There were following problems discovered for tst-timerfd test:
1. Do not set the struct itimerspec's it_interval tv_sec to 2 seconds.
After this change the timerfd will trigger only once (the it_value is
only set in this case).
2. The 'val1' variable (including the call to timerfd_gettime) is not
needed anymore, as it is just enough to read the struct itimerspec
after sleep. As a consequence the 'val2' has been renamed to 'val'.
3. After calling timerfd_gettime, the value of struct itimerspec time,
when timer is running, is the remaining time. In the case of this test
it would be less than 1 second.
As a result the TEST_COMPARE macro logic had to be adjusted.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This change adds new test to assess functionality of timerfd_*
functions.
It creates new timer (operates on its file descriptor) and checks
if time before and after sleep is between expected values.
