Re: [PATCH v3 4/5] xen/console: Provide timestamps as an offset since boot

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 07/03/14 09:47, Jan Beulich wrote:
>>>> On 06.03.14 at 20:28, Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>> --- a/docs/misc/xen-command-line.markdown
>> +++ b/docs/misc/xen-command-line.markdown
>> @@ -275,11 +275,20 @@ cleared.  This allows a single port to be shared by two 
>> subsystems
>>  makes sense on its own.
>>  
>>  ### console\_timestamps
>> -> `= <boolean>`
>> +> `= none | date | boot`
>>  
>> -> Default: `false`
>> +> Default: `boot`
> I'd prefer the default to remain "no time stamps". They're useful
> occasionally but not generally, and they consume serial console
> bandwidth.

I would disgree with usefulness, but can see your point - I shall revert
the default back to none.

>
>> +static void __init parse_console_timestamps(char *s)
>> +{
>> +    if ( *s == '\0' || /* Compat for old booleanparam() */
>> +         !strcmp(s, "date") )
>> +        opt_con_timestamp_mode = TSM_DATE;
>> +    else if ( !strcmp(s, "boot") )
>> +        opt_con_timestamp_mode = TSM_BOOT;
>> +    else if ( !strcmp(s, "none") )
>> +        opt_con_timestamp_mode = TSM_NONE;
>> +    else
>> +        printk(XENLOG_ERR "Unrecognised timestamp mode '%s'\n", s);
> Printing from command line parsing routines is IIRC rather pointless
> (i.e. ISTR it goes no-where), and in the majority of other cases I
> think we don't warn about improper arguments of options. With
> the command line being logged as a whole, there's also not much
> point since the incorrect value can be easily determined by looking
> there.
>
> Jan
>

It appears at the top of xl dmesg, but not on the serial console.  I
shall drop it.

~Andrew