Two new functions: jiffies_to_ktime() and ktime_to_jiffies(), we'll use them for timerfd deferred timers handling.
We fully reuse the logic from timespec implementations, so the functions are pretty straightforward.
The only tricky part is in headers: we have to include jiffies.h after we defined ktime_t, this is because ktime.h needs some declarations from jiffies.h (e.g. TICK_NSEC).
Signed-off-by: Anton Vorontsov anton.vorontsov@linaro.org --- include/linux/jiffies.h | 3 +++ include/linux/ktime.h | 3 ++- kernel/time.c | 23 +++++++++++++++++++++++ 3 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h index 265e2c3..4451241 100644 --- a/include/linux/jiffies.h +++ b/include/linux/jiffies.h @@ -6,6 +6,7 @@ #include <linux/types.h> #include <linux/time.h> #include <linux/timex.h> +#include <linux/ktime.h> #include <asm/param.h> /* for HZ */
/* @@ -303,6 +304,8 @@ extern void jiffies_to_timespec(const unsigned long jiffies, extern unsigned long timeval_to_jiffies(const struct timeval *value); extern void jiffies_to_timeval(const unsigned long jiffies, struct timeval *value); +extern unsigned long ktime_to_jiffies(ktime_t *value); +extern void jiffies_to_ktime(const unsigned long jiffies, ktime_t *value); extern clock_t jiffies_to_clock_t(unsigned long x); extern unsigned long clock_t_to_jiffies(unsigned long x); extern u64 jiffies_64_to_clock_t(u64 x); diff --git a/include/linux/ktime.h b/include/linux/ktime.h index 603bec2..9551856 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -22,7 +22,6 @@ #define _LINUX_KTIME_H
#include <linux/time.h> -#include <linux/jiffies.h>
/* * ktime_t: @@ -58,6 +57,8 @@ union ktime {
typedef union ktime ktime_t; /* Kill this */
+#include <linux/jiffies.h> + #define KTIME_MAX ((s64)~((u64)1 << 63)) #if (BITS_PER_LONG == 64) # define KTIME_SEC_MAX (KTIME_MAX / NSEC_PER_SEC) diff --git a/kernel/time.c b/kernel/time.c index ba744cf..82c06c5 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -29,6 +29,7 @@
#include <linux/export.h> #include <linux/timex.h> +#include <linux/ktime.h> #include <linux/capability.h> #include <linux/clocksource.h> #include <linux/errno.h> @@ -566,6 +567,28 @@ void jiffies_to_timeval(const unsigned long jiffies, struct timeval *value) } EXPORT_SYMBOL(jiffies_to_timeval);
+unsigned long ktime_to_jiffies(ktime_t *value) +{ + struct timespec ts = ktime_to_timespec(*value); + + /* + * nsecs_to_jiffies(ktime_to_ns(*ktime)) is unsafe as nsecs_to_jiffies + * doesn't handle MAX_JIFFY_OFFSET. So we reuse the logic from the + * timespec to jiffies conversion function. + */ + return timespec_to_jiffies(&ts); +} +EXPORT_SYMBOL(ktime_to_jiffies); + +void jiffies_to_ktime(const unsigned long jiffies, ktime_t *value) +{ + struct timespec ts; + + jiffies_to_timespec(jiffies, &ts); + *value = timespec_to_ktime(ts); +} +EXPORT_SYMBOL(jiffies_to_ktime); + /* * Convert jiffies/jiffies_64 to clock_t and back. */