xref: /qemu/scripts/tracetool/backend/simple.py (revision b4ff3cf34fa09b28a480870b98377bac183833c8) 
1# -*- coding: utf-8 -*-
2
3"""
4Simple 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
15from tracetool import out
16
17
18PUBLIC = True
19
20
21def 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
30def 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
38def generate_h(event, group):
39    event_id = 'TRACE_' + event.name.upper()
40    if "vcpu" in event.properties:
41        # already checked on the generic format code
42        cond = "true"
43    else:
44        cond = "trace_event_get_state(%s)" % event_id
45    out('    if (%(cond)s) {',
46        '        _simple_%(api)s(%(args)s);',
47        '    }',
48        api=event.api(),
49        cond=cond,
50        args=", ".join(event.args.names()))
51
52
53def generate_h_backend_dstate(event, group):
54    out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
55        event_id="TRACE_" + event.name.upper())
56
57
58def generate_c_begin(events, group):
59    out('#include "qemu/osdep.h"',
60        '#include "trace/control.h"',
61        '#include "trace/simple.h"',
62        '')
63
64
65def generate_c(event, group):
66    out('void _simple_%(api)s(%(args)s)',
67        '{',
68        '    TraceBufferRecord rec;',
69        api=event.api(),
70        args=event.args)
71    sizes = []
72    for type_, name in event.args:
73        if is_string(type_):
74            out('    size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
75                name=name)
76            strsizeinfo = "4 + arg%s_len" % name
77            sizes.append(strsizeinfo)
78        else:
79            sizes.append("8")
80    sizestr = " + ".join(sizes)
81    if len(event.args) == 0:
82        sizestr = '0'
83
84    out('',
85        '    if (trace_record_start(&rec, %(event_obj)s.id, %(size_str)s)) {',
86        '        return; /* Trace Buffer Full, Event Dropped ! */',
87        '    }',
88        event_obj=event.api(event.QEMU_EVENT),
89        size_str=sizestr)
90
91    if len(event.args) > 0:
92        for type_, name in event.args:
93            # string
94            if is_string(type_):
95                out('    trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
96                    name=name)
97            # pointer var (not string)
98            elif type_.endswith('*'):
99                out('    trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
100                    name=name)
101            # primitive data type
102            else:
103                out('    trace_record_write_u64(&rec, (uint64_t)%(name)s);',
104                   name=name)
105
106    out('    trace_record_finish(&rec);',
107        '}',
108        '')
109