At this point, we have converted most of the kernel to use timespec64 consistently in place of timespec, so it seems it's time to make timespec64 the native structure and define timespec in terms of that one on 64-bit architectures.

Starting with gcc-5, the compiler can completely optimize away the timespec_to_timespec64 and timespec64_to_timespec functions on 64-bit architectures. With older compilers, we introduce a couple of extra copies of local variables, but those are easily avoided by using the timespec64 based interfaces consistently, as we do in most of the important code paths already.

The main upside of removing the hack is that printing the tv_sec field of a timespec64 structure can now use the %lld format string on all architectures without a cast to time64_t. Without this patch, the field is a 'long' type and would have to be printed using %ld on 64-bit architectures.

Signed-off-by: Arnd Bergmann arnd@arndb.de --- include/linux/time32.h | 18 +++-------------- include/linux/time64.h | 7 ------- include/linux/timekeeping32.h | 45 ------------------------------------------- kernel/time/time.c | 2 -- 4 files changed, 3 insertions(+), 69 deletions(-)

diff --git a/include/linux/time32.h b/include/linux/time32.h index d2bcd4377b56..0b14f936100a 100644 --- a/include/linux/time32.h +++ b/include/linux/time32.h @@ -18,25 +18,14 @@ /* timespec64 is defined as timespec here */ static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64) { - return ts64; + return *(const struct timespec *)&ts64; }

static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) { - return ts; + return *(const struct timespec64 *)&ts; }

-# define timespec_equal timespec64_equal -# define timespec_compare timespec64_compare -# define set_normalized_timespec set_normalized_timespec64 -# define timespec_add timespec64_add -# define timespec_sub timespec64_sub -# define timespec_valid timespec64_valid -# define timespec_valid_strict timespec64_valid_strict -# define timespec_to_ns timespec64_to_ns -# define ns_to_timespec ns_to_timespec64 -# define timespec_add_ns timespec64_add_ns - #else static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64) { @@ -55,6 +44,7 @@ static inline struct timespec64 timespec_to_timespec64(const struct timespec ts) ret.tv_nsec = ts.tv_nsec; return ret; } +#endif

static inline int timespec_equal(const struct timespec *a, const struct timespec *b) @@ -159,8 +149,6 @@ static __always_inline void timespec_add_ns(struct timespec *a, u64 ns) a->tv_nsec = ns; }

-#endif - /** * time_to_tm - converts the calendar time to local broken-down time * diff --git a/include/linux/time64.h b/include/linux/time64.h index 0d96887ba4e0..0a7b2f79cec7 100644 --- a/include/linux/time64.h +++ b/include/linux/time64.h @@ -16,11 +16,6 @@ typedef __u64 timeu64_t;

#include <uapi/linux/time.h>

-#if __BITS_PER_LONG == 64 -/* this trick allows us to optimize out timespec64_to_timespec */ -# define timespec64 timespec -#define itimerspec64 itimerspec -#else struct timespec64 { time64_t tv_sec; /* seconds */ long tv_nsec; /* nanoseconds */ @@ -31,8 +26,6 @@ struct itimerspec64 { struct timespec64 it_value; };

-#endif - /* Parameters used to convert the timespec values: */ #define MSEC_PER_SEC 1000L #define USEC_PER_MSEC 1000L diff --git a/include/linux/timekeeping32.h b/include/linux/timekeeping32.h index 3616b4becb59..4ea45d0df1d4 100644 --- a/include/linux/timekeeping32.h +++ b/include/linux/timekeeping32.h @@ -16,50 +16,6 @@ static inline struct timespec current_kernel_time(void) return timespec64_to_timespec(now); }

-#if BITS_PER_LONG == 64 -/** - * Deprecated. Use do_settimeofday64(). - */ -static inline int do_settimeofday(const struct timespec *ts) -{ - return do_settimeofday64(ts); -} - -static inline int __getnstimeofday(struct timespec *ts) -{ - return __getnstimeofday64(ts); -} - -static inline void getnstimeofday(struct timespec *ts) -{ - getnstimeofday64(ts); -} - -static inline void ktime_get_ts(struct timespec *ts) -{ - ktime_get_ts64(ts); -} - -static inline void ktime_get_real_ts(struct timespec *ts) -{ - getnstimeofday64(ts); -} - -static inline void getrawmonotonic(struct timespec *ts) -{ - getrawmonotonic64(ts); -} - -static inline struct timespec get_monotonic_coarse(void) -{ - return get_monotonic_coarse64(); -} - -static inline void getboottime(struct timespec *ts) -{ - return getboottime64(ts); -} -#else /** * Deprecated. Use do_settimeofday64(). */ @@ -124,7 +80,6 @@ static inline void getboottime(struct timespec *ts) getboottime64(&ts64); *ts = timespec64_to_timespec(ts64); } -#endif

/* * Timespec interfaces utilizing the ktime based ones diff --git a/kernel/time/time.c b/kernel/time/time.c index 3ddf10b6523c..8e4f3fd2f84b 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -407,7 +407,6 @@ time64_t mktime64(const unsigned int year0, const unsigned int mon0, } EXPORT_SYMBOL(mktime64);

-#if __BITS_PER_LONG == 32 /** * set_normalized_timespec - set timespec sec and nsec parts and normalize * @@ -468,7 +467,6 @@ struct timespec ns_to_timespec(const s64 nsec) return ts; } EXPORT_SYMBOL(ns_to_timespec); -#endif

/** * ns_to_timeval - Convert nanoseconds to timeval

In a move to make ktime_get_*() the preferred driver interface into the timekeeping code, sanitizes ktime_get_real_ts64() to be a proper exported symbol rather than an alias for getnstimeofday64().

The internal __getnstimeofday64() is no longer used, so remove that and merge it into ktime_get_real_ts64().

Signed-off-by: Arnd Bergmann arnd@arndb.de --- include/linux/timekeeping.h | 8 +++++--- include/linux/timekeeping32.h | 13 ++----------- kernel/time/timekeeping.c | 31 ++++++------------------------- 3 files changed, 13 insertions(+), 39 deletions(-)

diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 588a0e4b1ab9..415dae6bf1f5 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -30,15 +30,13 @@ struct timespec64 current_kernel_time64(void); struct timespec64 get_monotonic_coarse64(void); extern void getrawmonotonic64(struct timespec64 *ts); extern void ktime_get_ts64(struct timespec64 *ts); +extern void ktime_get_real_ts64(struct timespec64 *tv); extern time64_t ktime_get_seconds(void); extern time64_t __ktime_get_real_seconds(void); extern time64_t ktime_get_real_seconds(void);

-extern int __getnstimeofday64(struct timespec64 *tv); -extern void getnstimeofday64(struct timespec64 *tv); extern void getboottime64(struct timespec64 *ts);

-#define ktime_get_real_ts64(ts) getnstimeofday64(ts)

/* * ktime_t based interfaces @@ -210,5 +208,9 @@ extern void read_persistent_clock64(struct timespec64 *ts); extern void read_boot_clock64(struct timespec64 *ts); extern int update_persistent_clock64(struct timespec64 now);

+/* + * deprecated aliases, don't use in new code + */ +#define getnstimeofday64(ts) ktime_get_real_ts64(ts)

#endif diff --git a/include/linux/timekeeping32.h b/include/linux/timekeeping32.h index 4ea45d0df1d4..5abff52d07fd 100644 --- a/include/linux/timekeeping32.h +++ b/include/linux/timekeeping32.h @@ -27,20 +27,11 @@ static inline int do_settimeofday(const struct timespec *ts) return do_settimeofday64(&ts64); }

-static inline int __getnstimeofday(struct timespec *ts) -{ - struct timespec64 ts64; - int ret = __getnstimeofday64(&ts64); - - *ts = timespec64_to_timespec(ts64); - return ret; -} - static inline void getnstimeofday(struct timespec *ts) { struct timespec64 ts64;

- getnstimeofday64(&ts64); + ktime_get_real_ts64(&ts64); *ts = timespec64_to_timespec(ts64); }

@@ -56,7 +47,7 @@ static inline void ktime_get_real_ts(struct timespec *ts) { struct timespec64 ts64;

- getnstimeofday64(&ts64); + ktime_get_real_ts64(&ts64); *ts = timespec64_to_timespec(ts64); }

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 49cbceef5deb..7bbc7a6e6095 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -705,18 +705,19 @@ static void timekeeping_forward_now(struct timekeeper *tk) }

/** - * __getnstimeofday64 - Returns the time of day in a timespec64. + * ktime_get_real_ts64 - Returns the time of day in a timespec64. * @ts: pointer to the timespec to be set * - * Updates the time of day in the timespec. - * Returns 0 on success, or -ve when suspended (timespec will be undefined). + * Returns the time of day in a timespec64 (WARN if suspended). */ -int __getnstimeofday64(struct timespec64 *ts) +void ktime_get_real_ts64(struct timespec64 *ts) { struct timekeeper *tk = &tk_core.timekeeper; unsigned long seq; u64 nsecs;

+ WARN_ON(timekeeping_suspended); + do { seq = read_seqcount_begin(&tk_core.seq);

@@ -727,28 +728,8 @@ int __getnstimeofday64(struct timespec64 *ts)

ts->tv_nsec = 0; timespec64_add_ns(ts, nsecs); - - /* - * Do not bail out early, in case there were callers still using - * the value, even in the face of the WARN_ON. - */ - if (unlikely(timekeeping_suspended)) - return -EAGAIN; - return 0; -} -EXPORT_SYMBOL(__getnstimeofday64); - -/** - * getnstimeofday64 - Returns the time of day in a timespec64. - * @ts: pointer to the timespec64 to be set - * - * Returns the time of day in a timespec64 (WARN if suspended). - */ -void getnstimeofday64(struct timespec64 *ts) -{ - WARN_ON(__getnstimeofday64(ts)); } -EXPORT_SYMBOL(getnstimeofday64); +EXPORT_SYMBOL(ktime_get_real_ts64);

ktime_t ktime_get(void) {

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 --- include/linux/timekeeping.h | 16 ++++++++++++++++ kernel/time/timekeeping.c | 19 +++++++++++++++++++ 2 files changed, 35 insertions(+)

diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 3ef9791d7d75..42f71f4b658a 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -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 */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index ed9b74ec9c0b..4786df904c22 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -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.