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?
> >
> > 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.
> > 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");
