On 2021/9/18 0:41, Kevin Laatz wrote:
> The dmadev library abstraction allows applications to use the same APIs for
> all DMA device drivers in DPDK. This patch updates the ioatfwd application
> to make use of the new dmadev APIs, in turn making it a generic application
> which can be used with any of the DMA device drivers.
>
> Signed-off-by: Kevin Laatz <kevin.la...@intel.com>
>
> ---
> v2:
> - dmadev api name updates following rebase
> - use rte_config macro for max devs
> - use PRIu64 for printing stats
> ---
> examples/ioat/ioatfwd.c | 239 ++++++++++++++++----------------------
> examples/ioat/meson.build | 8 +-
> 2 files changed, 105 insertions(+), 142 deletions(-)
>
[snip]
>
> typedef enum copy_mode_t {
> @@ -95,6 +94,16 @@ static copy_mode_t copy_mode = COPY_MODE_IOAT_NUM;
> */
> static unsigned short ring_size = 2048;
>
> +/* global mbuf arrays for tracking DMA bufs */
> +#define MBUF_RING_SIZE 1024
> +#define MBUF_RING_MASK (MBUF_RING_SIZE - 1)
> +struct dma_bufs {
> + struct rte_mbuf *bufs[MBUF_RING_SIZE];
> + struct rte_mbuf *copies[MBUF_RING_SIZE];
> + uint16_t sent;
> +};
The dma_bufs size only hold 1024 address info, and the dmadev virtual channel
ring size is 2048 default,
If the DMA cannot be moved in time, may exist overlay in dma_bufs in
dma_dequeue() API.
> +static struct dma_bufs dma_bufs[RTE_DMADEV_DEFAULT_MAX_DEVS];
> +
> /* global transmission config */
> struct rxtx_transmission_config cfg;
[snip]
> }
> /* >8 End of configuration of device. */
>
> @@ -820,18 +789,16 @@ assign_rawdevs(void)
>
> for (i = 0; i < cfg.nb_ports; i++) {
> for (j = 0; j < cfg.ports[i].nb_queues; j++) {
> - struct rte_rawdev_info rdev_info = { 0 };
> + struct rte_dma_info dmadev_info = { 0 };
>
> do {
> - if (rdev_id == rte_rawdev_count())
> + if (rdev_id == rte_dma_count_avail())
> goto end;
> - rte_rawdev_info_get(rdev_id++, &rdev_info, 0);
> - } while (rdev_info.driver_name == NULL ||
> - strcmp(rdev_info.driver_name,
> - IOAT_PMD_RAWDEV_NAME_STR) != 0);
> + rte_dma_info_get(rdev_id++, &dmadev_info);
> + } while (!rte_dma_is_valid(rdev_id));
>
> - cfg.ports[i].ioat_ids[j] = rdev_id - 1;
> - configure_rawdev_queue(cfg.ports[i].ioat_ids[j]);
> + cfg.ports[i].dmadev_ids[j] = rdev_id - 1;
> + configure_rawdev_queue(cfg.ports[i].dmadev_ids[j]);
Tests show that if there are four dmadevs, only three dmadevs can be allocated
here.
1st malloc: rdev_id=0, assign successful, and the dmadev_id=0, rdev_id=1
2st malloc: rdev_id=1, assign successful, and the dmadev_id=1, rdev_id=2
3st malloc: rdev_id=2, assign successful, and the dmadev_id=2, rdev_id=3
4st malloc: rdev_id=3, assign failed, because rte_dma_info_get(rdev_id++,...),
the rdev_id is 4 and it's not a valid id.
Recommended use rte_dma_next_dev() which Bruce introduced.
> ++nb_rawdev;
> }
> }
> @@ -840,7 +807,7 @@ assign_rawdevs(void)
> rte_exit(EXIT_FAILURE,
> "Not enough IOAT rawdevs (%u) for all queues (%u).\n",
> nb_rawdev, cfg.nb_ports * cfg.ports[0].nb_queues);
> - RTE_LOG(INFO, IOAT, "Number of used rawdevs: %u.\n", nb_rawdev);
> + RTE_LOG(INFO, DMA, "Number of used rawdevs: %u.\n", nb_rawdev);
> }
> /* >8 End of using IOAT rawdev API functions. */
>
[snip]
