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 2012-2014, 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
  30 def generate_h_begin(events):
  31     for event in events:
  32         out('void _simple_%(api)s(%(args)s);',
  33             api=event.api(),
  34             args=event.args)
  35     out('')
  36
  37
  38 def generate_h(event):
  39     out('        _simple_%(api)s(%(args)s);',
  40         api=event.api(),
  41         args=", ".join(event.args.names()))
  42
  43
  44 def generate_c_begin(events):
  45     out('#include "qemu/osdep.h"',
  46         '#include "trace.h"',
  47         '#include "trace/control.h"',
  48         '#include "trace/simple.h"',
  49         '')
  50
  51
  52 def generate_c(event):
  53     out('void _simple_%(api)s(%(args)s)',
  54         '{',
  55         '    TraceBufferRecord rec;',
  56         api=event.api(),
  57         args=event.args)
  58     sizes = []
  59     for type_, name in event.args:
  60         if is_string(type_):
  61             out('    size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
  62                 name=name)
  63             strsizeinfo = "4 + arg%s_len" % name
  64             sizes.append(strsizeinfo)
  65         else:
  66             sizes.append("8")
  67     sizestr = " + ".join(sizes)
  68     if len(event.args) == 0:
  69         sizestr = '0'
  70
  71     event_id = 'TRACE_' + event.name.upper()
  72     if "vcpu" in event.properties:
  73         # already checked on the generic format code
  74         cond = "true"
  75     else:
  76         cond = "trace_event_get_state(%s)" % event_id
  77
  78     out('',
  79         '    if (!%(cond)s) {',
  80         '        return;',
  81         '    }',
  82         '',
  83         '    if (trace_record_start(&rec, %(event_id)s, %(size_str)s)) {',
  84         '        return; /* Trace Buffer Full, Event Dropped ! */',
  85         '    }',
  86         cond=cond,
  87         event_id=event_id,
  88         size_str=sizestr)
  89
  90     if len(event.args) > 0:
  91         for type_, name in event.args:
  92             # string
  93             if is_string(type_):
  94                 out('    trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
  95                     name=name)
  96             # pointer var (not string)
  97             elif type_.endswith('*'):
  98                 out('    trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
  99                     name=name)
 100             # primitive data type
 101             else:
 102                 out('    trace_record_write_u64(&rec, (uint64_t)%(name)s);',
 103                    name=name)
 104
 105     out('    trace_record_finish(&rec);',
 106         '}',
 107         '')