On 06/15/2018 10:12 AM, Jiri Olsa wrote: > On Thu, Jun 14, 2018 at 08:53:14AM -0500, Paul Clarke wrote: > > SNIP > >>> + if (ret) >>> + ret += scnprintf(newval + ret, sizeof(newval) - ret, >>> + ","); >>> + if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) >>> + ret += scnprintf(newval + ret, sizeof(newval) - ret, >>> + "%s=%#x", term->config, term->val.num); >>> + else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) >>> + ret += scnprintf(newval + ret, sizeof(newval) - ret, >>> + "%s=%s", term->config, term->val.str); >> >> If we exceed 256, we just suddenly terminate the rebuilding without >> reporting any issues. >> >>> + } >>> + >>> alias->name = strdup(name); >>> if (dir) { >>> /* >>> @@ -285,7 +308,7 @@ static int __perf_pmu__new_alias(struct list_head >>> *list, char *dir, char *name, >>> snprintf(alias->unit, sizeof(alias->unit), "%s", unit); >>> } >>> alias->per_pkg = perpkg && sscanf(perpkg, "%d", &num) == 1 && num == 1; >>> - alias->str = strdup(val); >>> + alias->str = strdup(newval); > > hum, how is newval different from val? AFAICS it's the same >
Not really, depends on the platform, here is some debug output from s390: root@s35lp76 perf]# ./perf stat -e tx_nc_tend -- ~/mytesttx 1 >/tmp/111 Performance counter stats for '/root/mytesttx 1': 1 tx_nc_tend 0.001050150 seconds time elapsed [root@s35lp76 perf]# fgrep -i tx_nc_tend /tmp/111 __perf_pmu__new_alias TX_NC_TEND val:event=0x008d newval:event=0x8d __perf_pmu__new_alias tx_nc_tend val:event=0x8d newval:event=0x8d TX_NC_TEND 1 rc 8 [root@s35lp76 perf]# On s390 the events in the PMU sysfs file are printed with leading zeroes. This means the strcmp() of alias->str differs, but the contents is logically identical. (Same of some files contains spaces). Thats why I do the rewrite of val into newval. The alias name does not match too, but we use strcasecmp() to ignore case. Hope this helps. -- Thomas Richter, Dept 3303, IBM s390 Linux Development, Boeblingen, Germany -- Vorsitzende des Aufsichtsrats: Martina Koederitz Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen / Registergericht: Amtsgericht Stuttgart, HRB 243294