MORE WORK

lib/event.c

@@ -1654,17 +1654,26 @@ static inline void thread_process_io_inner_loop(struct event_loop *m, unsigned i
  * Walks through file descriptor array looking for those pollfds whose .revents
  * field has something interesting. Deletes any invalid file descriptors.
  *
+ * Try to impart some impartiality to handling of reads.  The event
+ * system will cycle through the fd's available for being read
+ * giving each one a chance to go first.
+ *
  * @param m the thread master
  * @param num the number of active file descriptors (return value of poll())
  */
 static void thread_process_io(struct event_loop *m, unsigned int num)
 {
 	unsigned int ready = 0;
 	struct pollfd *pfds = m->handler.copy;
+	nfds_t last_read = m->last_read & m->handler.copycount;
 
-	for (nfds_t i = 0; i < m->handler.copycount && ready < num; ++i) {
-	  thread_process_io_inner_loop(m, num, pfds, &i, &ready);
-	}
+	for (nfds_t i = last_read; i < m->handler.copycount && ready < num; ++i)
+		thread_process_io_inner_loop(m, num, pfds, &i, &ready);
+
+	for (nfds_t i = 0; i < last_read && ready < num; ++i)
+		thread_process_io_inner_loop(m, num, pfds, &i, &ready);
+
+	m->last_read++;
 }
 
 /* Add all timers that have popped to the ready list. */

lib/frrevent.h

@@ -91,6 +91,8 @@ struct event_loop {
 	pthread_mutex_t mtx;
 	pthread_t owner;
 
+	nfds_t last_read;
+
 	bool ready_run_loop;
 	RUSAGE_T last_getrusage;
 };