X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-ust-comm.c;h=8c864f8ce595621434cfac4a08dec1aa705d5671;hb=3b8b68e73ec9b2b3cf550048046d3f7f69050688;hp=12385dfca95762d32839b4e5917a92f8b82b4c58;hpb=dc43c97f077c92fd1d90c898496120c08ca571a7;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index 12385dfc..8c864f8c 100644
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -78,6 +78,12 @@ static sem_t constructor_wait;
  */
 static int sem_count = { 2 };
 
+/*
+ * Counting nesting within lttng-ust. Used to ensure that calling fork()
+ * from liblttng-ust does not execute the pre/post fork handlers.
+ */
+static int __thread lttng_ust_nest_count;
+
 /*
  * Info about socket and associated listener thread.
  */
@@ -469,7 +475,9 @@ int get_wait_shm(struct sock_info *sock_info, size_t mmap_size)
 	 * If the open failed because the file did not exist, try
 	 * creating it ourself.
 	 */
+	lttng_ust_nest_count++;
 	pid = fork();
+	lttng_ust_nest_count--;
 	if (pid > 0) {
 		int status;
 
@@ -883,15 +891,20 @@ void __attribute__((constructor)) lttng_ust_init(void)
 	sigfillset(&sig_all_blocked);
 	ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_parent_mask);
 	if (ret) {
-		PERROR("pthread_sigmask: %s", strerror(ret));
+		ERR("pthread_sigmask: %s", strerror(ret));
 	}
 
 	ret = pthread_create(&global_apps.ust_listener, NULL,
 			ust_listener_thread, &global_apps);
-
+	if (ret) {
+		ERR("pthread_create global: %s", strerror(ret));
+	}
 	if (local_apps.allowed) {
 		ret = pthread_create(&local_apps.ust_listener, NULL,
 				ust_listener_thread, &local_apps);
+		if (ret) {
+			ERR("pthread_create local: %s", strerror(ret));
+		}
 	} else {
 		handle_register_done(&local_apps);
 	}
@@ -899,7 +912,7 @@ void __attribute__((constructor)) lttng_ust_init(void)
 	/* Restore original signal mask in parent */
 	ret = pthread_sigmask(SIG_SETMASK, &orig_parent_mask, NULL);
 	if (ret) {
-		PERROR("pthread_sigmask: %s", strerror(ret));
+		ERR("pthread_sigmask: %s", strerror(ret));
 	}
 
 	switch (timeout_mode) {
@@ -975,12 +988,14 @@ void __attribute__((destructor)) lttng_ust_exit(void)
 	/* cancel threads */
 	ret = pthread_cancel(global_apps.ust_listener);
 	if (ret) {
-		ERR("Error cancelling global ust listener thread");
+		ERR("Error cancelling global ust listener thread: %s",
+			strerror(ret));
 	}
 	if (local_apps.allowed) {
 		ret = pthread_cancel(local_apps.ust_listener);
 		if (ret) {
-			ERR("Error cancelling local ust listener thread");
+			ERR("Error cancelling local ust listener thread: %s",
+				strerror(ret));
 		}
 	}
 	/*
@@ -1012,6 +1027,8 @@ void ust_before_fork(sigset_t *save_sigset)
 	sigset_t all_sigs;
 	int ret;
 
+	if (lttng_ust_nest_count)
+		return;
 	/* Disable signals */
 	sigfillset(&all_sigs);
 	ret = sigprocmask(SIG_BLOCK, &all_sigs, save_sigset);
@@ -1037,6 +1054,8 @@ static void ust_after_fork_common(sigset_t *restore_sigset)
 
 void ust_after_fork_parent(sigset_t *restore_sigset)
 {
+	if (lttng_ust_nest_count)
+		return;
 	DBG("process %d", getpid());
 	rcu_bp_after_fork_parent();
 	/* Release mutexes and reenable signals */
@@ -1054,6 +1073,8 @@ void ust_after_fork_parent(sigset_t *restore_sigset)
  */
 void ust_after_fork_child(sigset_t *restore_sigset)
 {
+	if (lttng_ust_nest_count)
+		return;
 	DBG("process %d", getpid());
 	/* Release urcu mutexes */
 	rcu_bp_after_fork_child();