From: Dave Taht <dave.t...@gmail.com> 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. Signed-off-by: Yousuk Seung <ysse...@google.com> Signed-off-by: Dave Taht <dave.t...@gmail.com> Signed-off-by: Neal Cardwell <ncardw...@google.com> --- tc/tc_core.h | 4 ++++ tc/tc_util.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++ tc/tc_util.h | 3 +++ 3 files changed, 62 insertions(+) diff --git a/tc/tc_core.h b/tc/tc_core.h index 1dfa9a4f773b..a0fe0923d171 100644 --- a/tc/tc_core.h +++ b/tc/tc_core.h @@ -7,6 +7,10 @@ #define TIME_UNITS_PER_SEC 1000000 +#define NSEC_PER_USEC 1000 +#define NSEC_PER_MSEC 1000000 +#define NSEC_PER_SEC 1000000000LL + enum link_layer { LINKLAYER_UNSPEC, LINKLAYER_ETHERNET, diff --git a/tc/tc_util.c b/tc/tc_util.c index d7578528a31b..c39c9046dcae 100644 --- a/tc/tc_util.c +++ b/tc/tc_util.c @@ -385,6 +385,61 @@ char *sprint_ticks(__u32 ticks, char *buf) return sprint_time(tc_core_tick2time(ticks), buf); } +/* 64 bit times are represented internally in nanoseconds */ +int get_time64(__s64 *time, const char *str) +{ + double nsec; + char *p; + + nsec = strtod(str, &p); + if (p == str) + return -1; + + if (*p) { + if (strcasecmp(p, "s") == 0 || + strcasecmp(p, "sec") == 0 || + strcasecmp(p, "secs") == 0) + nsec *= NSEC_PER_SEC; + else if (strcasecmp(p, "ms") == 0 || + strcasecmp(p, "msec") == 0 || + strcasecmp(p, "msecs") == 0) + nsec *= NSEC_PER_MSEC; + else if (strcasecmp(p, "us") == 0 || + strcasecmp(p, "usec") == 0 || + strcasecmp(p, "usecs") == 0) + nsec *= NSEC_PER_USEC; + else if (strcasecmp(p, "ns") == 0 || + strcasecmp(p, "nsec") == 0 || + strcasecmp(p, "nsecs") == 0) + nsec *= 1; + else + return -1; + } + + *time = nsec; + return 0; +} + +void print_time64(char *buf, int len, __s64 time) +{ + double nsec = time; + + if (time >= NSEC_PER_SEC) + snprintf(buf, len, "%.3fs", nsec/NSEC_PER_SEC); + else if (time >= NSEC_PER_MSEC) + snprintf(buf, len, "%.3fms", nsec/NSEC_PER_MSEC); + else if (time >= NSEC_PER_USEC) + snprintf(buf, len, "%.3fus", nsec/NSEC_PER_USEC); + else + snprintf(buf, len, "%lldns", time); +} + +char *sprint_time64(__s64 time, char *buf) +{ + print_time64(buf, SPRINT_BSIZE-1, time); + return buf; +} + int get_size(unsigned int *size, const char *str) { double sz; diff --git a/tc/tc_util.h b/tc/tc_util.h index 6632c4f9c528..87be951c622d 100644 --- a/tc/tc_util.h +++ b/tc/tc_util.h @@ -82,12 +82,14 @@ int get_percent_rate64(__u64 *rate, const char *str, const char *dev); int get_size(unsigned int *size, const char *str); int get_size_and_cell(unsigned int *size, int *cell_log, char *str); int get_time(unsigned int *time, const char *str); +int get_time64(__s64 *time, const char *str); int get_linklayer(unsigned int *val, const char *arg); void print_rate(char *buf, int len, __u64 rate); void print_size(char *buf, int len, __u32 size); void print_qdisc_handle(char *buf, int len, __u32 h); void print_time(char *buf, int len, __u32 time); +void print_time64(char *buf, int len, __s64 time); void print_linklayer(char *buf, int len, unsigned int linklayer); void print_devname(enum output_type type, int ifindex); @@ -96,6 +98,7 @@ char *sprint_size(__u32 size, char *buf); char *sprint_qdisc_handle(__u32 h, char *buf); char *sprint_tc_classid(__u32 h, char *buf); char *sprint_time(__u32 time, char *buf); +char *sprint_time64(__s64 time, char *buf); char *sprint_ticks(__u32 ticks, char *buf); char *sprint_linklayer(unsigned int linklayer, char *buf); -- 2.18.0.597.ga71716f1ad-goog