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Document related concepts
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Transcript 
JavaME Connected Device
Configure
Development Environment and
Garbage Collector of Virtual Machine
Speaker: Chu, Hua-Rong
Advisor: Chung Yung
OUTLINE
•
•
•
•
CDC implementation overview
Build Sun CDC1.0.1 in Ubuntu
What happens during the build process
Garbage Collector of Sun CVM
2
JavaME CDC
IMPLEMENTATION OVERVIEW
3
CDC platform Survey
• IBM
– WebSphere Everyplace Micro Environment
– Support CDC1.1
– Ref: 劉惠玲, 嵌入式系統裝置走向跨平台的推手 - IBM J9, 2007 IBM developerWorks（~/cdc/CDC doc/IBMJ9.ppt）
• Sun
– Offical CDC
– Mobile & Embedded Community: phoneME Advanced
4
Sun CDC History
Personal Java (1999)
JavaME CDC1.0 (2001)
JavaME CDC1.1 (2005)
phoneME Advanced(2008)
JavaSE for Embedded? (2007)
5
Sun CDC family
• JavaME CDC1.0 (based on JavaSE1.3)
• JavaME CDC1.0.1 (based on JavaSE1.3.1)
• JavaME CDC1.1 (based on JavaSE1.4)
– ARM, PowerPC, MIPS, SPARC, x86 (interpreter only)
– Linux, Solaris, Darwin, Win32
• phoneME Advanced MR2 (2008)
– ARM, x86
– Linux, Windows Mobile, OpenWRT
6
JavaME CDC
BUILD SUN CDC 1.0.1
7
PartI: Source Code
• Source Code:
– j2me_cdcfp-1_0_1-fcs-src-b12-linux-i68614_May_2002.zip
– Download: http://jtrue.pl/files/GPS/
8
PartII: Environment
•
•
•
•
Redhat7.1 / Ubuntu 6.06
JDK1.3 / JDK1.4
egcs6 / gcc3.3 and related C develop tool
ksh
9
PartIII: Troubleshooting
• Problem: This Version's java code is based on
JavaSE 1.3.1.
• Java Compile time error:
../../src/share/classes/java/lang/SecurityManager.java:299: cannot find symbol
symbol : method initCause(java.lang.ClassNotFoundException)
location: class java.lang.NoClassDefFoundError
synchronized(SecurityManager.class) {
^
• JDK6 javac with option -source 1.4/1.3 is no use
• Solution：downgrade to JDK1.4/1.3
10
PartIII: Troubleshooting
• Problem: GCC4 is restricted for nonstandard C
code in this Version.
• C Compile time error:
complie time Error:
Checking for test classes to compile ...
... ../../build/linux-i686/obj/globals.o
../../src/share/javavm/runtime/globals.c:121:1: 錯誤： 粘貼「.」和
「nullClassLoaderLock」不能給出一個有效的預先處理識別字
11
PartIII: Troubleshooting
• Solution：use GCC3.3(gcc -V3.3 if gcc4 is
installed)
change line 117 of /cdcfoundation/src/share/javavm/runtime/globals.c from
#define CVM_SYSMUTEX_ENTRY(mutex, name) {&CVMglobals.##mutex, name}
#define CVM_SYSMUTEX_ENTRY(mutex, name) {&CVMglobals. mutex, name}
12
PartIII: Troubleshooting
• Problem: glibc <2.2 is needed in this Version
• Linking Time Error:
Linking ../../build/linux-i686/bin/cvm
../../build/linux-i686/obj/UNIXProcess_md.o：在函式「sigchld_handler」中
:../../src/linux/native/java/lang/UNIXProcess_md.c:213: 未定義參考到「
__libc_wait」
collect2: ld 回傳 1
make: *** [../../build/linux-i686/bin/cvm] Error 1
13
PartIII: Troubleshooting
• Solution: patch
~/src/linux/native/java/lang/UNIXProcess_md
.c
34,53c34
<
< /* following lines Hacked by Kent Hulick based on
< * ftp://people.redhat.com/drepper/libcwait.c
< * fixes a broken calls to a removed glibc function:*/
< #include
< #include
< pid_t __libc_wait (int *status)
<{
< int res;
< asm volatile ("pushl %%ebx\n\t"
< "movl %2, %%ebx\n\t"
< "movl %1, %%eax\n\t"
< "int $0x80\n\t"
< "popl %%ebx"
< : "=a" (res)
< : "i" (__NR_wait4), "0" (WAIT_ANY), "c" (status), "d" (0),
< "S" (0));
< return res;
<}
<
--
14
PartIV: Preperation&Configure
#sudo su
#cd /usr/local/src
#wget http://jtrue.pl/files/GPS/j2me_cdcfp-1_0_1fcs-src-b12-linux-i686-14_May_2002.zip
#unzip j2me_cdcfp-1_0_1-fcs-src-b12-linux-i68614_May_2002.zip
#unzip cdcfoundation-1_0_1-fcs-src.zip
#cd cdcfoundation/build
15
PartIV: Preperation&Configure
Edit Makefile ./linux/defs.mk :
./linux/defs.mk:#petertc1026
./linux/defs.mk-#CFLAGS_SPEED = -c $(CC_ARCH_FLAGS) $(CCFLAGS) $(CCFLAGS_SPEED) $(CPPFLAGS)
./linux/defs.mk-#CFLAGS_SPACE = -c $(CC_ARCH_FLAGS) $(CCFLAGS) $(CCFLAGS_SPACE) $(CPPFLAGS)
./linux/defs.mk-#SO_CFLAGS = -c $(SO_CC_ARCH_FLAGS) $(CCFLAGS) $(CPPFLAGS)
./linux/defs.mk-CFLAGS_SPEED = -V3.3 -c $(CC_ARCH_FLAGS) $(CCFLAGS) $(CCFLAGS_SPEED) $(CPPFLAGS)
./linux/defs.mk-CFLAGS_SPACE = -V3.3 -c $(CC_ARCH_FLAGS) $(CCFLAGS) $(CCFLAGS_SPACE) $(CPPFLAGS)
./linux/defs.mk-SO_CFLAGS = -V3.3 -c $(SO_CC_ARCH_FLAGS) $(CCFLAGS) $(CPPFLAGS)
16
PartIV: Preperation&Configure
Edit Makefile ./share/defs.mk :
./share/defs.mk:#petertc1026
./share/defs.mk-#CVM_GNU_TOOLS_PATH=/micro/tools/i686-redhat-linux/gnu/bin
./share/defs.mk-CVM_GNU_TOOLS_PATH=/usr/bin
17
PartIV: Preperation&Configure
Patch
/usr/local/src/cdcfoundation/src/share/java
vm/runtime/globals.c:117
//petertc1026
/*#define CVM_SYSMUTEX_ENTRY(mutex, name) {&CVMglobals.##mutex, name}*/
#define CVM_SYSMUTEX_ENTRY(mutex, name) {&CVMglobals. mutex, name}
18
PartIV: Preperation&Configure
Patch
/usr/local/src/cdcfoundation/src/linux/nati
ve/java/lang/UNIXProcess_md.c:213
34,53c34
<
< /* following lines Hacked by Kent Hulick based on
< * ftp://people.redhat.com/drepper/libcwait.c
< * fixes a broken calls to a removed glibc function:*/
< #include <errno.h>
< #include <sys/syscall.h>
< pid_t __libc_wait (int *status)
<{
< int res;
< asm volatile ("pushl %%ebx\n\t"
<
"movl %2, %%ebx\n\t"
<
"movl %1, %%eax\n\t"
<
"int $0x80\n\t"
<
"popl %%ebx"
<
: "=a" (res)
<
: "i" (__NR_wait4), "0" (WAIT_ANY), "c" (status), "d" (0),
<
"S" (0));
< return res;
<}
<
19
PartV: Build
#cd linux-i686
#make CVM_DEBUG=true
JAVABIN=/usr/java/j2sdk1.4.2_18/bin
20
PartVI: Demo
# bin/cvm -Djava.class.path=testclasses.zip HelloWorld
> GC[SS]: Initialized semi-space gen for generational GC
>
Size of *each* semispace in bytes=1048576
>
Limits of generation = [0xb7942200,0xb7b42200)
>
First semispace = [0xb7942200,0xb7a42200)
>
Second semispace = [0xb7a42200,0xb7b42200)
> GC[MC]: Initialized mark-compact gen for generational GC
>
Size of the space in bytes=3145728
>
Limits of generation = [0xb7b42200,0xb7e42200)
> GC[generational]: Auxiliary data structures
>
heapBaseMemoryArea=[0xb7942008,0xb7e42208)
>
cardTable=[0x8322f90,0x8325790)
>
objectHeaderTable=[0x8325798,0x8327f98)
>
summaryTable=[0x8327fa0,0x8331fa0)
> Hello world.
21
JavaME CDC
WHAT HAPPENS DURING THE BUILD
PROCESS
22
Step Utility
Input
Output
1
javac
src/share/classes/*.java
build/target_name/btclasses/*.class
2
JavaMemb build/target_name/btclasses/*.clas
erDepend s
build/target_name/generated/javavm
/runtime/tranlist.
3
zip
build/target_name/generated/java
vm/runtime/tranlist
build/target_name/btclasses.zip
4
javac
src/share/javavm/test/*.java
(Runtime classes CVM test files )
build/target_name/lib/cdc.jar
build/target_name/lib/foundation.jar
build/target_name/testclasses/*.class
5
zip
build/target_name/testclasses/*.cl
ass
build/target_name/testclasses.zip
6
javah
Runtime classes
JNI header files in
build/target_name/generated/jni/*.h
7
JavaCodeC build/target_name/btclasses.zip
ompact
JNI header files in
build/target_name/generated/jni/*.h
Preloaded class data structures
in
build/target_name/generated/javavm
/runtime/romjava*.c and romjava.h
Additional C file interfaces.
23
Step Utility
Input
Output
8
C compiler Native methods and CVM
source (.c) files
Object files in
build/target_name/obj/*.o
9
C compiler Preloaded classes in
build/target_name/generated/java
vm/runtime/romjava*.c
Object files in build/target_name/obj/
romjava*.o
A
archive
utility
Object files in
build/target_name/obj/romjava*.o
Object archive file in
build/target_name/obj/libromjava.a
B
linker
Object files in
build/target_name/obj/*.o from
step 8
Virtual machine binary* in
build/target_name/bin.
Object archive file in
build/target_name/obj/libromjava.
a from step 10
In build/linux-i686/directory
•bin/cvm: executable image
•lib/cdc.jar: JAR archive, default boot class path
•testclasses.zip: a collection of simple tests
24
JavaME CDC
GARBAGE COLLECTOR
25
Build Options
• -CVM_GCCHOICE
(Generational/marksweep/semispace)
• default: generational
• Example:
– -CVM_GCCHOICE=semispace
26
Runtime Options
• -Xgc:gc_specific_options(In generational is
youngGen=nnn in bytes)
• Default: 1M
27
Runtime Options
• -Xmssize (memory allocation pool)
• Default: 4M
• Example:
– -Xms6291456
– -Xms6144k
– -Xms6m
28
Source Organization
• src/share/javavm/include/gc_common.h
The shared GC interface.
• src/share/javavm/include/gc/gc_impl.h
The gcimpl GC interface that has to be implemented for each
GC.
• src/share/javavm/include/gc/<gcname>/gc_config.h
The configuration file for a specific GC.
• src/share/javavm/runtime/gc/<gcname>/gc_impl.c
The implementation file for a specific GC.
29
Execution Flow
1. CVM allocates memory using the shared routine CVMgcAllocNewInstance().
2. CVMgcAllocNewInstance() does some processing and calls the GC-specific
CVMgcimplAllocObject() to allocate the actual space for the object.
3. CVMgcimplAllocObject() performs the GC and calls the shared routine
CVMgcStopTheWorldAndGC() to stop all threads at GC-safe points.
4. CVMgcStopTheWorldAndGC() ensures that all threads rendezvous at GC-safe points. When that is
done, it calls the GC implementation CVMgcimplDoGC() to perform the GC action.
5. CVMgcimplDoGC() may call shared GC service routines to scan GC state: For example,
CVMgcScanRoots() to scan all roots or CVMobjectWalkRefs() to scan the pointers in a given object
or array.
6. When CVMgcimplDoGC() returns, all threads that were stopped at GC points resume execution.
Eventually, CVMgcAllocNewInstance() returns and the thread that originally initiated GC resumes
execution.
30
JavaME CDC
REFERENCE
31
CDCFOUNDATION_PORTING_GUIDE.PDF
32
JavaME CDC
<!--EOF->
33
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