Re: [Qemu-devel] [PATCH COLO-Frame v13 34/39] net/filter-buffer: Add default filter-buffer for each netdev

[Hailiang Zhang <zhang.zhanghailiang@huawei.com>]

ping?

The other part of this series have been fully reviewed except this net related part.
We hope COLO frame could be merged in qemu 2.6, so please help us.
Any comments will be welcomed, thanks.

zhanghailiang

On 2016/1/11 9:26, Hailiang Zhang wrote:
> Hi Jason,
>
> Could you please help reviewing the filter part of this series ?
>
> Thanks,
> Hailiang
>
> On 2015/12/29 15:09, zhanghailiang wrote:
>> We add each netdev (except vhost-net) a default filter-buffer,
>> which will be used for COLO or Micro-checkpoint to buffer VM's packets.
>> The name of default filter-buffer is 'nop'.
>> For the default filter-buffer, it will not buffer any packets in default.
>> So it has no side effect for the netdev.
>>
>> Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
>> Cc: Jason Wang <jasowang@redhat.com>
>> Cc: Yang Hongyang <hongyang.yang@easystack.cn>
>> ---
>> v12:
>> - Skip vhost-net when add default filter
>> - Don't go through filter layer if the filter is disabled.
>> v11:
>> - New patch
>> ---
>>   include/net/filter.h | 10 +++++++
>>   net/filter-buffer.c  | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   net/filter.c         |  6 +++-
>>   net/net.c            | 12 ++++++++
>>   4 files changed, 109 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/net/filter.h b/include/net/filter.h
>> index 2deda36..40aa38c 100644
>> --- a/include/net/filter.h
>> +++ b/include/net/filter.h
>> @@ -56,6 +56,8 @@ struct NetFilterState {
>>       NetClientState *netdev;
>>       NetFilterDirection direction;
>>       char info_str[256];
>> +    bool is_default;
>> +    bool enabled;
>>       QTAILQ_ENTRY(NetFilterState) next;
>>   };
>>
>> @@ -74,4 +76,12 @@ ssize_t qemu_netfilter_pass_to_next(NetClientState *sender,
>>                                       int iovcnt,
>>                                       void *opaque);
>>
>> +static inline bool qemu_need_skip_netfilter(NetFilterState *nf)
>> +{
>> +    return nf->enabled ? false : true;
>> +}
>> +
>> +void netdev_add_default_filter_buffer(const char *netdev_id,
>> +                                      NetFilterDirection direction,
>> +                                      Error **errp);
>>   #endif /* QEMU_NET_FILTER_H */
>> diff --git a/net/filter-buffer.c b/net/filter-buffer.c
>> index 57be149..9cf3544 100644
>> --- a/net/filter-buffer.c
>> +++ b/net/filter-buffer.c
>> @@ -14,6 +14,13 @@
>>   #include "qapi/qmp/qerror.h"
>>   #include "qapi-visit.h"
>>   #include "qom/object.h"
>> +#include "net/net.h"
>> +#include "qapi/qmp/qdict.h"
>> +#include "qapi/qmp-output-visitor.h"
>> +#include "qapi/qmp-input-visitor.h"
>> +#include "monitor/monitor.h"
>> +#include "qmp-commands.h"
>> +#include "net/vhost_net.h"
>>
>>   #define TYPE_FILTER_BUFFER "filter-buffer"
>>
>> @@ -102,6 +109,7 @@ static void filter_buffer_cleanup(NetFilterState *nf)
>>   static void filter_buffer_setup(NetFilterState *nf, Error **errp)
>>   {
>>       FilterBufferState *s = FILTER_BUFFER(nf);
>> +    char *path = object_get_canonical_path_component(OBJECT(nf));
>>
>>       /*
>>        * We may want to accept zero interval when VM FT solutions like MC
>> @@ -114,6 +122,14 @@ static void filter_buffer_setup(NetFilterState *nf, Error **errp)
>>       }
>>
>>       s->incoming_queue = qemu_new_net_queue(qemu_netfilter_pass_to_next, nf);
>> +    nf->is_default = !strcmp(path, "nop");
>> +    /*
>> +    * For the default buffer filter, it will be disabled by default,
>> +    * So it will not buffer any packets.
>> +    */
>> +    if (nf->is_default) {
>> +        nf->enabled = false;
>> +    }
>>       if (s->interval) {
>>           timer_init_us(&s->release_timer, QEMU_CLOCK_VIRTUAL,
>>                         filter_buffer_release_timer, nf);
>> @@ -163,6 +179,72 @@ out:
>>       error_propagate(errp, local_err);
>>   }
>>
>> +/*
>> +* This will be used by COLO or MC FT, for which they will need
>> +* to buffer the packets of VM's net devices, Here we add a default
>> +* buffer filter for each netdev. The name of default buffer filter is
>> +* 'nop'
>> +*/
>> +void netdev_add_default_filter_buffer(const char *netdev_id,
>> +                                      NetFilterDirection direction,
>> +                                      Error **errp)
>> +{
>> +    QmpOutputVisitor *qov;
>> +    QmpInputVisitor *qiv;
>> +    Visitor *ov, *iv;
>> +    QObject *obj = NULL;
>> +    QDict *qdict;
>> +    void *dummy = NULL;
>> +    const char *id = "nop";
>> +    char *queue = g_strdup(NetFilterDirection_lookup[direction]);
>> +    NetClientState *nc = qemu_find_netdev(netdev_id);
>> +    Error *err = NULL;
>> +
>> +    /* FIXME: Not support multiple queues */
>> +    if (!nc || nc->queue_index > 1) {
>> +        g_free(queue);
>> +        return;
>> +    }
>> +    /* Not support vhost-net */
>> +    if (get_vhost_net(nc)) {
>> +        g_free(queue);
>> +        return;
>> +    }
>> +    qov = qmp_output_visitor_new();
>> +    ov = qmp_output_get_visitor(qov);
>> +    visit_start_struct(ov,  &dummy, NULL, NULL, 0, &err);
>> +    if (err) {
>> +        goto out;
>> +    }
>> +    visit_type_str(ov, &nc->name, "netdev", &err);
>> +    if (err) {
>> +        goto out;
>> +    }
>> +    visit_type_str(ov, &queue, "queue", &err);
>> +    if (err) {
>> +        goto out;
>> +    }
>> +    visit_end_struct(ov, &err);
>> +    if (err) {
>> +        goto out;
>> +    }
>> +    obj = qmp_output_get_qobject(qov);
>> +    g_assert(obj != NULL);
>> +    qdict = qobject_to_qdict(obj);
>> +    qmp_output_visitor_cleanup(qov);
>> +
>> +    qiv = qmp_input_visitor_new(obj);
>> +    iv = qmp_input_get_visitor(qiv);
>> +    object_add(TYPE_FILTER_BUFFER, id, qdict, iv, &err);
>> +    qmp_input_visitor_cleanup(qiv);
>> +    qobject_decref(obj);
>> +out:
>> +    g_free(queue);
>> +    if (err) {
>> +        error_propagate(errp, err);
>> +    }
>> +}
>> +
>>   static void filter_buffer_init(Object *obj)
>>   {
>>       object_property_add(obj, "interval", "int",
>> diff --git a/net/filter.c b/net/filter.c
>> index 1365bad..0b1e408 100644
>> --- a/net/filter.c
>> +++ b/net/filter.c
>> @@ -163,7 +163,8 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
>>       }
>>
>>       nf->netdev = ncs[0];
>> -
>> +    nf->is_default = false;
>> +    nf->enabled = true;
>>       if (nfc->setup) {
>>           nfc->setup(nf, &local_err);
>>           if (local_err) {
>> @@ -190,6 +191,9 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
>>           g_free(info);
>>       }
>>       object_property_iter_free(iter);
>> +    info = g_strdup_printf(",status=%s", nf->enabled ? "on" : "off");
>> +    g_strlcat(nf->info_str, info, sizeof(nf->info_str));
>> +    g_free(info);
>>   }
>>
>>   static void netfilter_finalize(Object *obj)
>> diff --git a/net/net.c b/net/net.c
>> index 87dd356..fd53cfc 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -581,6 +581,10 @@ static ssize_t filter_receive_iov(NetClientState *nc,
>>       NetFilterState *nf = NULL;
>>
>>       QTAILQ_FOREACH(nf, &nc->filters, next) {
>> +        /* Don't go through filter if it is off */
>> +        if (qemu_need_skip_netfilter(nf)) {
>> +            continue;
>> +        }
>>           ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
>>                                        iovcnt, sent_cb);
>>           if (ret) {
>> @@ -1028,6 +1032,14 @@ static int net_client_init1(const void *object, int is_netdev, Error **errp)
>>           }
>>           return -1;
>>       }
>> +
>> +    if (is_netdev) {
>> +        const Netdev *netdev = object;
>> +
>> +        netdev_add_default_filter_buffer(netdev->id,
>> +                                         NET_FILTER_DIRECTION_RX,
>> +                                         errp);
>> +    }
>>       return 0;
>>   }
>>
>>
>