From: Jérémie Galarneau Date: Wed, 14 Feb 2018 21:14:21 +0000 (-0500) Subject: Assert that the consumer lock is held while sending FDs to consumerd X-Git-Tag: v2.11.0-rc1~402 X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=05dac5980b42afe7b0334b009f43b4e3ba98a319 Assert that the consumer lock is held while sending FDs to consumerd The consumer_data lock must be held during the communications between the consumerd and sessiond. The consumer_data lock is refered-to by each consumer_socket instance; they point to their consumer's global data lock. The lock can't be taken in consumer_send_msg() or consumer_send_fds() since we want to protect a complete "transaction". Some commands require both functions to be called and we want to hold the lock over the duration of both calls to protect against other threads initiating a communication between the two calls. Signed-off-by: Jérémie Galarneau --- diff --git a/src/bin/lttng-sessiond/consumer.c b/src/bin/lttng-sessiond/consumer.c index bd9048bf5..ced965dee 100644 --- a/src/bin/lttng-sessiond/consumer.c +++ b/src/bin/lttng-sessiond/consumer.c @@ -739,6 +739,7 @@ int consumer_send_fds(struct consumer_socket *sock, int *fds, size_t nb_fd) assert(fds); assert(sock); assert(nb_fd > 0); + assert(pthread_mutex_trylock(sock->lock) == EBUSY); ret = lttcomm_send_fds_unix_sock(*sock->fd_ptr, fds, nb_fd); if (ret < 0) {