遠程調試步驟
在Android設備上啟動gdbserver並attach你想調試的進程，並指定監聽調試命令的端口（此端口是TV上的端口)
$ adb shell
# ps |grep media #查看要調試進程的PID,以mediaserver進程為例
# gdbserver :1234 --attach 96 #:1234是端口號，96 是進程ID
如果設備上沒有gdbserver,可以由google ndk中獲取，在ndk的如下目錄可以找到這個文件：
android-ndk-r8/toolchains/arm-linux-androideabi-4.9/prebuilt/android-arm
可以將此文件先推送到設備上。
進入源碼服務器，比如5520編譯服務器地址10.9.44.42
進入到源碼工程目錄下，進行環境配置，執行build文件夾下的envsetup.sh和choosecombo xx xx xx 命令，這時就可以使用gdbclient了。
adb connect 電視，成功后執行端口映射，將pc機的1234端口映射到電視1234端口
$ adb forward tcp:1234 tcp:1234 #端口映射，將pc機的1234端口映射到電視的1234端口
$ 在pc端的源碼根目錄下，執行 gdbclient -e mediaserver -p 1234 #從1234端口調試mediaserver
$ target remote:1234
接下來通過file命令來加載將要調試的可執行文件，對於android application來說，均為 out/target/product/generic/symbols/system/bin/app_process 這個文件，及設置搜索solib的搜索路徑。
$file /home/luckychou/share/workspace/MT5520_DEV_Q3/release/android/l-pdk/out/target/product/mt5520_ll/symbols/system/bin/app_process32
$ set solib-search-path /home/luckychou/share/workspace/MT5520_DEV_Q3/release/android/l-pdk/out/target/product/mt5520_ll/symbols/system/lib
$ set solib-absolute-prefix /home/luckychou/share/workspace/MT5520_DEV_Q3/release/android/l-pdk/out/target/product/mt5520_ll/symbols/system/lib
之后，即可如調試PC端的C/C++ code一樣，下斷點，執行，查看內存內容，查看back trace等，來進行對library的debug工作：
If the program you’re backtracing is multi-threaded, you might want to get a backtrace for all threads:
(gdb) thread apply all bt
Another thing which is quite helpful to report is what variables were set locally at each point in the stack:
(gdb) bt full
You might want to report the output of the combination of the preceding options:
(gdb) thread apply all bt full
And if this is too much irrelevant output, you might want to keep only a few calls, such as the top 10:
(gdb) thread apply all bt full 10
If you have a large backtrace, you can log gdb output to a file (the default is gdb.txt):
(gdb) set logging on
(gdb) set logging file myfile.txt
還有很多其他gdb有用的命令，可以參考下網上的。