timekeeping: Add ktime_get_coarse_with_offset

I have run into a couple of drivers using current_kernel_time()
suffering from the y2038 problem, and they could be converted
to using ktime_t, but don't have interfaces that skip the nanosecond
calculation at the moment.

This introduces ktime_get_coarse_with_offset() as a simpler
variant of ktime_get_with_offset(), and adds wrappers for the
three time domains we support with the existing function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: y2038@lists.linaro.org
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/20180427134016.2525989-5-arnd@arndb.de
This commit is contained in:
Arnd Bergmann 2018-04-27 15:40:15 +02:00 committed by Thomas Gleixner
parent fb7fcc96a8
commit b9ff604cff
2 changed files with 35 additions and 0 deletions

View File

@ -51,6 +51,7 @@ enum tk_offsets {
extern ktime_t ktime_get(void);
extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
extern ktime_t ktime_get_raw(void);
extern u32 ktime_get_resolution_ns(void);
@ -63,6 +64,11 @@ static inline ktime_t ktime_get_real(void)
return ktime_get_with_offset(TK_OFFS_REAL);
}
static inline ktime_t ktime_get_coarse_real(void)
{
return ktime_get_coarse_with_offset(TK_OFFS_REAL);
}
/**
* ktime_get_boottime - Returns monotonic time since boot in ktime_t format
*
@ -74,6 +80,11 @@ static inline ktime_t ktime_get_boottime(void)
return ktime_get_with_offset(TK_OFFS_BOOT);
}
static inline ktime_t ktime_get_coarse_boottime(void)
{
return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
}
/**
* ktime_get_clocktai - Returns the TAI time of day in ktime_t format
*/
@ -82,6 +93,11 @@ static inline ktime_t ktime_get_clocktai(void)
return ktime_get_with_offset(TK_OFFS_TAI);
}
static inline ktime_t ktime_get_coarse_clocktai(void)
{
return ktime_get_coarse_with_offset(TK_OFFS_TAI);
}
/**
* ktime_mono_to_real - Convert monotonic time to clock realtime
*/

View File

@ -795,6 +795,25 @@ ktime_t ktime_get_with_offset(enum tk_offsets offs)
}
EXPORT_SYMBOL_GPL(ktime_get_with_offset);
ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs)
{
struct timekeeper *tk = &tk_core.timekeeper;
unsigned int seq;
ktime_t base, *offset = offsets[offs];
WARN_ON(timekeeping_suspended);
do {
seq = read_seqcount_begin(&tk_core.seq);
base = ktime_add(tk->tkr_mono.base, *offset);
} while (read_seqcount_retry(&tk_core.seq, seq));
return base;
}
EXPORT_SYMBOL_GPL(ktime_get_coarse_with_offset);
/**
* ktime_mono_to_any() - convert mononotic time to any other time
* @tmono: time to convert.