select: Make file descriptor lists per-thread
In a multi-threaded environemnt, it's likely that each thread will have
its own, distinct set of file descriptors that it wants to watch.
Hence, let's make the osmo_fd_* functions configure not one global
list of file descriptors, but a thread-local list of file descriptors.
Change-Id: I5082ed3e500ad1a7516e1785bc57e008da2fac9a
diff --git a/src/select.c b/src/select.c
index 394a59d..b997122 100644
--- a/src/select.c
+++ b/src/select.c
@@ -50,9 +50,11 @@
*
* \file select.c */
-static int maxfd = 0;
-static LLIST_HEAD(osmo_fds);
-static int unregistered_count;
+/* keep a set of file descriptors per-thread, so that each thread can have its own
+ * distinct set of file descriptors to interact with */
+static __thread int maxfd = 0;
+static __thread struct llist_head osmo_fds; /* TLS cannot use LLIST_HEAD() */
+static __thread int unregistered_count;
/*! Set up an osmo-fd. Will not register it.
* \param[inout] ofd Osmo FD to be set-up
@@ -307,6 +309,18 @@
return NULL;
}
+/*! initialize the osmocom select abstraction for the current thread */
+void osmo_select_init(void)
+{
+ INIT_LLIST_HEAD(&osmo_fds);
+}
+
+/* ensure main thread always has pre-initialized osmo_fds */
+static __attribute__((constructor)) void on_dso_load_select(void)
+{
+ osmo_select_init();
+}
+
#ifdef HAVE_SYS_TIMERFD_H
#include <sys/timerfd.h>