tree a5d0090945c0ed07a21bb5624f84dff0b5cd7d1a
parent 267832d6bb0d75ce945e623cd1696dde21ee2f2a
author Alex Light <allight@google.com> 1598406543 -0700
committer Alex Light <allight@google.com> 1599152797 +0000

Add a simple profiling agent.

This agent will simply hold onto how many times each method is called
and dump the information in a JSON file wherever one wishes.

Test: manual, attach to google-maps
Test: ./art/test/run-test --host --dev --64 --with-agent $ANDROID_HOST_OUT/lib64/libsimpleprofileds.so=/proc/self/fd/2,dump_on_shutdown 001-HelloWorld
Test: ```
% adb root
% adb shell setenforce 0
% adb push $OUT/system/lib64/libsimpleprofileds.so /data/local/tmp/libsimpleprofileds.so
% adb shell
blueline:/ # cd /data/data/com.google.android.apps.maps
blueline:/data/data/com.google.android.apps.maps # cp /data/local/tmp/libsimpleprofileds.so .
blueline:/data/data/com.google.android.apps.maps # ps -A | grep maps
u0_a178        9143    927 15691440 190132 SyS_epoll_wait     0 S com.google.android.apps.maps
blueline:/data/data/com.google.android.apps.maps # cmd activity attach-agent com.google.android.apps.maps $PWD/libsimpleprofileds.so=$PWD/maps.json
blueline:/data/data/com.google.android.apps.maps # # Do things on the app.
blueline:/data/data/com.google.android.apps.maps # kill -3 9143
blueline:/data/data/com.google.android.apps.maps # wc -l maps.json
17901 maps.json
blueline:/data/data/com.google.android.apps.maps # ^D
% adb pull /data/data/com.google.android.apps.maps/maps.json
% jq 'sort_by(.count) | reverse' maps.json | head -13
[
  {
    "class_name": "Ljava/lang/String;",
    "method_name": "charAt",
    "method_descriptor": "(I)C",
    "count": 586996
  },
  {
    "class_name": "Ljava/lang/Object;",
    "method_name": "<init>",
    "method_descriptor": "()V",
    "count": 482491
  },
```

Change-Id: I87056f641648c496c63c9de715951b65707844ef