release/src-rt-6.x.4708/linux/linux-2.6.36/arch/s390/kernel/mcount.S

   1 /*
   2  * Copyright IBM Corp. 2008,2009
   3  *
   4  *   Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
   5  *
   6  */
   7
   8 #include <asm/asm-offsets.h>
   9
  10         .globl ftrace_stub
  11 ftrace_stub:
  12         br      %r14
  13
  14         .globl _mcount
  15 _mcount:
  16 #ifdef CONFIG_DYNAMIC_FTRACE
  17         br      %r14
  18
  19         .data
  20         .globl  ftrace_dyn_func
  21 ftrace_dyn_func:
  22         .long   ftrace_stub
  23         .previous
  24
  25         .globl ftrace_caller
  26 ftrace_caller:
  27 #endif
  28         stm     %r2,%r5,16(%r15)
  29         bras    %r1,2f
  30 #ifdef CONFIG_DYNAMIC_FTRACE
  31 0:      .long   ftrace_dyn_func
  32 #else
  33 0:      .long   ftrace_trace_function
  34 #endif
  35 1:      .long   function_trace_stop
  36 2:      l       %r2,1b-0b(%r1)
  37         icm     %r2,0xf,0(%r2)
  38         jnz     3f
  39         st      %r14,56(%r15)
  40         lr      %r0,%r15
  41         ahi     %r15,-96
  42         l       %r3,100(%r15)
  43         la      %r2,0(%r14)
  44         st      %r0,__SF_BACKCHAIN(%r15)
  45         la      %r3,0(%r3)
  46         l       %r14,0b-0b(%r1)
  47         l       %r14,0(%r14)
  48         basr    %r14,%r14
  49 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  50 #ifdef CONFIG_DYNAMIC_FTRACE
  51         .globl  ftrace_graph_caller
  52 ftrace_graph_caller:
  53         # This unconditional branch gets runtime patched. Change only if
  54         # you know what you are doing. See ftrace_enable_graph_caller().
  55         j       1f
  56 #endif
  57         bras    %r1,0f
  58         .long   prepare_ftrace_return
  59 0:      l       %r2,152(%r15)
  60         l       %r4,0(%r1)
  61         l       %r3,100(%r15)
  62         basr    %r14,%r4
  63         st      %r2,100(%r15)
  64 1:
  65 #endif
  66         ahi     %r15,96
  67         l       %r14,56(%r15)
  68 3:      lm      %r2,%r5,16(%r15)
  69         br      %r14
  70
  71 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  72
  73         .globl  return_to_handler
  74 return_to_handler:
  75         stm     %r2,%r5,16(%r15)
  76         st      %r14,56(%r15)
  77         lr      %r0,%r15
  78         ahi     %r15,-96
  79         st      %r0,__SF_BACKCHAIN(%r15)
  80         bras    %r1,0f
  81         .long   ftrace_return_to_handler
  82 0:      l       %r2,0b-0b(%r1)
  83         basr    %r14,%r2
  84         lr      %r14,%r2
  85         ahi     %r15,96
  86         lm      %r2,%r5,16(%r15)
  87         br      %r14
  88
  89 #endif