This will be used by aux PMUs to read an already written value for
configuring their events and for also testing.

Its helper pmu_format_unpack() does the opposite of the existing
pmu_format_value() so rename that one to pmu_format_pack() so it's clear
how they are related.

Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/util/evsel.h |  2 ++
 tools/perf/util/pmu.c   | 77 ++++++++++++++++++++++++++++++++++++++++++-------
 2 files changed, 68 insertions(+), 11 deletions(-)

diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index a08130ff2e47a887b19f6c47bfa9f51e0c40d226..092904a61ec7afdc59253f9b78a9fe8b7cb5bfa7 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h

@@ -575,6 +575,8 @@ void evsel__uniquify_counter(struct evsel *counter);
        ((((src) >> (pos)) & ((1ull << (size)) - 1)) << (63 - ((pos) + (size) - 1)))

 u64 evsel__bitfield_swap_branch_flags(u64 value);
+int evsel__get_config_val(struct perf_pmu *pmu, struct evsel *evsel,
+                         const char *config_name, u64 *val);
 void evsel__set_config_if_unset(struct perf_pmu *pmu, struct evsel *evsel,
                                const char *config_name, u64 val);

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 514cba91f5d99b399d2d6a1e350971660c54a9fc..ef7358ad1fb955f29f2e68b3d0ce711754e4d67c 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c

@@ -144,8 +144,8 @@ 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 void pmu_format_pack(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);

@@ -1377,6 +1377,61 @@ bool evsel__is_aux_event(const struct evsel *evsel)
        return pmu && pmu->auxtrace;
 }

+/*
+ * Unpacks a raw config[n] value using the sparse bitfield that defines a
+ * format attr. For example "config1:1,6-7,44" defines a 4 bit value across non
+ * contiguous bits and this function returns those 4 bits as a value.
+ */
+static u64 pmu_format_unpack(u64 format, u64 config_val)
+{
+       int val_bit = 0;
+       u64 res = 0;
+       int fmt_bit;
+
+       for_each_set_bit(fmt_bit, &format, PERF_PMU_FORMAT_BITS) {
+               if (test_bit(fmt_bit, &config_val))
+                       res |= BIT_ULL(val_bit);
+
+               val_bit++;
+       }
+       return res;
+}
+
+int evsel__get_config_val(struct perf_pmu *pmu, struct evsel *evsel,
+                         const char *config_name, u64 *val)

+{
+       struct perf_pmu_format *format = pmu_find_format(&pmu->format, config_name);
+       u64 bits = perf_pmu__format_bits(pmu, config_name);
+
+       if (!format || !bits) {
+               pr_err("Unknown/empty format name: %s\n", config_name);
+               *val = 0;
+               return -EINVAL;
+       }
+
+       switch (format->value) {
+       case PERF_PMU_FORMAT_VALUE_CONFIG:
+               *val = pmu_format_unpack(bits, evsel->core.attr.config);
+               return 0;
+       case PERF_PMU_FORMAT_VALUE_CONFIG1:
+               *val = pmu_format_unpack(bits, evsel->core.attr.config1);
+               return 0;
+       case PERF_PMU_FORMAT_VALUE_CONFIG2:
+               *val = pmu_format_unpack(bits, evsel->core.attr.config2);
+               return 0;
+       case PERF_PMU_FORMAT_VALUE_CONFIG3:
+               *val = pmu_format_unpack(bits, evsel->core.attr.config3);
+               return 0;
+       case PERF_PMU_FORMAT_VALUE_CONFIG4:
+               *val = pmu_format_unpack(bits, evsel->core.attr.config4);
+               return 0;
+       default:
+               pr_err("Unknown format value: %d\n", format->value);
+               *val = 0;
+               return -EINVAL;
+       }
+}
+
 /*
  * Set @config_name to @val as long as the user hasn't already set or cleared it
  * by passing a config term on the command line.

@@ -1432,7 +1487,7 @@ void evsel__set_config_if_unset(struct perf_pmu *pmu, struct evsel *evsel,
                return;

        /* Otherwise replace it */
-       pmu_format_value(&bits, val, vp, /*zero=*/true);
+       pmu_format_pack(&bits, val, vp, /*zero=*/true);
 }

 static struct perf_pmu_format *

@@ -1477,8 +1532,8 @@ int perf_pmu__format_type(struct perf_pmu *pmu, const char *name)
  * Sets value based on the format definition (format parameter)
  * and unformatted value (value parameter).
  */
-static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
-                            bool zero)
+static void pmu_format_pack(unsigned long *format, __u64 value, __u64 *v,
+                           bool zero)
 {
        unsigned long fbit, vbit;

@@ -1595,23 +1650,23 @@ static int pmu_config_term(const struct perf_pmu *pmu,
                switch (term->type_term) {
                case PARSE_EVENTS__TERM_TYPE_CONFIG:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
-                       pmu_format_value(bits, term->val.num, &attr->config, zero);
+                       pmu_format_pack(bits, term->val.num, &attr->config, zero);
                        break;
                case PARSE_EVENTS__TERM_TYPE_CONFIG1:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
-                       pmu_format_value(bits, term->val.num, &attr->config1, zero);
+                       pmu_format_pack(bits, term->val.num, &attr->config1, zero);
                        break;
                case PARSE_EVENTS__TERM_TYPE_CONFIG2:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
-                       pmu_format_value(bits, term->val.num, &attr->config2, zero);
+                       pmu_format_pack(bits, term->val.num, &attr->config2, zero);
                        break;
                case PARSE_EVENTS__TERM_TYPE_CONFIG3:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
-                       pmu_format_value(bits, term->val.num, &attr->config3, zero);
+                       pmu_format_pack(bits, term->val.num, &attr->config3, zero);
                        break;
                case PARSE_EVENTS__TERM_TYPE_CONFIG4:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);
-                       pmu_format_value(bits, term->val.num, &attr->config4, zero);
+                       pmu_format_pack(bits, term->val.num, &attr->config4, zero);
                        break;
                case PARSE_EVENTS__TERM_TYPE_LEGACY_HARDWARE_CONFIG:
                        assert(term->type_val == PARSE_EVENTS__TERM_TYPE_NUM);

@@ -1749,7 +1804,7 @@ static int pmu_config_term(const struct perf_pmu *pmu,
                 */
        }

-       pmu_format_value(format->bits, val, vp, zero);
+       pmu_format_pack(format->bits, val, vp, zero);
        return 0;
 }


--

2.34.1