Adrian Hunter d0304569fb clocksource: Make watchdog and suspend-timing multiplication overflow safe ...

Kernel timekeeping is designed to keep the change in cycles (since the last
timer interrupt) below max_cycles, which prevents multiplication overflow
when converting cycles to nanoseconds. However, if timer interrupts stop,
the clocksource_cyc2ns() calculation will eventually overflow.

Add protection against that. Simplify by folding together
clocksource_delta() and clocksource_cyc2ns() into cycles_to_nsec_safe().
Check against max_cycles, falling back to a slower higher precision
calculation.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240325064023.2997-20-adrian.hunter@intel.com

2024-04-08 15:03:08 +02:00

..

alarmtimer.c

rtc: class: make rtc_class constant

2024-03-08 12:05:10 +01:00

clockevents.c

clockevents: Make clockevents_subsys const

2024-02-07 15:11:24 +01:00

clocksource-wdtest.c

clocksource: Scale the watchdog read retries automatically

2024-02-21 12:00:42 +01:00

clocksource.c

clocksource: Make watchdog and suspend-timing multiplication overflow safe

2024-04-08 15:03:08 +02:00

hrtimer.c

hrtimer: Remove unused function

2024-04-08 15:03:06 +02:00

itimer.c

…

jiffies.c

clocksource: Make clocksource watchdog test safe for slow-HZ systems

2021-08-28 17:01:32 +02:00

Kconfig

sched/idle: Conditionally handle tick broadcast in default_idle_call()

2024-03-01 21:04:27 +01:00

Makefile

timers: Implement the hierarchical pull model

2024-02-22 17:52:32 +01:00

namespace.c

vdso/timens: Refactor copy-pasted find_timens_vvar_page() helper into one copy

2022-12-01 11:35:40 +01:00

ntp_internal.h

…

ntp.c

…

posix-clock.c

Fix memory leak in posix_clock_open()

2024-03-27 09:03:22 -07:00

posix-cpu-timers.c

posix-cpu-timers: Implement the missing timer_wait_running callback

2023-04-21 15:34:33 +02:00

posix-stubs.c

posix-timers: Get rid of [COMPAT_]SYS_NI() uses

2023-12-20 21:30:27 -08:00

posix-timers.c

posix-timers: Refer properly to CONFIG_HIGH_RES_TIMERS

2023-06-18 22:41:53 +02:00

posix-timers.h

…

sched_clock.c

time/sched_clock: Provide sched_clock_noinstr()

2023-06-05 21:11:04 +02:00

test_udelay.c

time/debug: Fix memory leak with using debugfs_lookup()

2023-02-09 20:12:27 +01:00

tick-broadcast-hrtimer.c

time/tick-broadcast: Remove RCU_NONIDLE() usage

2023-01-13 11:48:16 +01:00

tick-broadcast.c

tick/broadcast: Make broadcast device replacement work correctly

2023-05-08 23:18:16 +02:00

tick-common.c

tick: Assume timekeeping is correctly handed over upon last offline idle call

2024-02-26 11:37:32 +01:00

tick-internal.h

tick: Move broadcast cancellation up to CPUHP_AP_TICK_DYING

2024-02-26 11:37:32 +01:00

tick-legacy.c

…

tick-oneshot.c

time: Fix various kernel-doc problems

2023-01-03 11:07:58 +01:00

tick-sched.c

tick/sched: Fix various kernel-doc warnings

2024-04-01 10:36:35 +02:00

tick-sched.h

tick/sched: Fix struct tick_sched doc warnings

2024-04-01 10:36:35 +02:00

time_test.c

time: test: Fix incorrect format specifier

2024-02-27 15:26:08 -07:00

time.c

time: add kernel-doc in time.c

2023-07-14 13:47:07 -06:00

timeconst.bc

…

timeconv.c

time: Improve performance of time64_to_tm()

2021-06-24 11:51:59 +02:00

timecounter.c

time/timecounter: Mark 1st argument of timecounter_cyc2time() as const

2021-04-16 21:03:50 +02:00

timekeeping_debug.c

…

timekeeping_internal.h

…

timekeeping.c

timekeeping: Let timekeeping_cycles_to_ns() handle both under and overflow

2024-04-08 15:03:08 +02:00

timekeeping.h

…

timer_list.c

tick: Split nohz and highres features from nohz_mode

2024-02-26 11:37:32 +01:00

timer_migration.c

timers/migration: Return early on deactivation

2024-04-05 11:05:16 +02:00

timer_migration.h

timers: Implement the hierarchical pull model

2024-02-22 17:52:32 +01:00

timer.c

timers: Fix text inconsistencies and spelling

2024-04-01 10:36:35 +02:00

vsyscall.c

vdso: Add vdso_data:: Max_cycles

2024-04-08 15:03:07 +02:00