Android Debugging
From OMAPpedia
There are many different ways of debugging various parts of the Android software stack (ie: bootloader, kernel, applications etc.). We will cover a few tools that we have used. Please feel free to update this list or provide more information about other methods that may be available.
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[edit] Eclipse ADT
[edit] Note on Installing Eclipse Plugins
Before installing the Android Development Tools, be sure to put your proxy server (if applicable) into the General preferences under Network Connections and to "install" the software update link to the version of Eclipse you have (3.5 is "http://download.eclipse.org/releases/galileo/).
You will likely have to install several required plugins from Eclipse before ADT will install (possibly GEF and WST plugins).
[edit] Debugging on Zoom2 with Eclipse ADT
The Android Development Tools (ADT) plugin for Eclipse adds powerful extensions to the Eclipse integrated development environment. It allows you to create and debug Android applications easier and faster. Details on ADT can be obtained from http://developer.android.com/guide/developing/eclipse-adt.html.
It is assumed that ADT plugin has already been setup to work with Eclipse environment as described http://developer.android.com/sdk/1.1_r1/installing.html#installingplugin.
Step 1: Upon installing the ADT plugin for eclipse, Dalvik Debug Monitor Service (DDMS) should have been setup. DDMS configuration should be changed as in below:
Click on Window->Preferences; Select Android -> DDMS Change - ADB debugger base port: 8700; Logging Level: Verbose Click on Apply
Step 2: DDMS perspective can now be opened from the eclipse menu via:
Window -> Open Perspective -> Other -> DDMS; Click on OK
Step 3: Get Eclipse to attach to your Zoom2 board.
Bootup the zoom2 board and find the IP address of the board. If you havent added ip=dhcp in the bootargs, you can start the ethernet and obtain an IP address using dhcp using following commands
# netcfg eth0 up # netcfg eth0 dhcp
Using the command below you can verify that the board did obtain an IP address
# netcfg
NOTE: If you boot via NFS, then uboot will typically print out the board's IP address to console.
On the host machine run the following commands from terminal shell:
$ export ADBHOST=<IP_ADDRESS_OF_YOUR_ZOOM2_BOARD> $ adb kill-server $ adb start-server
Check if you are now connected to the Zoom2 device by running the following command on the Host Terminal console:
$ adb devices
It should output something like:
emulator-5554 device
This confirms that Zoom2 board is connected. With this setup, you should be able to use Android Debug Bridge, Logcat, DDMS and other tools directly from Eclipse ADT environment for creating your applications for Android on Zoom2.
[edit] Troubleshooting
Issue: ADB is not in the path, where should I find it?
Resolution: ADB command line tool is found at: <MYDROID_PATH>/out/host/linux-x86/bin/
Issue: ADB is having a problem connecting over Ethernet.
Resolution: This is because the ADB stub on target defaults to USB. To fix this, in the Zoom console:
# setprop service.adb.tcp.port 5555
This will avoid ADBD defaulting to USB transport. Restart ADBD on Zoom to take the changed settings.
# stop adbd
# start adbd
Alternatively, the setprop command can be included in init.rc so that system property is set at start up, before starting ADB stub.
[edit] Debugging with GDB and DDD
The user space programs can be debugged using various debug commands). Here are some gnu apps that can be used to ease the debugging of binary files on the android platform. GDB, allows you to see what is going on `inside' another program while it executes -- or what another program was doing at the moment it crashed.
[edit] GDB (the GNU Debugger)
Following are the instructions to enable GDB on Android:
1. Obtain the IP address of the target. This can be found by adding “ip=dhcp” in the bootargs, which will obtain and print the IP automatically during boot. Alternatively if you have the busybox command line tools available on the target you can type "ifconfig eth0" to obtain the IP address of the target.
2. On the host, perform the following (once per new console window): Go to mydroid directory and run
source build/envsetup.sh
setpaths
export ADBHOST=<ip addr of target obtained above>
Ensure that above setup works by running
adb kill-server ; adb shell
You should see a command prompt of the target on your host. Verify this by running "ps" or similar commands. Exit the adb shell by typing “exit”
3. Start GDB using the following command
gdbclient <executable name> <port number> <task name>
executable name: file name in system/bin dir
port number: default is :5039 (need the colon before the number)
task name: obtained by running "ps" on the target. GDB uses it to identify the PID internally.
E.g. for video playback, use (note the space after mediaserver and colon):
gdbclient mediaserver :5039 mediaserver
Then you can run commands like “info threads”, “break”, “step” etc.
For a full listing of GDB commands refer to: http://www.yolinux.com/TUTORIALS/GDB-Commands.html
You may have to run the following after each target reboot:
adb kill-server
[edit] DDD (Data Display Debugger)
DDD is a graphical front-end for GDB and other command-line debuggers like GDB.
Following are the instructions to enable DDD on Android:
The steps are almost same as GDB:
1. Obtain the IP address of the target. This can be found by adding "ip=dhcp" in the bootargs, which will obtain and print the IP automatically during boot. Alternatively if you have the busybox command line tools available on the target you can type "ifconfig eth0" to obtain the IP address of the target.
2. Install DDD: in the shell run:
sudo apt-get install ddd
3. Add the following function to build/envsetup.sh:
function dddclient()
{
local OUT_ROOT=$(get_abs_build_var PRODUCT_OUT)
local OUT_SYMBOLS=$(get_abs_build_var TARGET_OUT_UNSTRIPPED)
local OUT_SO_SYMBOLS=$(get_abs_build_var TARGET_OUT_SHARED_LIBRARIES_UNSTRIPPED)
local OUT_EXE_SYMBOLS=$(get_abs_build_var TARGET_OUT_EXECUTABLES_UNSTRIPPED)
local PREBUILTS=$(get_abs_build_var ANDROID_PREBUILTS)
if [ "$OUT_ROOT" -a "$PREBUILTS" ]; then
local EXE="$1"
if [ "$EXE" ] ; then
EXE=$1
else
EXE="app_process"
fi
local PORT="$2"
if [ "$PORT" ] ; then
PORT=$2
else
PORT=":5039"
fi
local PID
local PROG="$3"
if [ "$PROG" ] ; then
PID=`pid $3`
adb forward "tcp$PORT" "tcp$PORT"
adb shell gdbserver $PORT --attach $PID &
sleep 2
else
echo ""
echo "If you haven't done so already, do this first on the device:"
echo " gdbserver $PORT /system/bin/$EXE"
echo " or"
echo " gdbserver $PORT --attach $PID"
echo ""
fi
echo >|"$OUT_ROOT/gdbclient.cmds" "set solib-absolute-prefix $OUT_SYMBOLS"
echo >>"$OUT_ROOT/gdbclient.cmds" "set solib-search-path $OUT_SO_SYMBOLS"
echo >>"$OUT_ROOT/gdbclient.cmds" "target remote $PORT"
echo >>"$OUT_ROOT/gdbclient.cmds" ""
ddd --debugger arm-eabi-gdb -x "$OUT_ROOT/gdbclient.cmds" "$OUT_EXE_SYMBOLS/$EXE"
else
echo "Unable to determine build system output dir."
fi
}
4. On the host, perform the following (once per new console window): Go to mydroid directory and run
source build/envsetup.sh
setpaths
export ADBHOST=<ip addr of target obtained above>
Ensure that above setup works by running
adb kill-server ; adb shell
You should see a command prompt of the target on your host. Verify this by running "ps" or similar commands. Exit the adb shell by typing “exit”
5. Start DDD using the following command
dddclient <executable name> <port number> <task name>
executable name: file name in system/bin dir
port number: default is :5039 (need the colon before the number)
task name: obtained by running "ps" on the target. GDB uses it to identify the PID internally.
E.g. for video playback, use (note the space after mediaserver and colon):
dddclient mediaserver :5039 mediaserver
For the DDD manual, refer to: http://www.gnu.org/manual/ddd/html_mono/ddd.html
You may have to run the following after each target reboot:
adb kill-server
[edit] Lauterbach TRACE32
Lauterbach TRACE32 could be used to debug bootloaders, kernel and user space.
Instructions on using Lauterbach TRACE32 for debugging on Zoom2:
Install Lauterbach TRACE32 software on your PC (the below screenshot is from Oct 10 2008 release). Connect emulator cable to J5 (20 pin header) on Zoom2 debug board and power the emulator. Connect USB cable from the emulator to PC
Run zoom2_startup.cmm script to select your target as OMAP3430 and attach from File -> Run Batchfile. If the script is not run, some of the settings will have to be manually selected from CPU -> System Settings
Ensure that the emulator is “running” by the green status indicator (seen at the bottom of the below screenshot) before exercising any use cases that need to be debugged.
Run the use case (ex: audio/video playback) Halt the processor by clicking on the “pause” button and view registers (View -> Registers), list source (View -> List Source) etc.
Make sure to load the symbols for files that you’re interested in debugging and set source path for source code correlation to work correctly. Also you may have to ensure that options such as –g is added during compiling your code to generate symbolic debugging directives. In some instances consider reducing the level of optimization used as the compiler will re-arrange instructions and hence it may be difficult to match the order of execution in the source code.
Examples of setting the source search path and loading symbols:
sYmbol.SourcePATH.Set "V:\mydroid\kernel\"
data.load.elf V:\mydroid\kernel\vmlinux /nocode /strippart "kernel"
These commands can be directly entered from either the debugger command prompt or by using a *.cmm script.
Adapt changed base directories with the "/strippart" option; do not use recursive directory search, due to performance reasons and equal source file names.
For user space debugging, TRACE32 needs some help as it needs to be told where some of the modules you're interested in debugging are loaded. To do this you will have to run "ps" on the target and get PIDs for the application.
Then run "cat /proc/PID/maps > logfile" where PID is the process ID retrieved from "ps" in the above step. There is an avplayback_symbols.cmm file attached that exhibits how to do this. Below screenshot demonstrates being halted in user space during running of an AV playback use case.
zoom2_startup.cmm
avplayback_symbols.cmm
[edit] CodeComposer
This could be used to debug bootloaders. Previous versions of CCS (v3.3 and older) did not contain Linux awareness but it is currently being added to CCSv4. It should be possible to debug the kernel and user space once CCSv4 is released. See Linux_Aware_Debug for more information.
[edit] Selectively Enable Opencore Debug Print
To utilize the existing log statements without rebuilding the whole PV library, you can do this:
1. In the beginning of the file, after the last "#include" line, add following:
- include <utils/Log.h>
- undef LOG_TAG
- define LOG_TAG "YOUR_MODULE_NAME"
- undef PVLOGGER_LOGMSG
- define PVLOGGER_LOGMSG(IL, LOGGER, LEVEL, MESSAGE) JJLOGE MESSAGE
- define JJLOGE(id, ...) LOGE(__VA_ARGS__)
2. In the end of the file, add these:
- undef PVLOGGER_LOGMSG
- define PVLOGGER_LOGMSG(IL, LOGGER, LEVEL, MESSAGE) OSCL_UNUSED_ARG(LOGGER);
You can play with the macro to filter based on level too.
[edit] Profiling
There is a simple profiling mechanism implemented in the kernel, implemented by storing the current instruction pointer at each clock tick.
To enable profiling, pass the boot argument
profile=N
where N is a number which determines the granularity of profiling. The lesser the number, the more the granularity of profiling.
A busybox utility named 'readprofile' is available to process the profiled data. 'readprofile' requires the kernel symbol table file 'System.map' to resolve the symbols.
To clear the profiled data:
$readprofile -r
To display the profiled data:
$readprofile -m /System.map|sort -nr
You should see an output similar to the following:
1415 total 0.0003
1153 omap3_enter_idle 3.3132
28 schedule 0.0304
15 omap_i2c_isr 0.0179
12 v7wbi_flush_user_tlb_range 0.1579
11 copy_page 0.1146
10 __memzero 0.0781
8 __copy_to_user 0.0085
6 update_mmu_cache 0.0341
5 sub_preempt_count 0.0260
5 mmc_queue_map_sg 0.0305
5 handle_IRQ_event 0.0431
4 unmap_vmas 0.0027
4 filemap_fault 0.0038
4 __do_fault 0.0042
3 vsnprintf 0.0013
3 up_read 0.1500
3 omap_hsmmc_enable_clks 0.0069
3 kmem_cache_alloc 0.0208
3 get_page_from_freelist 0.0025
....
The first column gives the number of ticks and the last column gives the number of ticks divided by function size.
This profiler covers only the kernel. For system wide profiling and advanced options, OProfile can be used.
[edit] OProfile
OProfile is a system-wide profiler for Linux systems, capable of profiling all running code at low overhead. It consists of a kernel driver and a daemon for collecting sample data, and several post-profiling tools for turning data into information
OProfile is optional component during KERNEL build. It may have been enabled by default. You can confirm that the kernel has OProfile support, by looking for following lines in the <mydroid_folder>/kernel/.config file
CONFIG_OPROFILE_OMAP_GPTIMER=y
CONFIG_OPROFILE=y
CONFIG_HAVE_OPROFILE=y
Hardware Configuration
The Hardware Configuration required to execute the test cases includes:
Linux machine (can be with your favorite distro)
TCP/IP configuration on Zoom2 board
Zoom2 Board
Software Configuration
The Software Configuration required to execute the test cases includes:
Tera Term (or any terminal program)
Graphviz on Linux machine (Use this command on Host terminal
$ sudo apt-get install graphviz
GPROF2DOT python script (Copy the script to any location in your path (e.g. in ~/bin of your Linux machine);
Ensure that ~/bin is exported in the PATH
Run the following command -
$ cd ~/bin && chmod 777 gprof2dot.py
Installation
This step should be done after the android file system has been built.
$MYDROID is the location where the android SDK is installed. eg: export MYDROID=/home/$user/Lxx.x/mydroid
Edit the $MYDROID/external/oprofile/opimport_pull script as follows:
Remove the python version number from the first line eg. change
#!/usr/bin/python2.4 -E
to
#!/usr/bin/python -E
Append the following lines at the end of the file to generate cpuloads.txt and callgraph.png for further analysis
os.system(oprofile_event_dir + "/bin/opreport --session-dir=. >> cpuloads.txt")
os.system(oprofile_event_dir + "/bin/opreport --session-dir=. -p $OUT/symbols -l -t 0.1 >> cpuloads.txt")
os.system(oprofile_event_dir + "/bin/opreport -cg --session-dir=. -p $OUT/symbols > callgraph.txt")
os.system("cat callgraph.txt | gprof2dot.py -s -w -f oprofile -n 0.1 -e 0.1 | dot -Tpng -o callgraph.png")
On Eclair we have seen the Android tools opannotate, oparchive, opimport and opreport tools in prebuilt/linux-x86/oprofile/bin/ folder are not working properly.
These binaries (tar balled) from donut are available @ Oprofile.tar.gz. Download this .gz file to $MYDROID folder
$ cd $MYDROID
$ tar xvf Oprofile.tar.gz
Since we perform the post-processing on host, we don't need the actual vmlinux file (~40 MB) on target. Make sure that you create a dummy file named "vmlinux" in the root directory to satisfy opcontrol arguments.
# echo 0 > /vmlinux
Execution
Set-up OProfile directories
Make sure that you have created an empty file and named it vmlinux as described in above section. Run the following command on the target
# opcontrol --setup
By default there should be no output.
In case you see, "Cannot create directory /dev/oprofile: File exists do_setup failed#", it means that, OProfile is not built in the Kernel. Verify that you have selected OProfile in make menuconfig step of Kernel build (Refer Configuration Section)
Initialize the OProfile daemon
The kernel range start and end addresses need to be verified on the setup for each release using:
# grep " _text" /proc/kallsyms
c0030000 T _text
# grep " _etext" /proc/kallsyms
c03e1000 A _etext
Note: You need busybox installed for this command to work. Refer here if you haven't set-up busybox.
Using the above addresses, run the following command
# opcontrol --vmlinux=/vmlinux --kernel-range=0xC0030000,0xC03e1000 --event=CPU_CYCLES:64
You should see the following output on your terminal
Cannot open /dev/oprofile/1/enabled: No such file or directory
Cannot open /dev/oprofile/2/enabled: No such file or directory
Using 2.6+ OProfile kernel interface. Reading module info.
Using log file /data/oprofile/samples/oprofiled.log
# init: untracked pid 914 exited
Increase the Back trace depth, so that more details can be captured in the log
# echo 16 > /dev/oprofile/backtrace_depth
To ensure that everything is ready, you can run the following command
# opcontrol --status
The following output should be seen. Note that the PID will change depending on your system.
Driver directory: /dev/oprofile
Session directory: /data/oprofile
Counter 0:
name: CPU_CYCLES
count: 64
Counter 1 disabled
Counter 2 disabled
oprofiled pid: 915 profiler is not running
0 samples received
0 samples lost overflow
Starting and Stopping the profiler
Run the following command to start the profiler
# opcontrol --start
and use the command below to stop the profiler
# opcontrol --stop
Generating the Results
We need to run the following steps on the Host machine (that has android SDK/build) to generate the results.
On command prompt of Host machine (that has android SDK/build), do the following
$ cd $MYDROID
$ source build/envsetup.sh
$ setpaths
$ export ADBHOST=<ip address of ZOOM2 board>
Note: This should be done @ $MYDROID level (where the build was set-up otherwise, it wouldn't work)
If ADB over Ethernet is not working refer to Troubleshooting here
You can use the following commands to start DHCP on Zoom board and set-up ADB over ethernet
# netcfg eth0 up ; sleep 3 ; netcfg eth0 dhcp ; sleep 2 ; netcfg
# setprop service.adb.tcp.port 5555 ; stop adbd ; start adbd
Post-process OProfile results
This needs to be done from the PC where Android SDK is installed. Go to the terminal on host PC and do the following:
If you are using OProfile package with pre-build binaries, symbol files and vmlinux, you can follow the steps below: In case, you are using OPROFILE binaries that were not build on your machine, you might have to create a symbolic link to zoom2 folder, since OProfile looks there
$ mkdir ~/oprofilepackage && cd ~/oprofilepackage
$ tar xvjf <Path_to_Oprofile package>
$ cd mydroid
$ mv ../kernel .
$ source build/envsetup.sh
$ sed -i -e 's_$(call inherit-product, frameworks/base/data/sounds/OriginalAudio.mk)_#$(call inherit-product, frameworks/base/data/sounds/OriginalAudio.mk)_g' build/target/product/full.mk
$ setpaths
$ export MYDROID=${PWD}
$ ln -s $MYDROID/out/target/product/zoom2 $MYDROID/out/target/product/generic
NOTE: The Kernel path needs to be updated for your KERNEL build
$ cp $MYDROID/kernel/android-2.6.32/vmlinux $OUT/symbols/vmlinux
Generate the OPROFILE results using the command below
$ opimport_pull <new_dir_to_store_dump_and_results_on_Linux_machine>
The following files and the Callgraph image can be referred for OProfile results. They will be generated in the <new_dir_to_store_dump_and_results_on_Linux_machine> in step above
Note: If there are some binaries that are compiled on WINDOWS and linked in to your build :( - you will see the message below
Traceback (most recent call last):
File "/home/user/bin/gprof2dot.py", line 1965, in <module>
Main().main()
File "/home/user/bin/gprof2dot.py", line 1890, in main
self.profile = parser.parse()
File "/home/user/bin/gprof2dot.py", line 1062, in parse
self.parse_entry()
File "/home/user/bin/gprof2dot.py", line 1112, in parse_entry
function = self.parse_subentry()
File "/home/user/bin/gprof2dot.py", line 1136, in parse_subentry
filename, lineno = source.split(':')
ValueError: too many values to unpack
cat: write error: Broken pipe
In this case, you can open callgraph.txt in <new_dir_to_store_dump_and_results_on_Linux_machine> in your favourite editor. Search for ":\" and delete the "<any_letter:>" in front of that line.
For eg. if you have E:\workspaces\ make it \workspaces\
Now, cd to <new_dir_to_store_dump_and_results_on_Linux_machine> and run the following command to generate callgraph.png manually
# cd <new_dir_to_store_dump_and_results_on_Linux_machine>
# cat callgraph.txt | gprof2dot.py -s -w -f oprofile -n 0.1 -e 0.1 | dot -Tpng -o callgraph.png
The guidelines and caveats while interpreting Oprofile results are available at Oprofile source forge Wiki
[edit] Strace
Recommended Usage on target
# strace -ff -F -tt -s 200 -o /sqlite_stmt_journals/strace -p <process_id_that_needs_to_be_traced>
Note
-ff makes strace follow fork() and output each forked files trace to a different file
-F means we try and follow any vfork()s.
-tt prints out the time of system calls in microseconds
-s 200 so that we can see a bit more detail in any strings that are used.
[edit] Using INST2 for Performance Measurement on DSP
INST2 is a tool that helps us measure DSP MHz used for a particular use case e.g. Video playback or record.
It is recommended that the VDD1 OPP is locked before starting this tool for obtaining accurate result.
To lock the OPP use the following commands:
# echo n > /sys/power/vdd1_lock
(where n stands for the OPTIMAL OPP the use case should run at)
Refer to this omap3-opp.h file for the OPP table corresponding to your chip
After executing your usecase, make sure that OPP lock is removed using the command below
# echo 0 > /sys/power/vdd1_lock
Step 1: Install busybox on the target filesystem.
Copy the pre-built busybox at /data/busybox/
On target do the following
# cd /data/busybox/ # chmod 777 busybox # busybox --install # export PATH=/data/busybox/:$PATH
Incase the "busybox --install" fails with message "Busybox not found" error, check with ls command to confirm if busybox is actually present and then try "./busybox --install"
PS: This step is optional for FROYO (2.6.32 Kernel)
Step 2: Download the Dsp_load_measurement_tool.tar.gz file to your host machine if you are on eclair (2.6.29 Kernel) or Dsp_load_measurement_tool_froyo.tar.gz for Froyo (2.6.32 Kernel)
Untar this file using the command below
$ tar xvf Dsp_load_measurement_tool.tar.gz $ cd dsp_load_measurement_tool $ tar xvf inst2.tar
Copy /dsp_load_measurement_tool/inst_log file to the root directory in your file system; using SD card or adb push
# cp inst_log .<file system's root>
OR
$ adb push inst_log .
Step 3: Give permissions to the files copied
# cd /
# chmod 777 inst_log
Step 4: Now run the use case i.e. start playback or record
Step 5: Run the instrumentation
# ./inst_log
Following messages should appear
DSP device detected !!
DSPProcessor_Attach succeeded.
Step 6: Once the use case is complete (i.e. playback or record is done), wait for "INST: Log file written. Waiting for INST DSP side cleanup" message
Step 7: Now wait for "INST: DSP Cleanup done. Exiting" message. If this msg does not appear, run the use case once more and wait again for a "INST: DSP Cleanup done. Exiting" message. Basically this will flush previous results and you do not need to run the full use case again.
This is to make sure previous result is flushed out.
Step 8: Bring the "log.bin" on HOST PC. This gets generated in /sqlite* folder of target FS for Eclair (2.6.29 kernel) and in /mnt folder on Froyo (2.6.32 kernel)
Important Note: busybox should be installed prior to executing the cp command. If you get the message "cp: not found" while copying the log, you should use the adb pull command before unmounting the SD card.
For Eclair (2.6.29 kernel)
# cp /sqlite*/*.bin /
# cp log.bin /sdcard OR <adb pull ...>
# sync
For Froyo (2.6.32 kernel)
# cp /mnt/*.bin /
# cp log.bin /sdcard OR <adb pull ...>
# sync
Step 9: On the HOST PC use the following command line to generate the results.
Go to following folder:
$ cd dsp_load_measurement_tool\inst2\tools
$ perl inst_load.pl -c<dsp freq> log.bin
for example
$ perl inst2/tools/inst_load.pl -c660 log.bin
On the screen you will see information about the file for example:
Number of records: 40731 splice() offset past end of array at inst2/tools/inst_load.pl line 123. Range #0 - beg: 0, end: 40731, length: 40731 Range #1 - beg: 0, end: 40731, length: 40731 Ignoring IDLE traces 0-22 and 40714-40730 Clock Freq: 660 MHz Total Cycles: 25383675998 Event | Handle_Event | Cycles | Evts/s | ms/Evt | MHz |30 Evt/s MHz ------+---------------+-----------+---------+--------+-------+------------ unkwn | 00000000_0000 | 11568 | 0 | 0 | 0 | IDLE | 00000000_2001 | 1.396e+10 | 48.99 | 11.23 | 220 | UALG | 2025fad4_2009 | 70257552 | 39 | 0.07 | 1.1 | 0.85 CTRL | 2025fad4_2011 | 40768 | 0.19 | 0.01 | 0 | RESET | 2025fad4_2021 | 762453 | 0.3 | 0.1 | 0 | USN | 2025fad4_2041 | 47083524 | 50.17 | 0.04 | 0.7 | ALGO | 2025fad4_2101 | 560448611 | 19.68 | 1.12 | 8.8 | 13.46 UALG | 20260ee4_2009 | 2.320e+09 | 25.56 | 3.58 | 36.6 | 42.91 CTRL | 20260ee4_2011 | 21475 | 0.13 | 0.01 | 0 | RESET | 20260ee4_2021 | 286269 | 0.05 | 0.24 | 0 | USN | 20260ee4_2041 | 116914279 | 76.21 | 0.06 | 1.8 | ALGO | 20260ee4_2101 | 8.305e+09 | 25.54 | 12.81 | 130.9 | 153.7
Look at the last row, in above results. In this case the algo. consumed 130 Mhz. and it was running @ 25.54 fps. If we interpolate that to 30 fps, the effective Mhz would be 153.7
Step 10: The final step is to apply the next formula:
DSP Mhz consumption = (Clock Freq - IDLE MHz).
For example in this case above the DSP CPU Load is 400-220 = 180 MHz
[edit] Debugging segmentation fault
Type 1 Seg Fault has backtrace of shared objects (most of the times we face this)
The PC holds the offset and it has to be traced in the top most 'so' file present in back trace. This can be done by using addr2line or objdump tool
a. Using addr2line:
Syntax: <path to arm-eabi-addr2line> -f -e <path to so file> <offset which is the PC value>
Example: #00 pc 0000e234 /system/lib/libc.so ./prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/arm-eabi-addr2line -f -e ./out/target/product/generic/symbols/system/lib/libc.so 0x0000e234
Returns strlen bionic/libc/arch-arm/bionic/strlen.c:62
b. Using objdump:
Syntax: <path to arm-eabi-objdump> -S <path to so file>
Example: prebuilt/linux-x86/toolchain/arm-eabi-4.3.1/bin/arm-eabi-objdump -S out/target/product/zoom2/symbols/system/lib/libOMX.TI.Video.encoder.so > ObjDumpFile.txt Output is redirected to ObjDumpFile file
Now the ObjDumpFile has the Intermix of source code with disassembly. We can search using the PC offset in it to see the exact line number
Tip: Make sure to use the debug version of 'so' files which are within the symbols dir in out folder otherwise we would not get the source code symbols in obj dump
Type 2 Seg fault print has the thread name along with register values. The backtrace of shared objects is not present
1. The PC holds a virtual address
2. The first '3' digits of PC provide info on the virtual memory mapping where the shared object('so') is loaded and remaining digits provide the offset within the 'so'
3. Use the 'ps' call to get the Process ID of the thread where it fails.
4. Get the memory map of the process using the following:
In device console/adb shell, print values of 'maps' file within the process id <pid>. Syntax: cat proc/<pid>/maps It is recommended that we get the memory map during the normal execution before the failure itself otherwise it is possible for process to be killed and might lead to mismatch.
5. Use the first '3' digits of PC value to identify the shared object which has caused the failure(using memory map)
6. Get the obj dump of the 'so' and search with the offset to get the exact line of failure. (this can be done in the similar way as in Type 1 seg fault debugging mentioned above)
Example:
Seg Fault Message: PV author: unhandled page fault (11) at 0x00000004, code 0x017 pgd = ccfc8000 [00000004] *pgd=8cbe1031, *pte=00000000, *ppte=00000000 Pid: 9691, comm: PV author CPU: 0 Not tainted (2.6.29-omap1 #20) PC is at 0x81b23140 LR is at 0x81b23049 ...
Based on PC, the shared object is in range of 0x81bxxxxx and offset within that is 0x23140
PV author runs in context of Media server process (PID: 944) Using cat /proc/944/maps we can identify the ‘so’ loaded in this region 81b00000-81b2a000 r-xp 00000000 b3:02 34574 /system/lib/libOMX.TI.Video.encoder.so So appears to be in OMX TI Video encoder
Now with the offset we can use the addr2line or objdump to get the line causing this issue
[edit] OPP Level Measurement
We can measure the OPP level(VDD1) at which the use case is running easily using the script available in Mydroid (FroYo codebase).
Script path: <MYDROID_PATH>/device/ti/support-tools/scripts/measurement/get_opp_levels.sh
Or you can access it from GIT Web interface
Pre-requisite
a. Busybox binary is present in /data/busybox folder (instructions for this can be referred to Step 1 under section "Using INST2 for Performance Measurement on DSP" above
b. Copy this script file(get_opp_levels.sh) to the file system
Steps for measurement: (in device console)
a. Change the permissions of the script file
b. Start the desired use case
c. Execute the script
chmod 777 get_opp_levels.sh <start use case> ./get_opp_levels.sh
d. Output would look like this:
OPP Level,Initial Time(cs),Second Time(cs),Time Spent in OPP(cs),Measurement Time(s),Percentage Time in OPP OPP1G,2332,2332,0,20,0 OPP130,131,131,0,20,0 OPP100,410,410,0,20,0 OPP50,43145,45151,2006,20,100
Based on the percentage time we can decide the OPP at which use case has run. In the above example, it has run at OPP50 for 100% of the time for 20 second window.
Other pointers:
a. The script by default runs for 20secs and prints the results.
b. It can be tweaked based on our requirements to perform it for shorter/longer duration etc. using an additional argument.
For eg: The command below with measure OPP transitions for 100 sec. window
./get_opp_levels.sh 100
