare_ftrace_return
 113          mov            %l1, %o2
 114         ret
 115          restore        %o0, -8, %i7
 116 END(ftrace_graph_caller)
 117
 118 ENTRY(return_to_handler)
 119         save            %sp, -176, %sp
 120         call            ftrace_return_to_handler
 121          mov            %fp, %o0
 122         jmpl            %o0 + 8, %g0
 123          restore
 124 END(return_to_handler)
 125 #endif