On Sat, Dec 4, 2021 at 11:08 PM Stephen Hemminger
<step...@networkplumber.org> wrote:
>
> On Sat, 4 Dec 2021 22:54:58 +0530
> <jer...@marvell.com> wrote:
>
> > + /**
> > + * Maximum supported traffic class as per PFC (802.1Qbb)
> > specification.
> > + *
> > + * Based on device support and use-case need, there are two different
> > + * ways to enable PFC. The first case is the port level PFC
> > + * configuration, in this case, rte_eth_dev_priority_flow_ctrl_set()
> > + * API shall be used to configure the PFC, and PFC frames will be
> > + * generated using based on VLAN TC value.
> > + * The second case is the queue level PFC configuration, in this case,
> > + * Any packet field content can be used to steer the packet to the
> > + * specific queue using rte_flow or RSS and then use
> > + * rte_eth_dev_priority_flow_ctrl_queue_set() to set the TC mapping
> > + * on each queue. Based on congestion selected on the specific queue,
> > + * configured TC shall be used to generate PFC frames.
> > + *
> > + * When set to non zero value, application must use queue level
> > + * PFC configuration via rte_eth_dev_priority_flow_ctrl_queue_set()
> > API
> > + * instead of port level PFC configuration via
> > + * rte_eth_dev_priority_flow_ctrl_set() API to realize
> > + * PFC configuration.
> > + */
> > + uint8_t pfc_queue_tc_max;
> > + uint8_t reserved_8s[7];
> > + uint64_t reserved_64s[1]; /**< Reserved for future fields */
> > void *reserved_ptrs[2]; /**< Reserved for future fields */
>
> Not sure you can claim ABI compatibility because the previous versions of DPDK
> did not enforce that reserved fields must be zero. The Linux kernel
> learned this when adding flags for new system calls; reserved fields only
> work if you enforce that application must set them to zero.
In this case it rte_eth_dev_info is an out parameter and implementation of
rte_eth_dev_info_get() already memseting to 0.
Do you still see any other ABI issue?
See rte_eth_dev_info_get()
/*
* Init dev_info before port_id check since caller does not have
* return status and does not know if get is successful or not.
*/
memset(dev_info, 0, sizeof(struct rte_eth_dev_info));
