Re: [Qemu-devel] [PATCH V4 RESEND 09/22] net: multiqueue support

[Jason Wang]

On 02/13/2013 05:21 AM, Alexander Graf wrote:
> On 01.02.2013, at 08:39, Jason Wang 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. And a queue_index
>> were introduced in NetClientState to track its index. After this, each peers 
>> of
>> a NICState were abstracted as a queue.
>>
>> After this change, all NetClientState that belongs to the same backend/nic 
>> has
>> the same id. When use want to change the link status, all NetClientStates 
>> that
>> belongs to the same backend/nic will be also changed. When user want to 
>> delete
>> a device or netdev, all NetClientStates that belongs to the same backend/nic
>> will be deleted also. Changing or deleting an specific queue is not allowed.
>>
>> Signed-off-by: Jason Wang <address@hidden>
>> Signed-off-by: Michael S. Tsirkin <address@hidden>
>> ---
>> hw/dp8393x.c                |    2 +-
>> hw/mcf_fec.c                |    2 +-
>> hw/qdev-properties-system.c |   46 +++++++++++++++---
>> hw/qdev-properties.h        |    6 +-
>> include/net/net.h           |   18 +++++--
>> net/net.c                   |  113 
>> +++++++++++++++++++++++++++++++------------
>> 6 files changed, 139 insertions(+), 48 deletions(-)
>>
>> diff --git a/hw/dp8393x.c b/hw/dp8393x.c
>> index 0273fad..808157b 100644
>> --- a/hw/dp8393x.c
>> +++ b/hw/dp8393x.c
>> @@ -900,7 +900,7 @@ 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 909e32b..8e60f09 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.ncs[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-system.c b/hw/qdev-properties-system.c
>> index ce0f793..ce3af22 100644
>> --- a/hw/qdev-properties-system.c
>> +++ b/hw/qdev-properties-system.c
>> @@ -173,16 +173,47 @@ 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)
>> @@ -249,7 +280,8 @@ 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 ddcf774..20c67f3 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/include/net/net.h b/include/net/net.h
>> index 22adc99..43a045e 100644
>> --- a/include/net/net.h
>> +++ b/include/net/net.h
>> @@ -9,24 +9,32 @@
>> #include "migration/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);
>> @@ -60,10 +68,11 @@ struct NetClientState {
>>     char info_str[256];
>>     unsigned receive_disabled : 1;
>>     NetClientDestructor *destructor;
>> +    unsigned int queue_index;
>> };
>>
>> typedef struct NICState {
>> -    NetClientState nc;
>> +    NetClientState ncs[MAX_QUEUE_NUM];
>>     NICConf *conf;
>>     void *opaque;
>>     bool peer_deleted;
>> @@ -82,6 +91,7 @@ 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);
>> diff --git a/net/net.c b/net/net.c
>> index 98a1934..9806862 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -236,28 +236,44 @@ 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,
>> +                              NULL);
>> +        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)
>> @@ -271,9 +287,7 @@ 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);
> This breaks the following backends:
>
> hw/pcnet.c
> hw/spapr_llan.c
> hw/xen_nic.c
>
> Is this change on purpose? If so, please provide empty cleanup function 
> callbacks for the above targets.
>

Not on purpose, a guard is needed but empty cleanup function is also ok.

Thanks
> Alex
>