On Wed, Sep 28, 2016 at 02:08:14PM +0100, Daniel P. Berrange wrote:
> def read_trace_records(edict, fobj):
> """Deserialize trace records from a file, yielding record tuples
> (event_num, timestamp, pid, arg1, ..., arg6)."""
> + idtoname = {
> + dropped_event_id: "dropped"
> + }
> while True:
> - rec = read_record(edict, fobj)
> - if rec is None:
> + t = fobj.read(8)
> + if len(t) == 0:
> break
>
> - yield rec
> + (rectype, ) = struct.unpack('=Q', t)
> + if rectype == record_type_mapping:
> + mapping = get_mapping(fobj)
> + idtoname[mapping[0]] = mapping[1]
Unpacking the tuple makes the code easier to read:
event_id, name = get_mapping(fobj)
idtoname[event_id] = name
> diff --git a/scripts/tracetool/format/simpletrace_stap.py
> b/scripts/tracetool/format/simpletrace_stap.py
> index 7e44bc1..ac3580f 100644
> --- a/scripts/tracetool/format/simpletrace_stap.py
> +++ b/scripts/tracetool/format/simpletrace_stap.py
> @@ -21,6 +21,25 @@ from tracetool.format.stap import stap_escape
>
> def generate(events, backend):
> out('/* This file is autogenerated by tracetool, do not edit. */',
> + '',
> + 'global event_name_to_id_map',
> + 'global event_next_id',
> + 'function simple_trace_map_event(name)',
> + '',
> + '{',
> + ' if (!([name] in event_name_to_id_map)) {',
> + ' event_name_to_id_map[name] = event_next_id',
> + ' name_len = strlen(name)',
> + ' printf("%%8b%%8b%%4b%%.*s", 0, ',
> + ' event_next_id, name_len, name_len, name)',
> + ' event_next_id = event_next_id + 1',
> + ' }',
> + ' return event_name_to_id_map[name]',
> + '}',
> + 'probe begin',
> + '{',
> + ' printf("%%8b%%8b%%8b", 0xffffffffffffffff, 0xf2b177cb0aa429b4,
> 4)',
The reason the SystemTap script doesn't emit a header is because it was
designed for trace flight-recorder mode. There's probably no harm in
emitting the header. Flight-recorder users will still have to use
--no-header though.
signature.asc
Description: PGP signature
