net/octeontx2: remove logically dead code

Message ID ca775c2d9670d3133515c6abd81acedf3c19222c.1598418485.git.wangyunjian@huawei.com (mailing list archive)
State Changes Requested, archived
Delegated to: Jerin Jacob
Headers
Series net/octeontx2: remove logically dead code |

Checks

Context Check Description
ci/Intel-compilation success Compilation OK
ci/travis-robot success Travis build: passed
ci/iol-testing success Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/checkpatch success coding style OK

Commit Message

Yunjian Wang Aug. 26, 2020, 11:18 a.m. UTC
  From: Yunjian Wang <wangyunjian@huawei.com>

Coverity issue: 357719
Fixes: da138cd47e06 ("net/octeontx2: handle port reconfigure")
Cc: stable@dpdk.org

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
---
 drivers/net/octeontx2/otx2_ethdev.c | 2 --
 1 file changed, 2 deletions(-)
  

Comments

Jerin Jacob Sept. 29, 2020, 6:14 p.m. UTC | #1
On Wed, Aug 26, 2020 at 4:48 PM wangyunjian <wangyunjian@huawei.com> wrote:
>
> From: Yunjian Wang <wangyunjian@huawei.com>
>
> Coverity issue: 357719
> Fixes: da138cd47e06 ("net/octeontx2: handle port reconfigure")
> Cc: stable@dpdk.org
>
> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
> ---
>  drivers/net/octeontx2/otx2_ethdev.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/drivers/net/octeontx2/otx2_ethdev.c b/drivers/net/octeontx2/otx2_ethdev.c
> index 33b72bd4d..3f9399cc8 100644
> --- a/drivers/net/octeontx2/otx2_ethdev.c
> +++ b/drivers/net/octeontx2/otx2_ethdev.c
> @@ -1355,8 +1355,6 @@ nix_store_queue_cfg_and_then_release(struct rte_eth_dev *eth_dev)
>  fail:

See below

>         if (tx_qconf)
>                 free(tx_qconf);
> -       if (rx_qconf)
> -               free(rx_qconf);

I think, it is clean and maintainable code have free() if rx_qconf as
if we add some another
exit error case in the future, we simply forget to add this check and
it will fail. So I prefer to keep
as-is for the sake of maintainability as there is no harm.


>
>         return -ENOMEM;
>  }
> --
> 2.23.0
>
>
  
Stephen Hemminger Sept. 29, 2020, 7:57 p.m. UTC | #2
On Wed, 26 Aug 2020 19:18:09 +0800
wangyunjian <wangyunjian@huawei.com> wrote:

>  	if (tx_qconf)
>  		free(tx_qconf);
> -	if (rx_qconf)
> -		free(rx_qconf);

free accepts a NULL pointer so current practice is to avoid
useless if() tests before free.
  
Yunjian Wang Sept. 30, 2020, 10:34 a.m. UTC | #3
> -----Original Message-----
> From: Jerin Jacob [mailto:jerinjacobk@gmail.com]
> Sent: Wednesday, September 30, 2020 2:15 AM
> To: wangyunjian <wangyunjian@huawei.com>
> Cc: dpdk-dev <dev@dpdk.org>; Jerin Jacob <jerinj@marvell.com>; Nithin
> Dabilpuram <ndabilpuram@marvell.com>; Kiran Kumar K
> <kirankumark@marvell.com>; Lilijun (Jerry) <jerry.lilijun@huawei.com>;
> xudingke <xudingke@huawei.com>; dpdk stable <stable@dpdk.org>
> Subject: Re: [dpdk-dev] [PATCH] net/octeontx2: remove logically dead code
> 
> On Wed, Aug 26, 2020 at 4:48 PM wangyunjian <wangyunjian@huawei.com>
> wrote:
> >
> > From: Yunjian Wang <wangyunjian@huawei.com>
> >
> > Coverity issue: 357719
> > Fixes: da138cd47e06 ("net/octeontx2: handle port reconfigure")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
> > ---
> >  drivers/net/octeontx2/otx2_ethdev.c | 2 --
> >  1 file changed, 2 deletions(-)
> >
> > diff --git a/drivers/net/octeontx2/otx2_ethdev.c
> > b/drivers/net/octeontx2/otx2_ethdev.c
> > index 33b72bd4d..3f9399cc8 100644
> > --- a/drivers/net/octeontx2/otx2_ethdev.c
> > +++ b/drivers/net/octeontx2/otx2_ethdev.c
> > @@ -1355,8 +1355,6 @@ nix_store_queue_cfg_and_then_release(struct
> > rte_eth_dev *eth_dev)
> >  fail:
> 
> See below
> 
> >         if (tx_qconf)
> >                 free(tx_qconf);
> > -       if (rx_qconf)
> > -               free(rx_qconf);
> 
> I think, it is clean and maintainable code have free() if rx_qconf as if we add
> some another exit error case in the future, we simply forget to add this check
> and it will fail. So I prefer to keep as-is for the sake of maintainability as there is
> no harm.

Hi, Jerin

Thanks for your explanation.
According to Stephen's suggestion, is it need to remove unnecessary NULL check?

Thanks,
Yunjian

> 
> 
> >
> >         return -ENOMEM;
> >  }
> > --
> > 2.23.0
> >
> >
  
Jerin Jacob Oct. 4, 2020, 8:52 a.m. UTC | #4
On Wed, Sep 30, 2020 at 4:04 PM wangyunjian <wangyunjian@huawei.com> wrote:
>
> > -----Original Message-----
> > From: Jerin Jacob [mailto:jerinjacobk@gmail.com]
> > Sent: Wednesday, September 30, 2020 2:15 AM
> > To: wangyunjian <wangyunjian@huawei.com>
> > Cc: dpdk-dev <dev@dpdk.org>; Jerin Jacob <jerinj@marvell.com>; Nithin
> > Dabilpuram <ndabilpuram@marvell.com>; Kiran Kumar K
> > <kirankumark@marvell.com>; Lilijun (Jerry) <jerry.lilijun@huawei.com>;
> > xudingke <xudingke@huawei.com>; dpdk stable <stable@dpdk.org>
> > Subject: Re: [dpdk-dev] [PATCH] net/octeontx2: remove logically dead code
> >
> > On Wed, Aug 26, 2020 at 4:48 PM wangyunjian <wangyunjian@huawei.com>
> > wrote:
> > >
> > > From: Yunjian Wang <wangyunjian@huawei.com>
> > >
> > > Coverity issue: 357719
> > > Fixes: da138cd47e06 ("net/octeontx2: handle port reconfigure")
> > > Cc: stable@dpdk.org
> > >
> > > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
> > > ---
> > >  drivers/net/octeontx2/otx2_ethdev.c | 2 --
> > >  1 file changed, 2 deletions(-)
> > >
> > > diff --git a/drivers/net/octeontx2/otx2_ethdev.c
> > > b/drivers/net/octeontx2/otx2_ethdev.c
> > > index 33b72bd4d..3f9399cc8 100644
> > > --- a/drivers/net/octeontx2/otx2_ethdev.c
> > > +++ b/drivers/net/octeontx2/otx2_ethdev.c
> > > @@ -1355,8 +1355,6 @@ nix_store_queue_cfg_and_then_release(struct
> > > rte_eth_dev *eth_dev)
> > >  fail:
> >
> > See below
> >
> > >         if (tx_qconf)
> > >                 free(tx_qconf);
> > > -       if (rx_qconf)
> > > -               free(rx_qconf);
> >
> > I think, it is clean and maintainable code have free() if rx_qconf as if we add
> > some another exit error case in the future, we simply forget to add this check
> > and it will fail. So I prefer to keep as-is for the sake of maintainability as there is
> > no harm.
>
> Hi, Jerin
>
> Thanks for your explanation.
> According to Stephen's suggestion, is it need to remove unnecessary NULL check?

Yes. Makes sense to remove if check.

>
> Thanks,
> Yunjian
>
> >
> >
> > >
> > >         return -ENOMEM;
> > >  }
> > > --
> > > 2.23.0
> > >
> > >
  

Patch

diff --git a/drivers/net/octeontx2/otx2_ethdev.c b/drivers/net/octeontx2/otx2_ethdev.c
index 33b72bd4d..3f9399cc8 100644
--- a/drivers/net/octeontx2/otx2_ethdev.c
+++ b/drivers/net/octeontx2/otx2_ethdev.c
@@ -1355,8 +1355,6 @@  nix_store_queue_cfg_and_then_release(struct rte_eth_dev *eth_dev)
 fail:
 	if (tx_qconf)
 		free(tx_qconf);
-	if (rx_qconf)
-		free(rx_qconf);
 
 	return -ENOMEM;
 }