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 def is_string(arg):
  19     strtype = ('const char*', 'char*', 'const char *', 'char *')
  20     if arg.lstrip().startswith(strtype):
  21         return True
  22     else:
  23         return False
  24
  25 def c(events):
  26     out('#include "trace.h"',
  27         '#include "trace/simple.h"',
  28         '',
  29         'TraceEvent trace_list[] = {')
  30
  31     for e in events:
  32         out('{.tp_name = "%(name)s", .state=0},',
  33             name = e.name,
  34             )
  35
  36     out('};',
  37         '')
  38
  39     for num, event in enumerate(events):
  40         out('void trace_%(name)s(%(args)s)',
  41             '{',
  42             '    TraceBufferRecord rec;',
  43             name = event.name,
  44             args = event.args,
  45             )
  46         sizes = []
  47         for type_, name in event.args:
  48             if is_string(type_):
  49                 out('    size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
  50                     name = name,
  51                    )
  52                 strsizeinfo = "4 + arg%s_len" % name
  53                 sizes.append(strsizeinfo)
  54             else:
  55                 sizes.append("8")
  56         sizestr = " + ".join(sizes)
  57         if len(event.args) == 0:
  58             sizestr = '0'
  59
  60
  61         out('',
  62             '    if (!trace_list[%(event_id)s].state) {',
  63             '        return;',
  64             '    }',
  65             '',
  66             '    if (trace_record_start(&rec, %(event_id)s, %(size_str)s)) {',
  67             '        return; /* Trace Buffer Full, Event Dropped ! */',
  68             '    }',
  69             event_id = num,
  70             size_str = sizestr,
  71             )
  72
  73         if len(event.args) > 0:
  74             for type_, name in event.args:
  75                 # string
  76                 if is_string(type_):
  77                     out('    trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
  78                         name = name,
  79                        )
  80                 # pointer var (not string)
  81                 elif type_.endswith('*'):
  82                     out('    trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
  83                         name = name,
  84                        )
  85                 # primitive data type
  86                 else:
  87                     out('    trace_record_write_u64(&rec, (uint64_t)%(name)s);',
  88                        name = name,
  89                        )
  90
  91         out('    trace_record_finish(&rec);',
  92             '}',
  93             '')
  94
  95
  96 def h(events):
  97     out('#include "trace/simple.h"',
  98         '')
  99
 100     for event in events:
 101         out('void trace_%(name)s(%(args)s);',
 102             name = event.name,
 103             args = event.args,
 104             )
 105     out('')
 106     out('#define NR_TRACE_EVENTS %d' % len(events))
 107     out('extern TraceEvent trace_list[NR_TRACE_EVENTS];')