* Re: [PATCH] wifi: rtl8xxxu: correct the error value of 'timeout'
2023-11-14 6:42 ` Ping-Ke Shih
@ 2023-11-14 9:17 ` Su Hui
2023-11-20 12:31 ` Dan Carpenter
1 sibling, 0 replies; 4+ messages in thread
From: Su Hui @ 2023-11-14 9:17 UTC (permalink / raw)
To: Ping-Ke Shih, Jes.Sorensen@gmail.com, kvalo@kernel.org
Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org
On 2023/11/14 14:42, Ping-Ke Shih wrote:
>> -----Original Message-----
>> From: Su Hui <suhui@nfschina.com>
>> Sent: Monday, November 13, 2023 1:49 PM
>> To: Jes.Sorensen@gmail.com; kvalo@kernel.org
>> Cc: Su Hui <suhui@nfschina.com>; linux-wireless@vger.kernel.org; linux-kernel@vger.kernel.org;
>> kernel-janitors@vger.kernel.org
>> Subject: [PATCH] wifi: rtl8xxxu: correct the error value of 'timeout'
>>
>> When 'rtl8xxxu_dma_agg_pages <= page_thresh', 'timeout' should equal to
>> 'page_thresh' rather than '4'. Change the code order to fix this problem.
>>
>> Fixes: 614e389f36a9 ("rtl8xxxu: gen1: Set aggregation timeout (REG_RXDMA_AGG_PG_TH + 1) as well")
> I think this should fix
> Fixes: fd83f1227826 ("rtl8xxxu: gen1: Add module parameters to adjust DMA aggregation parameters")
Agreed. Thanks for your reminder!
>
>> Signed-off-by: Su Hui <suhui@nfschina.com>
>> ---
>> .../net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 12 ++++++------
>> 1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> index 43ee7592bc6e..9cab8b1dc486 100644
>> --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> @@ -4757,6 +4757,12 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv)
>> * RxAggPageTimeout = 4 or 6 (absolute time 34ms/(2^6))
>> */
>>
>> + /* REG_RXDMA_AGG_PG_TH + 1 seems to be the timeout register on
>> + * gen2 chips and rtl8188eu. The rtl8723au seems unhappy if we
>> + * don't set it, so better set both.
>> + */
>> + timeout = 4;
>> +
>> page_thresh = (priv->fops->rx_agg_buf_size / 512);
>> if (rtl8xxxu_dma_agg_pages >= 0) {
>> if (rtl8xxxu_dma_agg_pages <= page_thresh)
> The logic here is:
>
> page_thresh = (priv->fops->rx_agg_buf_size / 512);
> if (rtl8xxxu_dma_agg_pages >= 0) {
> if (rtl8xxxu_dma_agg_pages <= page_thresh)
> timeout = page_thresh;
>
> Do you know why 'timeout = page_thresh;'? Intuitively, units of 'timeout' and
> 'thresh' are different. Maybe, we should correct here instead?
I don't know the reason about this. :(
I found this error because clang static checker complains about this
code that value stored to 'timeout'
is never read.
Su Hui
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] wifi: rtl8xxxu: correct the error value of 'timeout'
2023-11-14 6:42 ` Ping-Ke Shih
2023-11-14 9:17 ` Su Hui
@ 2023-11-20 12:31 ` Dan Carpenter
1 sibling, 0 replies; 4+ messages in thread
From: Dan Carpenter @ 2023-11-20 12:31 UTC (permalink / raw)
To: Ping-Ke Shih
Cc: Su Hui, Jes.Sorensen@gmail.com, kvalo@kernel.org,
linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org
On Tue, Nov 14, 2023 at 06:42:50AM +0000, Ping-Ke Shih wrote:
> > diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> > b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> > index 43ee7592bc6e..9cab8b1dc486 100644
> > --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> > +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> > @@ -4757,6 +4757,12 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv)
> > * RxAggPageTimeout = 4 or 6 (absolute time 34ms/(2^6))
> > */
> >
> > + /* REG_RXDMA_AGG_PG_TH + 1 seems to be the timeout register on
> > + * gen2 chips and rtl8188eu. The rtl8723au seems unhappy if we
> > + * don't set it, so better set both.
> > + */
> > + timeout = 4;
> > +
> > page_thresh = (priv->fops->rx_agg_buf_size / 512);
> > if (rtl8xxxu_dma_agg_pages >= 0) {
> > if (rtl8xxxu_dma_agg_pages <= page_thresh)
>
> The logic here is:
>
> page_thresh = (priv->fops->rx_agg_buf_size / 512);
> if (rtl8xxxu_dma_agg_pages >= 0) {
> if (rtl8xxxu_dma_agg_pages <= page_thresh)
> timeout = page_thresh;
>
> Do you know why 'timeout = page_thresh;'? Intuitively, units of 'timeout' and
> 'thresh' are different. Maybe, we should correct here instead?
>
Yeah. That's strange. I'm not convinced this fix is correct. I'm
hesitant to suggest this but maybe the following is the correct fix?
It just silences the warning but doesn't change runtime.
I don't know. *shrug*. One thing that we could do is just leave the
warning as-is until someone who knows better than we do can take a look
at it.
regards,
dan carpenter
diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index 43ee7592bc6e..68d9b4a0ee63 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -4759,16 +4759,16 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv)
page_thresh = (priv->fops->rx_agg_buf_size / 512);
if (rtl8xxxu_dma_agg_pages >= 0) {
- if (rtl8xxxu_dma_agg_pages <= page_thresh)
- timeout = page_thresh;
- else if (rtl8xxxu_dma_agg_pages <= 6)
- dev_err(&priv->udev->dev,
- "%s: dma_agg_pages=%i too small, minimum is 6\n",
- __func__, rtl8xxxu_dma_agg_pages);
- else
- dev_err(&priv->udev->dev,
- "%s: dma_agg_pages=%i larger than limit %i\n",
- __func__, rtl8xxxu_dma_agg_pages, page_thresh);
+ if (rtl8xxxu_dma_agg_pages > page_thresh) {
+ if (rtl8xxxu_dma_agg_pages <= 6)
+ dev_err(&priv->udev->dev,
+ "%s: dma_agg_pages=%i too small, minimum is 6\n",
+ __func__, rtl8xxxu_dma_agg_pages);
+ else
+ dev_err(&priv->udev->dev,
+ "%s: dma_agg_pages=%i larger than limit %i\n",
+ __func__, rtl8xxxu_dma_agg_pages, page_thresh);
+ }
}
rtl8xxxu_write8(priv, REG_RXDMA_AGG_PG_TH, page_thresh);
/*
^ permalink raw reply related [flat|nested] 4+ messages in thread