scripts/tracetool/backend/ftrace.py

   1 # -*- coding: utf-8 -*-
   2
   3 """
   4 Ftrace built-in backend.
   5 """
   6
   7 __author__     = "Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>"
   8 __copyright__  = "Copyright (C) 2013 Hitachi, Ltd."
   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 import os.path
  16
  17 from tracetool import out
  18
  19
  20 PUBLIC = True
  21
  22
  23 def generate_h_begin(events, group):
  24     out('#include "trace/ftrace.h"',
  25         '')
  26
  27
  28 def generate_h(event, group):
  29     argnames = ", ".join(event.args.names())
  30     if len(event.args) > 0:
  31         argnames = ", " + argnames
  32
  33     out('    {',
  34         '        char ftrace_buf[MAX_TRACE_STRLEN];',
  35         '        int unused __attribute__ ((unused));',
  36         '        int trlen;',
  37         '        if (trace_event_get_state(%(event_id)s)) {',
  38         '#line %(event_lineno)d "%(event_filename)s"',
  39         '            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
  40         '                             "%(name)s " %(fmt)s "\\n" %(argnames)s);',
  41         '#line %(out_next_lineno)d "%(out_filename)s"',
  42         '            trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);',
  43         '            unused = write(trace_marker_fd, ftrace_buf, trlen);',
  44         '        }',
  45         '    }',
  46         name=event.name,
  47         args=event.args,
  48         event_id="TRACE_" + event.name.upper(),
  49         event_lineno=event.lineno,
  50         event_filename=os.path.relpath(event.filename),
  51         fmt=event.fmt.rstrip("\n"),
  52         argnames=argnames)
  53
  54
  55 def generate_h_backend_dstate(event, group):
  56     out('    trace_event_get_state_dynamic_by_id(%(event_id)s) || \\',
  57         event_id="TRACE_" + event.name.upper())