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
This commit is contained in:
Harald Welte 2019-04-06 13:46:40 +02:00 committed by Harald Welte
parent ba5a9b9224
commit 7a010b10f7
2 changed files with 18 additions and 3 deletions

View File

@ -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);

View File

@ -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 @@ 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 <sys/timerfd.h>