/* * RTLinux irq test * * measures semaphore wakeup operation performance * *  (C) FSMLabs  2000. Michael Barabanov <baraban@fsmlabs.com> *  Released under the GNU GENERAL PUBLIC LICENSE Version 2, June 1991 *  Any use of this code must include this notice. */#include <rtl.h>#include <rtl_fifo.h>#include <time.h>#include <rtl_sched.h>#include <rtl_sync.h>#include <pthread.h>#include <unistd.h>#include <rtl_debug.h>#include <errno.h>#include <semaphore.h>#include "common.h"int irq=14;int ntests=100;int setfocus=0; /* 0 or 1 */MODULE_PARM(irq,"i");MODULE_PARM(ntests,"i");MODULE_PARM(setfocus,"i");pthread_t thread;int fd_fifo;hrtime_t irqtime;sem_t irqsem;unsigned int intr_handler(unsigned int irq, struct pt_regs *regs){/* 	rtl_printf("%d", rtl_getcpuid()); */	irqtime = gethrtime();	rtl_global_pend_irq (irq);	sem_post(&irqsem);	return 0;}void *thread_code(void *param) {	hrtime_t diff;	hrtime_t now;	hrtime_t min_diff;	hrtime_t max_diff;	struct sample samp;	int i;	int cpu_id = rtl_getcpuid();	rtl_printf ("Measurement task starts on CPU %d\n", cpu_id);	fd_fifo = open("/dev/rtf0", O_NONBLOCK);	if (fd_fifo < 0) {		rtl_printf("/dev/rtf0 open returned %d\n", fd_fifo);		return (void *) -1;	}	do {		min_diff = 2000000000;		max_diff = -2000000000;		for (i = 0; i < ntests; i++) {			sem_wait (&irqsem);			now = gethrtime();			diff = now - irqtime;			if (diff < min_diff) {				min_diff = diff;			}			if (diff > max_diff) {				max_diff = diff;			}		}		samp.min = min_diff;		samp.max = max_diff;		write (fd_fifo, &samp, sizeof(samp));	} while (1);	return 0;}unsigned long oldaffinity;int init_module(void){	int ret;	unsigned long affinity = 1 << rtl_getcpuid();	rtf_destroy(0);	rtf_create(0, 4000);	ret = rtl_request_irq (irq, intr_handler);	if (ret) {		rtl_printf("failed to get irq%d: %d\n", irq, ret);	} else {		rtl_printf("got irq%d\n", irq);	}	if (setfocus) {		rtl_printf("setting irq%d distribution mask to %x\n", irq, affinity);		rtl_irq_set_affinity (irq, &affinity, &oldaffinity);	}	sem_init (&irqsem, 1, 0);	rtl_printf("RTLinux measurement module on CPU %d\n",rtl_getcpuid());	pthread_create (&thread,  NULL, thread_code, (void *)1);	return 0;}void cleanup_module(void){        rtl_printf ("Removing module on CPU %d\n", rtl_getcpuid());	rtl_free_irq (irq);	if (setfocus) {		rtl_irq_set_affinity (irq, &oldaffinity, NULL);	}	rtl_printf("freed irq%d\n", irq);	pthread_cancel (thread);	pthread_join (thread, NULL);	sem_destroy (&irqsem);	close(fd_fifo);	rtf_destroy(0);}