Java Stand-alone Applications on z/OS, Volume I

170 Java Stand-alone Applications on z/OS Volume 1

com_ibm_itso_timer_ThreadSafeTimeUsed.c

#include "com_ibm_itso_timer_ThreadSafeTimeUsed.h"

void CPU (void *);

#pragma linkage(CPU,OS)

JNIEXPORT jlong JNICALL Java_com_ibm_itso_timer_ThreadSafeTimeUsed_timeUsed

(JNIEnv * env, jobject thisObject) {

jlong microseconds = 0L;

CPU(&microseconds);

return microseconds;

}

cpu.s

* PRINT NOGEN

R1 EQU 1

R2 EQU 2

R3 EQU 3

R4 EQU 4

R5 EQU 5

R6 EQU 6

R7 EQU 7

R8 EQU 8

R9 EQU 9

R10 EQU 10

R11 EQU 11

R12 EQU 12

R13 EQU 13

R14 EQU 14

R15 EQU 15

CPU_PARMS DSECT

CPU_PARMS_START DS 0F

CPU_PARMS_FIRST_PTR DS F

CPU RMODE ANY

CPU AMODE 31

CPU CSECT

USING CPU,R15

B DOIT

DC CL8'CPU--STR'

DOIT DS 0H

SAVE (14,12)

LR R10,R15

HERE DS 0H

L R2,0(,R1)

Chapter 5. Measuring performance and application profiling 171

TIMEUSED STORADR=(2),LINKAGE=SYSTEM,CPU=MIC

RETURN (14,12),RC=0

DC CL8'CPU--END'

END

Build commands

javac com/ibm/itso/timer/ThreadSafeTimeUsed

javah com.ibm.itso.timer.ThreadSafeTimeUsed

c89 -o libtimeused.so -W "l,xplink,dll" -W

"c,langlvl(extended),xplink,dll,exportall" -I/usr/lpp/java/J1.4/include

com_ibm_itso_timer_ThreadSafeTimeUsed.c cpu.s

/usr/lpp/java/J1.4/bin/classic/libjvm.x

172 Java Stand-alone Applications on z/OS Volume 1