1. 04 Feb, 2019 1 commit
    • Philippe Gerum's avatar
      testsuite/smokey: posix_clock: prevent false positive in time-dependent test · 99348f65
      Philippe Gerum authored and Jan Kiszka's avatar Jan Kiszka committed
      
      
      clock_decrease_after_periodic_timer_first_tick checks that periodic
      interval timers based on CLOCK_REALTIME are not (pathologically)
      affected by the epoch going backwards.
      
      To this end, we measure the actual time observed between two ticks of
      a periodic timer based on CLOCK_REALTIME with a call to
      clock_settime() injecting a negative offset in between, equivalent to
      five ticks.
      
      Due to processing delays induced by clock_settime() and other latency,
      we could observe a duration which exceeds a tick by a few tenths of
      microseconds. Since we can't anticipate the amount of latency
      involved, let's accept a longer delay of at most two ticks.
      
      This is still correct from the standpoint of the test, which verifies
      that no correlation exists between the clock offset injected by
      clock_settime() and the delay until the next tick generated by the
      affected clock.
      Signed-off-by: Philippe Gerum's avatarPhilippe Gerum <rpm@xenomai.org>
      Signed-off-by: Jan Kiszka's avatarJan Kiszka <jan.kiszka@siemens.com>
      99348f65
  2. 20 Jun, 2015 2 commits