Re: [PATCH] ALSA: seq_timer: use monotonic times internally

[Takashi Iwai <tiwai@suse.de>]

On Fri, 17 Jun 2016 17:10:32 +0200,
Arnd Bergmann wrote:
> 
> The sequencer client manager reports timestamps in units of unsigned
> 32-bit seconds/nanoseconds, but that does not suffer from the y2038
> overflow because it stores only the delta since the 'last_update'
> time was recorded.
> 
> However, the use of the do_gettimeofday() function is problematic
> and we have to replace it to avoid the overflow on on 32-bit
> architectures.
> 
> This uses 'struct timespec64' to record 'last_update', and changes
> the code to use monotonic timestamps that do not suffer from leap
> seconds and settimeofday updates.
> 
> As a side-effect, the code can now use the timespec64_sub() helper
> and become more readable and also avoid a multiplication to convert
> from microseconds to nanoseconds.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Thanks, applied.  It's even a nice cleanup!


Takashi