qemu/hw/dataplane/event-poll.h
Stefan Hajnoczi 71973b0461 dataplane: add event loop
Outside the safety of the global mutex we need to poll on file
descriptors.  I found epoll(2) is a convenient way to do that, although
other options could replace this module in the future (such as an
AioContext-based loop or glib's GMainLoop).

One important feature of this small event loop implementation is that
the loop can be terminated in a thread-safe way.  This allows QEMU to
stop the data plane thread cleanly.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-01-02 15:56:21 +01:00

41 lines
1.1 KiB
C

/*
* Event loop with file descriptor polling
*
* Copyright 2012 IBM, Corp.
* Copyright 2012 Red Hat, Inc. and/or its affiliates
*
* Authors:
* Stefan Hajnoczi <stefanha@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef EVENT_POLL_H
#define EVENT_POLL_H
#include "qemu/event_notifier.h"
typedef struct EventHandler EventHandler;
typedef void EventCallback(EventHandler *handler);
struct EventHandler {
EventNotifier *notifier; /* eventfd */
EventCallback *callback; /* callback function */
};
typedef struct {
int epoll_fd; /* epoll(2) file descriptor */
EventNotifier stop_notifier; /* stop poll notifier */
EventHandler stop_handler; /* stop poll handler */
} EventPoll;
void event_poll_add(EventPoll *poll, EventHandler *handler,
EventNotifier *notifier, EventCallback *callback);
void event_poll_init(EventPoll *poll);
void event_poll_cleanup(EventPoll *poll);
void event_poll(EventPoll *poll);
void event_poll_notify(EventPoll *poll);
#endif /* EVENT_POLL_H */