Re: [Qemu-devel] [PATCH 11/12] filter/buffer: add an interval option to buffer filter

[Jason Wang <jasowang@redhat.com>]

On 07/29/2015 06:51 PM, Yang Hongyang wrote:
> the buffer filter will release packets by interval.
>
> Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>

Looks liked it's better to squash this patch into the buffer? And should
we stop the timer during vm stop?

> ---
>  net/filter-buffer.c | 24 ++++++++++++++++++++++++
>  qapi-schema.json    |  7 ++++++-
>  2 files changed, 30 insertions(+), 1 deletion(-)
>
> diff --git a/net/filter-buffer.c b/net/filter-buffer.c
> index 8bac73b..902d9f7 100644
> --- a/net/filter-buffer.c
> +++ b/net/filter-buffer.c
> @@ -12,6 +12,7 @@
>  #include "qemu-common.h"
>  #include "qemu/error-report.h"
>  #include "qemu/main-loop.h"
> +#include "qemu/timer.h"
>  
>  typedef struct FILTERBUFFERState {
>      NetFilterState nf;
> @@ -19,6 +20,8 @@ typedef struct FILTERBUFFERState {
>      NetQueue *incoming_queue;
>      NetQueue *inflight_queue;
>      QEMUBH *flush_bh;
> +    int64_t interval;
> +    QEMUTimer release_timer;
>  } FILTERBUFFERState;
>  
>  static void packet_send_completed(NetClientState *nc, ssize_t len)
> @@ -79,6 +82,14 @@ static void filter_buffer_release_one(NetFilterState *nf)
>      qemu_bh_schedule(s->flush_bh);
>  }
>  
> +static void filter_buffer_release_timer(void *opaque)
> +{
> +    FILTERBUFFERState *s = opaque;
> +    filter_buffer_release_one(&s->nf);
> +    timer_mod(&s->release_timer,
> +              qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
> +}
> +
>  /* filter APIs */
>  static ssize_t filter_buffer_receive(NetFilterState *nf,
>                                       NetClientState *sender,
> @@ -109,6 +120,10 @@ static void filter_buffer_cleanup(NetFilterState *nf)
>  {
>      FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf);
>  
> +    if (s->interval) {
> +        timer_del(&s->release_timer);
> +    }
> +
>      /* flush inflight packets */
>      filter_buffer_flush(nf);
>      /* flush incoming packets */
> @@ -136,8 +151,10 @@ int net_init_filter_buffer(const NetFilterOptions *opts, const char *name,
>  {
>      NetFilterState *nf;
>      FILTERBUFFERState *s;
> +    const NetFilterBufferOptions *bufferopt;
>  
>      assert(opts->kind == NET_FILTER_OPTIONS_KIND_BUFFER);
> +    bufferopt = opts->buffer;
>  
>      nf = qemu_new_net_filter(&net_filter_buffer_info, netdev, "buffer", name);
>      s = DO_UPCAST(FILTERBUFFERState, nf, nf);
> @@ -150,6 +167,13 @@ int net_init_filter_buffer(const NetFilterOptions *opts, const char *name,
>      s->dummy.peer = netdev;
>      s->incoming_queue = qemu_new_net_queue(nf);
>      s->flush_bh = qemu_bh_new(filter_buffer_flush_bh, s);
> +    s->interval = bufferopt->has_interval ? bufferopt->interval : 0;
> +    if (s->interval) {
> +        timer_init_us(&s->release_timer, QEMU_CLOCK_VIRTUAL,
> +                      filter_buffer_release_timer, s);
> +        timer_mod(&s->release_timer,
> +                  qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
> +    }
>  
>      return 0;
>  }
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 67e00a0..45b357d 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -2581,10 +2581,15 @@
>  #
>  # a netbuffer filter for network backend.
>  #
> +# @interval: #optional release packets by interval, if no interval supplied,
> +#            will release packets when filter_buffer_release_all been called.
> +#            scale: microsecond
> +#
>  # Since 2.5
>  ##
>  { 'struct': 'NetFilterBufferOptions',
> -  'data': { } }
> +  'data': {
> +    '*interval':     'int64' } }
>  
>  ##
>  # @NetFilterOptions