perf pmu: Add proper error handling to print_pmu_events()

It was silently returning or printing "(null)" when no memory was
available at various points. Fix it by checking and warning the user
when that happens.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jean Pihet <jean.pihet@linaro.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-835udmf66x9nza504cu6irz9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2014-10-24 10:25:09 -03:00
parent 46b1fa85ff
commit 7e4772dc99

View file

@ -753,9 +753,9 @@ void print_pmu_events(const char *event_glob, bool name_only)
if (pmu->selectable)
len++;
}
aliases = malloc(sizeof(char *) * len);
aliases = zalloc(sizeof(char *) * len);
if (!aliases)
return;
goto out_enomem;
pmu = NULL;
j = 0;
while ((pmu = perf_pmu__scan(pmu)) != NULL) {
@ -768,16 +768,20 @@ void print_pmu_events(const char *event_glob, bool name_only)
(!is_cpu && strglobmatch(alias->name,
event_glob))))
continue;
aliases[j] = name;
if (is_cpu && !name_only)
aliases[j] = format_alias_or(buf, sizeof(buf),
pmu, alias);
aliases[j] = strdup(aliases[j]);
name = format_alias_or(buf, sizeof(buf), pmu, alias);
aliases[j] = strdup(name);
if (aliases[j] == NULL)
goto out_enomem;
j++;
}
if (pmu->selectable) {
scnprintf(buf, sizeof(buf), "%s//", pmu->name);
aliases[j] = strdup(buf);
char *s;
if (asprintf(&s, "%s//", pmu->name) < 0)
goto out_enomem;
aliases[j] = s;
j++;
}
}
@ -789,12 +793,20 @@ void print_pmu_events(const char *event_glob, bool name_only)
continue;
}
printf(" %-50s [Kernel PMU event]\n", aliases[j]);
zfree(&aliases[j]);
printed++;
}
if (printed)
printf("\n");
free(aliases);
out_free:
for (j = 0; j < len; j++)
zfree(&aliases[j]);
zfree(&aliases);
return;
out_enomem:
printf("FATAL: not enough memory to print PMU events\n");
if (aliases)
goto out_free;
}
bool pmu_have_event(const char *pname, const char *name)