simpleprofile

simpleprofile is a JVMTI agent that lets one get simple JSON profiles with JVMTI

Usage

Build

m libsimpleprofile # or ‘m libsimpleprofiled’ with debugging checks enabled

For binaries with NDK shared libraries only.

m libsimpleprofiled # or m libsimpleprofileds with debugging checks enabled.

The libraries will be built for 32-bit, 64-bit, host and target. Below examples assume you want to use the 64-bit version.

Command Line

The agent is loaded using -agentpath like normal. It takes arguments in the following format:

`file-output[,dump_on_shutdown][,dump_on_main_stop]`

ART

art -Xplugin:$ANDROID_HOST_OUT/lib64/libopenjdkjvmti.so '-agentpath:libsimpleprofiled.so=/proc/self/fd/2,dump_on_main_stop' -cp tmp/java/helloworld.dex -Xint helloworld

• -Xplugin and -agentpath need to be used, otherwise the agent will fail during init.
• If using libartd.so, make sure to use the debug version of jvmti.

Device

% adb root
% adb shell setenforce 0
% adb push $OUT/system/lib64/libsimpleprofileds.so /data/local/tmp/libsimpleprofileds.so
% adb shell
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

RI

java '-agentpath:libsimpleprofiled.so=/proc/self/fd/2,dump_on_main_stop' -cp tmp/helloworld/classes helloworld

Output

A normal run will look something like this:

% ./test/run-test --64 --host --dev --with-agent $ANDROID_HOST_OUT/lib64/libsimpleprofiled.so=dump_on_main_stop,/proc/self/fd/1 001-HelloWorld
<normal output removed>
Hello, world!
...
{"class_name":"Ljava/util/HashMap$KeySet;","method_name":"iterator","method_descriptor":"()Ljava/util/Iterator;","count":6},
{"class_name":"Ljava/util/HashMap$KeyIterator;","method_name":"<init>","method_descriptor":"(Ljava/util/HashMap;)V","count":6},
{"class_name":"Ljava/util/HashMap$HashIterator;","method_name":"<init>","method_descriptor":"(Ljava/util/HashMap;)V","count":6},
{"class_name":"Ljava/lang/String;","method_name":"equals","method_descriptor":"(Ljava/lang/Object;)Z","count":128},
{"class_name":"Ljava/util/Collections$UnmodifiableCollection$1;","method_name":"next","method_descriptor":"()Ljava/lang/Object;","count":38},
{"class_name":"Ljava/util/HashMap$KeyIterator;","method_name":"next","method_descriptor":"()Ljava/lang/Object;","count":38},
{"class_name":"Lsun/misc/Cleaner;","method_name":"add","method_descriptor":"(Lsun/misc/Cleaner;)Lsun/misc/Cleaner;","count":1},
...