perf pmu: When using default config, record which bits of config were changed by...

Default config for a PMU is defined before selected events are parsed.
That allows the user-entered config to override the default config.

However that does not allow for changing the default config based on
other options.

For example, if the user chooses AUX area sampling mode, in the case of
Intel PT, the psb_period needs to be small for sampling, so there is a
need to set the default psb_period to 0 (2 KiB) in that case. However
that should not override a value set by the user. To allow for that,
when using default config, record which bits of config were changed by
the user.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20191115124225.5247-13-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index ad7665a546cf15bec2c1f5fb879209e0bd2c3cf8..f4dea055b0808941229374cf6a93d7992888b406 100644 (file)
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -849,6 +849,8 @@ static void apply_config_terms(struct evsel *evsel,
                case PERF_EVSEL__CONFIG_TERM_AUX_SAMPLE_SIZE:
                        /* Already applied by auxtrace */
                        break;
+               case PERF_EVSEL__CONFIG_TERM_CFG_CHG:
+                       break;
                default:
                        break;
                }

diff --git a/tools/perf/util/evsel_config.h b/tools/perf/util/evsel_config.h
index 6e654ede8fbe26053d135cf9f0b67b8afbe00622..1f8d2fe0b66eda531aaf33b02dbe6888076c943c 100644 (file)
--- a/tools/perf/util/evsel_config.h
+++ b/tools/perf/util/evsel_config.h
@@ -26,6 +26,7 @@ enum evsel_term_type {
        PERF_EVSEL__CONFIG_TERM_PERCORE,
        PERF_EVSEL__CONFIG_TERM_AUX_OUTPUT,
        PERF_EVSEL__CONFIG_TERM_AUX_SAMPLE_SIZE,
+       PERF_EVSEL__CONFIG_TERM_CFG_CHG,
 };
 
 struct perf_evsel_config_term {
@@ -46,6 +47,7 @@ struct perf_evsel_config_term {
                bool          percore;
                bool          aux_output;
                u32           aux_sample_size;
+               u64           cfg_chg;
        } val;
        bool weak;
 };

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index fc5e27bc8315b9b5da829687bbb7dc7301b93114..6c313c4087edcb99c94d24ceb91bff6055ad015e 100644 (file)
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1290,7 +1290,40 @@ do {                                                             \
                        break;
                }
        }
-#undef ADD_EVSEL_CONFIG
+       return 0;
+}
+
+/*
+ * Add PERF_EVSEL__CONFIG_TERM_CFG_CHG where cfg_chg will have a bit set for
+ * each bit of attr->config that the user has changed.
+ */
+static int get_config_chgs(struct perf_pmu *pmu, struct list_head *head_config,
+                          struct list_head *head_terms)
+{
+       struct parse_events_term *term;
+       u64 bits = 0;
+       int type;
+
+       list_for_each_entry(term, head_config, list) {
+               switch (term->type_term) {
+               case PARSE_EVENTS__TERM_TYPE_USER:
+                       type = perf_pmu__format_type(&pmu->format, term->config);
+                       if (type != PERF_PMU_FORMAT_VALUE_CONFIG)
+                               continue;
+                       bits |= perf_pmu__format_bits(&pmu->format, term->config);
+                       break;
+               case PARSE_EVENTS__TERM_TYPE_CONFIG:
+                       bits = ~(u64)0;
+                       break;
+               default:
+                       break;
+               }
+       }
+
+       if (bits)
+               ADD_CONFIG_TERM(CFG_CHG, cfg_chg, bits);
+
+#undef ADD_CONFIG_TERM
        return 0;
 }
 
@@ -1419,6 +1452,13 @@ int parse_events_add_pmu(struct parse_events_state *parse_state,
        if (get_config_terms(head_config, &config_terms))
                return -ENOMEM;
 
+       /*
+        * When using default config, record which bits of attr->config were
+        * changed by the user.
+        */
+       if (pmu->default_config && get_config_chgs(pmu, head_config, &config_terms))
+               return -ENOMEM;
+
        if (perf_pmu__config(pmu, &attr, head_config, parse_state->error)) {
                struct perf_evsel_config_term *pos, *tmp;
 

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index db1e57113f4ba4320f8c4a03cc4644fc3aa3e169..e8d34898802607e26ccd930a7fb8bea5af65587a 100644 (file)
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -931,6 +931,16 @@ __u64 perf_pmu__format_bits(struct list_head *formats, const char *name)
        return bits;
 }
 
+int perf_pmu__format_type(struct list_head *formats, const char *name)
+{
+       struct perf_pmu_format *format = pmu_find_format(formats, name);
+
+       if (!format)
+               return -1;
+
+       return format->value;
+}
+
 /*
  * Sets value based on the format definition (format parameter)
  * and unformated value (value parameter).

diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index 2eb7a70013077cb768164dd015a2975dfbc50ee7..6737e3d5d568c2f897ff18935f18963ece3fd068 100644 (file)
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -72,6 +72,7 @@ int perf_pmu__config_terms(struct list_head *formats,
                           struct list_head *head_terms,
                           bool zero, struct parse_events_error *error);
 __u64 perf_pmu__format_bits(struct list_head *formats, const char *name);
+int perf_pmu__format_type(struct list_head *formats, const char *name);
 int perf_pmu__check_alias(struct perf_pmu *pmu, struct list_head *head_terms,
                          struct perf_pmu_info *info);
 struct list_head *perf_pmu__alias(struct perf_pmu *pmu,