Re: [PATCHv2-next 3/3] serial_core: Remove unused member in uart_port

Dmitry Safonov
2020-01-14T17:47:46Z

On 1/14/20 5:36 PM, Joe Perches wrote:
> On Tue, 2020-01-14 at 17:19 +0000, Dmitry Safonov wrote:
>> It should remove the align-padding before @name.
> []
>> diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
> []
>> @@ -247,7 +247,6 @@ struct uart_port {
>>
>> unsigned char hub6; /* this should be in the 8250 driver */
>> unsigned char suspended;
>> - unsigned char unused;
>
> I suggest this not be applied as this is just to let
> readers know that there is an unused 1 byte alignment
> hole here that could be used for something else.

Heh, 2/3 adds another `unsigned char`, so the neighbours look like:

: unsigned long sysrq; /* sysrq timeout */
: unsigned int sysrq_ch; /* char for sysrq */
: unsigned char has_sysrq;
: unsigned char sysrq_seq; /* index in sysrq_toggle_seq */
:
: unsigned char hub6; /* this should be in the 8250 driver */
: unsigned char suspended;
: unsigned char unused;
: const char *name; /* port name */

So the hole became 4 bytes on 64-bit.

I can make it unused[4], but..

Separated the patch per Greg's review and I think it makes sense to have
it separately from 2/3 because last time I've touched it, it actually
was in use by drivers (regardless the name).

Thanks,
Dmitry