On Mon, Sep 18, 2023 at 4:52 AM Jing Zhang <renyu.zj@xxxxxxxxxxxxxxxxx> wrote:
>
> The jevent "Compat" is used for uncore PMU alias or metric definitions.
>
> The same PMU driver has different PMU identifiers due to different
> hardware versions and types, but they may have some common PMU event.
> Since a Compat value can only match one identifier, when adding the
> same event alias to PMUs with different identifiers, each identifier
> needs to be defined once, which is not streamlined enough.
>
> So let "Compat" support using regular expression to match identifiers
> for uncore PMU alias. For example, if the "Compat" value is set to
> "43401|43c01", it would be able to match PMU identifiers such as "43401"
> or "43c01", which correspond to CMN600_r0p0 or CMN700_r0p0.
>
> Signed-off-by: Jing Zhang <renyu.zj@xxxxxxxxxxxxxxxxx>
> ---
> tools/perf/util/pmu.c | 23 +++++++++++++++++++++--
> tools/perf/util/pmu.h | 1 +
> 2 files changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index e215985..7e2242f 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -28,6 +28,7 @@
> #include "strbuf.h"
> #include "fncache.h"
> #include "util/evsel_config.h"
> +#include <regex.h>
>
> struct perf_pmu perf_pmu__fake = {
> .name = "fake",
> @@ -875,6 +876,24 @@ static bool pmu_uncore_alias_match(const char *pmu_name, const char *name)
> return res;
> }
>
> +bool pmu_uncore_identifier_match(const char *compat, const char *id)
> +{
> + regex_t re;
> + regmatch_t pmatch[1];
> + int match;
> +
> + if (regcomp(&re, compat, REG_EXTENDED) != 0) {
> + /* Warn unable to generate match particular string. */
> + pr_info("Invalid regular expression %s\n", compat);
> + return false;
> + }
> +
> + match = !regexec(&re, id, 1, pmatch, 0);
I wonder if we can make the regular expressions like
"^(434|436|43c|43a)" more like "(434|436|43c|43a).*", so that we fully
match the id string, by here doing:
if (match) {
/* Ensure a full match. */
match = pmatch[0].rm_so == 0 && pmatch[0].rm_eo == strlen(id);
}
I think longer term we can use jevents.py to generate a pmu-events.l,
which would have a contents something like:
(434|436|43c|43a).* { return PMU_....;}
That should make the matching faster but may add some restrictions
onto the regular expression.
Thanks,
Ian
> + regfree(&re);
> +
> + return match;
> +}
> +
> static int pmu_add_cpu_aliases_map_callback(const struct pmu_event *pe,
> const struct pmu_events_table *table __maybe_unused,
> void *vdata)
> @@ -915,8 +934,8 @@ static int pmu_add_sys_aliases_iter_fn(const struct pmu_event *pe,
> if (!pe->compat || !pe->pmu)
> return 0;
>
> - if (!strcmp(pmu->id, pe->compat) &&
> - pmu_uncore_alias_match(pe->pmu, pmu->name)) {
> + if (pmu_uncore_alias_match(pe->pmu, pmu->name) &&
> + pmu_uncore_identifier_match(pe->compat, pmu->id)) {
> perf_pmu__new_alias(pmu,
> pe->name,
> pe->desc,
> diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
> index bd5d804..fc155ce 100644
> --- a/tools/perf/util/pmu.h
> +++ b/tools/perf/util/pmu.h
> @@ -240,6 +240,7 @@ void pmu_add_cpu_aliases_table(struct perf_pmu *pmu,
> char *perf_pmu__getcpuid(struct perf_pmu *pmu);
> const struct pmu_events_table *pmu_events_table__find(void);
> const struct pmu_metrics_table *pmu_metrics_table__find(void);
> +bool pmu_uncore_identifier_match(const char *compat, const char *id);
>
> int perf_pmu__convert_scale(const char *scale, char **end, double *sval);
>
> --
> 1.8.3.1
>
