diff options
| author | Jeff Dike <jdike@addtoit.com> | 2007-05-06 23:51:51 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-07 21:13:04 +0200 |
| commit | b7ec15bd004f4524bf091f851348da2ccb519e4f (patch) | |
| tree | 9f367c3e81c91a8cc86ee477c6e250341512cf1d /arch/um | |
| parent | uml: out of tmpfs space error clarification (diff) | |
| download | linux-b7ec15bd004f4524bf091f851348da2ccb519e4f.tar.xz linux-b7ec15bd004f4524bf091f851348da2ccb519e4f.zip | |
uml: virtualized time fix
With the current timekeeping, !CONFIG_UML_REAL_TIME_CLOCK has
inconsistent behavior. Previously, gettimeofday could be (and was)
isolated from the clock ticking. Now, it's not, so when
CONFIG_UML_REAL_TIME_CLOCK is disabled, gettimeofday must progress in
lockstep with the clock, making it fully virtual.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/kernel/time.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c index 9fd80ee3eef6..cd7349de8ca6 100644 --- a/arch/um/kernel/time.c +++ b/arch/um/kernel/time.c @@ -34,8 +34,8 @@ unsigned long long sched_clock(void) return (unsigned long long)jiffies_64 * (1000000000 / HZ); } -static unsigned long long prev_nsecs[NR_CPUS]; #ifdef CONFIG_UML_REAL_TIME_CLOCK +static unsigned long long prev_nsecs[NR_CPUS]; static long long delta[NR_CPUS]; /* Deviation per interval */ #endif @@ -94,7 +94,12 @@ irqreturn_t um_timer(int irq, void *dev) do_timer(1); +#ifdef CONFIG_UML_REAL_TIME_CLOCK nsecs = get_time(); +#else + nsecs = (unsigned long long) xtime.tv_sec * BILLION + xtime.tv_nsec + + BILLION / HZ; +#endif xtime.tv_sec = nsecs / NSEC_PER_SEC; xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC; @@ -127,13 +132,18 @@ void time_init(void) nsecs = os_nsecs(); set_normalized_timespec(&wall_to_monotonic, -nsecs / BILLION, -nsecs % BILLION); + set_normalized_timespec(&xtime, nsecs / BILLION, nsecs % BILLION); late_time_init = register_timer; } void do_gettimeofday(struct timeval *tv) { +#ifdef CONFIG_UML_REAL_TIME_CLOCK unsigned long long nsecs = get_time(); - +#else + unsigned long long nsecs = (unsigned long long) xtime.tv_sec * BILLION + + xtime.tv_nsec; +#endif tv->tv_sec = nsecs / NSEC_PER_SEC; /* Careful about calculations here - this was originally done as * (nsecs - tv->tv_sec * NSEC_PER_SEC) / NSEC_PER_USEC |