perf parse-events: Fix propagation of term's no_value when cloning

The no_value field in 'struct parse_events_term' indicates that the val
variable isn't used, the case for an event name.

Cloning wasn't propagating this, making cloned event name terms
appearing to have a constant assinged to them.

Working around the bug would check for a value of 1 assigned to value,
but then this meant a user value of 1 couldn't be differentiated causing
the value to be lost in debug printing and perf list.

The change fixes the cloning and updates the "val.num ==/!= 1" tests to
use no_value instead.

To better check the no_value is set appropriately parameter comments are
added for constant values.

This found that no_value wasn't set correctly in parse_events_multi_pmu_add,
which matters now that no_value is used to indicate an event name.

Fixes: 7a6e91644708d514 ("perf parse-events: Make common term list to strbuf helper")
Fixes: 99e7138eb7897aa0 ("perf tools: Fail on using multiple bits long terms without value")
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230831071421.2201358-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 51b7320..68fe2c4 100644 (file)
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1510,8 +1510,8 @@ int parse_events_multi_pmu_add(struct parse_events_state *parse_state,
 
        if (parse_events_term__num(&term,
                                   PARSE_EVENTS__TERM_TYPE_USER,
-                                  config, 1, false, NULL,
-                                       NULL) < 0) {
+                                  config, /*num=*/1, /*novalue=*/true,
+                                  loc, /*loc_val=*/NULL) < 0) {
                zfree(&config);
                goto out_err;
        }
@@ -2482,7 +2482,7 @@ int parse_events_term__num(struct parse_events_term **term,
                .err_val   = loc_val  ? loc_val->first_column  : 0,
        };
 
-       return new_term(term, &temp, NULL, num);
+       return new_term(term, &temp, /*str=*/NULL, num);
 }
 
 int parse_events_term__str(struct parse_events_term **term,
@@ -2501,7 +2501,7 @@ int parse_events_term__str(struct parse_events_term **term,
                .err_val   = loc_val  ? loc_val->first_column  : 0,
        };
 
-       return new_term(term, &temp, str, 0);
+       return new_term(term, &temp, str, /*num=*/0);
 }
 
 int parse_events_term__term(struct parse_events_term **term,
@@ -2518,26 +2518,21 @@ int parse_events_term__clone(struct parse_events_term **new,
                             struct parse_events_term *term)
 {
        char *str;
-       struct parse_events_term temp = {
-               .type_val  = term->type_val,
-               .type_term = term->type_term,
-               .config    = NULL,
-               .err_term  = term->err_term,
-               .err_val   = term->err_val,
-       };
+       struct parse_events_term temp = *term;
 
+       temp.used = false;
        if (term->config) {
                temp.config = strdup(term->config);
                if (!temp.config)
                        return -ENOMEM;
        }
        if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
-               return new_term(new, &temp, NULL, term->val.num);
+               return new_term(new, &temp, /*str=*/NULL, term->val.num);
 
        str = strdup(term->val.str);
        if (!str)
                return -ENOMEM;
-       return new_term(new, &temp, str, 0);
+       return new_term(new, &temp, str, /*num=*/0);
 }
 
 void parse_events_term__delete(struct parse_events_term *term)
@@ -2611,20 +2606,22 @@ int parse_events_term__to_strbuf(struct list_head *term_list, struct strbuf *sb)
                first = false;
 
                if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM)
-                       if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER && term->val.num == 1)
+                       if (term->no_value) {
+                               assert(term->type_term == PARSE_EVENTS__TERM_TYPE_USER);
                                ret = strbuf_addf(sb, "%s", term->config);
-                       else
+                       } else
                                ret = strbuf_addf(sb, "%s=%#"PRIx64, term->config, term->val.num);
                else if (term->type_val == PARSE_EVENTS__TERM_TYPE_STR) {
                        if (term->config) {
                                ret = strbuf_addf(sb, "%s=", term->config);
                                if (ret < 0)
                                        return ret;
-                       } else if (term->type_term < __PARSE_EVENTS__TERM_TYPE_NR) {
+                       } else if ((unsigned int)term->type_term < __PARSE_EVENTS__TERM_TYPE_NR) {
                                ret = strbuf_addf(sb, "%s=", config_term_name(term->type_term));
                                if (ret < 0)
                                        return ret;
                        }
+                       assert(!term->no_value);
                        ret = strbuf_addf(sb, "%s", term->val.str);
                }
                if (ret < 0)

diff --git a/tools/perf/util/parse-events.y b/tools/perf/util/parse-events.y
index 534daed..4a305df 100644 (file)
--- a/tools/perf/util/parse-events.y
+++ b/tools/perf/util/parse-events.y
@@ -712,7 +712,7 @@ name_or_raw '=' PE_VALUE
 {
        struct parse_events_term *term;
        int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER,
-                                        $1, $3, false, &@1, &@3);
+                                        $1, $3, /*novalue=*/false, &@1, &@3);
 
        if (err) {
                free($1);
@@ -739,7 +739,7 @@ PE_LEGACY_CACHE
 {
        struct parse_events_term *term;
        int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_LEGACY_CACHE,
-                                        $1, 1, true, &@1, NULL);
+                                        $1, /*num=*/1, /*novalue=*/true, &@1, /*loc_val=*/NULL);
 
        if (err) {
                free($1);
@@ -752,7 +752,7 @@ PE_NAME
 {
        struct parse_events_term *term;
        int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_USER,
-                                        $1, 1, true, &@1, NULL);
+                                        $1, /*num=*/1, /*novalue=*/true, &@1, /*loc_val=*/NULL);
 
        if (err) {
                free($1);
@@ -765,7 +765,8 @@ PE_TERM_HW
 {
        struct parse_events_term *term;
        int err = parse_events_term__num(&term, PARSE_EVENTS__TERM_TYPE_HARDWARE,
-                                        $1.str, $1.num & 255, false, &@1, NULL);
+                                        $1.str, $1.num & 255, /*novalue=*/false,
+                                        &@1, /*loc_val=*/NULL);
 
        if (err) {
                free($1.str);

diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 152cda8..d85602a 100644 (file)
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -1396,7 +1396,7 @@ static struct perf_pmu_alias *pmu_find_alias(struct perf_pmu *pmu,
                return NULL;
 
        if (term->type_val == PARSE_EVENTS__TERM_TYPE_NUM) {
-               if (term->val.num != 1)
+               if (!term->no_value)
                        return NULL;
                if (pmu_find_format(&pmu->format, term->config))
                        return NULL;