perf lock: Provide a host_env for session new

When "perf lock con" is run in a live mode, with no data file, a host
environment must be provided. Testing missed this as a failing assert
was creating the 1 line of expected stderr output.

  $ sudo perf lock con -ab true
  perf: util/session.c:195: __perf_session__new: Assertion `host_env != NULL' failed.
  Aborted

Fixes: 525a599badeeafba ("perf env: Remove global perf_env")
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index fd49703..0786344 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -2009,6 +2009,7 @@ static int __cmd_contention(int argc, const char **argv)
 		.owner = show_lock_owner,
 		.cgroups = RB_ROOT,
 	};
+	struct perf_env host_env;
 
 	lockhash_table = calloc(LOCKHASH_SIZE, sizeof(*lockhash_table));
 	if (!lockhash_table)
@@ -2024,7 +2025,10 @@ static int __cmd_contention(int argc, const char **argv)
 	eops.mmap		 = perf_event__process_mmap;
 	eops.tracing_data	 = perf_event__process_tracing_data;
 
-	session = perf_session__new(use_bpf ? NULL : &data, &eops);
+	perf_env__init(&host_env);
+	session = __perf_session__new(use_bpf ? NULL : &data, &eops,
+				/*trace_event_repipe=*/false, &host_env);
+
 	if (IS_ERR(session)) {
 		pr_err("Initializing perf session failed\n");
 		err = PTR_ERR(session);
@@ -2142,6 +2146,7 @@ static int __cmd_contention(int argc, const char **argv)
 	evlist__delete(con.evlist);
 	lock_contention_finish(&con);
 	perf_session__delete(session);
+	perf_env__exit(&host_env);
 	zfree(&lockhash_table);
 	return err;
 }