perf tools: Support parsing parameterized events

Enable event specification like:

	pmu/event_name,param1=0x1,param2=0x4/

Assuming that

	/sys/bus/event_source/devices/pmu/events/event_name

Contains something like

	param2=?,bar=1,param1=?

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Haren Myneni <hbabu@us.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1420679633-28856-2-git-send-email-sukadev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 64 insertions, 11 deletions

diff --git a/tools/perf/util/parse-events.h b/tools/perf/util/parse-events.h
index db2cf78ff0f3..ca226cef8460 100644
--- a/tools/perf/util/parse-events.h
+++ b/tools/perf/util/parse-events.h
@@ -71,6 +71,7 @@ struct parse_events_term {
         int type_val;
         int type_term;
         struct list_head list;
+        bool used;
 };
 
 struct parse_events_evlist {
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 5c9c4947cfb4..bfbecf7abd38 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -551,31 +551,68 @@ static void pmu_format_value(unsigned long *format, __u64 value, __u64 *v,
 }
 
 /*
+ * Term is a string term, and might be a param-term. Try to look up it's value
+ * in the remaining terms.
+ * - We have a term like "base-or-format-term=param-term",
+ * - We need to find the value supplied for "param-term" (with param-term named
+ *   in a config string) later on in the term list.
+ */
+static int pmu_resolve_param_term(struct parse_events_term *term,
+                                  struct list_head *head_terms,
+                                  __u64 *value)
+{
+        struct parse_events_term *t;
+
+        list_for_each_entry(t, head_terms, list) {
+                if (t->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
+                        if (!strcmp(t->config, term->config)) {
+                                t->used = true;
+                                *value = t->val.num;
+                                return 0;
+                        }
+                }
+        }
+
+        if (verbose)
+                printf("Required parameter '%s' not specified\n", term->config);
+
+        return -1;
+}
+
+/*
  * Setup one of config[12] attr members based on the
  * user input data - term parameter.
  */
 static int pmu_config_term(struct list_head *formats,
                            struct perf_event_attr *attr,
                            struct parse_events_term *term,
+                           struct list_head *head_terms,
                            bool zero)
 {
         struct perf_pmu_format *format;
         __u64 *vp;
+        __u64 val;
+
+        /*
+         * If this is a parameter we've already used for parameterized-eval,
+         * skip it in normal eval.
+         */
+        if (term->used)
+                return 0;
 
         /*
-         * Support only for hardcoded and numnerial terms.
          * Hardcoded terms should be already in, so nothing
          * to be done for them.
          */
         if (parse_events__is_hardcoded_term(term))
                 return 0;
 
-        if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM)
-                return -EINVAL;
-
         format = pmu_find_format(formats, term->config);
-        if (!format)
+        if (!format) {
+                if (verbose)
+                        printf("Invalid event/parameter '%s'\n", term->config);
                 return -EINVAL;
+        }
 
         switch (format->value) {
         case PERF_PMU_FORMAT_VALUE_CONFIG:
@@ -592,11 +629,25 @@ static int pmu_config_term(struct list_head *formats,
         }
 
         /*
-         * XXX If we ever decide to go with string values for
-         * non-hardcoded terms, here's the place to translate
-         * them into value.
+         * Either directly use a numeric term, or try to translate string terms
+         * using event parameters.
          */
-        pmu_format_value(format->bits, term->val.num, vp, zero);
+        if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
+                val = term->val.num;
+        else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
+                if (strcmp(term->val.str, "?")) {
+                        if (verbose)
+                                pr_info("Invalid sysfs entry %s=%s\n",
+                                                term->config, term->val.str);
+                        return -EINVAL;
+                }
+
+                if (pmu_resolve_param_term(term, head_terms, &val))
+                        return -EINVAL;
+        } else
+                return -EINVAL;
+
+        pmu_format_value(format->bits, val, vp, zero);
         return 0;
 }
 
@@ -607,9 +658,10 @@ int perf_pmu__config_terms(struct list_head *formats,
 {
         struct parse_events_term *term;
 
-        list_for_each_entry(term, head_terms, list)
-                if (pmu_config_term(formats, attr, term, zero))
+        list_for_each_entry(term, head_terms, list) {
+                if (pmu_config_term(formats, attr, term, head_terms, zero))
                         return -EINVAL;
+        }
 
         return 0;
 }