Re: [PATCH 05/12] net: multiqueue support

[Blue Swirl <blauwirbel@gmail.com>]

On Fri, Dec 28, 2012 at 10:31 AM, Jason Wang <jasowang@redhat.com> wrote:
> This patch adds basic multiqueue support for qemu. The idea is simple, an array
> of NetClientStates were introduced in NICState, parse_netdev() were extended to
> find and match all NetClientStates belongs to the backend and place their
> pointers in NICConf. Then qemu_new_nic can setup a N:N mapping between NICStates
> that belongs to a nic and NICStates belongs to the netdev. After this, each
> peers of a NICStaet were abstracted as a queue.
>
> To adapt this change, set_link/netdev_del command will find all the
> NetClientStates of a nic or a netdev, and change all their state in one run.
>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
>  hw/dp8393x.c         |    2 +-
>  hw/mcf_fec.c         |    2 +-
>  hw/qdev-properties.c |   46 +++++++++++--
>  hw/qdev-properties.h |    6 +-
>  net.c                |  172 +++++++++++++++++++++++++++++++++++++-------------
>  net.h                |   27 +++++++-
>  6 files changed, 195 insertions(+), 60 deletions(-)
>
> diff --git a/hw/dp8393x.c b/hw/dp8393x.c
> index 8f20a4a..fad0837 100644
> --- a/hw/dp8393x.c
> +++ b/hw/dp8393x.c
> @@ -899,7 +899,7 @@ void dp83932_init(NICInfo *nd, hwaddr base, int it_shift,
>      s->regs[SONIC_SR] = 0x0004; /* only revision recognized by Linux */
>
>      s->conf.macaddr = nd->macaddr;
> -    s->conf.peer = nd->netdev;
> +    s->conf.peers.ncs[0] = nd->netdev;
>
>      s->nic = qemu_new_nic(&net_dp83932_info, &s->conf, nd->model, nd->name, s);
>
> diff --git a/hw/mcf_fec.c b/hw/mcf_fec.c
> index 7fc89b5..c298bec 100644
> --- a/hw/mcf_fec.c
> +++ b/hw/mcf_fec.c
> @@ -472,7 +472,7 @@ void mcf_fec_init(MemoryRegion *sysmem, NICInfo *nd,
>      memory_region_add_subregion(sysmem, base, &s->iomem);
>
>      s->conf.macaddr = nd->macaddr;
> -    s->conf.peer = nd->netdev;
> +    s->conf.peers[0] = nd->netdev;
>
>      s->nic = qemu_new_nic(&net_mcf_fec_info, &s->conf, nd->model, nd->name, s);
>
> diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
> index 81d901c..6e45def 100644
> --- a/hw/qdev-properties.c
> +++ b/hw/qdev-properties.c
> @@ -585,16 +585,47 @@ PropertyInfo qdev_prop_chr = {
>
>  static int parse_netdev(DeviceState *dev, const char *str, void **ptr)
>  {
> -    NetClientState *netdev = qemu_find_netdev(str);
> +    NICPeers *peers_ptr = (NICPeers *)ptr;
> +    NICConf *conf = container_of(peers_ptr, NICConf, peers);
> +    NetClientState **ncs = peers_ptr->ncs;
> +    NetClientState *peers[MAX_QUEUE_NUM];
> +    int queues, i = 0;
> +    int ret;
>
> -    if (netdev == NULL) {
> -        return -ENOENT;
> +    queues = qemu_find_net_clients_except(str, peers,
> +                                          NET_CLIENT_OPTIONS_KIND_NIC,
> +                                          MAX_QUEUE_NUM);
> +    if (queues == 0) {
> +        ret = -ENOENT;
> +        goto err;
>      }
> -    if (netdev->peer) {
> -        return -EEXIST;
> +
> +    if (queues > MAX_QUEUE_NUM) {
> +        ret = -E2BIG;
> +        goto err;
> +    }
> +
> +    for (i = 0; i < queues; i++) {
> +        if (peers[i] == NULL) {
> +            ret = -ENOENT;
> +            goto err;
> +        }
> +
> +        if (peers[i]->peer) {
> +            ret = -EEXIST;
> +            goto err;
> +        }
> +
> +        ncs[i] = peers[i];
> +        ncs[i]->queue_index = i;
>      }
> -    *ptr = netdev;
> +
> +    conf->queues = queues;
> +
>      return 0;
> +
> +err:
> +    return ret;
>  }
>
>  static const char *print_netdev(void *ptr)
> @@ -661,7 +692,8 @@ static void set_vlan(Object *obj, Visitor *v, void *opaque,
>  {
>      DeviceState *dev = DEVICE(obj);
>      Property *prop = opaque;
> -    NetClientState **ptr = qdev_get_prop_ptr(dev, prop);
> +    NICPeers *peers_ptr = qdev_get_prop_ptr(dev, prop);
> +    NetClientState **ptr = &peers_ptr->ncs[0];
>      Error *local_err = NULL;
>      int32_t id;
>      NetClientState *hubport;
> diff --git a/hw/qdev-properties.h b/hw/qdev-properties.h
> index 5b046ab..2d90848 100644
> --- a/hw/qdev-properties.h
> +++ b/hw/qdev-properties.h
> @@ -31,7 +31,7 @@ extern PropertyInfo qdev_prop_pci_host_devaddr;
>          .name      = (_name),                                    \
>          .info      = &(_prop),                                   \
>          .offset    = offsetof(_state, _field)                    \
> -            + type_check(_type,typeof_field(_state, _field)),    \
> +            + type_check(_type, typeof_field(_state, _field)),   \
>          }
>  #define DEFINE_PROP_DEFAULT(_name, _state, _field, _defval, _prop, _type) { \
>          .name      = (_name),                                           \
> @@ -77,9 +77,9 @@ extern PropertyInfo qdev_prop_pci_host_devaddr;
>  #define DEFINE_PROP_STRING(_n, _s, _f)             \
>      DEFINE_PROP(_n, _s, _f, qdev_prop_string, char*)
>  #define DEFINE_PROP_NETDEV(_n, _s, _f)             \
> -    DEFINE_PROP(_n, _s, _f, qdev_prop_netdev, NetClientState*)
> +    DEFINE_PROP(_n, _s, _f, qdev_prop_netdev, NICPeers)
>  #define DEFINE_PROP_VLAN(_n, _s, _f)             \
> -    DEFINE_PROP(_n, _s, _f, qdev_prop_vlan, NetClientState*)
> +    DEFINE_PROP(_n, _s, _f, qdev_prop_vlan, NICPeers)
>  #define DEFINE_PROP_DRIVE(_n, _s, _f) \
>      DEFINE_PROP(_n, _s, _f, qdev_prop_drive, BlockDriverState *)
>  #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
> diff --git a/net.c b/net.c
> index 97ee542..4ceba33 100644
> --- a/net.c
> +++ b/net.c
> @@ -181,17 +181,12 @@ static char *assign_name(NetClientState *nc1, const char *model)
>      return g_strdup(buf);
>  }
>
> -NetClientState *qemu_new_net_client(NetClientInfo *info,
> -                                    NetClientState *peer,
> -                                    const char *model,
> -                                    const char *name)
> +void qemu_net_client_setup(NetClientState *nc,
> +                           NetClientInfo *info,
> +                           NetClientState *peer,
> +                           const char *model,
> +                           const char *name)
>  {
> -    NetClientState *nc;
> -
> -    assert(info->size >= sizeof(NetClientState));
> -
> -    nc = g_malloc0(info->size);
> -
>      nc->info = info;
>      nc->model = g_strdup(model);
>      if (name) {
> @@ -208,6 +203,20 @@ NetClientState *qemu_new_net_client(NetClientInfo *info,
>      QTAILQ_INSERT_TAIL(&net_clients, nc, next);
>
>      nc->send_queue = qemu_new_net_queue(nc);
> +}
> +
> +
> +NetClientState *qemu_new_net_client(NetClientInfo *info,
> +                                    NetClientState *peer,
> +                                    const char *model,
> +                                    const char *name)
> +{
> +    NetClientState *nc;
> +
> +    assert(info->size >= sizeof(NetClientState));
> +
> +    nc = g_malloc0(info->size);
> +    qemu_net_client_setup(nc, info, peer, model, name);
>
>      return nc;
>  }
> @@ -219,28 +228,43 @@ NICState *qemu_new_nic(NetClientInfo *info,
>                         void *opaque)
>  {
>      NetClientState *nc;
> +    NetClientState **peers = conf->peers.ncs;
>      NICState *nic;
> +    int i;
>
>      assert(info->type == NET_CLIENT_OPTIONS_KIND_NIC);
>      assert(info->size >= sizeof(NICState));
>
> -    nc = qemu_new_net_client(info, conf->peer, model, name);
> +    nc = qemu_new_net_client(info, peers[0], model, name);
> +    nc->queue_index = 0;
>
>      nic = qemu_get_nic(nc);
>      nic->conf = conf;
>      nic->opaque = opaque;
>
> +    for (i = 1; i < conf->queues; i++) {
> +        qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, nc->name);
> +        nic->ncs[i].queue_index = i;
> +    }
> +
>      return nic;
>  }
>
> +NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
> +{
> +    return &nic->ncs[queue_index];
> +}
> +
>  NetClientState *qemu_get_queue(NICState *nic)
>  {
> -    return &nic->nc;
> +    return qemu_get_subqueue(nic, 0);
>  }
>
>  NICState *qemu_get_nic(NetClientState *nc)
>  {
> -    return DO_UPCAST(NICState, nc, nc);
> +    NetClientState *nc0 = nc - nc->queue_index;
> +
> +    return DO_UPCAST(NICState, ncs[0], nc0);
>  }
>
>  void *qemu_get_nic_opaque(NetClientState *nc)
> @@ -254,12 +278,10 @@ static void qemu_cleanup_net_client(NetClientState *nc)
>  {
>      QTAILQ_REMOVE(&net_clients, nc, next);
>
> -    if (nc->info->cleanup) {
> -        nc->info->cleanup(nc);
> -    }
> +    nc->info->cleanup(nc);
>  }
>
> -static void qemu_free_net_client(NetClientState *nc)
> +static void qemu_free_net_client(NetClientState *nc, bool free)
>  {
>      if (nc->send_queue) {
>          qemu_del_net_queue(nc->send_queue);
> @@ -269,11 +291,24 @@ static void qemu_free_net_client(NetClientState *nc)
>      }
>      g_free(nc->name);
>      g_free(nc->model);
> -    g_free(nc);
> +
> +    if (free)

Missing braces.

> +        g_free(nc);
>  }
>
>  void qemu_del_net_client(NetClientState *nc)
>  {
> +    NetClientState *ncs[MAX_QUEUE_NUM];
> +    int queues, i;
> +
> +    /* If the NetClientState belongs to a multiqueue backend, we will change all
> +     * other NetClientStates also.
> +     */
> +    queues = qemu_find_net_clients_except(nc->name, ncs,
> +                                          NET_CLIENT_OPTIONS_KIND_NIC,
> +                                          MAX_QUEUE_NUM);
> +    assert(queues != 0);
> +
>      /* If there is a peer NIC, delete and cleanup client, but do not free. */
>      if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
>          NICState *nic = qemu_get_nic(nc->peer);
> @@ -281,34 +316,50 @@ void qemu_del_net_client(NetClientState *nc)
>              return;
>          }
>          nic->peer_deleted = true;
> -        /* Let NIC know peer is gone. */
> -        nc->peer->link_down = true;
> +
> +        for (i = 0; i < queues; i++) {
> +            ncs[i]->peer->link_down = true;
> +        }
> +
>          if (nc->peer->info->link_status_changed) {
>              nc->peer->info->link_status_changed(nc->peer);
>          }
> -        qemu_cleanup_net_client(nc);
> +
> +        for (i = 0; i < queues; i++) {
> +            qemu_cleanup_net_client(ncs[i]);
> +        }
> +
>          return;
>      }
>
>      assert(nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC);
>
> -    qemu_cleanup_net_client(nc);
> -    qemu_free_net_client(nc);
> +    for (i = 0; i < queues; i++) {
> +        qemu_cleanup_net_client(ncs[i]);
> +        qemu_free_net_client(ncs[i], true);
> +    }
>  }
>
>  void qemu_del_nic(NICState *nic)
>  {
> -    NetClientState *nc = qemu_get_queue(nic);
> +    int i, queues = nic->conf->queues;
> +
>      /* If this is a peer NIC and peer has already been deleted, free it now. */
> -    if (nc->peer && nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
> -        NICState *nic = qemu_get_nic(nc);
> -        if (nic->peer_deleted) {
> -            qemu_free_net_client(nc->peer);
> +    if (nic->peer_deleted) {
> +        for (i = 0; i < queues; i++) {
> +            qemu_free_net_client(qemu_get_subqueue(nic, i)->peer, true);
>          }
>      }
>
> -    qemu_cleanup_net_client(nc);
> -    qemu_free_net_client(nc);
> +    for (i = 1; i < queues; i++) {
> +        NetClientState *nc = qemu_get_subqueue(nic, i);
> +
> +        qemu_cleanup_net_client(nc);
> +        qemu_free_net_client(nc, false);
> +    }
> +
> +    qemu_cleanup_net_client(qemu_get_subqueue(nic, 0));
> +    qemu_free_net_client(qemu_get_subqueue(nic, 0), true);
>  }
>
>  void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
> @@ -317,7 +368,9 @@ void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
>
>      QTAILQ_FOREACH(nc, &net_clients, next) {
>          if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
> -            func(qemu_get_nic(nc), opaque);
> +            if (nc->queue_index == 0) {
> +                func(qemu_get_nic(nc), opaque);
> +            }
>          }
>      }
>  }
> @@ -507,6 +560,27 @@ NetClientState *qemu_find_netdev(const char *id)
>      return NULL;
>  }
>
> +int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
> +                                 NetClientOptionsKind type, int max)
> +{
> +    NetClientState *nc;
> +    int ret = 0;
> +
> +    QTAILQ_FOREACH(nc, &net_clients, next) {
> +        if (nc->info->type == type) {
> +            continue;
> +        }
> +        if (!strcmp(nc->name, id)) {
> +            if (ret < max) {
> +                ncs[ret] = nc;
> +            }
> +            ret++;
> +        }
> +    }
> +
> +    return ret;
> +}
> +
>  static int nic_get_free_idx(void)
>  {
>      int index;
> @@ -873,8 +947,11 @@ void qmp_netdev_del(const char *id, Error **errp)
>
>  void print_net_client(Monitor *mon, NetClientState *nc)
>  {
> -    monitor_printf(mon, "%s: type=%s,%s\n", nc->name,
> -                   NetClientOptionsKind_lookup[nc->info->type], nc->info_str);
> +    monitor_printf(mon, "%s: index=%d,type=%s,%s,link=%s\n", nc->name,
> +                       nc->queue_index,
> +                       NetClientOptionsKind_lookup[nc->info->type],
> +                       nc->info_str,
> +                       nc->link_down ? "down" : "up");
>  }
>
>  void do_info_network(Monitor *mon)
> @@ -905,20 +982,23 @@ void do_info_network(Monitor *mon)
>
>  void qmp_set_link(const char *name, bool up, Error **errp)
>  {
> -    NetClientState *nc = NULL;
> +    NetClientState *ncs[MAX_QUEUE_NUM];
> +    NetClientState *nc;
> +    int queues, i;
>
> -    QTAILQ_FOREACH(nc, &net_clients, next) {
> -        if (!strcmp(nc->name, name)) {
> -            goto done;
> -        }
> -    }
> -done:
> -    if (!nc) {
> +    queues = qemu_find_net_clients_except(name, ncs,
> +                                          NET_CLIENT_OPTIONS_KIND_MAX,
> +                                          MAX_QUEUE_NUM);
> +
> +    if (queues == 0) {
>          error_set(errp, QERR_DEVICE_NOT_FOUND, name);
>          return;
>      }
> +    nc = ncs[0];
>
> -    nc->link_down = !up;
> +    for (i = 0; i < queues; i++) {
> +        ncs[i]->link_down = !up;
> +    }
>
>      if (nc->info->link_status_changed) {
>          nc->info->link_status_changed(nc);
> @@ -938,9 +1018,13 @@ done:
>
>  void net_cleanup(void)
>  {
> -    NetClientState *nc, *next_vc;
> +    NetClientState *nc;
>
> -    QTAILQ_FOREACH_SAFE(nc, &net_clients, next, next_vc) {
> +    /* We may del multiple entries during qemu_del_net_client(),
> +     * so QTAILQ_FOREACH_SAFE() is also not safe here.
> +     */
> +    while (!QTAILQ_EMPTY(&net_clients)) {
> +        nc = QTAILQ_FIRST(&net_clients);
>          if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
>              qemu_del_nic(qemu_get_nic(nc));
>          } else {
> diff --git a/net.h b/net.h
> index 0d53337..6ff1afc 100644
> --- a/net.h
> +++ b/net.h
> @@ -9,24 +9,32 @@
>  #include "vmstate.h"
>  #include "qapi-types.h"
>
> +#define MAX_QUEUE_NUM 1024
> +
>  struct MACAddr {
>      uint8_t a[6];
>  };
>
>  /* qdev nic properties */
>
> +typedef struct NICPeers {
> +    NetClientState *ncs[MAX_QUEUE_NUM];
> +} NICPeers;
> +
>  typedef struct NICConf {
>      MACAddr macaddr;
> -    NetClientState *peer;
> +    NICPeers peers;
>      int32_t bootindex;
> +    int32_t queues;
>  } NICConf;
>
>  #define DEFINE_NIC_PROPERTIES(_state, _conf)                            \
>      DEFINE_PROP_MACADDR("mac",   _state, _conf.macaddr),                \
> -    DEFINE_PROP_VLAN("vlan",     _state, _conf.peer),                   \
> -    DEFINE_PROP_NETDEV("netdev", _state, _conf.peer),                   \
> +    DEFINE_PROP_VLAN("vlan",     _state, _conf.peers),                   \
> +    DEFINE_PROP_NETDEV("netdev", _state, _conf.peers),                   \
>      DEFINE_PROP_INT32("bootindex", _state, _conf.bootindex, -1)
>
> +
>  /* Net clients */
>
>  typedef void (NetPoll)(NetClientState *, bool enable);
> @@ -58,16 +66,26 @@ struct NetClientState {
>      char *name;
>      char info_str[256];
>      unsigned receive_disabled : 1;
> +    unsigned int queue_index;
>  };
>
>  typedef struct NICState {
> -    NetClientState nc;
> +    NetClientState ncs[MAX_QUEUE_NUM];
>      NICConf *conf;
>      void *opaque;
>      bool peer_deleted;
>  } NICState;
>
>  NetClientState *qemu_find_netdev(const char *id);
> +int qemu_find_net_clients_except(const char *id,
> +                                 NetClientState **ncs,
> +                                 NetClientOptionsKind type,
> +                                 int max);
> +void qemu_net_client_setup(NetClientState *nc,
> +                           NetClientInfo *info,
> +                           NetClientState *peer,
> +                           const char *model,
> +                           const char *name);
>  NetClientState *qemu_new_net_client(NetClientInfo *info,
>                                      NetClientState *peer,
>                                      const char *model,
> @@ -78,6 +96,7 @@ NICState *qemu_new_nic(NetClientInfo *info,
>                         const char *name,
>                         void *opaque);
>  void qemu_del_nic(NICState *nic);
> +NetClientState *qemu_get_subqueue(NICState *nic, int queue_index);
>  NetClientState *qemu_get_queue(NICState *nic);
>  NICState *qemu_get_nic(NetClientState *nc);
>  void *qemu_get_nic_opaque(NetClientState *nc);
> --
> 1.7.1
>
>