Commit 7f1b588f20d027730676e627713ae3bbf6baab04 ("trace: emit name <-> ID mapping in simpletrace header") broke the SystemTap flight recorder because event mapping records may no longer be present in the ring buffer when the trace is analyzed. This means simpletrace.py --no-header does not know the event ID mapping needed to pretty-print the trace.
Instead of numbering events dynamically, use a static event ID mapping as dictated by the event order in the trace-events-all file. The simpletrace.py script also uses trace-events-all so the next patch will fix the simpletrace.py --no-header option to take advantage of this knowledge. Cc: Daniel P. Berrange <berra...@redhat.com> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> --- scripts/tracetool/format/simpletrace_stap.py | 36 ++++++++++++---------------- 1 file changed, 15 insertions(+), 21 deletions(-) diff --git a/scripts/tracetool/format/simpletrace_stap.py b/scripts/tracetool/format/simpletrace_stap.py index 144b704bcd..6cfdc32867 100644 --- a/scripts/tracetool/format/simpletrace_stap.py +++ b/scripts/tracetool/format/simpletrace_stap.py @@ -22,33 +22,18 @@ def global_var_name(name): return probeprefix().replace(".", "_") + "_" + name def generate(events, backend, group): - id_map = global_var_name("event_name_to_id_map") - next_id = global_var_name("event_next_id") - map_func = global_var_name("simple_trace_map_event") + id_map = global_var_name("id_map") + out('/* This file is autogenerated by tracetool, do not edit. */', '', 'global %(id_map)s', - 'global %(next_id)s', - 'function %(map_func)s(name)', '', - '{', - ' if (!([name] in %(id_map)s)) {', - ' %(id_map)s[name] = %(next_id)s', - ' name_len = strlen(name)', - ' printf("%%8b%%8b%%4b%%.*s", 0, ', - ' %(next_id)s, name_len, name_len, name)', - ' %(next_id)s = %(next_id)s + 1', - ' }', - ' return %(id_map)s[name]', - '}', 'probe begin', '{', ' printf("%%8b%%8b%%8b", 0xffffffffffffffff, 0xf2b177cb0aa429b4, 4)', '}', '', - id_map=id_map, - next_id=next_id, - map_func=map_func) + id_map=id_map) for event_id, e in enumerate(events): if 'disable' in e.properties: @@ -56,11 +41,20 @@ def generate(events, backend, group): out('probe %(probeprefix)s.simpletrace.%(name)s = %(probeprefix)s.%(name)s ?', '{', - ' id = %(map_func)s("%(name)s")', probeprefix=probeprefix(), - map_func=map_func, name=e.name) + out(' if (!(["%(name)s"] in %(id_map)s)) {', + ' %(id_map)s["%(name)s"] = 1', + ' printf("%%8b%%8b%%4b%%.*s", 0, ', + ' %(event_id)s, %(name_len)s, %(name_len)s,', + ' "%(name)s")', + ' }', + id_map=id_map, + name=e.name, + name_len=len(e.name), + event_id=event_id) + # Calculate record size sizes = ['24'] # sizeof(TraceRecord) for type_, name in e.args: @@ -77,7 +71,7 @@ def generate(events, backend, group): sizestr = ' + '.join(sizes) # Generate format string and value pairs for record header and arguments - fields = [('8b', 'id'), + fields = [('8b', str(event_id)), ('8b', 'gettimeofday_ns()'), ('4b', sizestr), ('4b', 'pid()')] -- 2.13.4