perf test: Avoid use perf_env

The perf_env global variable holds the host perf_env data but its use
is hit and miss. Switch to using local perf_env variables and ensure
scoped perf_env__init and perf_env__exit. This loses command line
setting of the perf_env, but this doesn't matter for tests. So the
perf_env is fully initialized, clear it with memset in perf_env__init.

Signed-off-by: Ian Rogers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Namhyung Kim <[email protected]>

Author: captain5050

tools/perf/tests/code-reading.c

@@ -651,11 +651,13 @@ static int do_test_code_reading(bool try_kcore)
 	struct dso *dso;
 	const char *events[] = { "cycles", "cycles:u", "cpu-clock", "cpu-clock:u", NULL };
 	int evidx = 0;
+	struct perf_env host_env;
 
 	pid = getpid();
 
 	machine = machine__new_host();
-	machine->env = &perf_env;
+	perf_env__init(&host_env);
+	machine->env = &host_env;
 
 	ret = machine__create_kernel_maps(machine);
 	if (ret < 0) {
@@ -791,6 +793,7 @@ static int do_test_code_reading(bool try_kcore)
 	perf_cpu_map__put(cpus);
 	perf_thread_map__put(threads);
 	machine__delete(machine);
+	perf_env__exit(&host_env);
 
 	return err;
 }

tools/perf/tests/dlfilter-test.c

@@ -319,11 +319,12 @@ static int run_perf_script(struct test_data *td)
 
 static int test__dlfilter_test(struct test_data *td)
 {
+	struct perf_env host_env;
 	u64 sample_type = TEST_SAMPLE_TYPE;
 	pid_t pid = 12345;
 	pid_t tid = 12346;
 	u64 id = 99;
-	int err;
+	int err = TEST_OK;
 
 	if (get_dlfilters_path(td->name, td->dlfilters, PATH_MAX))
 		return test_result("dlfilters not found", TEST_SKIP);
@@ -353,37 +354,42 @@ static int test__dlfilter_test(struct test_data *td)
 
 	pr_debug("Creating new host machine structure\n");
 	td->machine = machine__new_host();
-	td->machine->env = &perf_env;
+	perf_env__init(&host_env);
+	td->machine->env = &host_env;
 
 	td->fd = creat(td->perf_data_file_name, 0644);
 	if (td->fd < 0)
 		return test_result("Failed to create test perf.data file", TEST_FAIL);
 
 	err = perf_header__write_pipe(td->fd);
-	if (err < 0)
-		return test_result("perf_header__write_pipe() failed", TEST_FAIL);
-
+	if (err < 0) {
+		err = test_result("perf_header__write_pipe() failed", TEST_FAIL);
+		goto out;
+	}
 	err = write_attr(td, sample_type, &id);
-	if (err)
-		return test_result("perf_event__synthesize_attr() failed", TEST_FAIL);
-
-	if (write_comm(td->fd, pid, tid, "test-prog"))
-		return TEST_FAIL;
-
-	if (write_mmap(td->fd, pid, tid, MAP_START, 0x10000, 0, td->prog_file_name))
-		return TEST_FAIL;
-
-	if (write_sample(td, sample_type, id, pid, tid) != TEST_OK)
-		return TEST_FAIL;
-
+	if (err) {
+		err = test_result("perf_event__synthesize_attr() failed", TEST_FAIL);
+		goto out;
+	}
+	if (write_comm(td->fd, pid, tid, "test-prog")) {
+		err = TEST_FAIL;
+		goto out;
+	}
+	if (write_mmap(td->fd, pid, tid, MAP_START, 0x10000, 0, td->prog_file_name)) {
+		err = TEST_FAIL;
+		goto out;
+	}
+	if (write_sample(td, sample_type, id, pid, tid) != TEST_OK) {
+		err = TEST_FAIL;
+		goto out;
+	}
 	if (verbose > 1)
 		system_cmd("%s script -i %s -D", td->perf, td->perf_data_file_name);
 
-	err = run_perf_script(td);
-	if (err)
-		return TEST_FAIL;
-
-	return TEST_OK;
+	err = run_perf_script(td) ? TEST_FAIL : TEST_OK;
+out:
+	perf_env__exit(&host_env);
+	return err;
 }
 
 static void unlink_path(const char *path)

tools/perf/util/env.c

@@ -271,6 +271,7 @@ void perf_env__exit(struct perf_env *env)
 
 void perf_env__init(struct perf_env *env)
 {
+	memset(env, 0, sizeof(*env));
 #ifdef HAVE_LIBBPF_SUPPORT
 	env->bpf_progs.infos = RB_ROOT;
 	env->bpf_progs.btfs = RB_ROOT;