Re: [PATCH 1/2] RDMA/rxe: add missing newline to rxe_set_mtu message

[Zhijian Li (Fujitsu)]

On 23/08/2023 14:35, Zhu Yanjun wrote:
> On Wed, Aug 23, 2023 at 2:25 PM Zhijian Li (Fujitsu)
> <lizhijian@xxxxxxxxxxx> wrote:
>>
>>
>>
>> On 23/08/2023 14:12, Zhu Yanjun wrote:
>>> 在 2023/8/23 10:13, Li Zhijian 写道:
>>>> A newline help flushing message out.
>>>
>>> rxe_info_dev will finally call printk to output information.
>>>
>>> In this link https://github.com/torvalds/linux/blob/master/Documentation/core-api/printk-basics.rst,
>>> "
>>> All printk() messages are printed to the kernel log buffer, which is a ring buffer exported to userspace through /dev/kmsg. The usual way to read it is using dmesg.
>>> "
>>> Do you mean that a new line will help the kernel log buffer flush message out?
>>
>> Yeah, the message will be buffered until it is full or it meets a newline.
> 
> Add PRINTK reviewers:
> 
> Petr Mladek <pmladek@xxxxxxxx>
> Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
> Steven Rostedt <rostedt@xxxxxxxxxxx>
>   John Ogness <john.ogness@xxxxxxxxxxxxx>
> 
> This is about printk. They can decide this commit.

I don't think it's a printk stuff.

In general, when developers add some printk()/pr_info() to print some message in the kernel, they expect this message will be printed in time.
So most of the printk()/pr_info() calls in current kernel accompany a '\n' at the end.

And printk() will also print message to 'console' by default, console could be a serial port(ttyS0) or tty1 etc.

Thanks
Zhijian


> 
> Zhu Yanjun
> 
>>
>>
>>
>>>
>>> Zhu Yanjun
>>>>
>>>> Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
>>>> ---
>>>>    drivers/infiniband/sw/rxe/rxe.c | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
>>>> index 54c723a6edda..cb2c0d54aae1 100644
>>>> --- a/drivers/infiniband/sw/rxe/rxe.c
>>>> +++ b/drivers/infiniband/sw/rxe/rxe.c
>>>> @@ -161,7 +161,7 @@ void rxe_set_mtu(struct rxe_dev *rxe, unsigned int ndev_mtu)
>>>>        port->attr.active_mtu = mtu;
>>>>        port->mtu_cap = ib_mtu_enum_to_int(mtu);
>>>> -    rxe_info_dev(rxe, "Set mtu to %d", port->mtu_cap);
>>>> +    rxe_info_dev(rxe, "Set mtu to %d\n", port->mtu_cap);
>>>>    }
>>>>    /* called by ifc layer to create new rxe device.
>>>