[dpdk-dev,2/8] net/mlx4: remove unnecessary Tx wraparound checks
Checks
Commit Message
There is no need to check Tx queue wraparound for segments which are
not at the beginning of a Tx block. Especially relevant in a single
segment case.
Remove unnecessary aforementioned checks from Tx path.
Signed-off-by: Matan Azrad <matan@mellanox.com>
---
drivers/net/mlx4/mlx4_rxtx.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
Comments
On Tue, Nov 28, 2017 at 12:19:24PM +0000, Matan Azrad wrote:
> There is no need to check Tx queue wraparound for segments which are
> not at the beginning of a Tx block. Especially relevant in a single
> segment case.
>
> Remove unnecessary aforementioned checks from Tx path.
>
> Signed-off-by: Matan Azrad <matan@mellanox.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
@@ -461,15 +461,11 @@ struct pv {
for (sbuf = buf; sbuf != NULL; sbuf = sbuf->next, dseg++) {
addr = rte_pktmbuf_mtod(sbuf, uintptr_t);
rte_prefetch0((volatile void *)addr);
- /* Handle WQE wraparound. */
- if (dseg >= (volatile struct mlx4_wqe_data_seg *)sq->eob)
- dseg = (volatile struct mlx4_wqe_data_seg *)sq->buf;
- dseg->addr = rte_cpu_to_be_64(addr);
/* Memory region key (big endian) for this memory pool. */
lkey = mlx4_txq_mp2mr(txq, mlx4_txq_mb2mp(sbuf));
dseg->lkey = rte_cpu_to_be_32(lkey);
/* Calculate the needed work queue entry size for this packet */
- if (unlikely(dseg->lkey == rte_cpu_to_be_32((uint32_t)-1))) {
+ if (unlikely(lkey == rte_cpu_to_be_32((uint32_t)-1))) {
/* MR does not exist. */
DEBUG("%p: unable to get MP <-> MR association",
(void *)txq);
@@ -501,6 +497,8 @@ struct pv {
* control segment.
*/
if ((uintptr_t)dseg & (uintptr_t)(MLX4_TXBB_SIZE - 1)) {
+ dseg->addr = rte_cpu_to_be_64(addr);
+ dseg->lkey = rte_cpu_to_be_32(lkey);
#if RTE_CACHE_LINE_SIZE < 64
/*
* Need a barrier here before writing the byte_count
@@ -520,6 +518,13 @@ struct pv {
* TXBB, so we need to postpone its byte_count writing
* for later.
*/
+ /* Handle WQE wraparound. */
+ if (dseg >=
+ (volatile struct mlx4_wqe_data_seg *)sq->eob)
+ dseg = (volatile struct mlx4_wqe_data_seg *)
+ sq->buf;
+ dseg->addr = rte_cpu_to_be_64(addr);
+ dseg->lkey = rte_cpu_to_be_32(lkey);
pv[pv_counter].dseg = dseg;
pv[pv_counter++].val = byte_count;
}
@@ -625,11 +630,6 @@ struct pv {
sizeof(struct mlx4_wqe_ctrl_seg));
addr = rte_pktmbuf_mtod(buf, uintptr_t);
rte_prefetch0((volatile void *)addr);
- /* Handle WQE wraparound. */
- if (dseg >=
- (volatile struct mlx4_wqe_data_seg *)sq->eob)
- dseg = (volatile struct mlx4_wqe_data_seg *)
- sq->buf;
dseg->addr = rte_cpu_to_be_64(addr);
/* Memory region key (big endian). */
lkey = mlx4_txq_mp2mr(txq, mlx4_txq_mb2mp(buf));