perf parse-events: Support event alias in form foo-bar-baz

Event aliasing for events whose name in the form foo-bar-baz is not
supported, while foo-bar, foo_bar_baz, and other combinations are, i.e.
two hyphens are not supported.

The HiSilicon D06 platform has events in such form:

$ ./perf list sdir-home-migrate

List of pre-defined events (to be used in -e):

uncore hha:
sdir-home-migrate
[Unit: hisi_sccl,hha]

$ sudo ./perf stat -e sdir-home-migrate
event syntax error: 'sdir-home-migrate'
\___ parser error
Run 'perf list' for a list of valid events

Usage: perf stat [<options>] [<command>]

-e, --event <event>event selector. use 'perf list' to list available events

To support, add an extra PMU event symbol type for "baz", and add a new
rule in the bison file.

Signed-off-by: John Garry <[e-mail]>
Acked-by: Ian Rogers <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Kajol Jain <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Qi Liu <[e-mail]>
Cc: Shaokun Zhang <[e-mail]>
Cc: [e-mail]
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/parse-events.c

···
 	pmu = NULL;
 	while ((pmu = perf_pmu__scan(pmu)) != NULL) {
 		list_for_each_entry(alias, &pmu->aliases, list) {
-			if (strchr(alias->name, '-'))
+			char *tmp = strchr(alias->name, '-');
+
+			if (tmp) {
+				char *tmp2 = NULL;
+
+				tmp2 = strchr(tmp + 1, '-');
 				len++;
+				if (tmp2)
+					len++;
+			}
+
 			len++;
 		}
 	}
···
 		list_for_each_entry(alias, &pmu->aliases, list) {
 			struct perf_pmu_event_symbol *p = perf_pmu_events_list + len;
 			char *tmp = strchr(alias->name, '-');
+			char *tmp2 = NULL;
 
-			if (tmp != NULL) {
+			if (tmp)
+				tmp2 = strchr(tmp + 1, '-');
+			if (tmp2) {
+				SET_SYMBOL(strndup(alias->name, tmp - alias->name),
+						PMU_EVENT_SYMBOL_PREFIX);
+				p++;
+				tmp++;
+				SET_SYMBOL(strndup(tmp, tmp2 - tmp), PMU_EVENT_SYMBOL_SUFFIX);
+				p++;
+				SET_SYMBOL(strdup(++tmp2), PMU_EVENT_SYMBOL_SUFFIX2);
+				len += 3;
+			} else if (tmp) {
 				SET_SYMBOL(strndup(alias->name, tmp - alias->name),
 						PMU_EVENT_SYMBOL_PREFIX);
 				p++;

tools/perf/util/parse-events.h

···
 	PMU_EVENT_SYMBOL,		/* normal style PMU event */
 	PMU_EVENT_SYMBOL_PREFIX,	/* prefix of pre-suf style event */
 	PMU_EVENT_SYMBOL_SUFFIX,	/* suffix of pre-suf style event */
+	PMU_EVENT_SYMBOL_SUFFIX2,	/* suffix of pre-suf2 style event */
 };
 
 struct perf_pmu_event_symbol {

tools/perf/util/parse-events.l

···
 			return PE_PMU_EVENT_PRE;
 		case PMU_EVENT_SYMBOL_SUFFIX:
 			return PE_PMU_EVENT_SUF;
+		case PMU_EVENT_SYMBOL_SUFFIX2:
+			return PE_PMU_EVENT_SUF2;
 		case PMU_EVENT_SYMBOL:
 			return parse_state->fake_pmu
 				? PE_PMU_EVENT_FAKE : PE_KERNEL_PMU_EVENT;

tools/perf/util/parse-events.y

···
 %token PE_NAME_CACHE_TYPE PE_NAME_CACHE_OP_RESULT
 %token PE_PREFIX_MEM PE_PREFIX_RAW PE_PREFIX_GROUP
 %token PE_ERROR
-%token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
+%token PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_PMU_EVENT_SUF2 PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
 %token PE_ARRAY_ALL PE_ARRAY_RANGE
 %token PE_DRV_CFG_TERM
 %type <num> PE_VALUE
···
 %type <str> PE_MODIFIER_EVENT
 %type <str> PE_MODIFIER_BP
 %type <str> PE_EVENT_NAME
-%type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
+%type <str> PE_PMU_EVENT_PRE PE_PMU_EVENT_SUF PE_PMU_EVENT_SUF2 PE_KERNEL_PMU_EVENT PE_PMU_EVENT_FAKE
 %type <str> PE_DRV_CFG_TERM
 %type <str> event_pmu_name
 %destructor { free ($$); } <str>
···
 	err = parse_events_multi_pmu_add(_parse_state, $1, $2, &list);
 	free($1);
 	if (err < 0)
+		YYABORT;
+	$$ = list;
+}
+|
+PE_PMU_EVENT_PRE '-' PE_PMU_EVENT_SUF '-' PE_PMU_EVENT_SUF2 sep_dc
+{
+	struct list_head *list;
+	char pmu_name[128];
+	snprintf(pmu_name, sizeof(pmu_name), "%s-%s-%s", $1, $3, $5);
+	free($1);
+	free($3);
+	free($5);
+	if (parse_events_multi_pmu_add(_parse_state, pmu_name, NULL, &list) < 0)
 		YYABORT;
 	$$ = list;
 }