Commit ffe6370c authored by Michael S. Tsirkin's avatar Michael S. Tsirkin Committed by Anthony Liguori
Browse files

qemu/net: flag to control the number of vectors a nic has 



Add an option to specify the number of MSI-X vectors for PCI NIC cards. This
can also be used to disable MSI-X, for compatibility with old qemu. This
option currently only affects virtio cards.

Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 566e2d3e

hw/virtio-net.c

+4 −1
Original line number Diff line number Diff line
@@ -745,7 +745,10 @@ VirtIODevice *virtio_net_init(DeviceState *dev) 
    n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);



    n->vlans = qemu_mallocz(MAX_VLAN >> 3);

    if (dev->nd->nvectors == NIC_NVECTORS_UNSPECIFIED)

        n->vdev.nvectors = 3;

    else

        n->vdev.nvectors = dev->nd->nvectors;



    register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,

                    virtio_net_save, virtio_net_load, n);

net.c

+17 −1
Original line number Diff line number Diff line
@@ -2169,7 +2169,7 @@ int net_client_init(Monitor *mon, const char *device, const char *p) 
    }

    if (!strcmp(device, "nic")) {

        static const char * const nic_params[] = {

            "vlan", "name", "macaddr", "model", "addr", NULL

            "vlan", "name", "macaddr", "model", "addr", "vectors", NULL

        };

        NICInfo *nd;

        uint8_t *macaddr;
@@ -2207,6 +2207,22 @@ int net_client_init(Monitor *mon, const char *device, const char *p) 
        if (get_param_value(buf, sizeof(buf), "addr", p)) {

            nd->devaddr = strdup(buf);

        }

        nd->nvectors = NIC_NVECTORS_UNSPECIFIED;

        if (get_param_value(buf, sizeof(buf), "vectors", p)) {

            char *endptr;

            long vectors = strtol(buf, &endptr, 0);

            if (*endptr) {

                config_error(mon, "invalid syntax for # of vectors\n");

                ret = -1;

                goto out;

            }

            if (vectors < 0 || vectors > 0x7ffffff) {

                config_error(mon, "invalid # of vectors\n");

                ret = -1;

                goto out;

            }

            nd->nvectors = vectors;

        }

        nd->vlan = vlan;

        nd->name = name;

        nd->used = 1;

net.h

+4 −0
Original line number Diff line number Diff line
@@ -84,6 +84,9 @@ int do_set_link(Monitor *mon, const char *name, const char *up_or_down); 
/* NIC info */



#define MAX_NICS 8

enum {

	NIC_NVECTORS_UNSPECIFIED = -1

};



struct NICInfo {

    uint8_t macaddr[6];
@@ -94,6 +97,7 @@ struct NICInfo { 
    void *private;

    int used;

    int bootable;

    int nvectors;

};



extern int nb_nics;

qemu-options.hx

+8 −6
Original line number Diff line number Diff line
@@ -736,7 +736,7 @@ STEXI 
ETEXI



DEF("net", HAS_ARG, QEMU_OPTION_net,

    "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str]\n"

    "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"

    "                create a new Network Interface Card and connect it to VLAN 'n'\n"

#ifdef CONFIG_SLIRP

    "-net user[,vlan=n][,name=str][,hostname=host]\n"
@@ -777,16 +777,18 @@ DEF("net", HAS_ARG, QEMU_OPTION_net, 
    "-net none       use it alone to have zero network devices; if no -net option\n"

    "                is provided, the default is '-net nic -net user'\n")

STEXI

@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}][,name=@var{name}][,addr=@var{addr}]

@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}][,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]

Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}

= 0 is the default). The NIC is an ne2k_pci by default on the PC

target. Optionally, the MAC address can be changed to @var{mac}, the

device address set to @var{addr} (PCI cards only),

and a @var{name} can be assigned for use in monitor commands. If no

@option{-net} option is specified, a single NIC is created.

Qemu can emulate several different models of network card.

and a @var{name} can be assigned for use in monitor commands.

Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors

that the card should have; this option currently only affects virtio cards; set

@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single

NIC is created.  Qemu can emulate several different models of network card.

Valid values for @var{type} are

@code{i82551}, @code{i82557b}, @code{i82559er},

@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},

@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},

@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.

Not all devices are supported on all targets.  Use -net nic,model=?