diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/um/include/process.h | 4 | ||||
| -rw-r--r-- | arch/um/os-Linux/signal.c | 1 | ||||
| -rw-r--r-- | arch/um/os-Linux/time.c | 54 |
3 files changed, 53 insertions, 6 deletions
diff --git a/arch/um/include/process.h b/arch/um/include/process.h index 838b4802ce5..bb873a51262 100644 --- a/arch/um/include/process.h +++ b/arch/um/include/process.h @@ -11,7 +11,7 @@ /* Copied from linux/compiler-gcc.h since we can't include it directly */ #define barrier() __asm__ __volatile__("": : :"memory") -extern void sig_handler(int sig, struct sigcontext sc); -extern void alarm_handler(int sig, struct sigcontext sc); +extern void sig_handler(int sig, struct sigcontext *sc); +extern void alarm_handler(int sig, struct sigcontext *sc); #endif diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index 3f1694b134c..5aade6027e4 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c @@ -12,6 +12,7 @@ #include "as-layout.h" #include "kern_util.h" #include "os.h" +#include "process.h" #include "sysdep/barrier.h" #include "sysdep/sigcontext.h" #include "user.h" diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c index e4928059946..bee98f466d6 100644 --- a/arch/um/os-Linux/time.c +++ b/arch/um/os-Linux/time.c @@ -9,7 +9,9 @@ #include <time.h> #include <sys/time.h> #include "kern_constants.h" +#include "kern_util.h" #include "os.h" +#include "process.h" #include "user.h" int set_interval(void) @@ -58,12 +60,17 @@ static inline long long timeval_to_ns(const struct timeval *tv) long long disable_timer(void) { struct itimerval time = ((struct itimerval) { { 0, 0 }, { 0, 0 } }); + int remain, max = UM_NSEC_PER_SEC / UM_HZ; if (setitimer(ITIMER_VIRTUAL, &time, &time) < 0) printk(UM_KERN_ERR "disable_timer - setitimer failed, " "errno = %d\n", errno); - return timeval_to_ns(&time.it_value); + remain = timeval_to_ns(&time.it_value); + if (remain > max) + remain = max; + + return remain; } long long os_nsecs(void) @@ -79,7 +86,44 @@ static int after_sleep_interval(struct timespec *ts) { return 0; } + +static void deliver_alarm(void) +{ + alarm_handler(SIGVTALRM, NULL); +} + +static unsigned long long sleep_time(unsigned long long nsecs) +{ + return nsecs; +} + #else +unsigned long long last_tick; +unsigned long long skew; + +static void deliver_alarm(void) +{ + unsigned long long this_tick = os_nsecs(); + int one_tick = UM_NSEC_PER_SEC / UM_HZ; + + if (last_tick == 0) + last_tick = this_tick - one_tick; + + skew += this_tick - last_tick; + + while (skew >= one_tick) { + alarm_handler(SIGVTALRM, NULL); + skew -= one_tick; + } + + last_tick = this_tick; +} + +static unsigned long long sleep_time(unsigned long long nsecs) +{ + return nsecs > skew ? nsecs - skew : 0; +} + static inline long long timespec_to_us(const struct timespec *ts) { return ((long long) ts->tv_sec * UM_USEC_PER_SEC) + @@ -102,6 +146,8 @@ static int after_sleep_interval(struct timespec *ts) */ if (start_usecs > usec) start_usecs = usec; + + start_usecs -= skew / UM_NSEC_PER_USEC; 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 }); @@ -113,8 +159,6 @@ static int after_sleep_interval(struct timespec *ts) } #endif -extern void alarm_handler(int sig, struct sigcontext *sc); - void idle_sleep(unsigned long long nsecs) { struct timespec ts; @@ -126,10 +170,12 @@ void idle_sleep(unsigned long long nsecs) */ if (nsecs == 0) nsecs = UM_NSEC_PER_SEC / UM_HZ; + + nsecs = sleep_time(nsecs); ts = ((struct timespec) { .tv_sec = nsecs / UM_NSEC_PER_SEC, .tv_nsec = nsecs % UM_NSEC_PER_SEC }); if (nanosleep(&ts, &ts) == 0) - alarm_handler(SIGVTALRM, NULL); + deliver_alarm(); after_sleep_interval(&ts); } |