[PATCH] RDMA/rxe: No need to check IPV6 in rxe_find_route

[PATCH] RDMA/rxe: No need to check IPV6 in rxe_find_route

[Guoqing Jiang]

This check is unnecessary since rxe_find_route6 returns NULL if
CONFIG_IPV6 is disabled.

Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
---
 drivers/infiniband/sw/rxe/rxe_net.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
index c53f4529f098..b0f31f849144 100644
--- a/drivers/infiniband/sw/rxe/rxe_net.c
+++ b/drivers/infiniband/sw/rxe/rxe_net.c
@@ -113,11 +113,9 @@ static struct dst_entry *rxe_find_route(struct net_device *ndev,
 			saddr6 = &av->sgid_addr._sockaddr_in6.sin6_addr;
 			daddr6 = &av->dgid_addr._sockaddr_in6.sin6_addr;
 			dst = rxe_find_route6(ndev, saddr6, daddr6);
-#if IS_ENABLED(CONFIG_IPV6)
 			if (dst)
 				qp->dst_cookie =
 					rt6_get_cookie((struct rt6_info *)dst);
-#endif
 		}
 
 		if (dst && (qp_type(qp) == IB_QPT_RC)) {
-- 
2.31.1

Re: [PATCH] RDMA/rxe: No need to check IPV6 in rxe_find_route

[William Kucharski]

Rather than remove the #if guard here, shouldn't it instead be expanded
to cover the entire

    else if (av->network_type == RXE_NETWORK_TYPE_IPV6) {

clause?

There is no need to check for RXE_NETWORK_TYPE_IPV6, make assignments
to the stack-allocated pointers or call rxe_find_route6() unless
CONFIG_IPV6 is true.

In fact, if CONFIG_IPV6 is false, as rxe_find_route6 would also return
NULL, the else clause to the RXE_NETWORK_TYPE_IPV4 check could instead
become a simple

    return NULL;

> On Aug 22, 2022, at 5:23 AM, Guoqing Jiang <guoqing.jiang@linux.dev> wrote:
> 
> This check is unnecessary since rxe_find_route6 returns NULL if
> CONFIG_IPV6 is disabled.
> 
> Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
> ---
> drivers/infiniband/sw/rxe/rxe_net.c | 2 --
> 1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> index c53f4529f098..b0f31f849144 100644
> --- a/drivers/infiniband/sw/rxe/rxe_net.c
> +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> @@ -113,11 +113,9 @@ static struct dst_entry *rxe_find_route(struct net_device *ndev,
> saddr6 = &av->sgid_addr._sockaddr_in6.sin6_addr;
> daddr6 = &av->dgid_addr._sockaddr_in6.sin6_addr;
> dst = rxe_find_route6(ndev, saddr6, daddr6);
> -#if IS_ENABLED(CONFIG_IPV6)
> if (dst)
> qp->dst_cookie =
> rt6_get_cookie((struct rt6_info *)dst);
> -#endif
> }
> 
> if (dst && (qp_type(qp) == IB_QPT_RC)) {
> -- 
> 2.31.1
> 

Re: [PATCH] RDMA/rxe: No need to check IPV6 in rxe_find_route

[kernel test robot]

Hi Guoqing,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on rdma/for-next]
[also build test ERROR on linus/master v6.0-rc2 next-20220822]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Guoqing-Jiang/RDMA-rxe-No-need-to-check-IPV6-in-rxe_find_route/20220822-192520
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git for-next
config: ia64-buildonly-randconfig-r005-20220822 (https://download.01.org/0day-ci/archive/20220823/202208230225.DS04ZlXH-lkp@intel.com/config)
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/9d154e806104f75aae6c66dfd78ecd5e67c7e00d
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Guoqing-Jiang/RDMA-rxe-No-need-to-check-IPV6-in-rxe_find_route/20220822-192520
        git checkout 9d154e806104f75aae6c66dfd78ecd5e67c7e00d
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash drivers/infiniband/sw/rxe/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/infiniband/sw/rxe/rxe_net.c: In function 'rxe_find_route':
>> drivers/infiniband/sw/rxe/rxe_net.c:118:41: error: implicit declaration of function 'rt6_get_cookie' [-Werror=implicit-function-declaration]
     118 |                                         rt6_get_cookie((struct rt6_info *)dst);
         |                                         ^~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/rt6_get_cookie +118 drivers/infiniband/sw/rxe/rxe_net.c

8700e3e7c4857d Moni Shoua      2016-06-16   88  
3db2bceb29fd9a Parav Pandit    2018-08-28   89  static struct dst_entry *rxe_find_route(struct net_device *ndev,
4ed6ad1eb30e20 yonatanc        2017-04-20   90  					struct rxe_qp *qp,
4ed6ad1eb30e20 yonatanc        2017-04-20   91  					struct rxe_av *av)
4ed6ad1eb30e20 yonatanc        2017-04-20   92  {
4ed6ad1eb30e20 yonatanc        2017-04-20   93  	struct dst_entry *dst = NULL;
4ed6ad1eb30e20 yonatanc        2017-04-20   94  
4ed6ad1eb30e20 yonatanc        2017-04-20   95  	if (qp_type(qp) == IB_QPT_RC)
4ed6ad1eb30e20 yonatanc        2017-04-20   96  		dst = sk_dst_get(qp->sk->sk);
4ed6ad1eb30e20 yonatanc        2017-04-20   97  
b9109b7ddb13a5 Andrew Boyer    2017-08-28   98  	if (!dst || !dst_check(dst, qp->dst_cookie)) {
4ed6ad1eb30e20 yonatanc        2017-04-20   99  		if (dst)
4ed6ad1eb30e20 yonatanc        2017-04-20  100  			dst_release(dst);
4ed6ad1eb30e20 yonatanc        2017-04-20  101  
e0d696d201dd5d Jason Gunthorpe 2020-10-15  102  		if (av->network_type == RXE_NETWORK_TYPE_IPV4) {
4ed6ad1eb30e20 yonatanc        2017-04-20  103  			struct in_addr *saddr;
4ed6ad1eb30e20 yonatanc        2017-04-20  104  			struct in_addr *daddr;
4ed6ad1eb30e20 yonatanc        2017-04-20  105  
4ed6ad1eb30e20 yonatanc        2017-04-20  106  			saddr = &av->sgid_addr._sockaddr_in.sin_addr;
4ed6ad1eb30e20 yonatanc        2017-04-20  107  			daddr = &av->dgid_addr._sockaddr_in.sin_addr;
43c9fc509fa59d Martin Wilck    2018-02-14  108  			dst = rxe_find_route4(ndev, saddr, daddr);
e0d696d201dd5d Jason Gunthorpe 2020-10-15  109  		} else if (av->network_type == RXE_NETWORK_TYPE_IPV6) {
4ed6ad1eb30e20 yonatanc        2017-04-20  110  			struct in6_addr *saddr6;
4ed6ad1eb30e20 yonatanc        2017-04-20  111  			struct in6_addr *daddr6;
4ed6ad1eb30e20 yonatanc        2017-04-20  112  
4ed6ad1eb30e20 yonatanc        2017-04-20  113  			saddr6 = &av->sgid_addr._sockaddr_in6.sin6_addr;
4ed6ad1eb30e20 yonatanc        2017-04-20  114  			daddr6 = &av->dgid_addr._sockaddr_in6.sin6_addr;
43c9fc509fa59d Martin Wilck    2018-02-14  115  			dst = rxe_find_route6(ndev, saddr6, daddr6);
b9109b7ddb13a5 Andrew Boyer    2017-08-28  116  			if (dst)
b9109b7ddb13a5 Andrew Boyer    2017-08-28  117  				qp->dst_cookie =
b9109b7ddb13a5 Andrew Boyer    2017-08-28 @118  					rt6_get_cookie((struct rt6_info *)dst);
4ed6ad1eb30e20 yonatanc        2017-04-20  119  		}
24c937b39dfb10 Vijay Immanuel  2018-06-18  120  
24c937b39dfb10 Vijay Immanuel  2018-06-18  121  		if (dst && (qp_type(qp) == IB_QPT_RC)) {
24c937b39dfb10 Vijay Immanuel  2018-06-18  122  			dst_hold(dst);
24c937b39dfb10 Vijay Immanuel  2018-06-18  123  			sk_dst_set(qp->sk->sk, dst);
24c937b39dfb10 Vijay Immanuel  2018-06-18  124  		}
4ed6ad1eb30e20 yonatanc        2017-04-20  125  	}
4ed6ad1eb30e20 yonatanc        2017-04-20  126  	return dst;
4ed6ad1eb30e20 yonatanc        2017-04-20  127  }
4ed6ad1eb30e20 yonatanc        2017-04-20  128  

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [PATCH] RDMA/rxe: No need to check IPV6 in rxe_find_route

[Guoqing Jiang]

On 8/23/22 12:33 AM, William Kucharski wrote:
> Rather than remove the #if guard here, shouldn't it instead be expanded
> to cover the entire
>
>      else if (av->network_type == RXE_NETWORK_TYPE_IPV6) {
>
> clause?
>
> There is no need to check for RXE_NETWORK_TYPE_IPV6, make assignments
> to the stack-allocated pointers or call rxe_find_route6() unless
> CONFIG_IPV6 is true.
>
> In fact, if CONFIG_IPV6 is false, as rxe_find_route6 would also return
> NULL, the else clause to the RXE_NETWORK_TYPE_IPV4 check could instead
> become a simple
>
>      return NULL;

Thanks for the suggestion! And it could also resolve the issue reported by
LKP too.

Thanks,
Guoqing