perf sched latency: Auto-scale latency and runtime display units

Currently, 'perf sched latency' displays task runtime and delay values
exclusively in milliseconds (ms). This can be hard to read when
latencies are very small (in the microsecond or nanosecond range) or
unusually large (seconds).

Introduce auto-scaling for latency and runtime display columns. Values
are dynamically scaled and output with the most appropriate unit:
nanoseconds (ns), microseconds (us), milliseconds (ms), or seconds (s).

Additionally, rename column headers from "Runtime ms", "Avg delay ms",
and "Max delay ms" to "Runtime", "Avg delay", and "Max delay"
respectively, adjust spacing to maintain column alignment and stripe
redundant prefix strings from each row's format string to produce a
clean, tabular output.

For illustrative purposes, a comparison of the latency table header
before and after this change is shown below:

Before:
 -------------------------------------------------------------------------------------------------------------------------------------------
  Task                  |   Runtime ms  |  Count   | Avg delay ms    | Max delay ms    | Max delay start           | Max delay end          |
 -------------------------------------------------------------------------------------------------------------------------------------------
  kworker/2:2-mm_:154757 |      0.033 ms |        1 | avg:   0.829 ms | max:   0.829 ms | max start: 169486.543205 s | max end: 169486.544034 s

After:
 ------------------------------------------------------------------------------------------------------------------------------------------
  Task                    |    Runtime     |  Count   |    Avg delay    |    Max delay    |      Max delay start  |     Max delay end     |
 ------------------------------------------------------------------------------------------------------------------------------------------
  kworker/2:2-mm_:154757  |      32.873 us |        1 |      829.347 us |      829.347 us |       169486.543205 s |       169486.544034 s |

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>

0 files changed, 0 insertions, 0 deletions