scripts/tracetool/backend/simple.py

   1 #!/usr/bin/env python
   2 # -*- coding: utf-8 -*-
   3
   4 """
   5 Simple built-in backend.
   6 """
   7
   8 __author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"
   9 __copyright__  = "Copyright 2012, Lluís Vilanova <vilanova@ac.upc.edu>"
  10 __license__    = "GPL version 2 or (at your option) any later version"
  11
  12 __maintainer__ = "Stefan Hajnoczi"
  13 __email__      = "stefanha@linux.vnet.ibm.com"
  14
  15
  16 from tracetool import out
  17
  18
  19 PUBLIC = True
  20
  21
  22 def is_string(arg):
  23     strtype = ('const char*', 'char*', 'const char *', 'char *')
  24     if arg.lstrip().startswith(strtype):
  25         return True
  26     else:
  27         return False
  28
  29 def c(events):
  30     out('#include "trace.h"',
  31         '#include "trace/control.h"',
  32         '#include "trace/simple.h"',
  33         '',
  34         )
  35
  36     for num, event in enumerate(events):
  37         out('void trace_%(name)s(%(args)s)',
  38             '{',
  39             '    TraceBufferRecord rec;',
  40             name = event.name,
  41             args = event.args,
  42             )
  43         sizes = []
  44         for type_, name in event.args:
  45             if is_string(type_):
  46                 out('    size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
  47                     name = name,
  48                    )
  49                 strsizeinfo = "4 + arg%s_len" % name
  50                 sizes.append(strsizeinfo)
  51             else:
  52                 sizes.append("8")
  53         sizestr = " + ".join(sizes)
  54         if len(event.args) == 0:
  55             sizestr = '0'
  56
  57
  58         out('',
  59             '    TraceEvent *eventp = trace_event_id(%(event_id)s);',
  60             '    bool _state = trace_event_get_state_dynamic(eventp);',
  61             '    if (!_state) {',
  62             '        return;',
  63             '    }',
  64             '',
  65             '    if (trace_record_start(&rec, %(event_id)s, %(size_str)s)) {',
  66             '        return; /* Trace Buffer Full, Event Dropped ! */',
  67             '    }',
  68             event_id = num,
  69             size_str = sizestr,
  70             )
  71
  72         if len(event.args) > 0:
  73             for type_, name in event.args:
  74                 # string
  75                 if is_string(type_):
  76                     out('    trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
  77                         name = name,
  78                        )
  79                 # pointer var (not string)
  80                 elif type_.endswith('*'):
  81                     out('    trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
  82                         name = name,
  83                        )
  84                 # primitive data type
  85                 else:
  86                     out('    trace_record_write_u64(&rec, (uint64_t)%(name)s);',
  87                        name = name,
  88                        )
  89
  90         out('    trace_record_finish(&rec);',
  91             '}',
  92             '')
  93
  94
  95 def h(events):
  96     out('#include "trace/simple.h"',
  97         '')
  98
  99     for event in events:
 100         out('void trace_%(name)s(%(args)s);',
 101             name = event.name,
 102             args = event.args,
 103             )