perf scripting engines: Iterate on tep event arrays directly

Instead of calling a useless (and broken) helper function to get the
next event of a tep event array, just get the array directly and iterate
over it.

Note, the broken part was from trace_find_next_event() which after this
will no longer be used, and can be removed.

Committer notes:

This fixes a segfault when generating python scripts from perf.data
files with multiple tracepoint events, i.e. the following use case is
fixed by this patch:

  # perf record -e sched:* sleep 1
  [ perf record: Woken up 31 times to write data ]
  [ perf record: Captured and wrote 0.031 MB perf.data (9 samples) ]
  # perf script -g python
  Segmentation fault (core dumped)
  #

Reported-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lkml.kernel.org/r/20191017153733.630cd5eb@gandalf.local.home
Link: http://lore.kernel.org/lkml/20191017210636.061448713@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Steven Rostedt (VMware) 2019-10-17 17:05:22 -04:00 committed by Arnaldo Carvalho de Melo
parent 362222f877
commit a5e05abc6b
2 changed files with 13 additions and 4 deletions

View File

@ -539,10 +539,11 @@ static int perl_stop_script(void)
static int perl_generate_script(struct tep_handle *pevent, const char *outfile)
{
int i, not_first, count, nr_events;
struct tep_event **all_events;
struct tep_event *event = NULL;
struct tep_format_field *f;
char fname[PATH_MAX];
int not_first, count;
FILE *ofp;
sprintf(fname, "%s.pl", outfile);
@ -603,8 +604,11 @@ sub print_backtrace\n\
}\n\n\
");
nr_events = tep_get_events_count(pevent);
all_events = tep_list_events(pevent, TEP_EVENT_SORT_ID);
while ((event = trace_find_next_event(pevent, event))) {
for (i = 0; all_events && i < nr_events; i++) {
event = all_events[i];
fprintf(ofp, "sub %s::%s\n{\n", event->system, event->name);
fprintf(ofp, "\tmy (");

View File

@ -1687,10 +1687,11 @@ static int python_stop_script(void)
static int python_generate_script(struct tep_handle *pevent, const char *outfile)
{
int i, not_first, count, nr_events;
struct tep_event **all_events;
struct tep_event *event = NULL;
struct tep_format_field *f;
char fname[PATH_MAX];
int not_first, count;
FILE *ofp;
sprintf(fname, "%s.py", outfile);
@ -1735,7 +1736,11 @@ static int python_generate_script(struct tep_handle *pevent, const char *outfile
fprintf(ofp, "def trace_end():\n");
fprintf(ofp, "\tprint(\"in trace_end\")\n\n");
while ((event = trace_find_next_event(pevent, event))) {
nr_events = tep_get_events_count(pevent);
all_events = tep_list_events(pevent, TEP_EVENT_SORT_ID);
for (i = 0; all_events && i < nr_events; i++) {
event = all_events[i];
fprintf(ofp, "def %s__%s(", event->system, event->name);
fprintf(ofp, "event_name, ");
fprintf(ofp, "context, ");