[PATCH] perf parse: Copy string to perf_evsel_config_term

[Leo Yan]

perf with CoreSight fails to record trace data with command:

  perf record -e cs_etm/@tmc_etr0/u --per-thread ls
  failed to set sink "" on event cs_etm/@tmc_etr0/u with 21 (Is a
  directory)/perf/

This failure is root caused with the commit 1dc925568f01 ("perf
parse: Add a deep delete for parse event terms").

The log shows, cs_etm fails to parse the sink attribution; cs_etm event
relies on the event configuration to pass sink name, but the event
specific configuration data cannot be passed properly with flow:

  get_config_terms()
    ADD_CONFIG_TERM(DRV_CFG, drv_cfg, term->val.str);
      __t->val.drv_cfg = term->val.str;
        `> __t->val.drv_cfg is assigned to term->val.str;

  parse_events_terms__purge()
    parse_events_term__delete()
      zfree(&term->val.str);
        `> term->val.str is freed and assigned to NULL pointer;

  cs_etm_set_sink_attr()
    sink = __t->val.drv_cfg;
      `> sink string has been freed.

To fix this issue, in the function get_config_terms(), this patch
changes from directly assignment pointer value for the strings to
use strdup() for allocation a new duplicate string for the cases:

  perf_evsel_config_term::val.callgraph
  perf_evsel_config_term::val.branch
  perf_evsel_config_term::val.drv_cfg.

Fixes: 1dc925568f01 ("perf parse: Add a deep delete for parse event terms")
Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
---
 tools/perf/util/parse-events.c | 49 ++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index ed7c008b9c8b..5972acdd40d6 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -1220,7 +1220,6 @@ static int get_config_terms(struct list_head *head_config,
 			    struct list_head *head_terms __maybe_unused)
 {
 #define ADD_CONFIG_TERM(__type, __name, __val)			\
-do {								\
 	struct perf_evsel_config_term *__t;			\
 								\
 	__t = zalloc(sizeof(*__t));				\
@@ -1229,9 +1228,19 @@ do {								\
 								\
 	INIT_LIST_HEAD(&__t->list);				\
 	__t->type       = PERF_EVSEL__CONFIG_TERM_ ## __type;	\
-	__t->val.__name = __val;				\
 	__t->weak	= term->weak;				\
-	list_add_tail(&__t->list, head_terms);			\
+	list_add_tail(&__t->list, head_terms)
+
+#define ADD_CONFIG_TERM_VAL(__type, __name, __val)		\
+do {								\
+	ADD_CONFIG_TERM(__type, __name, __val);			\
+	__t->val.__name = __val;				\
+} while (0)
+
+#define ADD_CONFIG_TERM_STR(__type, __name, __val)		\
+do {								\
+	ADD_CONFIG_TERM(__type, __name, __val);			\
+	__t->val.__name = strdup(__val);			\
 } while (0)
 
 	struct parse_events_term *term;
@@ -1239,53 +1248,53 @@ do {								\
 	list_for_each_entry(term, head_config, list) {
 		switch (term->type_term) {
 		case PARSE_EVENTS__TERM_TYPE_SAMPLE_PERIOD:
-			ADD_CONFIG_TERM(PERIOD, period, term->val.num);
+			ADD_CONFIG_TERM_VAL(PERIOD, period, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_SAMPLE_FREQ:
-			ADD_CONFIG_TERM(FREQ, freq, term->val.num);
+			ADD_CONFIG_TERM_VAL(FREQ, freq, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_TIME:
-			ADD_CONFIG_TERM(TIME, time, term->val.num);
+			ADD_CONFIG_TERM_VAL(TIME, time, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_CALLGRAPH:
-			ADD_CONFIG_TERM(CALLGRAPH, callgraph, term->val.str);
+			ADD_CONFIG_TERM_STR(CALLGRAPH, callgraph, term->val.str);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_BRANCH_SAMPLE_TYPE:
-			ADD_CONFIG_TERM(BRANCH, branch, term->val.str);
+			ADD_CONFIG_TERM_STR(BRANCH, branch, term->val.str);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_STACKSIZE:
-			ADD_CONFIG_TERM(STACK_USER, stack_user, term->val.num);
+			ADD_CONFIG_TERM_VAL(STACK_USER, stack_user, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_INHERIT:
-			ADD_CONFIG_TERM(INHERIT, inherit, term->val.num ? 1 : 0);
+			ADD_CONFIG_TERM_VAL(INHERIT, inherit, term->val.num ? 1 : 0);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_NOINHERIT:
-			ADD_CONFIG_TERM(INHERIT, inherit, term->val.num ? 0 : 1);
+			ADD_CONFIG_TERM_VAL(INHERIT, inherit, term->val.num ? 0 : 1);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_MAX_STACK:
-			ADD_CONFIG_TERM(MAX_STACK, max_stack, term->val.num);
+			ADD_CONFIG_TERM_VAL(MAX_STACK, max_stack, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_MAX_EVENTS:
-			ADD_CONFIG_TERM(MAX_EVENTS, max_events, term->val.num);
+			ADD_CONFIG_TERM_VAL(MAX_EVENTS, max_events, term->val.num);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_OVERWRITE:
-			ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 1 : 0);
+			ADD_CONFIG_TERM_VAL(OVERWRITE, overwrite, term->val.num ? 1 : 0);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_NOOVERWRITE:
-			ADD_CONFIG_TERM(OVERWRITE, overwrite, term->val.num ? 0 : 1);
+			ADD_CONFIG_TERM_VAL(OVERWRITE, overwrite, term->val.num ? 0 : 1);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_DRV_CFG:
-			ADD_CONFIG_TERM(DRV_CFG, drv_cfg, term->val.str);
+			ADD_CONFIG_TERM_STR(DRV_CFG, drv_cfg, term->val.str);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_PERCORE:
-			ADD_CONFIG_TERM(PERCORE, percore,
+			ADD_CONFIG_TERM_VAL(PERCORE, percore,
 					term->val.num ? true : false);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_AUX_OUTPUT:
-			ADD_CONFIG_TERM(AUX_OUTPUT, aux_output, term->val.num ? 1 : 0);
+			ADD_CONFIG_TERM_VAL(AUX_OUTPUT, aux_output, term->val.num ? 1 : 0);
 			break;
 		case PARSE_EVENTS__TERM_TYPE_AUX_SAMPLE_SIZE:
-			ADD_CONFIG_TERM(AUX_SAMPLE_SIZE, aux_sample_size, term->val.num);
+			ADD_CONFIG_TERM_VAL(AUX_SAMPLE_SIZE, aux_sample_size, term->val.num);
 			break;
 		default:
 			break;
@@ -1322,7 +1331,7 @@ static int get_config_chgs(struct perf_pmu *pmu, struct list_head *head_config,
 	}
 
 	if (bits)
-		ADD_CONFIG_TERM(CFG_CHG, cfg_chg, bits);
+		ADD_CONFIG_TERM_VAL(CFG_CHG, cfg_chg, bits);
 
 #undef ADD_CONFIG_TERM
 	return 0;
-- 
2.17.1