/*
+ * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
+ * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
+ * Copyright (C) 2012-2014 Cisco Systems
* Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <sys/time.h>
#include <kern_util.h>
#include <os.h>
-#include "internal.h"
+#include <string.h>
+#include <timer-internal.h>
-int set_interval(void)
-{
- int usec = UM_USEC_PER_SEC / UM_HZ;
- struct itimerval interval = ((struct itimerval) { { 0, usec },
- { 0, usec } });
-
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+static timer_t event_high_res_timer = 0;
- return 0;
+static inline long long timeval_to_ns(const struct timeval *tv)
+{
+ return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
+ tv->tv_usec * UM_NSEC_PER_USEC;
}
-int timer_one_shot(int ticks)
+static inline long long timespec_to_ns(const struct timespec *ts)
{
- unsigned long usec = ticks * UM_USEC_PER_SEC / UM_HZ;
- unsigned long sec = usec / UM_USEC_PER_SEC;
- struct itimerval interval;
-
- usec %= UM_USEC_PER_SEC;
- interval = ((struct itimerval) { { 0, 0 }, { sec, usec } });
+ return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) +
+ ts->tv_nsec;
+}
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+long long os_persistent_clock_emulation (void) {
+ struct timespec realtime_tp;
- return 0;
+ clock_gettime(CLOCK_REALTIME, &realtime_tp);
+ return timespec_to_ns(&realtime_tp);
}
/**
- * timeval_to_ns - Convert timeval to nanoseconds
- * @ts: pointer to the timeval variable to be converted
- *
- * Returns the scalar nanosecond representation of the timeval
- * parameter.
- *
- * Ripped from linux/time.h because it's a kernel header, and thus
- * unusable from here.
+ * os_timer_create() - create an new posix (interval) timer
*/
-static inline long long timeval_to_ns(const struct timeval *tv)
-{
- return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
- tv->tv_usec * UM_NSEC_PER_USEC;
+int os_timer_create(void* timer) {
+
+ timer_t* t = timer;
+
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
+
+ if (timer_create(
+ CLOCK_MONOTONIC,
+ NULL,
+ t) == -1) {
+ return -1;
+ }
+ return 0;
}
-long long disable_timer(void)
+int os_timer_set_interval(void* timer, void* i)
{
- struct itimerval time = ((struct itimerval) { { 0, 0 }, { 0, 0 } });
- long long remain, max = UM_NSEC_PER_SEC / UM_HZ;
+ struct itimerspec its;
+ unsigned long long nsec;
+ timer_t* t = timer;
+ struct itimerspec* its_in = i;
- if (setitimer(ITIMER_VIRTUAL, &time, &time) < 0)
- printk(UM_KERN_ERR "disable_timer - setitimer failed, "
- "errno = %d\n", errno);
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
- remain = timeval_to_ns(&time.it_value);
- if (remain > max)
- remain = max;
+ nsec = UM_NSEC_PER_SEC / UM_HZ;
- return remain;
-}
+ if(its_in != NULL) {
+ its.it_value.tv_sec = its_in->it_value.tv_sec;
+ its.it_value.tv_nsec = its_in->it_value.tv_nsec;
+ } else {
+ its.it_value.tv_sec = 0;
+ its.it_value.tv_nsec = nsec;
+ }
-long long os_nsecs(void)
-{
- struct timeval tv;
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = nsec;
- gettimeofday(&tv, NULL);
- return timeval_to_ns(&tv);
-}
+ if(timer_settime(*t, 0, &its, NULL) == -1) {
+ return -errno;
+ }
-#ifdef UML_CONFIG_NO_HZ_COMMON
-static int after_sleep_interval(struct timespec *ts)
-{
return 0;
}
-static void deliver_alarm(void)
+/**
+ * os_timer_remain() - returns the remaining nano seconds of the given interval
+ * timer
+ * Because this is the remaining time of an interval timer, which correspondends
+ * to HZ, this value can never be bigger than one second. Just
+ * the nanosecond part of the timer is returned.
+ * The returned time is relative to the start time of the interval timer.
+ * Return an negative value in an error case.
+ */
+long os_timer_remain(void* timer)
{
- alarm_handler(SIGVTALRM, NULL, NULL);
-}
+ struct itimerspec its;
+ timer_t* t = timer;
-static unsigned long long sleep_time(unsigned long long nsecs)
-{
- return nsecs;
-}
+ if(t == NULL) {
+ t = &event_high_res_timer;
+ }
-#else
-unsigned long long last_tick;
-unsigned long long skew;
+ if(timer_gettime(t, &its) == -1) {
+ return -errno;
+ }
-static void deliver_alarm(void)
-{
- unsigned long long this_tick = os_nsecs();
- int one_tick = UM_NSEC_PER_SEC / UM_HZ;
+ return its.it_value.tv_nsec;
+}
- /* Protection against the host's time going backwards */
- if ((last_tick != 0) && (this_tick < last_tick))
- this_tick = last_tick;
+int os_timer_one_shot(int ticks)
+{
+ struct itimerspec its;
+ unsigned long long nsec;
+ unsigned long sec;
- if (last_tick == 0)
- last_tick = this_tick - one_tick;
+ nsec = (ticks + 1);
+ sec = nsec / UM_NSEC_PER_SEC;
+ nsec = nsec % UM_NSEC_PER_SEC;
- skew += this_tick - last_tick;
+ its.it_value.tv_sec = nsec / UM_NSEC_PER_SEC;
+ its.it_value.tv_nsec = nsec;
- while (skew >= one_tick) {
- alarm_handler(SIGVTALRM, NULL, NULL);
- skew -= one_tick;
- }
+ its.it_interval.tv_sec = 0;
+ its.it_interval.tv_nsec = 0; // we cheat here
- last_tick = this_tick;
+ timer_settime(event_high_res_timer, 0, &its, NULL);
+ return 0;
}
-static unsigned long long sleep_time(unsigned long long nsecs)
+/**
+ * os_timer_disable() - disable the posix (interval) timer
+ * Returns the remaining interval timer time in nanoseconds
+ */
+long long os_timer_disable(void)
{
- return nsecs > skew ? nsecs - skew : 0;
-}
+ struct itimerspec its;
-static inline long long timespec_to_us(const struct timespec *ts)
-{
- return ((long long) ts->tv_sec * UM_USEC_PER_SEC) +
- ts->tv_nsec / UM_NSEC_PER_USEC;
+ memset(&its, 0, sizeof(struct itimerspec));
+ timer_settime(event_high_res_timer, 0, &its, &its);
+
+ return its.it_value.tv_sec * UM_NSEC_PER_SEC + its.it_value.tv_nsec;
}
-static int after_sleep_interval(struct timespec *ts)
+long long os_vnsecs(void)
{
- int usec = UM_USEC_PER_SEC / UM_HZ;
- long long start_usecs = timespec_to_us(ts);
- struct timeval tv;
- struct itimerval interval;
-
- /*
- * It seems that rounding can increase the value returned from
- * setitimer to larger than the one passed in. Over time,
- * this will cause the remaining time to be greater than the
- * tick interval. If this happens, then just reduce the first
- * tick to the interval value.
- */
- if (start_usecs > usec)
- start_usecs = usec;
-
- start_usecs -= skew / UM_NSEC_PER_USEC;
- if (start_usecs < 0)
- start_usecs = 0;
+ struct timespec ts;
- tv = ((struct timeval) { .tv_sec = start_usecs / UM_USEC_PER_SEC,
- .tv_usec = start_usecs % UM_USEC_PER_SEC });
- interval = ((struct itimerval) { { 0, usec }, tv });
+ clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&ts);
+ return timespec_to_ns(&ts);
+}
- if (setitimer(ITIMER_VIRTUAL, &interval, NULL) == -1)
- return -errno;
+long long os_nsecs(void)
+{
+ struct timespec ts;
- return 0;
+ clock_gettime(CLOCK_MONOTONIC,&ts);
+ return timespec_to_ns(&ts);
}
-#endif
-void idle_sleep(unsigned long long nsecs)
+/**
+ * os_idle_sleep() - sleep for a given time of nsecs
+ * @nsecs: nanoseconds to sleep
+ */
+void os_idle_sleep(unsigned long long nsecs)
{
struct timespec ts;
- /*
- * nsecs can come in as zero, in which case, this starts a
- * busy loop. To prevent this, reset nsecs to the tick
- * interval if it is zero.
- */
- if (nsecs == 0)
- nsecs = UM_NSEC_PER_SEC / UM_HZ;
+ if (nsecs <= 0) {
+ return;
+ }
- nsecs = sleep_time(nsecs);
- ts = ((struct timespec) { .tv_sec = nsecs / UM_NSEC_PER_SEC,
- .tv_nsec = nsecs % UM_NSEC_PER_SEC });
+ ts = ((struct timespec) {
+ .tv_sec = nsecs / UM_NSEC_PER_SEC,
+ .tv_nsec = nsecs % UM_NSEC_PER_SEC
+ });
- if (nanosleep(&ts, &ts) == 0)
+ /*
+ * Relay the signal if clock_nanosleep is interrupted.
+ */
+ if (clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL)) {
deliver_alarm();
- after_sleep_interval(&ts);
+ }
}
Code Review / kvmfornfv.git / blobdiff