Report units in custom JFR NMT events

[roberttoyonaga]

Summary

This is a small change to add the @DataAmount annotation to jdk.NativeMemoryUsagePeak and NativeMemoryUsageTotalPeakEvent events. This will allow them to report units with the memory size fields similar to jdk.NativeMemoryUsage and jdk.NativeMemoryUsageTotal.

---

Before change:

$jfr print --events jdk.NativeMemoryUsagePeak recording.jfr 

jdk.NativeMemoryUsagePeak {
  startTime = 15:47:35.221 (2024-04-25)
  type = "Threading"
  peakReserved = 424
  peakCommitted = 424
  countAtPeak = 4
  eventThread = "JFR Shutdown Hook" (javaThreadId = 64)
}

jdk.NativeMemoryUsagePeak {
  startTime = 15:47:35.221 (2024-04-25)
  type = "Unsafe"
  peakReserved = 14336
  peakCommitted = 14336
  countAtPeak = 2
  eventThread = "JFR Shutdown Hook" (javaThreadId = 64)
}
...

After change:

jdk.NativeMemoryUsagePeak {
  startTime = 13:18:50.605 (2024-04-30)
  type = "Threading"
  peakReserved = 424 bytes
  peakCommitted = 424 bytes
  countAtPeak = 4
  eventThread = "JFR Shutdown Hook" (javaThreadId = 63)
}

jdk.NativeMemoryUsagePeak {
  startTime = 13:18:50.605 (2024-04-30)
  type = "Unsafe"
  peakReserved = 14.0 kB
  peakCommitted = 14.0 kB
  countAtPeak = 2
  eventThread = "JFR Shutdown Hook" (javaThreadId = 63)
}
...