Using a 32 bit field to represent time in nanoseconds results in a
maximum value of about 4.3 seconds, which is well below many observed
delays in WiFi and LTE, and barely in the ballpark for a trip past the
Earth's moon, Luna.
Using 64 bit time fields in nanoseconds allows us to simulate
network diameters of several hundred light-years. However, only
conversions to and from ns, us, ms, and seconds are provided.
The iproute2 64 bit api uses signed values for time. Being able to
represent positive or negative time allows us to calculate +/- deltas
between, for example, the CLOCK_TAI and CLOCK_REALTIME clocks.
Time related utility functions in tc_util.c are moved to lib/utils.c.
Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
[IPROUTE]: Replace "usec" by "time" in function names
Rename functions containing "usec" since they don't necessarily return
usec units anymore.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
[IPROUTE]: Introduce TIME_UNITS_PER_SEC to represent internal clock resolution
Introduce TIME_UNITS_PER_SEC and conversion functions between internal
resolution and resolution expected by the kernel (currently implemented as
NOPs, only needed by HFSC, which currently always uses microseconds).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
