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 from tracetool import out
  16
  17
  18 PUBLIC = True
  19
  20
  21 def generate_h_begin(events, group):
  22     out('#include "trace/ftrace.h"',
  23         '')
  24
  25
  26 def generate_h(event, group):
  27     argnames = ", ".join(event.args.names())
  28     if len(event.args) > 0:
  29         argnames = ", " + argnames
  30
  31     out('    {',
  32         '        char ftrace_buf[MAX_TRACE_STRLEN];',
  33         '        int unused __attribute__ ((unused));',
  34         '        int trlen;',
  35         '        if (trace_event_get_state(%(event_id)s)) {',
  36         '#line %(event_lineno)d "%(event_filename)s"',
  37         '            trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
  38         '                             "%(name)s " %(fmt)s "\\n" %(argnames)s);',
  39         '#line %(out_next_lineno)d "%(out_filename)s"',
  40         '            trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);',
  41         '            unused = write(trace_marker_fd, ftrace_buf, trlen);',
  42         '        }',
  43         '    }',
  44         name=event.name,
  45         args=event.args,
  46         event_id="TRACE_" + event.name.upper(),
  47         event_lineno=event.lineno,
  48         event_filename=event.filename,
  49         fmt=event.fmt.rstrip("\n"),
  50         argnames=argnames)
  51
  52
  53 def 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())