mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-08-05 00:34:52 +00:00
ab407a1919
This pull request contains the following:
o Improvements to clocksource-watchdog console messages.
o Loosening of the clocksource-watchdog skew criteria to match
those of NTP (500 parts per million, relaxed from 400 parts
per million). If it is good enough for NTP, it is good enough
for the clocksource watchdog.
o Suspend clocksource-watchdog checking temporarily when high
memory latencies are detected. This avoids the false-positive
clock-skew events that have been seen on production systems
running memory-intensive workloads.
o On systems where the TSC is deemed trustworthy, use it as the
watchdog timesource, but only when specifically requested using
the tsc=watchdog kernel boot parameter. This permits clock-skew
events to be detected, but avoids forcing workloads to use the
slow HPET and ACPI PM timers. These last two timers are slow
enough to cause systems to be needlessly marked bad on the one
hand, and real skew does sometimes happen on production systems
running production workloads on the other. And sometimes it is
the fault of the TSC, or at least of the firmware that told the
kernel to program the TSC with the wrong frequency.
o Add a tsc=revalidate kernel boot parameter to allow the kernel
to diagnose cases where the TSC hardware works fine, but was told
by firmware to tick at the wrong frequency. Such cases are rare,
but they really have happened on production systems.
-----BEGIN PGP SIGNATURE-----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=OWY2
-----END PGP SIGNATURE-----
Merge tag 'clocksource.2023.02.06b' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into timers/core
Pull clocksource watchdog changes from Paul McKenney:
o Improvements to clocksource-watchdog console messages.
o Loosening of the clocksource-watchdog skew criteria to match
those of NTP (500 parts per million, relaxed from 400 parts
per million). If it is good enough for NTP, it is good enough
for the clocksource watchdog.
o Suspend clocksource-watchdog checking temporarily when high
memory latencies are detected. This avoids the false-positive
clock-skew events that have been seen on production systems
running memory-intensive workloads.
o On systems where the TSC is deemed trustworthy, use it as the
watchdog timesource, but only when specifically requested using
the tsc=watchdog kernel boot parameter. This permits clock-skew
events to be detected, but avoids forcing workloads to use the
slow HPET and ACPI PM timers. These last two timers are slow
enough to cause systems to be needlessly marked bad on the one
hand, and real skew does sometimes happen on production systems
running production workloads on the other. And sometimes it is
the fault of the TSC, or at least of the firmware that told the
kernel to program the TSC with the wrong frequency.
o Add a tsc=revalidate kernel boot parameter to allow the kernel
to diagnose cases where the TSC hardware works fine, but was told
by firmware to tick at the wrong frequency. Such cases are rare,
but they really have happened on production systems.
Link: https://lore.kernel.org/r/20230210193640.GA3325193@paulmck-ThinkPad-P17-Gen-1
|
||
|---|---|---|
| .. | ||
| alarmtimer.c | ||
| clockevents.c | ||
| clocksource-wdtest.c | ||
| clocksource.c | ||
| hrtimer.c | ||
| itimer.c | ||
| jiffies.c | ||
| Kconfig | ||
| Makefile | ||
| namespace.c | ||
| ntp.c | ||
| ntp_internal.h | ||
| posix-clock.c | ||
| posix-cpu-timers.c | ||
| posix-stubs.c | ||
| posix-timers.c | ||
| posix-timers.h | ||
| sched_clock.c | ||
| test_udelay.c | ||
| tick-broadcast-hrtimer.c | ||
| tick-broadcast.c | ||
| tick-common.c | ||
| tick-internal.h | ||
| tick-legacy.c | ||
| tick-oneshot.c | ||
| tick-sched.c | ||
| tick-sched.h | ||
| time.c | ||
| time_test.c | ||
| timeconst.bc | ||
| timeconv.c | ||
| timecounter.c | ||
| timekeeping.c | ||
| timekeeping.h | ||
| timekeeping_debug.c | ||
| timekeeping_internal.h | ||
| timer.c | ||
| timer_list.c | ||
| vsyscall.c | ||