numam-dpdk/lib/librte_vhost/fd_man.h
Tonghao Zhang d64c43773a vhost: add pipe event for optimizing negotiation
When vhost-user connects qemu successfully, dpdk will call
the vhost_user_add_connection to add unix socket fd to poll.
And fdset_add only set the socket fd to a fdentry while poll
may sleep now. In a general case, this is no problem. But if
we use hot update for vhost-user, most downtime of VMs network
is 750+ms. This patch adds pipe event, so after connections are
ok, dpdk rebuild the poll immediately. With this patch, the
most downtime is 20~30ms.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-03-30 17:25:45 +02:00

57 lines
1.1 KiB
C

/* SPDX-License-Identifier: BSD-3-Clause
* Copyright(c) 2010-2014 Intel Corporation
*/
#ifndef _FD_MAN_H_
#define _FD_MAN_H_
#include <stdint.h>
#include <pthread.h>
#include <poll.h>
#define MAX_FDS 1024
typedef void (*fd_cb)(int fd, void *dat, int *remove);
struct fdentry {
int fd; /* -1 indicates this entry is empty */
fd_cb rcb; /* callback when this fd is readable. */
fd_cb wcb; /* callback when this fd is writeable.*/
void *dat; /* fd context */
int busy; /* whether this entry is being used in cb. */
};
struct fdset {
struct pollfd rwfds[MAX_FDS];
struct fdentry fd[MAX_FDS];
pthread_mutex_t fd_mutex;
int num; /* current fd number of this fdset */
union pipefds {
struct {
int pipefd[2];
};
struct {
int readfd;
int writefd;
};
} u;
};
void fdset_init(struct fdset *pfdset);
int fdset_add(struct fdset *pfdset, int fd,
fd_cb rcb, fd_cb wcb, void *dat);
void *fdset_del(struct fdset *pfdset, int fd);
void *fdset_event_dispatch(void *arg);
int fdset_pipe_init(struct fdset *fdset);
void fdset_pipe_uninit(struct fdset *fdset);
void fdset_pipe_notify(struct fdset *fdset);
#endif