Bug ID: JDK-8241439 jdk.NativeLibraryEvent hooks all opened regular files

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JDK 15
15 b27Fixed

https://mail.openjdk.java.net/pipermail/hotspot-jfr-dev/2020-March/001302.html

We would get multiple jdk.NativeLibrary events from 1 library as below:

```
jdk.NativeLibrary {
   startTime = 16:59:06.621
   name = "/usr/lib64/libc-2.30.so"
   baseAddress = 0x7FDB06ACC000
   topAddress = 0x7FDB06AF1000
}

jdk.NativeLibrary {
   startTime = 16:59:06.621
   name = "/usr/lib64/libc-2.30.so"
   baseAddress = 0x7FDB06AF1000
   topAddress = 0x7FDB06C40000
}

    :

```

In addition, we would get the events even if they are not shared library as below:

```
jdk.NativeLibrary {
   startTime = 16:59:06.621
   name = "/home/ysuenaga/OpenJDK/jdk/build/linux-x86_64-server-fastdebug/images/jdk/lib/server/cl
asses.jsa"
   baseAddress = 0x800000000
   topAddress = 0x800007000
}
```

os::get_loaded_modules_info() has introduced in JDK-8056242, and it says this function is for dll/so/dylibs.
In fact, os::get_loaded_modules_info() uses EnumProcessModules() in Windows.

We should merge same library to one event, and should not hook regular files (not shared library).

URL: https://hg.openjdk.java.net/jdk/jdk/rev/b10be698fbaa User: ysuenaga Date: 2020-06-08 08:21:46 +0000

08-06-2020

Suggested fix: http://hg.openjdk.java.net/jdk/submit/rev/873cb61ba446 We can use dl_iterate_phdr(3) to fix this issue instead of /proc/<PID>/maps. It affects for JFR NativeLibrary event on Linux only.

26-05-2020

Relates :	JDK-8056242 - Add function to return structured information about loaded libraries.
Relates :	JDK-8240360 - NativeLibraryEvent has wrong library name on Linux