> -----Original Message-----
> From: Yang, Zhiyong
> Sent: Wednesday, April 4, 2018 11:32 AM
> To: Tan, Jianfeng; dev@dpdk.org
> Cc: maxime.coque...@redhat.com; tho...@monjalon.net; Wang, Zhihong;
> Bie, Tiwei
> Subject: RE: [PATCH v4 1/1] net/virtio-user: add support for server mode
> 
> Hi Jiafeng,
> 
> Thanks for your review and comments firstly.
> Reply inline.
> 
> > -----Original Message-----
> > From: Tan, Jianfeng
> > Sent: Tuesday, April 3, 2018 11:16 PM
> > To: Yang, Zhiyong <zhiyong.y...@intel.com>; dev@dpdk.org
> > Cc: maxime.coque...@redhat.com; tho...@monjalon.net; Wang, Zhihong
> > <zhihong.w...@intel.com>; Bie, Tiwei <tiwei....@intel.com>
> > Subject: Re: [PATCH v4 1/1] net/virtio-user: add support for server mode
> >
> >
> >
> > On 4/3/2018 8:20 PM, zhiyong.y...@intel.com wrote:
> > > virtio-user adds support for server mode in this patch.
> > >
> > > Client mode vhost-user startup firstly, server mode virtio-user
> > > startups and creates the socket file to exchange vhost messages.
> > >
> > > If the connection is broken, client mode vhost-user can support to
> > > reconnect virtio-user.
> > >
> > > Server mode virtio-user supports many times' vhost-user reconnections
> > > with the same parameter configurations.
> > >
> > > Release note is updated in the patch.
> >
> > With current implementation, we have to enable LSC; or no chance to
> accept
> > the coming connection. We shall point this out.
> >
> Ok.
> 
> > And if possible, split this patch into multiple patches.
> >
> How to split?

I think it can be split into three:
- One for new dev parameter.
- One for server socket setup.
- One for LSC handling.

But it's not a big patch anyway, I'm OK if you think better to keep in one 
patch.

> 
> > >
> > > Signed-off-by: Zhiyong Yang <zhiyong.y...@intel.com>
> > > ---
> > >   doc/guides/rel_notes/release_18_05.rst           |   6 ++
> > >   drivers/net/virtio/virtio_user/vhost_user.c      |  64 ++++++++++++--
> > >   drivers/net/virtio/virtio_user/virtio_user_dev.c |  45 +++++++---
> > >   drivers/net/virtio/virtio_user/virtio_user_dev.h |   4 +
> > >   drivers/net/virtio/virtio_user_ethdev.c          | 103
> > +++++++++++++++++++++--
> > >   5 files changed, 194 insertions(+), 28 deletions(-)
> > >
> > > diff --git a/doc/guides/rel_notes/release_18_05.rst
> > > b/doc/guides/rel_notes/release_18_05.rst
> > > index 9cc77f893..f8897b2e9 100644
> > > --- a/doc/guides/rel_notes/release_18_05.rst
> > > +++ b/doc/guides/rel_notes/release_18_05.rst
> > > @@ -58,6 +58,12 @@ New Features
> > >     * Added support for NVGRE, VXLAN and GENEVE filters in flow API.
> > >     * Added support for DROP action in flow API.
> > >
> > > +* **Added support for virtio-user server mode.**
> > > +  In a container environment if the vhost-user backend restarts,
> > > +there's no way
> > > +  for it to reconnect to virtio-user. To address this, support for
> > > +server mode
> > > +  is added. In this mode the socket file is created by virtio-user,
> > > +which the
> > > +  backend connects to. This means that if the backend restarts, it
> > > +can reconnect
> > > +  to virtio-user and continue communications.
> > >
> > >   API Changes
> > >   -----------
> > > diff --git a/drivers/net/virtio/virtio_user/vhost_user.c
> > > b/drivers/net/virtio/virtio_user/vhost_user.c
> > > index 91c6449bb..1b3401d4f 100644
> > > --- a/drivers/net/virtio/virtio_user/vhost_user.c
> > > +++ b/drivers/net/virtio/virtio_user/vhost_user.c
> > > @@ -378,6 +378,50 @@ vhost_user_sock(struct virtio_user_dev *dev,
> > >           return 0;
> > >   }
> > >
> > > +static void
> > > +virtio_user_set_block(int fd, bool enabled)
> >
> > This is only used once, no need to abstract it into a function?
> 
> Ok.
> 
> >
> > > +{
> > > + int f;
> > > +
> > > + f = fcntl(fd, F_GETFL);
> > > + if (enabled)
> > > +         fcntl(fd, F_SETFL, f & ~O_NONBLOCK);
> > > + else
> > > +         fcntl(fd, F_SETFL, f | O_NONBLOCK); }
> > > +
> > > +#define MAX_VIRTIO_USER_BACKLOG 128
> >
> > We only allow one connection from vhost-user, so how about just make
> the
> > backlog queue length as 1?
> >
> > > +static int
> > > +virtio_user_start_server(struct virtio_user_dev *dev, struct
> > > +sockaddr_un *un) {
> > > + int ret;
> > > + int fd = dev->listenfd;
> > > + int connectfd;
> > > +
> > > + ret = bind(fd, (struct sockaddr *)un, sizeof(*un));
> > > + if (ret < 0) {
> > > +         PMD_DRV_LOG(ERR, "failed to bind to %s: %s; remove it and
> > try again\n",
> > > +                     dev->path, strerror(errno));
> > > +         goto err;
> > > + }
> > > + ret = listen(fd, MAX_VIRTIO_USER_BACKLOG);
> > > + if (ret < 0)
> > > +         goto err;
> > > +
> > > + connectfd = accept(fd, NULL, NULL);
> > > + if (connectfd >= 0)
> > > +         dev->connected = true;
> > > + else
> > > +         goto err;
> >
> > if (connectfd < 0)
> >          goto err;
> >
> > dev->connected = true;
> > dev->vhostfd = connectfd;
> > ...
> 
> Ok.
> 
> >
> > > +
> > > + dev->vhostfd = connectfd;
> > > + virtio_user_set_block(connectfd, true);
> > > + return 0;
> > > +err:
> > > + close(dev->listenfd);
> > > + return -1;
> > > +}
> > > +
> > >   /**
> > >    * Set up environment to talk with a vhost user backend.
> > >    *
> > > @@ -390,6 +434,7 @@ vhost_user_setup(struct virtio_user_dev *dev)
> > >   {
> > >           int fd;
> > >           int flag;
> > > + int ret = 0;
> > >           struct sockaddr_un un;
> > >
> > >           fd = socket(AF_UNIX, SOCK_STREAM, 0); @@ -405,14 +450,21 @@
> > > vhost_user_setup(struct virtio_user_dev *dev)
> > >           memset(&un, 0, sizeof(un));
> > >           un.sun_family = AF_UNIX;
> > >           snprintf(un.sun_path, sizeof(un.sun_path), "%s", dev->path);
> > > - if (connect(fd, (struct sockaddr *)&un, sizeof(un)) < 0) {
> > > -         PMD_DRV_LOG(ERR, "connect error, %s", strerror(errno));
> > > -         close(fd);
> > > -         return -1;
> > > +
> > > + if (dev->is_server) {
> > > +         dev->listenfd = fd;
> > > +         ret = virtio_user_start_server(dev, &un);
> > > + } else {
> > > +         dev->vhostfd = fd;
> > > +         if (connect(fd, (struct sockaddr *)&un, sizeof(un)) < 0) {
> > > +                 PMD_DRV_LOG(ERR, "connect error, %s",
> > strerror(errno));
> > > +                 close(fd);
> > > +                 return -1;
> > > +         }
> > > +         dev->connected = true;
> > >           }
> > >
> > > - dev->vhostfd = fd;
> > > - return 0;
> > > + return ret;
> > >   }
> > >
> > >   static int
> > > diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> > > b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> > > index f90fee9e5..dd9fa9bdf 100644
> > > --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> > > +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> > > @@ -142,6 +142,9 @@ int virtio_user_stop_device(struct
> virtio_user_dev
> > *dev)
> > >   {
> > >           uint32_t i;
> > >
> > > + if (!dev->connected)
> > > +         return -1;
> > > +
> > >           for (i = 0; i < dev->max_queue_pairs; ++i)
> > >                   dev->ops->enable_qp(dev, i, 0);
> > >
> > > @@ -267,21 +270,27 @@ virtio_user_dev_setup(struct virtio_user_dev
> > *dev)
> > >           dev->vhostfds = NULL;
> > >           dev->tapfds = NULL;
> >
> > Add a check here:
> > if (dev->is_server && !is_vhost_user_by_type(dev->path))
> >          return error;
> 
> Ok.
> 
> >
> > >
> > > - if (is_vhost_user_by_type(dev->path)) {
> > > -         dev->ops = &ops_user;
> > > + if (dev->is_server) {
> > > +         dev->ops = &ops_user;/* server mode only supports vhost
> > user*/
> > >           } else {
> > > -         dev->ops = &ops_kernel;
> > > -
> > > -         dev->vhostfds = malloc(dev->max_queue_pairs *
> > sizeof(int));
> > > -         dev->tapfds = malloc(dev->max_queue_pairs * sizeof(int));
> > > -         if (!dev->vhostfds || !dev->tapfds) {
> > > -                 PMD_INIT_LOG(ERR, "Failed to malloc");
> > > -                 return -1;
> > > -         }
> > > -
> > > -         for (q = 0; q < dev->max_queue_pairs; ++q) {
> > > -                 dev->vhostfds[q] = -1;
> > > -                 dev->tapfds[q] = -1;
> > > +         if (is_vhost_user_by_type(dev->path)) {
> > > +                 dev->ops = &ops_user;
> > > +         } else {
> > > +                 dev->ops = &ops_kernel;
> > > +
> > > +                 dev->vhostfds = malloc(dev->max_queue_pairs *
> > > +                                        sizeof(int));
> > > +                 dev->tapfds = malloc(dev->max_queue_pairs *
> > > +                                      sizeof(int));
> > > +                 if (!dev->vhostfds || !dev->tapfds) {
> > > +                         PMD_INIT_LOG(ERR, "Failed to malloc");
> > > +                         return -1;
> > > +                 }
> > > +
> > > +                 for (q = 0; q < dev->max_queue_pairs; ++q) {
> > > +                         dev->vhostfds[q] = -1;
> > > +                         dev->tapfds[q] = -1;
> > > +                 }
> > >                   }
> > >           }
> > >
> > > @@ -388,6 +397,11 @@ virtio_user_dev_uninit(struct virtio_user_dev
> > > *dev)
> > >
> > >           close(dev->vhostfd);
> > >
> > > + if (dev->is_server && dev->listenfd >= 0) {
> > > +         close(dev->listenfd);
> > > +         dev->listenfd = -1;
> > > + }
> > > + dev->connected = false;
> > >           if (dev->vhostfds) {
> > >                   for (i = 0; i < dev->max_queue_pairs; ++i)
> > >                           close(dev->vhostfds[i]);
> > > @@ -396,6 +410,9 @@ virtio_user_dev_uninit(struct virtio_user_dev
> *dev)
> > >           }
> > >
> > >           free(dev->ifname);
> > > +
> > > + if (dev->is_server)
> > > +         unlink(dev->path);
> > >   }
> > >
> > >   static uint8_t
> > > diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.h
> > > b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> > > index 64467b4f9..68056720d 100644
> > > --- a/drivers/net/virtio/virtio_user/virtio_user_dev.h
> > > +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.h
> > > @@ -6,6 +6,7 @@
> > >   #define _VIRTIO_USER_DEV_H
> > >
> > >   #include <limits.h>
> > > +#include <stdbool.h>
> > >   #include "../virtio_pci.h"
> > >   #include "../virtio_ring.h"
> > >   #include "vhost.h"
> > > @@ -13,6 +14,9 @@
> > >   struct virtio_user_dev {
> > >           /* for vhost_user backend */
> > >           int             vhostfd;
> > > + int             listenfd;   /* listening fd */
> > > + bool            connected;  /* connection status */
> >
> > Seems not necessary to add this field; as the connection status can be
> > deduced from (vhostfd>=0)
> 
> Ok, remove it.
> 
> >
> > > + bool            is_server;  /* server or client mode */
> > >
> > >           /* for vhost_kernel backend */
> > >           char            *ifname;
> > > diff --git a/drivers/net/virtio/virtio_user_ethdev.c
> > > b/drivers/net/virtio/virtio_user_ethdev.c
> > > index 263649006..5b8c8e291 100644
> > > --- a/drivers/net/virtio/virtio_user_ethdev.c
> > > +++ b/drivers/net/virtio/virtio_user_ethdev.c
> > > @@ -24,15 +24,76 @@
> > >   #define virtio_user_get_dev(hw) \
> > >           ((struct virtio_user_dev *)(hw)->virtio_user_dev)
> > >
> > > +static void
> > > +virtio_user_server_reconnection(struct virtio_user_dev *dev)
> >
> > s/reconnection/reconnect?
> >
> 
> Ok, Good Suggestion.
> 
> > > +{
> > > + int ret;
> > > + int flag;
> > > + int connectfd;
> > > + struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
> > > +
> > > + if (dev->connected)
> > > +         return;
> > > +
> > > + connectfd = accept(dev->listenfd, NULL, NULL);
> > > + if (connectfd < 0)
> > > +         return;
> > > +
> > > + dev->vhostfd = connectfd;
> > > + flag = fcntl(connectfd, F_GETFD);
> > > + fcntl(connectfd, F_SETFL, flag & ~O_NONBLOCK);
> > > +
> > > + ret = virtio_user_start_device(dev);
> > > + if (ret < 0)
> > > +         return;
> > > +
> > > + if (eth_dev->data->dev_flags & RTE_ETH_DEV_INTR_LSC) {
> > > +         if (rte_intr_disable(eth_dev->intr_handle) < 0) {
> > > +                 PMD_DRV_LOG(ERR, "interrupt disable failed");
> > > +                 return;
> > > +         }
> > > +         rte_intr_callback_unregister(eth_dev->intr_handle,
> > > +                                      virtio_interrupt_handler,
> > > +                                      eth_dev);
> > > +         eth_dev->intr_handle->fd = connectfd;
> > > +         rte_intr_callback_register(eth_dev->intr_handle,
> > > +                                    virtio_interrupt_handler, eth_dev);
> > > +
> > > +         if (rte_intr_enable(eth_dev->intr_handle) < 0) {
> > > +                 PMD_DRV_LOG(ERR, "interrupt enable failed");
> > > +                 return;
> > > +         }
> > > + }
> > > + dev->connected = true;
> > > + PMD_INIT_LOG(NOTICE, "server mode virtio-user reconnection
> > > +succeeds!"); }
> > > +
> > >   static void
> > >   virtio_user_delayed_handler(void *param)
> > >   {
> > >           struct virtio_hw *hw = (struct virtio_hw *)param;
> > > - struct rte_eth_dev *dev = &rte_eth_devices[hw->port_id];
> > > + struct rte_eth_dev *eth_dev = &rte_eth_devices[hw->port_id];
> > > + struct virtio_user_dev *dev = virtio_user_get_dev(hw);
> > >
> > > - rte_intr_callback_unregister(dev->intr_handle,
> > > -                              virtio_interrupt_handler,
> > > -                              dev);
> > > + if (rte_intr_disable(eth_dev->intr_handle) < 0) {
> > > +         PMD_DRV_LOG(ERR, "interrupt disable failed");
> > > +         return;
> > > + }
> > > + rte_intr_callback_unregister(eth_dev->intr_handle,
> > > +                              virtio_interrupt_handler, eth_dev);
> > > + if (dev->is_server) {
> > > +         if (dev->vhostfd >= 0) {
> > > +                 close(dev->vhostfd);
> > > +                 dev->vhostfd = -1;
> > > +         }
> > > +         eth_dev->intr_handle->fd = dev->listenfd;
> > > +         rte_intr_callback_register(eth_dev->intr_handle,
> > > +                                    virtio_interrupt_handler, eth_dev);
> > > +         if (rte_intr_enable(eth_dev->intr_handle) < 0) {
> > > +                 PMD_DRV_LOG(ERR, "interrupt enable failed");
> > > +                 return;
> > > +         }
> > > + }
> > >   }
> > >
> > >   static void
> > > @@ -65,8 +126,7 @@ virtio_user_read_dev_config(struct virtio_hw *hw,
> > size_t offset,
> > >                           r = recv(dev->vhostfd, buf, 128, MSG_PEEK);
> >
> > As server mode and the connection is not connected, vhostfd is -1 now,
> then
> > r < 0 and errno is EBADF, how could it go into server handling in the "else 
> > if"
> > block?
> >
> 
> I think I don't catch you.  When server mode, if vhostfd = -1,
> if (dev->vhostfd >= 0)  is false, so, the code will goto to check else if 
> (dev->is_server)
> to handle server mode.

I'm sorry, I overlooked the " if (dev->vhostfd >= 0)", you are right!

Thanks,
Jianfeng

> 
> > >                           if (r == 0 || (r < 0 && errno != EAGAIN)) {
> > >                                   dev->status &= (~VIRTIO_NET_S_LINK_UP);
> > > -                         PMD_DRV_LOG(ERR, "virtio-user port %u is
> > down",
> > > -                                     hw->port_id);
> > > +
> > >                                   /* Only client mode is available now. 
> > > Once
> > the
> >
> > Can you also correct this note as we support server mode now?
> 
> Ok.
> >
> > >                                    * connection is broken, it can never 
> > > be up
> > >                                    * again. Besides, this function could 
> > > be called
> > @@ -74,9
> > > +134,14 @@ virtio_user_read_dev_config(struct virtio_hw *hw, size_t
> > offset,
> > >                                    * callback cannot be unregistered 
> > > here, set
> > an
> > >                                    * alarm to do it.
> > >                                    */
> > > -                         rte_eal_alarm_set(1,
> > > +                         if (dev->connected) {
> > > +                                 dev->connected = false;
> > > +                                 PMD_DRV_LOG(ERR, "virtio-user
> > port %u is down",
> > > +                                             hw->port_id);
> > > +                                 rte_eal_alarm_set(1,
> > >
> > virtio_user_delayed_handler,
> > >                                                     (void *)hw);
> > > +                         }
> > >                           } else {
> > >                                   dev->status |= VIRTIO_NET_S_LINK_UP;
> > >                           }
> > > @@ -85,7 +150,10 @@ virtio_user_read_dev_config(struct virtio_hw
> *hw,
> > size_t offset,
> > >                                   PMD_DRV_LOG(ERR, "error clearing
> > O_NONBLOCK flag");
> > >                                   return;
> > >                           }
> > > -         }
> > > +
> > > +         } else if (dev->is_server)
> > > +                 virtio_user_server_reconnection(dev);
> > > +
> > >                   *(uint16_t *)dst = dev->status;
> > >           }
> > >
> > > @@ -278,12 +346,15 @@ static const char *valid_args[] = {
> > >           VIRTIO_USER_ARG_QUEUE_SIZE,
> > >   #define VIRTIO_USER_ARG_INTERFACE_NAME "iface"
> > >           VIRTIO_USER_ARG_INTERFACE_NAME,
> > > +#define VIRTIO_USER_ARG_SERVER_MODE "server"
> > > + VIRTIO_USER_ARG_SERVER_MODE,
> > >           NULL
> > >   };
> > >
> > >   #define VIRTIO_USER_DEF_CQ_EN   0
> > >   #define VIRTIO_USER_DEF_Q_NUM   1
> > >   #define VIRTIO_USER_DEF_Q_SZ    256
> > > +#define VIRTIO_USER_DEF_SERVER_MODE      0
> > >
> > >   static int
> > >   get_string_arg(const char *key __rte_unused, @@ -378,10 +449,12 @@
> > > virtio_user_pmd_probe(struct rte_vdev_device *dev)
> > >           uint64_t queues = VIRTIO_USER_DEF_Q_NUM;
> > >           uint64_t cq = VIRTIO_USER_DEF_CQ_EN;
> > >           uint64_t queue_size = VIRTIO_USER_DEF_Q_SZ;
> > > + uint64_t server_mode = VIRTIO_USER_DEF_SERVER_MODE;
> > >           char *path = NULL;
> > >           char *ifname = NULL;
> > >           char *mac_addr = NULL;
> > >           int ret = -1;
> > > + struct virtio_user_dev *vu_dev = NULL;
> > >
> > >           kvlist = rte_kvargs_parse(rte_vdev_device_args(dev), 
> > > valid_args);
> > >           if (!kvlist) {
> > > @@ -445,6 +518,15 @@ virtio_user_pmd_probe(struct rte_vdev_device
> > *dev)
> > >                   }
> > >           }
> > >
> > > + if (rte_kvargs_count(kvlist, VIRTIO_USER_ARG_SERVER_MODE) == 1)
> > {
> > > +         if (rte_kvargs_process(kvlist,
> > VIRTIO_USER_ARG_SERVER_MODE,
> > > +                                &get_integer_arg, &server_mode) < 0) {
> > > +                 PMD_INIT_LOG(ERR, "error to parse %s",
> > > +                              VIRTIO_USER_ARG_SERVER_MODE);
> > > +                 goto end;
> > > +         }
> > > + }
> > > +
> > >           if (rte_kvargs_count(kvlist, VIRTIO_USER_ARG_CQ_NUM) == 1) {
> > >                   if (rte_kvargs_process(kvlist, VIRTIO_USER_ARG_CQ_NUM,
> > >                                          &get_integer_arg, &cq) < 0) { @@ 
> > > -476,6
> > +558,11 @@
> > > virtio_user_pmd_probe(struct rte_vdev_device *dev)
> > >                   }
> > >
> > >                   hw = eth_dev->data->dev_private;
> > > +         vu_dev = virtio_user_get_dev(hw);
> > > +         if (server_mode == 1)
> > > +                 vu_dev->is_server = true;
> > > +         else
> > > +                 vu_dev->is_server = false;
> > >                   if (virtio_user_dev_init(hw->virtio_user_dev, path, 
> > > queues,
> > cq,
> > >                                    queue_size, mac_addr, &ifname) < 0) {
> > >                           PMD_INIT_LOG(ERR, "virtio_user_dev_init fails");

Reply via email to