1 /* 2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) 3 * Licensed under the GPL 4 */ 5 6 #include <stdio.h> 7 #include <stdlib.h> 8 #include <unistd.h> 9 #include <time.h> 10 #include <sys/time.h> 11 #include <signal.h> 12 #include <errno.h> 13 #include "kern_util.h" 14 #include "user.h" 15 #include "process.h" 16 #include "kern_constants.h" 17 #include "os.h" 18 #include "uml-config.h" 19 20 int set_interval(int is_virtual) 21 { 22 int usec = 1000000/hz(); 23 int timer_type = is_virtual ? ITIMER_VIRTUAL : ITIMER_REAL; 24 struct itimerval interval = ((struct itimerval) { { 0, usec }, 25 { 0, usec } }); 26 27 if(setitimer(timer_type, &interval, NULL) == -1) 28 return -errno; 29 30 return 0; 31 } 32 33 #ifdef UML_CONFIG_MODE_TT 34 void enable_timer(void) 35 { 36 set_interval(1); 37 } 38 #endif 39 40 void disable_timer(void) 41 { 42 struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }}); 43 if((setitimer(ITIMER_VIRTUAL, &disable, NULL) < 0) || 44 (setitimer(ITIMER_REAL, &disable, NULL) < 0)) 45 printk("disnable_timer - setitimer failed, errno = %d\n", 46 errno); 47 /* If there are signals already queued, after unblocking ignore them */ 48 signal(SIGALRM, SIG_IGN); 49 signal(SIGVTALRM, SIG_IGN); 50 } 51 52 void switch_timers(int to_real) 53 { 54 struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }}); 55 struct itimerval enable = ((struct itimerval) { { 0, 1000000/hz() }, 56 { 0, 1000000/hz() }}); 57 int old, new; 58 59 if(to_real){ 60 old = ITIMER_VIRTUAL; 61 new = ITIMER_REAL; 62 } 63 else { 64 old = ITIMER_REAL; 65 new = ITIMER_VIRTUAL; 66 } 67 68 if((setitimer(old, &disable, NULL) < 0) || 69 (setitimer(new, &enable, NULL))) 70 printk("switch_timers - setitimer failed, errno = %d\n", 71 errno); 72 } 73 74 #ifdef UML_CONFIG_MODE_TT 75 void uml_idle_timer(void) 76 { 77 if(signal(SIGVTALRM, SIG_IGN) == SIG_ERR) 78 panic("Couldn't unset SIGVTALRM handler"); 79 80 set_handler(SIGALRM, (__sighandler_t) alarm_handler, 81 SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1); 82 set_interval(0); 83 } 84 #endif 85 86 unsigned long long os_nsecs(void) 87 { 88 struct timeval tv; 89 90 gettimeofday(&tv, NULL); 91 return((unsigned long long) tv.tv_sec * BILLION + tv.tv_usec * 1000); 92 } 93 94 void idle_sleep(int secs) 95 { 96 struct timespec ts; 97 98 ts.tv_sec = secs; 99 ts.tv_nsec = 0; 100 nanosleep(&ts, NULL); 101 } 102