From 0a27aa263e6dc20da060aea925ef64aba15dabb0 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Sat, 6 Apr 2019 13:46:40 +0200 Subject: 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 --- include/osmocom/core/select.h | 1 + src/select.c | 20 +++++++++++++++++--- 2 files changed, 18 insertions(+), 3 deletions(-) diff --git a/include/osmocom/core/select.h b/include/osmocom/core/select.h index a200b6f3..92904e2f 100644 --- a/include/osmocom/core/select.h +++ b/include/osmocom/core/select.h @@ -52,6 +52,7 @@ void osmo_fd_unregister(struct osmo_fd *fd); void osmo_fd_close(struct osmo_fd *fd); int osmo_select_main(int polling); int osmo_select_main_ctx(int polling); +void osmo_select_init(void); struct osmo_fd *osmo_fd_get_by_fd(int fd); diff --git a/src/select.c b/src/select.c index 34a133c0..3d4803f7 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 @@ -308,6 +310,18 @@ struct osmo_fd *osmo_fd_get_by_fd(int fd) 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 -- cgit v1.2.3