2020-11-20 07:52:04

by Kaixu Xia

[permalink] [raw]
Subject: [PATCH] net: adaptec: remove dead code in set_vlan_mode

From: Kaixu Xia <[email protected]>

The body of the if statement can be executed only when the variable
vlan_count equals to 32, so the condition of the while statement can
not be true and the while statement is dead code. Remove it.

Reported-by: Tosk Robot <[email protected]>
Signed-off-by: Kaixu Xia <[email protected]>
---
drivers/net/ethernet/adaptec/starfire.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/adaptec/starfire.c b/drivers/net/ethernet/adaptec/starfire.c
index 555299737b51..ad27a9fa5e95 100644
--- a/drivers/net/ethernet/adaptec/starfire.c
+++ b/drivers/net/ethernet/adaptec/starfire.c
@@ -1754,14 +1754,9 @@ static u32 set_vlan_mode(struct netdev_private *np)
filter_addr += 16;
vlan_count++;
}
- if (vlan_count == 32) {
+ if (vlan_count == 32)
ret |= PerfectFilterVlan;
- while (vlan_count < 32) {
- writew(0, filter_addr);
- filter_addr += 16;
- vlan_count++;
- }
- }
+
return ret;
}
#endif /* VLAN_SUPPORT */
--
2.20.0


2020-11-20 23:20:53

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH] net: adaptec: remove dead code in set_vlan_mode

On Fri, 20 Nov 2020 15:50:00 +0800 [email protected] wrote:
> From: Kaixu Xia <[email protected]>
>
> The body of the if statement can be executed only when the variable
> vlan_count equals to 32, so the condition of the while statement can
> not be true and the while statement is dead code. Remove it.
>
> Reported-by: Tosk Robot <[email protected]>
> Signed-off-by: Kaixu Xia <[email protected]>
> ---
> drivers/net/ethernet/adaptec/starfire.c | 9 ++-------
> 1 file changed, 2 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/net/ethernet/adaptec/starfire.c b/drivers/net/ethernet/adaptec/starfire.c
> index 555299737b51..ad27a9fa5e95 100644
> --- a/drivers/net/ethernet/adaptec/starfire.c
> +++ b/drivers/net/ethernet/adaptec/starfire.c
> @@ -1754,14 +1754,9 @@ static u32 set_vlan_mode(struct netdev_private *np)
> filter_addr += 16;
> vlan_count++;
> }
> - if (vlan_count == 32) {
> + if (vlan_count == 32)
> ret |= PerfectFilterVlan;
> - while (vlan_count < 32) {
> - writew(0, filter_addr);
> - filter_addr += 16;
> - vlan_count++;
> - }
> - }
> +
> return ret;
> }
> #endif /* VLAN_SUPPORT */

This got broken back in 2011:

commit 5da96be53a16a62488316810d0c7c5d58ce3ee4f
Author: Jiri Pirko <[email protected]>
Date: Wed Jul 20 04:54:31 2011 +0000

starfire: do vlan cleanup

- unify vlan and nonvlan rx path
- kill np->vlgrp and netdev_vlan_rx_register

Signed-off-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

The comparison to 32 was on a different variable before that change.

Ion, do you think anyone is still using this driver?

Maybe it's time we put it in the history book (by which I mean remove
from the kernel).

2020-11-20 23:55:34

by Ion Badulescu

[permalink] [raw]
Subject: Re: [PATCH] net: adaptec: remove dead code in set_vlan_mode

On 11/20/20 6:17 PM, Jakub Kicinski wrote:
> On Fri, 20 Nov 2020 15:50:00 +0800 [email protected] wrote:
>> From: Kaixu Xia <[email protected]>
>>
>> The body of the if statement can be executed only when the variable
>> vlan_count equals to 32, so the condition of the while statement can
>> not be true and the while statement is dead code. Remove it.
>>
>> Reported-by: Tosk Robot <[email protected]>
>> Signed-off-by: Kaixu Xia <[email protected]>
>> ---
>> drivers/net/ethernet/adaptec/starfire.c | 9 ++-------
>> 1 file changed, 2 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/adaptec/starfire.c b/drivers/net/ethernet/adaptec/starfire.c
>> index 555299737b51..ad27a9fa5e95 100644
>> --- a/drivers/net/ethernet/adaptec/starfire.c
>> +++ b/drivers/net/ethernet/adaptec/starfire.c
>> @@ -1754,14 +1754,9 @@ static u32 set_vlan_mode(struct netdev_private *np)
>> filter_addr += 16;
>> vlan_count++;
>> }
>> - if (vlan_count == 32) {
>> + if (vlan_count == 32)
>> ret |= PerfectFilterVlan;
>> - while (vlan_count < 32) {
>> - writew(0, filter_addr);
>> - filter_addr += 16;
>> - vlan_count++;
>> - }
>> - }
>> +
>> return ret;
>> }
>> #endif /* VLAN_SUPPORT */
>
> This got broken back in 2011:
>
> commit 5da96be53a16a62488316810d0c7c5d58ce3ee4f
> Author: Jiri Pirko <[email protected]>
> Date: Wed Jul 20 04:54:31 2011 +0000
>
> starfire: do vlan cleanup
>
> - unify vlan and nonvlan rx path
> - kill np->vlgrp and netdev_vlan_rx_register
>
> Signed-off-by: Jiri Pirko <[email protected]>
> Signed-off-by: David S. Miller <[email protected]>
>
> The comparison to 32 was on a different variable before that change.
>
> Ion, do you think anyone is still using this driver?
>
> Maybe it's time we put it in the history book (by which I mean remove
> from the kernel).

Frankly, no, I don't know of any users, and that unfortunately includes
myself. I still have two cards in my stash, but they're 64-bit PCI-X, so
plugging them in would likely require taking a dremel to a 32-bit PCI
slot to make it open-ended. (They do work in a 32-bit slot.)

Anyway, that filter code could use some fixing in other regards. So
either we fix it properly (which I can submit a patch for), or clean it
out for good.

-Ion

2020-11-20 23:58:44

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH] net: adaptec: remove dead code in set_vlan_mode

On Fri, 20 Nov 2020 18:41:03 -0500 Ion Badulescu wrote:
> Frankly, no, I don't know of any users, and that unfortunately includes
> myself. I still have two cards in my stash, but they're 64-bit PCI-X, so
> plugging them in would likely require taking a dremel to a 32-bit PCI
> slot to make it open-ended. (They do work in a 32-bit slot.)
>
> Anyway, that filter code could use some fixing in other regards. So
> either we fix it properly (which I can submit a patch for), or clean it
> out for good.

Entirely up to you.

2020-11-21 00:21:00

by Ion Badulescu

[permalink] [raw]
Subject: Re: [PATCH] net: adaptec: remove dead code in set_vlan_mode

On 11/20/20 6:56 PM, Jakub Kicinski wrote:
> On Fri, 20 Nov 2020 18:41:03 -0500 Ion Badulescu wrote:
>> Frankly, no, I don't know of any users, and that unfortunately includes
>> myself. I still have two cards in my stash, but they're 64-bit PCI-X, so
>> plugging them in would likely require taking a dremel to a 32-bit PCI
>> slot to make it open-ended. (They do work in a 32-bit slot.)
>>
>> Anyway, that filter code could use some fixing in other regards. So
>> either we fix it properly (which I can submit a patch for), or clean it
>> out for good.
>
> Entirely up to you.

All right then. I'll whip out the Dremel this weekend and hopefully get
a test rig going... :)

-Ion