[dpdk-dev] [PATCH] net/mlx5: fix queue wrap-around of multi-packet send

[dpdk-dev] [PATCH] net/mlx5: fix queue wrap-around of multi-packet send

[Yongseok Koh]

When the WQ is wrapped around, it wrongly checks the condition when
resetting the pointer. It should be compared against the end of the queue,
not the beginning of the queue. And this isn't even needed when the length
of the copying data crosses the boundary.

Fixes: e5291c280c08 ("net/mlx5: use work queue buffer as a raw buffer")

CC: stable@dpdk.org
Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
---
 drivers/net/mlx5/mlx5_rxtx.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index 2ae949295..f54db5b85 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -1037,11 +1037,13 @@ mlx5_tx_burst_mpw_inline(void *dpdk_txq, struct rte_mbuf **pkts,
 				rte_memcpy((void *)(uintptr_t)mpw.data.raw,
 					   (void *)addr,
 					   length);
-				mpw.data.raw += length;
+
+				if (length == max)
+					mpw.data.raw =
+						(volatile void *)txq->wqes;
+				else
+					mpw.data.raw += length;
 			}
-			if ((uintptr_t)mpw.data.raw ==
-			    (uintptr_t)tx_mlx5_wqe(txq, 1 << txq->wqe_n))
-				mpw.data.raw = (volatile void *)txq->wqes;
 			++mpw.pkts_n;
 			++j;
 			if (mpw.pkts_n == MLX5_MPW_DSEG_MAX) {
-- 
2.11.0

Re: [dpdk-dev] [PATCH] net/mlx5: fix queue wrap-around of multi-packet send

[Adrien Mazarguil]

On Tue, Jan 17, 2017 at 04:51:55PM -0800, Yongseok Koh wrote:
> When the WQ is wrapped around, it wrongly checks the condition when
> resetting the pointer. It should be compared against the end of the queue,
> not the beginning of the queue. And this isn't even needed when the length
> of the copying data crosses the boundary.
> 
> Fixes: e5291c280c08 ("net/mlx5: use work queue buffer as a raw buffer")
> 
> CC: stable@dpdk.org
> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
> ---
>  drivers/net/mlx5/mlx5_rxtx.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)

Thanks for addressing this issue.

Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

-- 
Adrien Mazarguil
6WIND

Re: [dpdk-dev] [PATCH] net/mlx5: fix queue wrap-around of multi-packet send

[Ferruh Yigit]

On 1/20/2017 4:56 PM, Adrien Mazarguil wrote:
> On Tue, Jan 17, 2017 at 04:51:55PM -0800, Yongseok Koh wrote:
>> When the WQ is wrapped around, it wrongly checks the condition when
>> resetting the pointer. It should be compared against the end of the queue,
>> not the beginning of the queue. And this isn't even needed when the length
>> of the copying data crosses the boundary.
>>
>> Fixes: e5291c280c08 ("net/mlx5: use work queue buffer as a raw buffer")
>>
>> CC: stable@dpdk.org
>> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
>> ---
>>  drivers/net/mlx5/mlx5_rxtx.c | 10 ++++++----
>>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> Thanks for addressing this issue.
> 
> Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

Fixes: fdcb0f53053b ("net/mlx5: use work queue buffer as a raw buffer")
Applied to dpdk-next-net/master, thanks.