Geert Uytterhoeven
abcbcb80cd
time: Make sure jiffies_to_msecs() preserves non-zero time periods ...
For the common cases where 1000 is a multiple of HZ, or HZ is a multiple of
1000, jiffies_to_msecs() never returns zero when passed a non-zero time
period.
However, if HZ > 1000 and not an integer multiple of 1000 (e.g. 1024 or
1200, as used on alpha and DECstation), jiffies_to_msecs() may return zero
for small non-zero time periods. This may break code that relies on
receiving back a non-zero value.
jiffies_to_usecs() does not need such a fix: one jiffy can only be less
than one µs if HZ > 1000000, and such large values of HZ are already
rejected at build time, twice:
- include/linux/jiffies.h does #error if HZ >= 12288,
- kernel/time/time.c has BUILD_BUG_ON(HZ > USEC_PER_SEC).
Broken since forever.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-alpha@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180622143357.7495-1-geert@linux-m68k.org
2018-06-22 17:48:36 +02:00
alarmtimer: Init nanosleep alarm timer on stack
2018-03-29 16:10:07 +02:00
clockevents: Retry programming min delta up to 10 times
2017-10-19 16:29:15 +02:00
clocksource: Move inline keyword to the beginning of function declarations
2018-05-16 22:21:32 +02:00
posix-timers: Fix nanosleep_copyout() for CONFIG_COMPAT_32BIT_TIME
2018-06-19 09:23:19 +02:00
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSEC
2017-03-07 11:03:28 +01:00
sched/isolation: Eliminate NO_HZ_FULL_ALL
2018-02-15 15:40:37 -08:00
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
jiffies: Introduce USER_TICK_USEC and redefine TICK_USEC
2018-04-06 09:28:50 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-11-13 17:56:58 -08:00
vfs: do bulk POLL* -> EPOLL* replacement
2018-02-11 14:34:03 -08:00
posix-cpu-timers: Remove lockdep_assert_irqs_disabled()
2018-06-12 17:18:37 +02:00
Merge branch 'linus' into timers/2038
2018-05-19 13:55:40 +02:00
Merge branch 'linus' into timers/2038
2018-05-19 13:55:40 +02:00
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
timers, sched_clock: Update timeout for clock wrap
2017-03-23 12:30:27 -07:00
time: Avoid timespec in udelay_test
2016-06-20 12:47:26 -07:00
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
tick/broadcast: Use for_each_cpu() specially on UP kernels
2018-05-15 22:45:54 +02:00
Power management updates for 4.18-rc1
2018-06-05 09:38:39 -07:00
Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
2018-04-26 14:53:32 +02:00
clockevents: Fix kernel messages split across multiple lines
2018-04-17 17:18:04 +02:00
Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
2018-04-26 14:53:32 +02:00
nohz: Gather tick_sched booleans under a common flag field
2018-04-09 11:54:57 +02:00
time: Make sure jiffies_to_msecs() preserves non-zero time periods
2018-06-22 17:48:36 +02:00
time: Introduce jiffies64_to_nsecs()
2017-02-01 09:13:45 +01:00
time: Add time64_to_tm()
2016-06-20 12:47:15 -07:00
clocksource: Use a plain u64 instead of cycle_t
2016-12-25 11:04:12 +01:00
timekeeping: Add ktime_get_coarse_with_offset
2018-05-19 13:57:32 +02:00
Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
2018-04-26 14:53:32 +02:00
PM / timekeeping: Print debug messages when requested
2017-07-23 00:03:43 +02:00
kdb: use __ktime_get_real_seconds instead of __current_kernel_time
2018-01-25 08:40:18 -06:00
timers: Adjust a kernel-doc comment
2018-05-13 15:55:43 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-06-04 20:27:54 -07:00
abcbcb80cd