We can reduce code duplication in ravb_rx_gbeth().
Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
---
Changes v3->v4:
* Used switch statements instead of if statements in ravb_rx_gbeth().
drivers/net/ethernet/renesas/ravb_main.c | 73 +++++++++++++-----------
1 file changed, 40 insertions(+), 33 deletions(-)
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index 7df7d2e93a3a..c9c5cc641589 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -817,47 +817,54 @@ static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
stats->rx_missed_errors++;
} else {
die_dt = desc->die_dt & 0xF0;
+ skb = ravb_get_skb_gbeth(ndev, entry, desc);
switch (die_dt) {
case DT_FSINGLE:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
+ case DT_FSTART:
+ /* Start of packet:
+ * Set initial data length.
+ */
skb_put(skb, desc_len);
+
+ /* Save this SKB if the packet spans multiple
+ * descriptors.
+ */
+ if (die_dt == DT_FSTART)
+ priv->rx_1st_skb = skb;
+ break;
+
+ case DT_FMID:
+ case DT_FEND:
+ /* Continuing a packet:
+ * Move data into the saved SKB.
+ */
+ skb_copy_to_linear_data_offset(priv->rx_1st_skb,
+ priv->rx_1st_skb->len,
+ skb->data,
+ desc_len);
+ skb_put(priv->rx_1st_skb, desc_len);
+ dev_kfree_skb(skb);
+
+ /* Set skb to point at the whole packet so that
+ * we only need one code path for finishing a
+ * packet.
+ */
+ skb = priv->rx_1st_skb;
+ }
+
+ switch (die_dt) {
+ case DT_FSINGLE:
+ case DT_FEND:
+ /* Finishing a packet:
+ * Determine protocol & checksum, hand off to
+ * NAPI and update our stats.
+ */
skb->protocol = eth_type_trans(skb, ndev);
if (ndev->features & NETIF_F_RXCSUM)
ravb_rx_csum_gbeth(skb);
+ stats->rx_bytes += skb->len;
napi_gro_receive(&priv->napi[q], skb);
rx_packets++;
- stats->rx_bytes += desc_len;
- break;
- case DT_FSTART:
- priv->rx_1st_skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_put(priv->rx_1st_skb, desc_len);
- break;
- case DT_FMID:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_copy_to_linear_data_offset(priv->rx_1st_skb,
- priv->rx_1st_skb->len,
- skb->data,
- desc_len);
- skb_put(priv->rx_1st_skb, desc_len);
- dev_kfree_skb(skb);
- break;
- case DT_FEND:
- skb = ravb_get_skb_gbeth(ndev, entry, desc);
- skb_copy_to_linear_data_offset(priv->rx_1st_skb,
- priv->rx_1st_skb->len,
- skb->data,
- desc_len);
- skb_put(priv->rx_1st_skb, desc_len);
- dev_kfree_skb(skb);
- priv->rx_1st_skb->protocol =
- eth_type_trans(priv->rx_1st_skb, ndev);
- if (ndev->features & NETIF_F_RXCSUM)
- ravb_rx_csum_gbeth(priv->rx_1st_skb);
- stats->rx_bytes += priv->rx_1st_skb->len;
- napi_gro_receive(&priv->napi[q],
- priv->rx_1st_skb);
- rx_packets++;
- break;
}
}
}
--
2.39.2On 5/28/24 6:03 PM, Paul Barker wrote:
> We can reduce code duplication in ravb_rx_gbeth().
>
> Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
[...]
> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
> index 7df7d2e93a3a..c9c5cc641589 100644
> --- a/drivers/net/ethernet/renesas/ravb_main.c
> +++ b/drivers/net/ethernet/renesas/ravb_main.c
> @@ -817,47 +817,54 @@ static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
> stats->rx_missed_errors++;
> } else {
> die_dt = desc->die_dt & 0xF0;
> + skb = ravb_get_skb_gbeth(ndev, entry, desc);
> switch (die_dt) {
Why not do instead (as I've asked you alraedy):
case DT_FSTART:
priv->rx_1st_skb = skb;
fallthrough;
> case DT_FSINGLE:
> - skb = ravb_get_skb_gbeth(ndev, entry, desc);
> + case DT_FSTART:
> + /* Start of packet:
> + * Set initial data length.
> + */
Please consider turning that block comment into one-liner...
> skb_put(skb, desc_len);
> +
> + /* Save this SKB if the packet spans multiple
> + * descriptors.
> + */
This one too...
(The current line length limit is 100 columns.)
> + if (die_dt == DT_FSTART)
> + priv->rx_1st_skb = skb;
This needs to be done under *case* DT_FSTART above instead...
> + break;
> +
> + case DT_FMID:
> + case DT_FEND:
> + /* Continuing a packet:
> + * Move data into the saved SKB.
> + */
> + skb_copy_to_linear_data_offset(priv->rx_1st_skb,
> + priv->rx_1st_skb->len,
> + skb->data,
> + desc_len);
> + skb_put(priv->rx_1st_skb, desc_len);
> + dev_kfree_skb(skb);
> +
> + /* Set skb to point at the whole packet so that
Please call it consistently, either SKB or skb (I prefer this one).
> + * we only need one code path for finishing a
> + * packet.
> + */
> + skb = priv->rx_1st_skb;
> + }
> +
> + switch (die_dt) {
> + case DT_FSINGLE:
> + case DT_FEND:
> + /* Finishing a packet:
> + * Determine protocol & checksum, hand off to
> + * NAPI and update our stats.
> + */
> skb->protocol = eth_type_trans(skb, ndev);
> if (ndev->features & NETIF_F_RXCSUM)
> ravb_rx_csum_gbeth(skb);
> + stats->rx_bytes += skb->len;
> napi_gro_receive(&priv->napi[q], skb);
> rx_packets++;
Otherwise, this is very good patch! Sorry for letting in the duplcate
code earlier! :-)
[...]
MBR, Sergey
On 29/05/2024 19:30, Sergey Shtylyov wrote:
> On 5/28/24 6:03 PM, Paul Barker wrote:
>
>> We can reduce code duplication in ravb_rx_gbeth().
>>
>> Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
> [...]
>
>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
>> index 7df7d2e93a3a..c9c5cc641589 100644
>> --- a/drivers/net/ethernet/renesas/ravb_main.c
>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
>> @@ -817,47 +817,54 @@ static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
>> stats->rx_missed_errors++;
>> } else {
>> die_dt = desc->die_dt & 0xF0;
>> + skb = ravb_get_skb_gbeth(ndev, entry, desc);
>> switch (die_dt) {
>
> Why not do instead (as I've asked you alraedy):
>
> case DT_FSTART:
> priv->rx_1st_skb = skb;
> fallthrough;
I've avoided that change to keep patch 7/7 simpler (as we have to move
the assignment of skb later in that patch). I can change this if you
want though.
>
>> case DT_FSINGLE:
>> - skb = ravb_get_skb_gbeth(ndev, entry, desc);
>
>
>> + case DT_FSTART:
>> + /* Start of packet:
>> + * Set initial data length.
>> + */
>
> Please consider turning that block comment into one-liner...
Ack.
>
>> skb_put(skb, desc_len);
>> +
>> + /* Save this SKB if the packet spans multiple
>> + * descriptors.
>> + */
>
> This one too...
> (The current line length limit is 100 columns.)
Ack. I'll re-flow some other lines with a 100 col limit as well - I'm
immediately thinking of the skb_copy_to_linear_data_offset call below.
>
>> + if (die_dt == DT_FSTART)
>> + priv->rx_1st_skb = skb;
>
> This needs to be done under *case* DT_FSTART above instead...
See above comment. We can do this under DT_FSTART in this patch if you
want, but this if condition will then come back in a revised patch 7/7.
>
>> + break;
>> +
>> + case DT_FMID:
>> + case DT_FEND:
>> + /* Continuing a packet:
>> + * Move data into the saved SKB.
>> + */
>> + skb_copy_to_linear_data_offset(priv->rx_1st_skb,
>> + priv->rx_1st_skb->len,
>> + skb->data,
>> + desc_len);
>> + skb_put(priv->rx_1st_skb, desc_len);
>> + dev_kfree_skb(skb);
>> +
>> + /* Set skb to point at the whole packet so that
>
> Please call it consistently, either SKB or skb (I prefer this one).
Ack.
>
>> + * we only need one code path for finishing a
>> + * packet.
>> + */
>> + skb = priv->rx_1st_skb;
>> + }
>> +
>> + switch (die_dt) {
>> + case DT_FSINGLE:
>> + case DT_FEND:
>> + /* Finishing a packet:
>> + * Determine protocol & checksum, hand off to
>> + * NAPI and update our stats.
>> + */
>> skb->protocol = eth_type_trans(skb, ndev);
>> if (ndev->features & NETIF_F_RXCSUM)
>> ravb_rx_csum_gbeth(skb);
>> + stats->rx_bytes += skb->len;
>> napi_gro_receive(&priv->napi[q], skb);
>> rx_packets++;
>
> Otherwise, this is very good patch! Sorry for letting in the duplcate
> code earlier! :-)
>
> [...]
>
> MBR, Sergey
Thanks for the review!
--
Paul Barker
On 5/29/24 10:07 PM, Paul Barker wrote:
[...]
>>> We can reduce code duplication in ravb_rx_gbeth().
>>>
>>> Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
>> [...]
>>
>>> diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
>>> index 7df7d2e93a3a..c9c5cc641589 100644
>>> --- a/drivers/net/ethernet/renesas/ravb_main.c
>>> +++ b/drivers/net/ethernet/renesas/ravb_main.c
>>> @@ -817,47 +817,54 @@ static int ravb_rx_gbeth(struct net_device *ndev, int budget, int q)
>>> stats->rx_missed_errors++;
>>> } else {
>>> die_dt = desc->die_dt & 0xF0;
>>> + skb = ravb_get_skb_gbeth(ndev, entry, desc);
>>> switch (die_dt) {
>>
>> Why not do instead (as I've asked you alraedy):
Already. :-)
>>
>> case DT_FSTART:
>> priv->rx_1st_skb = skb;
>> fallthrough;
>
> I've avoided that change to keep patch 7/7 simpler (as we have to move
> the assignment of skb later in that patch). I can change this if you
> want though.
Oh, then please keep it as is! :-)
[...]
> Thanks for the review!
MBR, Sergey
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