On Thu, 2017-06-08 at 23:45 +0200, Arnd Bergmann wrote: > On Thu, Jun 8, 2017 at 11:25 PM, Andy Shevchenko > <andy.shevchenko@xxxxxxxxx> wrote: > > On Thu, Jun 8, 2017 at 11:42 PM, Rasmus Villemoes > > <linux@xxxxxxxxxxxxxxxxxx> wrote: > > > On Thu, Jun 08 2017, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> > > > wrote: > > > > On Thu, Jun 8, 2017 at 9:41 PM, Alexandre Belloni > > > > <alexandre.belloni@xxxxxxxxxxxxxxxxxx> wrote: > > > > > On 08/06/2017 at 20:57:05 +0300, Andy Shevchenko wrote: > > > > > > On Thu, Jun 8, 2017 at 6:05 PM, Alexandre Belloni > > > > > > <alexandre.belloni@xxxxxxxxxxxxxxxxxx> wrote: > > > > Yeah, but the problem is to pass the reference. All dances > > > > around will > > > > uglify the code. > > > > (Obviously we can't pass timespec64/time64_t or anything longer > > > > than > > > > 32 bits as is in %p extension) > > > I like that this gets rid of some mm/dd/yy and other more or less > > > random > > > format and ends up standardizing yyyy-mm-dd HH:MM:SS. However, I > > > do > > > think %pt should take either ktime_t or timespec64 (obviously by > > > reference), > > > > I will try to look in this direction. > > sounds good. > > > > Please don't give people the option of eliding either the time or > > > the > > > date; I've spent too much time dealing with syslog files that > > > don't > > > include the year in the timestamps. > > > > I understand that, but see above. > > When we pretty-print a ktime_t, we probably want to leave out the high > fields as well, as this often refers to a time interval, e.g. a few > seconds. > Even for absolute values, the start of ktime_t is usually not the 1970 > epoch but system boot, so we may not necessarily want the higher > fields. I hoped to find some inspiration in the 'date' man page, which > contains a lot of formatting options, but it's hard to translate that > into > a useful format string within the constraints of %p flags in printk. Rasmus et al., Summarizing this discussion I would go forward with the following - add one more letter in the format to provide argument type (timespec, ktime, ...) - make a config option to enable / disable this facility and select it by users (and/or make it visible for configuration?) - still leave possibility to print either date or time or both - add suffix to print nanoseconds in cases where input has them (and output is not just plain date) - address other (technical) comments -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Intel Finland Oy
