Re: [dpdk-dev] [PATCH 2/2] net/mlx5: add fine grain dynamic flag support

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/16/2020 12:05 PM, Ori Kam wrote:
> Hi Ferruh,
> 
>> -----Original Message-----
>> From: Ferruh Yigit <ferruh.yigit@intel.com>
>> Sent: Wednesday, January 15, 2020 4:02 PM
>> To: Ori Kam <orika@mellanox.com>; Matan Azrad <matan@mellanox.com>;
>> Shahaf Shuler <shahafs@mellanox.com>; Slava Ovsiienko
>> <viacheslavo@mellanox.com>
>> Cc: dev@dpdk.org
>> Subject: Re: [PATCH 2/2] net/mlx5: add fine grain dynamic flag support
>>
>> On 1/13/2020 9:29 AM, Ori Kam wrote:
>>> The inline feature is designed to save PCI bandwidth by copying some
>>> of the data to the wqe. This feature if enabled works for all packets.
>>>
>>> In some cases when using external memory, the PCI bandwidth is not
>>> relevant since the memory can be accessed by other means.
>>>
>>> This commit introduce the ability to control the inline with mbuf
>>> granularity.
>>>
>>> In order to use this feature the application should register the field
>>> name, and restart the port.
>>>
>>> Signed-off-by: Ori Kam <orika@mellanox.com>
>>> Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
>>> ---
>>>  drivers/net/mlx5/mlx5.c                   | 15 +++++++++++++++
>>>  drivers/net/mlx5/mlx5_rxtx.c              |  2 ++
>>>  drivers/net/mlx5/mlx5_rxtx.h              |  3 +++
>>>  drivers/net/mlx5/mlx5_trigger.c           |  8 ++++++++
>>>  drivers/net/mlx5/rte_pmd_mlx5.h           | 32
>> +++++++++++++++++++++++++++++++
>>>  drivers/net/mlx5/rte_pmd_mlx5_version.map |  7 +++++++
>>>  6 files changed, 67 insertions(+)
>>>  create mode 100644 drivers/net/mlx5/rte_pmd_mlx5.h
>>>
>>> diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
>>> index 50960c9..27dbe27 100644
>>> --- a/drivers/net/mlx5/mlx5.c
>>> +++ b/drivers/net/mlx5/mlx5.c
>>> @@ -46,6 +46,7 @@
>>>  #include "mlx5_glue.h"
>>>  #include "mlx5_mr.h"
>>>  #include "mlx5_flow.h"
>>> +#include "rte_pmd_mlx5.h"
>>>
>>>  /* Device parameter to enable RX completion queue compression. */
>>>  #define MLX5_RXQ_CQE_COMP_EN "rxq_cqe_comp_en"
>>> @@ -1988,6 +1989,20 @@ struct mlx5_flow_id_pool *
>>>  	return ret;
>>>  }
>>>
>>> +int
>>> +rte_pmd_mlx5_get_dyn_flag_names(char *names[], uint16_t n)
>>> +{
>>
>> Now this is a public API, it should validate the user input.
>>
> Will add validation to make sure names != NULL,
> 
>>> +	static const char *const dynf_names[] = {
>>> +		RTE_PMD_MLX5_FINE_GRANULARITY_INLINE,
>>> +	};
>>> +	int num = RTE_MIN(n, RTE_DIM(dynf_names));
>>> +	int i;
>>> +
>>> +	for (i = 0; i < num; i++)
>>> +		strcpy(names[i], dynf_names[i]);
>>> +	return num;
>>> +}
>>> +
>>>  /**
>>>   * Check sibling device configurations.
>>>   *
>>> diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
>>> index 67cafd1..aa6aa22 100644
>>> --- a/drivers/net/mlx5/mlx5_rxtx.c
>>> +++ b/drivers/net/mlx5/mlx5_rxtx.c
>>> @@ -126,6 +126,8 @@ enum mlx5_txcmp_code {
>>>  uint8_t mlx5_cksum_table[1 << 10] __rte_cache_aligned;
>>>  uint8_t mlx5_swp_types_table[1 << 10] __rte_cache_aligned;
>>>
>>> +uint64_t rte_net_mlx5_dynf_inline_mask;
>>> +
>>>  /**
>>>   * Build a table to translate Rx completion flags to packet type.
>>>   *
>>> diff --git a/drivers/net/mlx5/mlx5_rxtx.h b/drivers/net/mlx5/mlx5_rxtx.h
>>> index e362b4a..7c38c57 100644
>>> --- a/drivers/net/mlx5/mlx5_rxtx.h
>>> +++ b/drivers/net/mlx5/mlx5_rxtx.h
>>> @@ -42,6 +42,9 @@
>>>  /* Support tunnel matching. */
>>>  #define MLX5_FLOW_TUNNEL 9
>>>
>>> +/* Mbuf dynamic flag offset for inline. */
>>> +extern uint64_t rte_net_mlx5_dynf_inline_mask;
>>> +
>>>  struct mlx5_rxq_stats {
>>>  #ifdef MLX5_PMD_SOFT_COUNTERS
>>>  	uint64_t ipackets; /**< Total of successfully received packets. */
>>> diff --git a/drivers/net/mlx5/mlx5_trigger.c
>> b/drivers/net/mlx5/mlx5_trigger.c
>>> index ab6937a..ab253b2 100644
>>> --- a/drivers/net/mlx5/mlx5_trigger.c
>>> +++ b/drivers/net/mlx5/mlx5_trigger.c
>>> @@ -13,6 +13,7 @@
>>>  #include "mlx5.h"
>>>  #include "mlx5_rxtx.h"
>>>  #include "mlx5_utils.h"
>>> +#include "rte_pmd_mlx5.h"
>>>
>>>  /**
>>>   * Stop traffic on Tx queues.
>>> @@ -270,8 +271,15 @@
>>>  {
>>>  	struct mlx5_priv *priv = dev->data->dev_private;
>>>  	int ret;
>>> +	int fine_inline;
>>>
>>>  	DRV_LOG(DEBUG, "port %u starting device", dev->data->port_id);
>>> +	fine_inline = rte_mbuf_dynflag_lookup
>>> +		(RTE_PMD_MLX5_FINE_GRANULARITY_INLINE, NULL);
>>> +	if (fine_inline > 0)
>>> +		rte_net_mlx5_dynf_inline_mask = 1UL << fine_inline;
>>> +	else
>>> +		rte_net_mlx5_dynf_inline_mask = 0;
>>>  	ret = mlx5_dev_configure_rss_reta(dev);
>>>  	if (ret) {
>>>  		DRV_LOG(ERR, "port %u reta config failed: %s",
>>> diff --git a/drivers/net/mlx5/rte_pmd_mlx5.h
>> b/drivers/net/mlx5/rte_pmd_mlx5.h
>>> new file mode 100644
>>> index 0000000..12e18ca
>>> --- /dev/null
>>> +++ b/drivers/net/mlx5/rte_pmd_mlx5.h
>>> @@ -0,0 +1,32 @@
>>> +/* SPDX-License-Identifier: BSD-3-Clause
>>> + * Copyright 2020 Mellanox Technologies, Ltd
>>> + */
>>> +
>>> +#ifndef RTE_PMD_PRIVATE_MLX5_H_
>>> +#define RTE_PMD_PRIVATE_MLX5_H_
>>> +
>>> +/**
>>> + * @file
>>> + * MLX5 public header.
>>> + *
>>> + * This interface provides the ability to support private PMD
>>> + * dynamic flags.
>>> + */
>>> +
>>> +#define RTE_PMD_MLX5_FINE_GRANULARITY_INLINE
>> "mlx5_fine_granularity_inline"
>>> +
>>> +/**
>>> + * Returns the dynamic flags name, that are supported.
>>> + *
>>> + * @param[out] names
>>> + *   Array that is used to return the supported dynamic flags names.
>>> + * @param[in] n
>>> + *   The number of elements in the names array.
>>> + *
>>> + * @return
>>> + *   The number of dynamic flags that were copied.
>>> + */
>>> +__rte_experimental
>>> +int rte_pmd_mlx5_get_dyn_flag_names(char *names[], uint16_t n);
>>
>> Can you please add this header to the API documentation index,
>> doc/api/doxy-api-index.md, so it will be part of API document.
>>
> 
> Will add.
> 
>>> +
>>> +#endif
>>> diff --git a/drivers/net/mlx5/rte_pmd_mlx5_version.map
>> b/drivers/net/mlx5/rte_pmd_mlx5_version.map
>>> index f9f17e4..c8b1031 100644
>>> --- a/drivers/net/mlx5/rte_pmd_mlx5_version.map
>>> +++ b/drivers/net/mlx5/rte_pmd_mlx5_version.map
>>> @@ -1,3 +1,10 @@
>>>  DPDK_20.0 {
>>>  	local: *;
>>>  };
>>> +
>>> +EXPERIMENTAL {
>>> +        global:
>>> +
>>> +        # added in 20.02
>>> +	rte_pmd_mlx5_get_dyn_flag_names;
>>> +};
>>>
>>
>> Isn't the datapath implementation missing? Where this new mbuf dynamic
>> flag set
>> or checked?
> 
> The data path implementation will be done in different patch.
> The flags is set for example using the testpmd new API or by the application.
> The reason that I added this patch is to show usage for the testpmd patch, I can remove this patch and 
> re send it when sending the datapath patch.
> What do you think?
> 

I think testpmd patch is clear enough on its own and better to send PMD patch
separately when it is complete.