Re: [PATCH v1 iproute2-next 1/4] rdma: add helper rd_sendrecv_msg()

[Steve Wise <swise@opengridcomputing.com>]

On 2/23/2019 3:26 AM, Leon Romanovsky wrote:
> On Thu, Feb 21, 2019 at 08:19:03AM -0800, Steve Wise wrote:
>> This function sends the constructed netlink message and then
>> receives the response, displaying any error text.
>>
>> Change 'rdma dev set' to use it.
>>
>> Signed-off-by: Steve Wise <swise@opengridcomputing.com>
>> ---
>>  rdma/dev.c   |  2 +-
>>  rdma/rdma.h  |  1 +
>>  rdma/utils.c | 21 +++++++++++++++++++++
>>  3 files changed, 23 insertions(+), 1 deletion(-)
>>
>> diff --git a/rdma/dev.c b/rdma/dev.c
>> index 60ff4b31e320..d2949c378f08 100644
>> --- a/rdma/dev.c
>> +++ b/rdma/dev.c
>> @@ -273,7 +273,7 @@ static int dev_set_name(struct rd *rd)
>>  	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
>>  	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, rd_argv(rd));
>>
>> -	return rd_send_msg(rd);
>> +	return rd_sendrecv_msg(rd, seq);
>>  }
>>
>>  static int dev_one_set(struct rd *rd)
>> diff --git a/rdma/rdma.h b/rdma/rdma.h
>> index 547bb5749a39..20be2f12c4f8 100644
>> --- a/rdma/rdma.h
>> +++ b/rdma/rdma.h
>> @@ -115,6 +115,7 @@ bool rd_check_is_key_exist(struct rd *rd, const char *key);
>>   */
>>  int rd_send_msg(struct rd *rd);
>>  int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, uint32_t seq);
>> +int rd_sendrecv_msg(struct rd *rd, unsigned int seq);
>>  void rd_prepare_msg(struct rd *rd, uint32_t cmd, uint32_t *seq, uint16_t flags);
>>  int rd_dev_init_cb(const struct nlmsghdr *nlh, void *data);
>>  int rd_attr_cb(const struct nlattr *attr, void *data);
>> diff --git a/rdma/utils.c b/rdma/utils.c
>> index 069d44fece10..a6f2826c9605 100644
>> --- a/rdma/utils.c
>> +++ b/rdma/utils.c
>> @@ -664,6 +664,27 @@ int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, unsigned int seq)
>>  	return ret;
>>  }
>>
>> +static int null_cb(const struct nlmsghdr *nlh, void *data)
>> +{
>> +	return MNL_CB_OK;
>> +}
>> +
>> +int rd_sendrecv_msg(struct rd *rd, unsigned int seq)
>> +{
>> +	int ret;
>> +
>> +	ret = rd_send_msg(rd);
>> +	if (ret) {
>> +		perror(NULL);
> This is more or less already done in rd_send_msg() and that function
> prints something in case of execution error. So the missing piece
> is to update rd_recv_msg(), so all places will "magically" print errors
> and not only dev_set_name().

Hey Leon,

Displaying errors in rd_recv_msg() as you suggested:

@@ -693,10 +693,28 @@ int rd_recv_msg(struct rd *rd, mnl_cb_t callback,
void *data, unsigned int seq)
                ret = mnl_cb_run(buf, ret, seq, portid, callback, data);
        } while (ret > 0);

+       if (ret < 0)
+               perror(NULL);
+
        mnl_socket_close(rd->nl);
        return ret;
 }

Causes problems when doing filtered dumps:

[root@stevo1 iproute2]# ./rdma/rdma res show qp
link mlx5_0/1 lqpn 1 type GSI state RTS sq-psn 0 comm [ib_core]
link mlx5_0/1 lqpn 176 type UD state RTS sq-psn 0 comm [ib_core]
link mlx5_1/1 lqpn 1 type GSI state RTS sq-psn 0 comm [ib_core]
link mlx5_1/1 lqpn 2224 type UD state RTS sq-psn 0 comm [ib_core]
link rxe_foo0/1 lqpn 1 type GSI state RTS sq-psn 0 comm [ib_core]
[root@stevo1 iproute2]# ./rdma/rdma res show qp  lqpn 2224
Invalid argument
No such file or directory
Invalid argument
link mlx5_1/1 lqpn 2224 type UD state RTS sq-psn 0 comm [ib_core]
Invalid argument
No such file or directory
[root@stevo1 iproute2]#


Steve.