Hi all,
> From: Yoshihiro Shimoda, Sent: Tuesday, July 27, 2021 5:22 PM
>
> When we change the type of {cur,dirty}_tx from u32 to u8, we can
> reproduce this issue easily.
I'm afraid but I would like to recall this patch series because
the original code didn't have any issue around these counters
so that the patch series should not be applied.
For just a record, I tried to write why I misunderstood these counters are incorrect below:
- I got a report locally about an issue happen when the system sends/receives data in long time transfer
- So, I doubted these counters' overflow.
- To reproduce the issue quickly, I changed the type from u32 to u8.
- And then, the following condition will not work correctly (as I mentioned on the patch).
for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0; priv->dirty_tx[q]++) { --- [1]
- Also, I found if we used "> 0U" instead of "0", the issue disappeared.
for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0U; priv->dirty_tx[q]++) { --- [2]
~~
- However, today I got a report from our team member locally. The object code of
the get_num_desc() is just "from - subtract".
- If we use u32 as the original code, I realized the object codes between [1] and [2]
are the same.
- Also, I realized just priv->cur_tx[q] - priv->dirty_tx[q] is no problem.
- So, I would like to recall this patch series.
Best regards,
Yoshihiro Shimoda
