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 "user_util.h" 14 #include "kern_util.h" 15 #include "user.h" 16 #include "process.h" 17 #include "kern_constants.h" 18 #include "os.h" 19 #include "uml-config.h" 20 21 int set_interval(int is_virtual) 22 { 23 int usec = 1000000/hz(); 24 int timer_type = is_virtual ? ITIMER_VIRTUAL : ITIMER_REAL; 25 struct itimerval interval = ((struct itimerval) { { 0, usec }, 26 { 0, usec } }); 27 28 if(setitimer(timer_type, &interval, NULL) == -1) 29 return -errno; 30 31 return 0; 32 } 33 34 #ifdef UML_CONFIG_MODE_TT 35 void enable_timer(void) 36 { 37 set_interval(1); 38 } 39 #endif 40 41 void disable_timer(void) 42 { 43 struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }}); 44 if((setitimer(ITIMER_VIRTUAL, &disable, NULL) < 0) || 45 (setitimer(ITIMER_REAL, &disable, NULL) < 0)) 46 printk("disnable_timer - setitimer failed, errno = %d\n", 47 errno); 48 /* If there are signals already queued, after unblocking ignore them */ 49 signal(SIGALRM, SIG_IGN); 50 signal(SIGVTALRM, SIG_IGN); 51 } 52 53 void switch_timers(int to_real) 54 { 55 struct itimerval disable = ((struct itimerval) { { 0, 0 }, { 0, 0 }}); 56 struct itimerval enable = ((struct itimerval) { { 0, 1000000/hz() }, 57 { 0, 1000000/hz() }}); 58 int old, new; 59 60 if(to_real){ 61 old = ITIMER_VIRTUAL; 62 new = ITIMER_REAL; 63 } 64 else { 65 old = ITIMER_REAL; 66 new = ITIMER_VIRTUAL; 67 } 68 69 if((setitimer(old, &disable, NULL) < 0) || 70 (setitimer(new, &enable, NULL))) 71 printk("switch_timers - setitimer failed, errno = %d\n", 72 errno); 73 } 74 75 #ifdef UML_CONFIG_MODE_TT 76 void uml_idle_timer(void) 77 { 78 if(signal(SIGVTALRM, SIG_IGN) == SIG_ERR) 79 panic("Couldn't unset SIGVTALRM handler"); 80 81 set_handler(SIGALRM, (__sighandler_t) alarm_handler, 82 SA_RESTART, SIGUSR1, SIGIO, SIGWINCH, SIGVTALRM, -1); 83 set_interval(0); 84 } 85 #endif 86 87 unsigned long long os_nsecs(void) 88 { 89 struct timeval tv; 90 91 gettimeofday(&tv, NULL); 92 return((unsigned long long) tv.tv_sec * BILLION + tv.tv_usec * 1000); 93 } 94 95 void idle_sleep(int secs) 96 { 97 struct timespec ts; 98 99 ts.tv_sec = secs; 100 ts.tv_nsec = 0; 101 nanosleep(&ts, NULL); 102 } 103