On 06/14/2018 06:48 AM, Thomas Richter wrote:
> PMU alias definitions in sysfs files may have spaces, newlines
> and number with leading zeroes. Same alias definitions may
> also appear in JSON files without spaces, etc.
> 
> Scan alias definitions and remove leading zeroes, spaces,
> newlines, etc and rebuild string to make alias->str member
> comparable.
> 
> s390 for example  has terms specified as
> event=0x0091 (read from files ../<PMU>/events/<FILE>
> and terms specified as event=0x91 (read from JSON files).
> 
> Signed-off-by: Thomas Richter <tmri...@linux.ibm.com>
> ---
>  tools/perf/util/pmu.c | 25 ++++++++++++++++++++++++-
>  1 file changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index 26c79a9c4142..da8f243743d3 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -241,9 +241,11 @@ static int __perf_pmu__new_alias(struct list_head *list, 
> char *dir, char *name,
>                                char *metric_expr,
>                                char *metric_name)
>  {
> +     struct parse_events_term *term;
>       struct perf_pmu_alias *alias;
>       int ret;
>       int num;
> +     char newval[256];

How was 256 chosen?

> 
>       alias = malloc(sizeof(*alias));
>       if (!alias)
> @@ -262,6 +264,27 @@ static int __perf_pmu__new_alias(struct list_head *list, 
> char *dir, char *name,
>               return ret;
>       }
> 
> +     /* Scan event and remove leading zeroes, spaces, newlines, some
> +      * platforms have terms specified as
> +      * event=0x0091 (read from files ../<PMU>/events/<FILE>
> +      * and terms specified as event=0x91 (read from JSON files).
> +      *
> +      * Rebuild string to make alias->str member comparable.
> +      */
> +     memset(newval, 0, sizeof(newval));
> +     ret = 0;
> +     list_for_each_entry(term, &alias->terms, list) {
> +             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);
> 
>       list_add_tail(&alias->list, list);
> 

PC

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