1 /* 2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include <stddef.h> 7 #include <errno.h> 8 #include <signal.h> 9 #include <time.h> 10 #include <sys/time.h> 11 #include "kern_constants.h" 12 #include "os.h" 13 #include "user.h" 14 15 int set_interval(void) 16 { 17 int usec = UM_USEC_PER_SEC / UM_HZ; 18 struct itimerval interval = ((struct itimerval) { { 0, usec }, 19 { 0, usec } }); 20 21 if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1) 22 return -errno; 23 24 return 0; 25 } 26 27 int timer_one_shot(int ticks) 28 { 29 unsigned long usec = ticks * UM_USEC_PER_SEC / UM_HZ; 30 unsigned long sec = usec / UM_USEC_PER_SEC; 31 struct itimerval interval; 32 33 usec %= UM_USEC_PER_SEC; 34 interval = ((struct itimerval) { { 0, 0 }, { sec, usec } }); 35 36 if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1) 37 return -errno; 38 39 return 0; 40 } 41 42 /** 43 * timeval_to_ns - Convert timeval to nanoseconds 44 * @ts: pointer to the timeval variable to be converted 45 * 46 * Returns the scalar nanosecond representation of the timeval 47 * parameter. 48 * 49 * Ripped from linux/time.h because it's a kernel header, and thus 50 * unusable from here. 51 */ 52 static inline long long timeval_to_ns(const struct timeval *tv) 53 { 54 return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) + 55 tv->tv_usec * UM_NSEC_PER_USEC; 56 } 57 58 long long disable_timer(void) 59 { 60 struct itimerval time = ((struct itimerval) { { 0, 0 }, { 0, 0 } }); 61 62 if(setitimer(ITIMER_VIRTUAL, &time, &time) < 0) 63 printk(UM_KERN_ERR "disable_timer - setitimer failed, " 64 "errno = %d\n", errno); 65 66 return timeval_to_ns(&time.it_value); 67 } 68 69 long long os_nsecs(void) 70 { 71 struct timeval tv; 72 73 gettimeofday(&tv, NULL); 74 return timeval_to_ns(&tv); 75 } 76 77 extern void alarm_handler(int sig, struct sigcontext *sc); 78 79 void idle_sleep(unsigned long long nsecs) 80 { 81 struct timespec ts = { .tv_sec = nsecs / UM_NSEC_PER_SEC, 82 .tv_nsec = nsecs % UM_NSEC_PER_SEC }; 83 84 if (nanosleep(&ts, &ts) == 0) 85 alarm_handler(SIGVTALRM, NULL); 86 } 87