qemu/scripts/tracetool/backend/simple.py
Daniel P. Berrange ef4c9fc854 trace: remove the TraceEventID and TraceEventVCPUID enums
The TraceEventID and TraceEventVCPUID enums constants are
no longer actually used for anything critical.

The TRACE_EVENT_COUNT limit is used to determine the size
of the TraceEvents array, and can be removed if we just
NULL terminate the array instead.

The TRACE_VCPU_EVENT_COUNT limit is used as a magic value
for marking non-vCPU events, and also for declaring the
size of the trace dstate mask in the CPUState struct.
The former usage can be replaced by a dedicated constant
TRACE_EVENT_VCPU_NONE, defined as (uint32_t)-1. For the
latter usage, we can simply define a constant for the
number of VCPUs, avoiding the need for the full enum.

The only other usages of the enum values can be replaced
by accesing the id/vcpu_id fields via the named TraceEvent
structs.

Reviewed-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1475588159-30598-11-git-send-email-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-10-12 09:35:54 +02:00

108 lines
2.9 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Simple built-in backend.
"""
__author__ = "Lluís Vilanova <vilanova@ac.upc.edu>"
__copyright__ = "Copyright 2012-2014, Lluís Vilanova <vilanova@ac.upc.edu>"
__license__ = "GPL version 2 or (at your option) any later version"
__maintainer__ = "Stefan Hajnoczi"
__email__ = "stefanha@linux.vnet.ibm.com"
from tracetool import out
PUBLIC = True
def is_string(arg):
strtype = ('const char*', 'char*', 'const char *', 'char *')
if arg.lstrip().startswith(strtype):
return True
else:
return False
def generate_h_begin(events):
for event in events:
out('void _simple_%(api)s(%(args)s);',
api=event.api(),
args=event.args)
out('')
def generate_h(event):
out(' _simple_%(api)s(%(args)s);',
api=event.api(),
args=", ".join(event.args.names()))
def generate_c_begin(events):
out('#include "qemu/osdep.h"',
'#include "trace.h"',
'#include "trace/control.h"',
'#include "trace/simple.h"',
'')
def generate_c(event):
out('void _simple_%(api)s(%(args)s)',
'{',
' TraceBufferRecord rec;',
api=event.api(),
args=event.args)
sizes = []
for type_, name in event.args:
if is_string(type_):
out(' size_t arg%(name)s_len = %(name)s ? MIN(strlen(%(name)s), MAX_TRACE_STRLEN) : 0;',
name=name)
strsizeinfo = "4 + arg%s_len" % name
sizes.append(strsizeinfo)
else:
sizes.append("8")
sizestr = " + ".join(sizes)
if len(event.args) == 0:
sizestr = '0'
event_id = 'TRACE_' + event.name.upper()
if "vcpu" in event.properties:
# already checked on the generic format code
cond = "true"
else:
cond = "trace_event_get_state(%s)" % event_id
out('',
' if (!%(cond)s) {',
' return;',
' }',
'',
' if (trace_record_start(&rec, %(event_obj)s.id, %(size_str)s)) {',
' return; /* Trace Buffer Full, Event Dropped ! */',
' }',
cond=cond,
event_obj=event.api(event.QEMU_EVENT),
size_str=sizestr)
if len(event.args) > 0:
for type_, name in event.args:
# string
if is_string(type_):
out(' trace_record_write_str(&rec, %(name)s, arg%(name)s_len);',
name=name)
# pointer var (not string)
elif type_.endswith('*'):
out(' trace_record_write_u64(&rec, (uintptr_t)(uint64_t *)%(name)s);',
name=name)
# primitive data type
else:
out(' trace_record_write_u64(&rec, (uint64_t)%(name)s);',
name=name)
out(' trace_record_finish(&rec);',
'}',
'')