Posix compliant CLOCK_PROCESS/THREAD_CPUTIME_ID V5

[Christoph Lameter <clameter at sgi dot com>]

This version uses an offset field in the task and signal structs
to store offsets for the thread and process clock. It also includes
the check in timer_create for REALTIME or MONOTONIC. The
clocks are now independent and therefore the thread clock is not
clearedby clock_settime(CLOCK_PROCESS_CPUTIME_ID) in the testrun:

Single Thread Testing
  CLOCK_THREAD_CPUTIME_ID=          0.374943000 resolution= 0.000999848
 CLOCK_PROCESS_CPUTIME_ID=          0.374943000 resolution= 0.000999848
Multi Thread Testing
Starting Thread: 0 1 2 3 4 5 6 7 8 9
 Joining Thread: 0 1 2 3 4 5 6 7 8 9
0 Cycles=      0 Thread=  0.000000000ns Process=  0.000999848ns
1 Cycles=1000000 Thread=  0.036994376ns Process=  0.315951968ns
2 Cycles=2000000 Thread=  0.073988752ns Process=  0.086986776ns
3 Cycles=3000000 Thread=  0.109983280ns Process=  0.517921264ns
4 Cycles=4000000 Thread=  0.146977656ns Process=  0.563914272ns
5 Cycles=5000000 Thread=  0.180972488ns Process=  1.043841312ns
6 Cycles=6000000 Thread=  0.218966712ns Process=  1.112830824ns
7 Cycles=7000000 Thread=  0.254961240ns Process=  1.620753608ns
8 Cycles=8000000 Thread=  0.290955768ns Process=  1.490773368ns
9 Cycles=9000000 Thread=  0.326950296ns Process=  1.641750416ns

Clock status at the end of the timer tests:
          Gettimeofday() = 1096484938.561351000
           CLOCK_REALTIME= 1096484938.561363000 resolution= 0.000999848
          CLOCK_MONOTONIC=        157.633669432 resolution= 0.000999848
 CLOCK_PROCESS_CPUTIME_ID=          1.641750416 resolution= 0.000999848
  CLOCK_THREAD_CPUTIME_ID=          0.375942848 resolution= 0.000999848

Attachment: thread_process_time_v5
Description: V5 of patch

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <errno.h>
#include <asm/unistd.h>
#include <pthread.h>

#define clock_getres(x,y) syscall(__NR_clock_getres, x,y)
#define clock_gettime(x,y) syscall(__NR_clock_gettime, x, y)
#define clock_settime(x,y) syscall(__NR_clock_settime, x, y)

void pr(int clock,const char *n)
{
	struct timespec tv = {1,2};
	struct timespec res = {3,4};
	int rc;


	rc=clock_getres(clock,&res);
	if (rc) {
		printf("getres return code on %s=%d errno=%d\n",n,rc,errno);
	}
	rc=clock_gettime(clock,&tv);
	if (rc) {
		printf("gettime return code on %s=%d errno=%d\n",n,rc, errno);
	} 
	else 
	printf("%25s=% 11d.%09d resolution=% 2d.%09d\n",n,tv.tv_sec,tv.tv_nsec,res.tv_sec,res.tv_nsec);
}

int y;

void kx(long long x) {
	y=x;
};

struct timespec zero;

pthread_t thread[10];

struct tinfo {
	int i;
	struct timespec ttime,ptime;
} tinf[10];

void *thread_function(void *x) {
	struct tinfo *t=x;
	int i;
	
	for(i=1;i< t->i;i++) kx(1000000000000LL/i);
	clock_gettime(CLOCK_THREAD_CPUTIME_ID,&t->ttime);
	clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&t->ptime);
}

int main(char argc, char *argv[])
{
	struct timespec tv;
	int i;

	/* Waste some time */
	printf("Single Thread Testing\n");
	
	for(i=1;i<10000000;i++) kx(1000000000000LL/i);
	pr(CLOCK_THREAD_CPUTIME_ID,"CLOCK_THREAD_CPUTIME_ID");
	pr(CLOCK_PROCESS_CPUTIME_ID,"CLOCK_PROCESS_CPUTIME_ID");
	/* Waste some more time in threads */
	printf("Multi Thread Testing\nStarting Thread:");
	clock_settime(CLOCK_PROCESS_CPUTIME_ID,&zero);
	for(i=0;i<10;i++) {
		tinf[i].i=i*1000000;
		if (pthread_create(&thread[i], NULL, thread_function, tinf+i))
			perror("thread");
		else
			printf(" %d",i);
	}
	printf("\n Joining Thread:");
	for(i=0;i<10;i++) if (pthread_join( thread[i], NULL)) perror("join"); else printf(" %d",i);
	printf("\n");
	for(i=0;i<10;i++) {
		printf("%d Cycles=%7d Thread=% 3d.%09dns Process=% 3d.%09dns\n",i,tinf[i].i,tinf[i].ttime.tv_sec,tinf[i].ttime.tv_nsec,tinf[i].ptime.tv_sec,tinf[i].ptime.tv_nsec);
	}	
	gettimeofday((struct timeval *)&tv);
	tv.tv_nsec = tv.tv_nsec*1000;
	printf("\nClock status at the end of the timer tests:\n");
	printf("          Gettimeofday() =% 11d.%09d\n",tv.tv_sec,tv.tv_nsec);
	pr(CLOCK_REALTIME,"CLOCK_REALTIME");
	pr(CLOCK_MONOTONIC,"CLOCK_MONOTONIC");
	pr(CLOCK_PROCESS_CPUTIME_ID,"CLOCK_PROCESS_CPUTIME_ID");
	pr(CLOCK_THREAD_CPUTIME_ID,"CLOCK_THREAD_CPUTIME_ID");
	printf("\n");
}