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author | John Stultz <john.stultz@linaro.org> | 2014-07-16 21:03:53 +0000 |
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committer | John Stultz <john.stultz@linaro.org> | 2014-07-23 10:16:50 -0700 |
commit | 24e4a8c3e8868874835b0f1ad6dd417341e99822 (patch) | |
tree | d71c666cc53db7e0d906e838f23ff67855b86b6b /kernel/time | |
parent | 76f4108892d9a9e3408bba839914f97a54086a6f (diff) | |
download | linux-24e4a8c3e8868874835b0f1ad6dd417341e99822.tar.gz linux-24e4a8c3e8868874835b0f1ad6dd417341e99822.tar.bz2 linux-24e4a8c3e8868874835b0f1ad6dd417341e99822.zip |
ktime: Kill non-scalar ktime_t implementation for 2038
The non-scalar ktime_t implementation is basically a timespec
which has to be changed to support dates past 2038 on 32bit
systems.
This patch removes the non-scalar ktime_t implementation, forcing
the scalar s64 nanosecond version on all architectures.
This may have additional performance overhead on some 32bit
systems when converting between ktime_t and timespec structures,
however the majority of 32bit systems (arm and i386) were already
using scalar ktime_t, so no performance regressions will be seen
on those platforms.
On affected platforms, I'm open to finding optimizations, including
avoiding converting to timespecs where possible.
[ tglx: We can now cleanup the ktime_t.tv64 mess, but thats a
different issue and we can throw a coccinelle script at it ]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'kernel/time')
-rw-r--r-- | kernel/time/Kconfig | 4 | ||||
-rw-r--r-- | kernel/time/hrtimer.c | 54 | ||||
-rw-r--r-- | kernel/time/timekeeping.c | 7 |
3 files changed, 2 insertions, 63 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index f448513a45ed..feccfd888732 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -20,10 +20,6 @@ config GENERIC_TIME_VSYSCALL config GENERIC_TIME_VSYSCALL_OLD bool -# ktime_t scalar 64bit nsec representation -config KTIME_SCALAR - bool - # Old style timekeeping config ARCH_USES_GETTIMEOFFSET bool diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 2f4ef8a1e5ff..19f211051c35 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -261,60 +261,6 @@ lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags) * too large for inlining: */ #if BITS_PER_LONG < 64 -# ifndef CONFIG_KTIME_SCALAR -/** - * ktime_add_ns - Add a scalar nanoseconds value to a ktime_t variable - * @kt: addend - * @nsec: the scalar nsec value to add - * - * Returns the sum of kt and nsec in ktime_t format - */ -ktime_t ktime_add_ns(const ktime_t kt, u64 nsec) -{ - ktime_t tmp; - - if (likely(nsec < NSEC_PER_SEC)) { - tmp.tv64 = nsec; - } else { - unsigned long rem = do_div(nsec, NSEC_PER_SEC); - - /* Make sure nsec fits into long */ - if (unlikely(nsec > KTIME_SEC_MAX)) - return (ktime_t){ .tv64 = KTIME_MAX }; - - tmp = ktime_set((long)nsec, rem); - } - - return ktime_add(kt, tmp); -} - -EXPORT_SYMBOL_GPL(ktime_add_ns); - -/** - * ktime_sub_ns - Subtract a scalar nanoseconds value from a ktime_t variable - * @kt: minuend - * @nsec: the scalar nsec value to subtract - * - * Returns the subtraction of @nsec from @kt in ktime_t format - */ -ktime_t ktime_sub_ns(const ktime_t kt, u64 nsec) -{ - ktime_t tmp; - - if (likely(nsec < NSEC_PER_SEC)) { - tmp.tv64 = nsec; - } else { - unsigned long rem = do_div(nsec, NSEC_PER_SEC); - - tmp = ktime_set((long)nsec, rem); - } - - return ktime_sub(kt, tmp); -} - -EXPORT_SYMBOL_GPL(ktime_sub_ns); -# endif /* !CONFIG_KTIME_SCALAR */ - /* * Divide a ktime value by a nanosecond value */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index b94fa3652aaa..cafef242d8f9 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -344,11 +344,8 @@ ktime_t ktime_get(void) nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec; } while (read_seqcount_retry(&timekeeper_seq, seq)); - /* - * Use ktime_set/ktime_add_ns to create a proper ktime on - * 32-bit architectures without CONFIG_KTIME_SCALAR. - */ - return ktime_add_ns(ktime_set(secs, 0), nsecs); + + return ktime_set(secs, nsecs); } EXPORT_SYMBOL_GPL(ktime_get); |