[PATCH v3 04/12] perf evsel: apply evsel__set_config_if_unset() to all config fields

James Clark
2025-12-12T15:32:50Z

Misleadingly, evsel__set_config_if_unset() only works with the config
field and not config1, config2, etc. This is fine at the moment because
all users of it happen to operate on bits that are in that config field.
Fix it before there are any new users of the function which operate on
bits in different config fields.

In theory it's also possible for a driver to move an existing bit to
another config field and this fixes that scenario too, although this
hasn't happened yet either.

Signed-off-by: James Clark <james.clark@linaro.org>
---
tools/perf/util/pmu.c | 37 +++++++++++++++++++++++++++++++++++--
1 file changed, 35 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index e02f74d4020c151082ecc434c29c0ec4c2c9b2c8..514cba91f5d99b399d2d6a1e350971660c54a9fc 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -146,6 +146,8 @@ struct perf_pmu_format {
static int pmu_aliases_parse(struct perf_pmu *pmu);
static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
bool zero);
+static struct perf_pmu_format *pmu_find_format(const struct list_head *formats,
+ const char *name);

static struct perf_pmu_format *perf_pmu__new_format(struct list_head *list, char *name)
{
@@ -1387,7 +1389,38 @@ void evsel__set_config_if_unset(struct perf_pmu *pmu, struct evsel *evsel,
const char *config_name, u64 val)
{
u64 user_bits = 0, bits;
- struct evsel_config_term *term = evsel__get_config_term(evsel, USR_CHG_CONFIG);
+ struct evsel_config_term *term;
+ struct perf_pmu_format *format = pmu_find_format(&pmu->format, config_name);
+ __u64 *vp;
+
+ if (!format)
+ return;
+
+ switch (format->value) {
+ case PERF_PMU_FORMAT_VALUE_CONFIG:
+ term = evsel__get_config_term(evsel, USR_CHG_CONFIG);
+ vp = &evsel->core.attr.config;
+ break;
+ case PERF_PMU_FORMAT_VALUE_CONFIG1:
+ term = evsel__get_config_term(evsel, USR_CHG_CONFIG1);
+ vp = &evsel->core.attr.config1;
+ break;
+ case PERF_PMU_FORMAT_VALUE_CONFIG2:
+ term = evsel__get_config_term(evsel, USR_CHG_CONFIG2);
+ vp = &evsel->core.attr.config2;
+ break;
+ case PERF_PMU_FORMAT_VALUE_CONFIG3:
+ term = evsel__get_config_term(evsel, USR_CHG_CONFIG3);
+ vp = &evsel->core.attr.config3;
+ break;
+ case PERF_PMU_FORMAT_VALUE_CONFIG4:
+ term = evsel__get_config_term(evsel, USR_CHG_CONFIG4);
+ vp = &evsel->core.attr.config4;
+ break;
+ default:
+ pr_err("Unknown format value: %d\n", format->value);
+ return;
+ }

if (term)
user_bits = term->val.cfg_chg;
@@ -1399,7 +1432,7 @@ void evsel__set_config_if_unset(struct perf_pmu *pmu, struct evsel *evsel,
return;

/* Otherwise replace it */
- pmu_format_value(&bits, val, &evsel->core.attr.config, /*zero=*/true);
+ pmu_format_value(&bits, val, vp, /*zero=*/true);
}

static struct perf_pmu_format *

--
2.34.1