On 21 Oct 2021, at 10:00, Chris Mi wrote:

> Some offload actions require functionality that is not netdev
> based, but dpif. For example, sFlow action requires to create
> a psample netlink socket to receive the sampled packets from
> TC or kernel driver.
>
> Create dpif-offload-provider layer to support such actions.
>
> Signed-off-by: Chris Mi <[email protected]>
> Reviewed-by: Eli Britstein <[email protected]>
> ---
>  lib/automake.mk             |  2 ++
>  lib/dpif-offload-provider.h | 40 ++++++++++++++++++++++++++++++++++
>  lib/dpif-offload.c          | 43 +++++++++++++++++++++++++++++++++++++
>  lib/dpif-provider.h         |  4 +++-
>  4 files changed, 88 insertions(+), 1 deletion(-)
>  create mode 100644 lib/dpif-offload-provider.h
>  create mode 100644 lib/dpif-offload.c
>
> diff --git a/lib/automake.mk b/lib/automake.mk
> index 46f869a33..9259f57de 100644
> --- a/lib/automake.mk
> +++ b/lib/automake.mk
> @@ -127,6 +127,8 @@ lib_libopenvswitch_la_SOURCES = \
>       lib/dpif-netdev-private.h \
>       lib/dpif-netdev-perf.c \
>       lib/dpif-netdev-perf.h \
> +     lib/dpif-offload.c \
> +     lib/dpif-offload-provider.h \
>       lib/dpif-provider.h \
>       lib/dpif.c \
>       lib/dpif.h \
> diff --git a/lib/dpif-offload-provider.h b/lib/dpif-offload-provider.h
> new file mode 100644
> index 000000000..b5eb4ab04
> --- /dev/null
> +++ b/lib/dpif-offload-provider.h
> @@ -0,0 +1,40 @@
> +/*
> + * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
> + *
> + * Licensed under the Apache License, Version 2.0 (the "License");
> + * you may not use this file except in compliance with the License.
> + * You may obtain a copy of the License at:
> + *
> + *     http://www.apache.org/licenses/LICENSE-2.0
> + *
> + * Unless required by applicable law or agreed to in writing, software
> + * distributed under the License is distributed on an "AS IS" BASIS,
> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
> + * See the License for the specific language governing permissions and
> + * limitations under the License.
> + */
> +
> +#ifndef DPIF_OFFLOAD_PROVIDER_H
> +#define DPIF_OFFLOAD_PROVIDER_H
> +
> +struct dpif;
> +struct dpif_offload_sflow;
> +
> +/* Datapath interface offload structure, to be defined by each implementation
> + * of a datapath interface.
> + */
> +struct dpif_offload_api {
> +    /* Arranges for the poll loop for an upcall handler to wake up when 
> psample
> +     * has a message queued to be received. */
> +    void (*sflow_recv_wait)(void);
> +
> +    /* Polls for an upcall from psample for an upcall handler.
> +     * Return 0 for success. */
> +    int (*sflow_recv)(struct dpif_offload_sflow *sflow);
> +};
>

Not sure why you removed the init and destroy functions, as the offload API 
should be like a class (where multiple could exist), and init/destroy should be 
called when you register the offload class.
Guess more comments will be in patch 5.

> +void dpif_offload_sflow_recv_wait(const struct dpif *dpif);
> +int dpif_offload_sflow_recv(const struct dpif *dpif,
> +                            struct dpif_offload_sflow *sflow);
> +
> +#endif /* DPIF_OFFLOAD_PROVIDER_H */
> diff --git a/lib/dpif-offload.c b/lib/dpif-offload.c
> new file mode 100644
> index 000000000..44e79882f
> --- /dev/null
> +++ b/lib/dpif-offload.c
> @@ -0,0 +1,43 @@
> +/*
> + * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
> + *
> + * Licensed under the Apache License, Version 2.0 (the "License");
> + * you may not use this file except in compliance with the License.
> + * You may obtain a copy of the License at:
> + *
> + *     http://www.apache.org/licenses/LICENSE-2.0
> + *
> + * Unless required by applicable law or agreed to in writing, software
> + * distributed under the License is distributed on an "AS IS" BASIS,
> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
> + * See the License for the specific language governing permissions and
> + * limitations under the License.
> + */
> +
> +#include <config.h>
> +#include <errno.h>
> +
> +#include "dpif-provider.h"
> +
> +void
> +dpif_offload_sflow_recv_wait(const struct dpif *dpif)
> +{
> +    const struct dpif_offload_api *offload_api = dpif->offload_api;
> +
> +    if (offload_api && offload_api->sflow_recv_wait) {
> +        offload_api->sflow_recv_wait();
> +    }
> +}
> +
> +int
> +dpif_offload_sflow_recv(const struct dpif *dpif,
> +                        struct dpif_offload_sflow *sflow)
> +{
> +    const struct dpif_offload_api *offload_api = dpif->offload_api;
> +
> +    if (offload_api && offload_api->sflow_recv) {
> +        return offload_api->sflow_recv(sflow);
> +    }
> +
> +    return EOPNOTSUPP;
> +}
> diff --git a/lib/dpif-provider.h b/lib/dpif-provider.h
> index 7e11b9697..15a0d2b63 100644
> --- a/lib/dpif-provider.h
> +++ b/lib/dpif-provider.h
> @@ -22,8 +22,9 @@
>   * exposed over OpenFlow as a single switch.  Datapaths and the collections 
> of
>   * ports that they contain may be fixed or dynamic. */
>
> -#include "openflow/openflow.h"
>  #include "dpif.h"
> +#include "dpif-offload-provider.h"
> +#include "openflow/openflow.h"
>  #include "util.h"
>
>  #ifdef  __cplusplus
> @@ -35,6 +36,7 @@ extern "C" {
>   * This structure should be treated as opaque by dpif implementations. */
>  struct dpif {
>      const struct dpif_class *dpif_class;
> +    const struct dpif_offload_api *offload_api;
>      char *base_name;
>      char *full_name;
>      uint8_t netflow_engine_type;
> -- 
> 2.30.2

Adding the previous conversation about the API in general, so Ilya or who ever 
reviews this can follow up:


EC> Here you add the provider directly into the dpif class. Not sure if this is 
what Ilya had in mind. As in general, these get integrated into the 
dpif/netdev, not the class. Ilya can you comment on/review this?
CM> OK.

EC> To me, it's also not clear how we would continue from here, are there any 
plans to move all offload stuff to the offload provider? If so, in what time 
frame?

CM> I assume this question is for Ilya. If it is for me, I don't have the 
answer now. 😅
CM> Maybe we can open another thread to discuss it.

EC> Guess it’s for both you and Ilya. In some of the conversations with the 
CCed people, this new offload provider was discussed, and I remember it was 
mentioned that it only makes sense if there was a plan to follow through with 
the migration.

EC> I’m afraid if we add the framework in this patch and it will not be 
followed up, it will cause confusion in the future.

CM> OK, I see. We'll also discuss the plan internally.

====

CM> The main idea of dpif-offload layer is for some offload actions that are 
not netdev based, but dpif based, like sFlow. And metering is another example 
that can leverage on it.
CM> All other offload stuff can be moved to dpif-offload layer. But that's not 
the main aim for dpif-offload.
CM> I think the plan is out of scope of this patchset.

_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev

Reply via email to