Skip to content

CDRIVER-748 fix mock server for TSAN #620

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
kevinAlbs merged 2 commits into from
May 29, 2020
Merged

CDRIVER-748 fix mock server for TSAN #620

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
ebdd327
CDRIVER-748 fix mock server for TSAN
kevinAlbs May 25, 2020
0f1842e
fix warning
kevinAlbs May 25, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
42 changes: 29 additions & 13 deletions src/libmongoc/tests/mock_server/mock-server.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -72,8 +72,13 @@ struct _autoresponder_handle_t {
int id;
};

typedef enum {
REPLY, HANGUP, RESET
} reply_type_t;


typedef struct {
reply_type_t type;
mongoc_reply_flags_t flags;
bson_t *docs;
int n_docs;
Expand Down Expand Up @@ -1218,12 +1223,14 @@ mock_server_receives_kill_cursors (mock_server_t *server, int64_t cursor_id)
void
mock_server_hangs_up (request_t *request)
{
reply_t *reply;
test_suite_mock_server_log ("%5.2f %hu <- %hu \thang up!",
mock_server_get_uptime_sec (request->server),
request->client_port,
request_get_server_port (request));

mongoc_stream_close (request->client);
reply = bson_malloc0 (sizeof (reply_t));
reply->type = HANGUP;
q_put (request->replies, reply);
Copy link
Collaborator Author

@kevinAlbs kevinAlbs May 25, 2020 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The behavior of mock_server_hangs_up was to close the server side stream from the main thread. TSan flags a data race because in the process of closing, it overwrites the stream's file descriptor with an invalid one, causing a write/read race.

The mock server maintains a worker thread for each server-side connection. And each worker thread maintains a thread-safe queue for sending replies back. So instead of closing the stream directly, this pushes a special reply onto the queue to signal the worker thread to close the stream.

}


Expand All @@ -1245,20 +1252,15 @@ mock_server_hangs_up (request_t *request)
void
mock_server_resets (request_t *request)
{
struct linger no_linger;
no_linger.l_onoff = 1;
no_linger.l_linger = 0;

reply_t *reply;
test_suite_mock_server_log ("%5.2f %hu <- %hu \treset!",
mock_server_get_uptime_sec (request->server),
request->client_port,
request_get_server_port (request));

/* send RST packet to client */
mongoc_stream_setsockopt (
request->client, SOL_SOCKET, SO_LINGER, &no_linger, sizeof no_linger);

mongoc_stream_close (request->client);
reply = bson_malloc0 (sizeof (reply_t));
reply->type = RESET;
q_put (request->replies, reply);
}


Expand Down Expand Up @@ -1331,7 +1333,6 @@ mock_server_replies_simple (request_t *request, const char *docs_json)
mock_server_replies (request, MONGOC_REPLY_NONE, 0, 0, 1, docs_json);
}


/*--------------------------------------------------------------------------
*
* mock_server_replies_ok_and_destroys --
Expand Down Expand Up @@ -1801,6 +1802,7 @@ mock_server_reply_multi (request_t *request,

reply = bson_malloc0 (sizeof (reply_t));

reply->type = REPLY;
reply->flags = flags;
reply->n_docs = n_docs;
reply->docs = bson_malloc0 (n_docs * sizeof (bson_t));
Expand Down Expand Up @@ -1837,12 +1839,26 @@ _mock_server_reply_with_stream (mock_server_t *server,
uint8_t *ptr;
size_t len;
bool is_op_msg;

mongoc_reply_flags_t flags = reply->flags;
const bson_t *docs = reply->docs;
int n_docs = reply->n_docs;
int64_t cursor_id = reply->cursor_id;

if (reply->type == HANGUP) {
mongoc_stream_close (client);
return;
} else if (reply->type == RESET) {
struct linger no_linger;
no_linger.l_onoff = 1;
no_linger.l_linger = 0;

/* send RST packet to client */
mongoc_stream_setsockopt (client, SOL_SOCKET, SO_LINGER, &no_linger, sizeof no_linger);

mongoc_stream_close (client);
return;
}

docs_json = bson_string_new ("");
for (i = 0; i < n_docs; i++) {
doc_json = bson_as_json (&docs[i], NULL);
Expand Down
3 changes: 2 additions & 1 deletion src/libmongoc/tests/test-libmongoc.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -407,13 +407,14 @@ log_handler (mongoc_log_level_t log_level,
suite = (TestSuite *) user_data;

if (log_level < MONGOC_LOG_LEVEL_INFO) {
bson_mutex_lock (&captured_logs_mutex);
if (capturing_logs) {
log_entry = log_entry_create (log_level, message);
bson_mutex_lock (&captured_logs_mutex);
_mongoc_array_append_val (&captured_logs, log_entry);
bson_mutex_unlock (&captured_logs_mutex);
return;
}
bson_mutex_unlock (&captured_logs_mutex);

if (!suite->silent) {
mongoc_log_default_handler (log_level, log_domain, message, NULL);
Expand Down