Function kcov_thread_dtor

freebsd/kern/kern_kcov.c:517–557

}

static void
kcov_thread_dtor(void *arg __unused, struct thread *td)
{
	struct kcov_info *info;

	info = td->td_kcov_info;
	if (info == NULL)
		return;

	mtx_lock_spin(&kcov_lock);
	KASSERT(active_count > 0, ("%s: Open count is zero", __func__));
	active_count--;
	if (active_count == 0) {
		cov_unregister_pc();
		cov_unregister_cmp();
	}
	td->td_kcov_info = NULL;
	if (info->state != KCOV_STATE_DYING) {
		/*
		 * The kcov file is still open. Mark it as unused and
		 * wait for it to be closed before cleaning up.
		 */
		atomic_store_int(&info->state, KCOV_STATE_READY);
		atomic_thread_fence_seq_cst();
		/* This info struct is unused */
		info->thread = NULL;
		mtx_unlock_spin(&kcov_lock);
		return;
	}
	mtx_unlock_spin(&kcov_lock);

	/*
	 * We can safely clean up the info struct as it is in the
	 * KCOV_STATE_DYING state where the info struct is associated with
	 * the current thread that's about to exit.
	 *
	 * The KCOV_STATE_DYING stops new threads from using it.
	 * It also stops the current thread from trying to use the info struct.
	 */
	kcov_free(info);
}

static void
kcov_init(const void *unused)