perf pmu: Change aliases from list to hashmap

Finding an alias for things like perf_pmu__have_event() would need to
search the aliases list, whilst this happens relatively infrequently it
can be a significant overhead in testing.

Switch to using a hashmap. Move common initialization code to
perf_pmu__init(). Refactor the test 'struct perf_pmu_test_pmu' to not
have perf pmu within it to better support the perf_pmu__init() function.

Before:
```
$ time perf test "Parsing of PMU event table metrics"
 10.3: Parsing of PMU event table metrics                            : Ok
 10.4: Parsing of PMU event table metrics with fake PMUs             : Ok

real    0m13.287s
user    0m13.026s
sys     0m0.532s
```

After:
```
$ time perf test "Parsing of PMU event table metrics"
 10.3: Parsing of PMU event table metrics                            : Ok
 10.4: Parsing of PMU event table metrics with fake PMUs             : Ok

real    0m13.011s
user    0m12.885s
sys     0m0.485s
```

Committer testing:

  root@number:~# grep -m1 'model name' /proc/cpuinfo
  model name	: AMD Ryzen 9 9950X3D 16-Core Processor
  root@number:~#

Before:

  root@number:~# time perf test "Parsing of PMU event table metrics"
   10.3: Parsing of PMU event table metrics                            : Ok
   10.4: Parsing of PMU event table metrics with fake PMUs             : Ok

  real	0m9.296s
  user	0m9.361s
  sys	0m0.063s
  root@number:~#

After:

  root@number:~# time perf test "Parsing of PMU event table metrics"
   10.3: Parsing of PMU event table metrics                            : Ok
   10.4: Parsing of PMU event table metrics with fake PMUs             : Ok

  real	0m9.286s
  user	0m9.354s
  sys	0m0.062s
  root@number:~#

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Namhyung Kim <namhyung@kernel.org>
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@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20250512194622.33258-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: captain5050

tools/perf/tests/pmu-events.c

@@ -38,7 +38,9 @@ struct perf_pmu_test_event {
 };
 
 struct perf_pmu_test_pmu {
-	struct perf_pmu pmu;
+	const char *pmu_name;
+	bool pmu_is_uncore;
+	const char *pmu_id;
 	struct perf_pmu_test_event const *aliases[10];
 };
 
@@ -553,11 +555,10 @@ static int __test_core_pmu_event_aliases(const char *pmu_name, int *count)
 	if (!pmu)
 		return -1;
 
-	INIT_LIST_HEAD(&pmu->format);
-	INIT_LIST_HEAD(&pmu->aliases);
-	INIT_LIST_HEAD(&pmu->caps);
-	INIT_LIST_HEAD(&pmu->list);
-	pmu->name = strdup(pmu_name);
+	if (perf_pmu__init(pmu, PERF_PMU_TYPE_FAKE, pmu_name) != 0) {
+		perf_pmu__delete(pmu);
+		return -1;
+	}
 	pmu->is_core = true;
 
 	pmu->events_table = table;
@@ -594,14 +595,30 @@ static int __test_uncore_pmu_event_aliases(struct perf_pmu_test_pmu *test_pmu)
 {
 	int alias_count = 0, to_match_count = 0, matched_count = 0;
 	struct perf_pmu_test_event const **table;
-	struct perf_pmu *pmu = &test_pmu->pmu;
-	const char *pmu_name = pmu->name;
+	struct perf_pmu *pmu;
 	const struct pmu_events_table *events_table;
 	int res = 0;
 
 	events_table = find_core_events_table("testarch", "testcpu");
 	if (!events_table)
 		return -1;
+
+	pmu = zalloc(sizeof(*pmu));
+	if (!pmu)
+		return -1;
+
+	if (perf_pmu__init(pmu, PERF_PMU_TYPE_FAKE, test_pmu->pmu_name) != 0) {
+		perf_pmu__delete(pmu);
+		return -1;
+	}
+	pmu->is_uncore = test_pmu->pmu_is_uncore;
+	if (test_pmu->pmu_id) {
+		pmu->id = strdup(test_pmu->pmu_id);
+		if (!pmu->id) {
+			perf_pmu__delete(pmu);
+			return -1;
+		}
+	}
 	pmu->events_table = events_table;
 	pmu_add_cpu_aliases_table(pmu, events_table);
 	pmu->cpu_aliases_added = true;
@@ -617,7 +634,8 @@ static int __test_uncore_pmu_event_aliases(struct perf_pmu_test_pmu *test_pmu)
 
 	if (alias_count != to_match_count) {
 		pr_debug("testing aliases uncore PMU %s: mismatch expected aliases (%d) vs found (%d)\n",
-			 pmu_name, to_match_count, alias_count);
+			 pmu->name, to_match_count, alias_count);
+		perf_pmu__delete(pmu);
 		return -1;
 	}
 
@@ -630,9 +648,10 @@ static int __test_uncore_pmu_event_aliases(struct perf_pmu_test_pmu *test_pmu)
 			.count = &matched_count,
 		};
 
-		if (strcmp(pmu_name, test_event.matching_pmu)) {
+		if (strcmp(pmu->name, test_event.matching_pmu)) {
 			pr_debug("testing aliases uncore PMU %s: mismatched matching_pmu, %s vs %s\n",
-					pmu_name, test_event.matching_pmu, pmu_name);
+					pmu->name, test_event.matching_pmu, pmu->name);
+			perf_pmu__delete(pmu);
 			return -1;
 		}
 
@@ -641,123 +660,103 @@ static int __test_uncore_pmu_event_aliases(struct perf_pmu_test_pmu *test_pmu)
 		if (err) {
 			res = err;
 			pr_debug("testing aliases uncore PMU %s: could not match alias %s\n",
-				 pmu_name, event->name);
+				 pmu->name, event->name);
+			perf_pmu__delete(pmu);
 			return -1;
 		}
 	}
 
 	if (alias_count != matched_count) {
 		pr_debug("testing aliases uncore PMU %s: mismatch found aliases (%d) vs matched (%d)\n",
-			 pmu_name, matched_count, alias_count);
+			 pmu->name, matched_count, alias_count);
 		res = -1;
 	}
+	perf_pmu__delete(pmu);
 	return res;
 }
 
 static struct perf_pmu_test_pmu test_pmus[] = {
 	{
-		.pmu = {
-			.name = "hisi_sccl1_ddrc2",
-			.is_uncore = 1,
-		},
+		.pmu_name = "hisi_sccl1_ddrc2",
+		.pmu_is_uncore = 1,
 		.aliases = {
 			&uncore_hisi_ddrc_flux_wcmd,
 		},
 	},
 	{
-		.pmu = {
-			.name = "uncore_cbox_0",
-			.is_uncore = 1,
-		},
+		.pmu_name = "uncore_cbox_0",
+		.pmu_is_uncore = 1,
 		.aliases = {
 			&unc_cbo_xsnp_response_miss_eviction,
 			&uncore_hyphen,
 			&uncore_two_hyph,
 		},
 	},
 	{
-		.pmu = {
-			.name = "hisi_sccl3_l3c7",
-			.is_uncore = 1,
-		},
+		.pmu_name = "hisi_sccl3_l3c7",
+		.pmu_is_uncore = 1,
 		.aliases = {
 			&uncore_hisi_l3c_rd_hit_cpipe,
 		},
 	},
 	{
-		.pmu = {
-			.name = "uncore_imc_free_running_0",
-			.is_uncore = 1,
-		},
+		.pmu_name = "uncore_imc_free_running_0",
+		.pmu_is_uncore = 1,
 		.aliases = {
 			&uncore_imc_free_running_cache_miss,
 		},
 	},
 	{
-		.pmu = {
-			.name = "uncore_imc_0",
-			.is_uncore = 1,
-		},
+		.pmu_name = "uncore_imc_0",
+		.pmu_is_uncore = 1,
 		.aliases = {
 			&uncore_imc_cache_hits,
 		},
 	},
 	{
-		.pmu = {
-			.name = "uncore_sys_ddr_pmu0",
-			.is_uncore = 1,
-			.id = "v8",
-		},
+		.pmu_name = "uncore_sys_ddr_pmu0",
+		.pmu_is_uncore = 1,
+		.pmu_id = "v8",
 		.aliases = {
 			&sys_ddr_pmu_write_cycles,
 		},
 	},
 	{
-		.pmu = {
-			.name = "uncore_sys_ccn_pmu4",
-			.is_uncore = 1,
-			.id = "0x01",
-		},
+		.pmu_name = "uncore_sys_ccn_pmu4",
+		.pmu_is_uncore = 1,
+		.pmu_id = "0x01",
 		.aliases = {
 			&sys_ccn_pmu_read_cycles,
 		},
 	},
 	{
-		.pmu = {
-			.name = (char *)"uncore_sys_cmn_pmu0",
-			.is_uncore = 1,
-			.id = (char *)"43401",
-		},
+		.pmu_name = "uncore_sys_cmn_pmu0",
+		.pmu_is_uncore = 1,
+		.pmu_id = "43401",
 		.aliases = {
 			&sys_cmn_pmu_hnf_cache_miss,
 		},
 	},
 	{
-		.pmu = {
-			.name = (char *)"uncore_sys_cmn_pmu0",
-			.is_uncore = 1,
-			.id = (char *)"43602",
-		},
+		.pmu_name = "uncore_sys_cmn_pmu0",
+		.pmu_is_uncore = 1,
+		.pmu_id = "43602",
 		.aliases = {
 			&sys_cmn_pmu_hnf_cache_miss,
 		},
 	},
 	{
-		.pmu = {
-			.name = (char *)"uncore_sys_cmn_pmu0",
-			.is_uncore = 1,
-			.id = (char *)"43c03",
-		},
+		.pmu_name = "uncore_sys_cmn_pmu0",
+		.pmu_is_uncore = 1,
+		.pmu_id = "43c03",
 		.aliases = {
 			&sys_cmn_pmu_hnf_cache_miss,
 		},
 	},
 	{
-		.pmu = {
-			.name = (char *)"uncore_sys_cmn_pmu0",
-			.is_uncore = 1,
-			.id = (char *)"43a01",
-		},
+		.pmu_name = "uncore_sys_cmn_pmu0",
+		.pmu_is_uncore = 1,
+		.pmu_id = "43a01",
 		.aliases = {
 			&sys_cmn_pmu_hnf_cache_miss,
 		},
@@ -796,10 +795,6 @@ static int test__aliases(struct test_suite *test __maybe_unused,
 	for (i = 0; i < ARRAY_SIZE(test_pmus); i++) {
 		int res;
 
-		INIT_LIST_HEAD(&test_pmus[i].pmu.format);
-		INIT_LIST_HEAD(&test_pmus[i].pmu.aliases);
-		INIT_LIST_HEAD(&test_pmus[i].pmu.caps);
-
 		res = __test_uncore_pmu_event_aliases(&test_pmus[i]);
 		if (res)
 			return res;

tools/perf/util/hwmon_pmu.c

@@ -346,42 +346,43 @@ struct perf_pmu *hwmon_pmu__new(struct list_head *pmus, int hwmon_dir, const cha
 {
 	char buf[32];
 	struct hwmon_pmu *hwm;
+	__u32 type = PERF_PMU_TYPE_HWMON_START + strtoul(sysfs_name + 5, NULL, 10);
+
+	if (type > PERF_PMU_TYPE_HWMON_END) {
+		pr_err("Unable to encode hwmon type from %s in valid PMU type\n", sysfs_name);
+		return NULL;
+	}
+
+	snprintf(buf, sizeof(buf), "hwmon_%s", name);
+	fix_name(buf + 6);
 
 	hwm = zalloc(sizeof(*hwm));
 	if (!hwm)
 		return NULL;
 
-	hwm->hwmon_dir_fd = hwmon_dir;
-	hwm->pmu.type = PERF_PMU_TYPE_HWMON_START + strtoul(sysfs_name + 5, NULL, 10);
-	if (hwm->pmu.type > PERF_PMU_TYPE_HWMON_END) {
-		pr_err("Unable to encode hwmon type from %s in valid PMU type\n", sysfs_name);
-		goto err_out;
+	if (perf_pmu__init(&hwm->pmu, type, buf) != 0) {
+		perf_pmu__delete(&hwm->pmu);
+		return NULL;
 	}
-	snprintf(buf, sizeof(buf), "hwmon_%s", name);
-	fix_name(buf + 6);
-	hwm->pmu.name = strdup(buf);
-	if (!hwm->pmu.name)
-		goto err_out;
+
+	hwm->hwmon_dir_fd = hwmon_dir;
 	hwm->pmu.alias_name = strdup(sysfs_name);
-	if (!hwm->pmu.alias_name)
-		goto err_out;
+	if (!hwm->pmu.alias_name) {
+		perf_pmu__delete(&hwm->pmu);
+		return NULL;
+	}
 	hwm->pmu.cpus = perf_cpu_map__new("0");
-	if (!hwm->pmu.cpus)
-		goto err_out;
+	if (!hwm->pmu.cpus) {
+		perf_pmu__delete(&hwm->pmu);
+		return NULL;
+	}
 	INIT_LIST_HEAD(&hwm->pmu.format);
-	INIT_LIST_HEAD(&hwm->pmu.aliases);
 	INIT_LIST_HEAD(&hwm->pmu.caps);
 	hashmap__init(&hwm->events, hwmon_pmu__event_hashmap_hash,
 		      hwmon_pmu__event_hashmap_equal, /*ctx=*/NULL);
 
 	list_add_tail(&hwm->pmu.list, pmus);
 	return &hwm->pmu;
-err_out:
-	free((char *)hwm->pmu.name);
-	free(hwm->pmu.alias_name);
-	free(hwm);
-	close(hwmon_dir);
-	return NULL;
 }
 
 void hwmon_pmu__exit(struct perf_pmu *pmu)