scripts/tracetool/backend/simple.py

   1 # -*- coding: utf-8 -*-
   2
   3 """
   4 Simple built-in backend.
   5 """
   6
   7 __author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"
   8 __copyright__  = "Copyright 2012-2017, Lluís Vilanova <vilanova@ac.upc.edu>"
   9 __license__    = "GPL version 2 or (at your option) any later version"
  10
  11 __maintainer__ = "Stefan Hajnoczi"
  12 __email__      = "stefanha@redhat.com"
  13
  14
  15 from tracetool import out
  16
  17
  18 PUBLIC = True
  19
  20
  21 def is_string(arg):
  22     strtype = ('const char*', 'char*', 'const char *', 'char *')
  23     arg_strip = arg.lstrip()
  24     if arg_strip.startswith(strtype) and arg_strip.count('*') == 1:
  25         return True
  26     else:
  27         return False
  28
  29
  30 def generate_h_begin(events, group):
  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, group):
  39     out('    _simple_%(api)s(%(args)s);',
  40         api=event.api(),
  41         args=", ".join(event.args.names()))
  42
  43
  44 def generate_h_backend_dstate(event, group):
  45     out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
  46         event_id="TRACE_" + event.name.upper())
  47
  48
  49 def generate_c_begin(events, group):
  50     out('#include "qemu/osdep.h"',
  51         '#include "trace/control.h"',
  52         '#include "trace/simple.h"',
  53         '')
  54
  55
  56 def generate_c(event, group):
  57     out('void _simple_%(api)s(%(args)s)',
  58         '{',
  59         '    TraceBufferRecord rec;',
  60         api=event.api(),
  61         args=event.args)
  62     sizes = []
  63     for type_, name in event.args:
  64         if is_string(type_):
  65             out('    size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
  66                 name=name)
  67             strsizeinfo = "4 + arg%s_len" % name
  68             sizes.append(strsizeinfo)
  69         else:
  70             sizes.append("8")
  71     sizestr = " + ".join(sizes)
  72     if len(event.args) == 0:
  73         sizestr = '0'
  74
  75     event_id = 'TRACE_' + event.name.upper()
  76     if "vcpu" in event.properties:
  77         # already checked on the generic format code
  78         cond = "true"
  79     else:
  80         cond = "trace_event_get_state(%s)" % event_id
  81
  82     out('',
  83         '    if (!%(cond)s) {',
  84         '        return;',
  85         '    }',
  86         '',
  87         '    if (trace_record_start(&rec, %(event_obj)s.id, %(size_str)s)) {',
  88         '        return; /* Trace Buffer Full, Event Dropped ! */',
  89         '    }',
  90         cond=cond,
  91         event_obj=event.api(event.QEMU_EVENT),
  92         size_str=sizestr)
  93
  94     if len(event.args) > 0:
  95         for type_, name in event.args:
  96             # string
  97             if is_string(type_):
  98                 out('    trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
  99                     name=name)
 100             # pointer var (not string)
 101             elif type_.endswith('*'):
 102                 out('    trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
 103                     name=name)
 104             # primitive data type
 105             else:
 106                 out('    trace_record_write_u64(&rec, (uint64_t)%(name)s);',
 107                    name=name)
 108
 109     out('    trace_record_finish(&rec);',
 110         '}',
 111         '')