Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly mark

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718

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Merge ^/head r357931 through r357965.

Consolidate read code for timecounters and fix possible overflow in
bintime()/binuptime().

The algorithm to read the consistent snapshot of current timehand is
repeated in each accessor, including t

Consolidate read code for timecounters and fix possible overflow in
bintime()/binuptime().

The algorithm to read the consistent snapshot of current timehand is
repeated in each accessor, including the details proper rollup
detection and synchronization with the writer. In fact there are only
two different kind of readers: one for bintime()/binuptime() which has
to do the in-place calculation, and another kind which fetches some
member from struct timehand.

Extract the logic into type-checked macros, GETTHBINTIME() for bintime
calculation, and GETTHMEMBER() for safe read of a structure' member.
This way, the synchronization is only written in bintime_off() and
getthmember().

In bintime_off(), use overflow-safe calculation of th_scale *
delta(timecounter). In tc_windup, pre-calculate the min delta value
which overflows and require slow algorithm, into the new timehands
th_large_delta member.

This part with overflow fix was written by Bruce Evans.

Reported by: Mark Millard <marklmi@yahoo.com> (the overflow issue)
Tested by: pho
Discussed with: emaste
Sponsored by: The FreeBSD Foundation (kib)
MFC after: 3 weeks

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Merge ^/head r357270 through r357349.

Remove duplicated empty lines from kern/*.c

No functional changes.

Merge ^/head r351732 through r352104.

Initialize timehands linkage much earlier.

Reported and tested by: trasz
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

Make timehands count selectable at boottime.

Tested by: O'Connor, Daniel <darius@dons.net.au>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.or

Make timehands count selectable at boottime.

Tested by: O'Connor, Daniel <darius@dons.net.au>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D21563

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Instead of using an incomplete list of platforms that uses 64bits time_t
in 32bits mode, special case amd64, as i386 is the only arch that still
uses 32bits time_t.

MFH @ r337607, in preparation for boarding

Merge ^/head r336870 through r337285, and resolve conflicts.

Make timespecadd(3) and friends public

The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have

Make timespecadd(3) and friends public

The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.

Our kernel currently defines two-argument versions of timespecadd and
timespecsub. NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions. Solaris also defines a three-argument version, but
only in its kernel. This revision changes our definition to match the
common three-argument version.

Bump _FreeBSD_version due to the breaking KPI change.

Discussed with: cem, jilles, ian, bde
Differential Revision: https://reviews.freebsd.org/D14725

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Create a new macro for static DPCPU data.

On arm64 (and possible other architectures) we are unable to use static
DPCPU data in kernel modules. This is because the compiler will generate
PC-relative

Create a new macro for static DPCPU data.

On arm64 (and possible other architectures) we are unable to use static
DPCPU data in kernel modules. This is because the compiler will generate
PC-relative accesses, however the runtime-linker expects to be able to
relocate these.

In preparation to fix this create two macros depending on if the data is
global or static.

Reviewed by: bz, emaste, markj
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D16140

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tc: bcopy -> memcpy

Move most of the contents of opt_compat.h to opt_global.h.

opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
close

Move most of the contents of opt_compat.h to opt_global.h.

opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.

Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.

Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.

Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941

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Merge ^/head r326936 through r327149.

Use atomic_load(9) to read ppsinfo sequence numbers.

In this case volatile qualifiers enusre that a compiler does not
optimize the accesses out.

Reviewed by: alc, jhb
Sponsored by: The FreeBSD Foun

Use atomic_load(9) to read ppsinfo sequence numbers.

In this case volatile qualifiers enusre that a compiler does not
optimize the accesses out.

Reviewed by: alc, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D13534

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SPDX: use the Beerware identifier.

Merge ^/head r323559 through r325504.

MFhead@r324837

While here, diff reduce some of the changes in sys/boot by moving
MK_COVERAGE=no to sys/boot/Makefile.inc .

The th_bintime, th_microtime and th_nanotime members of the timehand
all cache the last system time (uptime + boottime). Only the format
differs. Do not re-calculate the bintime and simply use the

The th_bintime, th_microtime and th_nanotime members of the timehand
all cache the last system time (uptime + boottime). Only the format
differs. Do not re-calculate the bintime and simply use the value
used to calculate the microtime and nanotime.

Group all the updates under the relevant comment. Remove obsoleted
XXX part.

Submitted by: Sebastian Huber <sebastian.huber@embedded-brains.de>
MFC after: 1 week

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Add missing pieces of r315280

I moved this branch from github to a private server, and pulled from the
wrong one when committing r315280, so I failed to include two recent commits.
Thankfully, they

Add missing pieces of r315280

I moved this branch from github to a private server, and pulled from the
wrong one when committing r315280, so I failed to include two recent commits.
Thankfully, they were only cosmetic and were included in the review.
Specifically:

Add documentation, polish comments, and improve style(9).

Tested by: pho (r315280)
MFC after: 2 weeks
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D9791

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When the RTC is adjusted, reevaluate absolute sleep times based on the RTC

POSIX 2008 says this about clock_settime(2):

If the value of the CLOCK_REALTIME clock is set via clock_settime(),

When the RTC is adjusted, reevaluate absolute sleep times based on the RTC

POSIX 2008 says this about clock_settime(2):

If the value of the CLOCK_REALTIME clock is set via clock_settime(),
the new value of the clock shall be used to determine the time
of expiration for absolute time services based upon the
CLOCK_REALTIME clock. This applies to the time at which armed
absolute timers expire. If the absolute time requested at the
invocation of such a time service is before the new value of
the clock, the time service shall expire immediately as if the
clock had reached the requested time normally.

Setting the value of the CLOCK_REALTIME clock via clock_settime()
shall have no effect on threads that are blocked waiting for
a relative time service based upon this clock, including the
nanosleep() function; nor on the expiration of relative timers
based upon this clock. Consequently, these time services shall
expire when the requested relative interval elapses, independently
of the new or old value of the clock.

When the real-time clock is adjusted, such as by clock_settime(3),
wake any threads sleeping until an absolute real-clock time.
Such a sleep is indicated by a non-zero td_rtcgen. The sleep functions
will set that field to zero and return zero to tell the caller
to reevaluate its sleep duration based on the new value of the clock.

At present, this affects the following functions:

pthread_cond_timedwait(3)
pthread_mutex_timedlock(3)
pthread_rwlock_timedrdlock(3)
pthread_rwlock_timedwrlock(3)
sem_timedwait(3)
sem_clockwait_np(3)

I'm working on adding clock_nanosleep(2), which will also be affected.

Reported by: Sebastian Huber <sebastian.huber@embedded-brains.de>
Reviewed by: jhb, kib
MFC after: 2 weeks
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D9791

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Merge ^/head r309817 through r310168.

Add labels to sysctls related to clocks.

Sysctls like kern.eventtimer.et.*.quality currently embed the name of
the clock device. This is problematic for the Prometheus metrics
exporter for two reaso

Add labels to sysctls related to clocks.

Sysctls like kern.eventtimer.et.*.quality currently embed the name of
the clock device. This is problematic for the Prometheus metrics
exporter for two reasons:

- Some of those clocks have dashes in their names, which Prometheus
doesn't allow to be used in metric names.
- It doesn't allow for extracting the same property of all clocks on the
system from within a single query.

Attach these nodes to have a label, so that the Prometheus metrics
exporter gives these metric a uniform name with the name of the clock
attached as a label.

Reviewed by: cem
Differential Revision: https://reviews.freebsd.org/D8775

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