diff options
author | 2019-12-03 12:20:25 -0800 | |
---|---|---|
committer | 2019-12-03 12:20:25 -0800 | |
commit | 043cf46825c102683b1027762c09c7e2b749e5a3 (patch) | |
tree | 765765d137ec75e6455d9e8fdc5a4ff94b1cf5e3 /kernel/time/time.c | |
parent | Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kerne... (diff) | |
parent | Merge branch 'timers/urgent' into timers/core, to pick up fix (diff) | |
download | linux-043cf46825c102683b1027762c09c7e2b749e5a3.tar.gz linux-043cf46825c102683b1027762c09c7e2b749e5a3.tar.bz2 linux-043cf46825c102683b1027762c09c7e2b749e5a3.zip |
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Ingo Molnar:
"The main changes in the timer code in this cycle were:
- Clockevent updates:
- timer-of framework cleanups. (Geert Uytterhoeven)
- Use timer-of for the renesas-ostm and the device name to prevent
name collision in case of multiple timers. (Geert Uytterhoeven)
- Check if there is an error after calling of_clk_get in asm9260
(Chuhong Yuan)
- ABI fix: Zero out high order bits of nanoseconds on compat
syscalls. This got broken a year ago, with apparently no side
effects so far.
Since the kernel would use random data otherwise I don't think we'd
have other options but to fix the bug, even if there was a side
effect to applications (Dmitry Safonov)
- Optimize ns_to_timespec64() on 32-bit systems: move away from
div_s64_rem() which can be slow, to div_u64_rem() which is faster
(Arnd Bergmann)
- Annotate KCSAN-reported false positive data races in
hrtimer_is_queued() users by moving timer->state handling over to
the READ_ONCE()/WRITE_ONCE() APIs. This documents these accesses
(Eric Dumazet)
- Misc cleanups and small fixes"
[ I undid the "ABI fix" and updated the comments instead. The reason
there were apparently no side effects is that the fix was a no-op.
The updated comment is to say _why_ it was a no-op. - Linus ]
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Zero the upper 32-bits in __kernel_timespec on 32-bit
time: Rename tsk->real_start_time to ->start_boottime
hrtimer: Remove the comment about not used HRTIMER_SOFTIRQ
time: Fix spelling mistake in comment
time: Optimize ns_to_timespec64()
hrtimer: Annotate lockless access to timer->state
clocksource/drivers/asm9260: Add a check for of_clk_get
clocksource/drivers/renesas-ostm: Use unique device name instead of ostm
clocksource/drivers/renesas-ostm: Convert to timer_of
clocksource/drivers/timer-of: Use unique device name instead of timer
clocksource/drivers/timer-of: Convert last full_name to %pOF
Diffstat (limited to 'kernel/time/time.c')
-rw-r--r-- | kernel/time/time.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/kernel/time/time.c b/kernel/time/time.c index 58e312e7380f..704ccd9451b0 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -179,7 +179,7 @@ int do_sys_settimeofday64(const struct timespec64 *tv, const struct timezone *tz return error; if (tz) { - /* Verify we're witin the +-15 hrs range */ + /* Verify we're within the +-15 hrs range */ if (tz->tz_minuteswest > 15*60 || tz->tz_minuteswest < -15*60) return -EINVAL; @@ -548,18 +548,21 @@ EXPORT_SYMBOL(set_normalized_timespec64); */ struct timespec64 ns_to_timespec64(const s64 nsec) { - struct timespec64 ts; + struct timespec64 ts = { 0, 0 }; s32 rem; - if (!nsec) - return (struct timespec64) {0, 0}; - - ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem); - if (unlikely(rem < 0)) { - ts.tv_sec--; - rem += NSEC_PER_SEC; + if (likely(nsec > 0)) { + ts.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem); + ts.tv_nsec = rem; + } else if (nsec < 0) { + /* + * With negative times, tv_sec points to the earlier + * second, and tv_nsec counts the nanoseconds since + * then, so tv_nsec is always a positive number. + */ + ts.tv_sec = -div_u64_rem(-nsec - 1, NSEC_PER_SEC, &rem) - 1; + ts.tv_nsec = NSEC_PER_SEC - rem - 1; } - ts.tv_nsec = rem; return ts; } @@ -878,10 +881,11 @@ int get_timespec64(struct timespec64 *ts, ts->tv_sec = kts.tv_sec; - /* Zero out the padding for 32 bit systems or in compat mode */ + /* Zero out the padding in compat mode */ if (in_compat_syscall()) kts.tv_nsec &= 0xFFFFFFFFUL; + /* In 32-bit mode, this drops the padding */ ts->tv_nsec = kts.tv_nsec; return 0; |