clock: Add a long ticks variable, ticksl

For compatibility with Linux, it's useful to have a tick counter of
width sizeof(long), but our tick counter is an int. Currently the
linuxkpi tries paper o

clock: Add a long ticks variable, ticksl

For compatibility with Linux, it's useful to have a tick counter of
width sizeof(long), but our tick counter is an int. Currently the
linuxkpi tries paper over this difference, but this cannot really be
done reliably, so it's desirable to have a wider tick counter. This
change introduces ticksl, keeping the existing ticks variable.

Follow a suggestion from kib to avoid having to maintain two separate
counters and to avoid converting existing code to use ticksl: change
hardclock() to update ticksl instead of ticks, and then use assembler
directives to make ticks and ticksl overlap such that loading ticks
gives the bottom 32 bits. This makes it possible to use ticksl in the
linuxkpi without having to convert any native code, and without making
hardclock() more complicated or expensive. Then, the linuxkpi can be
modified to use ticksl instead of ticks.

Reviewed by: olce, kib, emaste
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D48383

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cred: 'kern.ngroups' tunable: Limit it to avoid internal overflows

As the comment introduced with the tunable said (but the code didn't
do), make sure that 'ngroups_max' can't be INT_MAX, as this wo

cred: 'kern.ngroups' tunable: Limit it to avoid internal overflows

As the comment introduced with the tunable said (but the code didn't
do), make sure that 'ngroups_max' can't be INT_MAX, as this would cause
overflow in the usual 'ngroups_max + 1' computations (as we store the
effective GID and supplementary groups' IDs in the same array, and
'ngroups_max' only applies to supplementary groups).

Further, we limit the maximum number of groups somewhat arbitrarily to
~17M so as to avoid overflow when computing the size in bytes of the
groups set's backing array and to avoid obvious configuration errors.
We really don't think that more than ~17M groups will ever be needed (if
I'm proven wrong one day, please drop me a note about your use case).

While here, document more precisely why NGROUPS_MAX needs to be the
minimum value for 'ngroups_max'.

Reviewed by: mhorne (older version)
Approved by: markj (mentor)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D46913

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x86: Detect NVMM hypervisor

MFC after: 1 week

Fix new users of MAXPHYS and hide it from the kernel namespace

In cd8537910406, kib made maxphys a load-time tunable. This made
the #define MAXPHYS in sys/param.h almost entirely obsolete, as
it c

Fix new users of MAXPHYS and hide it from the kernel namespace

In cd8537910406, kib made maxphys a load-time tunable. This made
the #define MAXPHYS in sys/param.h almost entirely obsolete, as
it could now be overridden by kern.maxphys at boot time, or by
opt_maxphys.h.

However, decades of tradition have led to several new, incorrect, uses
of MAXPHYS in other parts of the kernel, mostly by seasoned
developers. I've corrected those uses here in a mechanical fashion,
and verified that it fixes a bug in the md driver that I was
experiencing.

Since using MAXPHYS is such an easy mistake to make, it is best to
hide it from the kernel namespace. So I've moved its definition to
_maxphys.h, which is now included in param.h only for userspace.

That brings up the fact that lots of userspace programs use MAXPHYS
for different reasons, most of them probably wrong. Userspace consumers
that really need to know the value of maxphys should probably be
changed to use the kern.maxphys sysctl. But that's outside the scope
of this change.

Reviewed by: imp, jkim, kib, markj
Fixes: 30038a8b4efc ("md: Get rid of the pbuf zone")
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D44986

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Rename VM_LAST to more appropriate VM_GUEST_LAST

NFC

Sponsored by: Rubicon Communications, LLC ("Netgate")

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl s

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

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Fix up the vm_guest_sysctl_names size assert.

As VM_LAST was included in the array, the size check had to always pass.

While here modernize the assert itself.

Sponsored by: Rubicon Communications,

Fix up the vm_guest_sysctl_names size assert.

As VM_LAST was included in the array, the size check had to always pass.

While here modernize the assert itself.

Sponsored by: Rubicon Communications, LLC ("Netgate")

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arm64: do not disable the kern.kstack_pages tunable on arm64

Add a comment explaining what is not quite correct with arm64 and riscv.

Reviewed by: jhb, markj
Sponsored by: The FreeBSD Foundation
MF

arm64: do not disable the kern.kstack_pages tunable on arm64

Add a comment explaining what is not quite correct with arm64 and riscv.

Reviewed by: jhb, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D42143

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sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Revert "Revert "tslog: Annotate some early boot functions""

Now that <sys/tslog.h> is wrapped in #ifdef _KERNEL, it's safe to have
tslog annotations in files which might be built from userland (i.e.

Revert "Revert "tslog: Annotate some early boot functions""

Now that <sys/tslog.h> is wrapped in #ifdef _KERNEL, it's safe to have
tslog annotations in files which might be built from userland (i.e. in
subr_boot.c, which is built as part of the boot loader).

This reverts commit 59588a546f55523d6fd37ab42eb08b719311d7d6.

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Revert "tslog: Annotate some early boot functions"

The change to subr_boot.c broke the libsa build because the TSLOG
macros have their own definitions for the boot loader -- I didn't
realize that th

Revert "tslog: Annotate some early boot functions"

The change to subr_boot.c broke the libsa build because the TSLOG
macros have their own definitions for the boot loader -- I didn't
realize that the loader code used subr_boot.c.

I'm currently testing a fix and I'll revert this revert once I'm
satisfied that everything works, but I don't want to leave the
tree broken for too long.

This reverts commit 469cfa3c30ee7a5ddeb597d0a8c3e7cac909b27a.

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tslog: Annotate some early boot functions

Booting an amd64 kernel on Firecracker with 1 CPU and 128 MB of RAM,
hammer_time takes roughly 2740 us:
* 55 us in xen_pvh_parse_preload_data
* 20 us in b

tslog: Annotate some early boot functions

Booting an amd64 kernel on Firecracker with 1 CPU and 128 MB of RAM,
hammer_time takes roughly 2740 us:
* 55 us in xen_pvh_parse_preload_data
* 20 us in boot_parse_cmdline_delim
* 20 us in boot_env_to_howto
* 15 us in identify_hypervisor
* 1320 us in link_elf_reloc
* 1310 us in relocate_file1 handling ef->rela
* 25 us in init_param1
* 30 us in dpcpu_init
* 355 us in initializecpu
* 255 us in initializecpu calling load_cr4
* 425 us in getmemsize
* 280 us in pmap_bootstrap
* 205 us in create_pagetables
* 10 us in init_param2
* 25 us in pci_early_quirks
* 60 us in cninit
* 90 us in kdb_init
* 105 us in msgbufinit
* 20 us in fpuinit
* 205 us elsewhere in hammer_time

Some of these are unavoidable (e.g. identify_hypervisor uses CPUID and
load_cr4 loads the CR4 register, both of which trap to the hypervisor)
but others may deserve attention.

Sponsored by: https://www.patreon.com/cperciva
Differential Revision: https://reviews.freebsd.org/D40325

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kern: whack __mips__ leftover

Sponsored by: Rubicon Communications, LLC ("Netgate")

time(3): Optimize tvtohz() function.

List of changes:
- Use integer multiplication instead of long multiplication, because the result is an integer.
- Remove multiple if-statements and predict new i

time(3): Optimize tvtohz() function.

List of changes:
- Use integer multiplication instead of long multiplication, because the result is an integer.
- Remove multiple if-statements and predict new if-statements.
- Rename local variable name, "ticks" into "retval" to avoid shadowing
the system "ticks" global variable.

Reviewed by: kib@ and imp@
MFC after: 1 week
Sponsored by: NVIDIA Networking
Differential Revision: https://reviews.freebsd.org/D36859

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time(3): Declare the minimum and maximum hz values supported.

Reviewed by: kib@ and imp@
MFC after: 1 week
Sponsored by: NVIDIA Networking
Differential Revision: https://reviews.freebsd.org/D

time(3): Declare the minimum and maximum hz values supported.

Reviewed by: kib@ and imp@
MFC after: 1 week
Sponsored by: NVIDIA Networking
Differential Revision: https://reviews.freebsd.org/D37072

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kern: Fix a typo in asource code comment

- s/overriden/overridden/

MFC after: 3 days

Move mips and arm to 1000Hz by default.

armv6 and armv7 systems already were 1000Hz. The other armv5 were a
mix of 100 and 1000. This changes them to 1000. Should there be
issues, we can add options

Move mips and arm to 1000Hz by default.

armv6 and armv7 systems already were 1000Hz. The other armv5 were a
mix of 100 and 1000. This changes them to 1000. Should there be
issues, we can add options HZ=100 to the systems that have bad
performance at the drop of a hat.

mips is a lot more complicated. But most of the systems are already
1000HZ. The hardware exceptions are all fast enough to run at
1000Hz. MALTA is our primary emulator, and history has shown emulators
tend to like 100Hz better, so run those systems at 100Hz. As with arm,
any system that shows a huge performance regression can reverted to
100Hz easily.

This was going to be committed well in advance of the 13 branch, but
it was delayed and forgotten til now.

Discussed on: #bsdmips ages ago
Sponsored by: Netflix

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Make MAXPHYS tunable. Bump MAXPHYS to 1M.

Replace MAXPHYS by runtime variable maxphys. It is initialized from
MAXPHYS by default, but can be also adjusted with the tunable kern.maxphys.

Make b_pag

Make MAXPHYS tunable. Bump MAXPHYS to 1M.

Replace MAXPHYS by runtime variable maxphys. It is initialized from
MAXPHYS by default, but can be also adjusted with the tunable kern.maxphys.

Make b_pages[] array in struct buf flexible. Size b_pages[] for buffer
cache buffers exactly to atop(maxbcachebuf) (currently it is sized to
atop(MAXPHYS)), and b_pages[] for pbufs is sized to atop(maxphys) + 1.
The +1 for pbufs allow several pbuf consumers, among them vmapbuf(),
to use unaligned buffers still sized to maxphys, esp. when such
buffers come from userspace (*). Overall, we save significant amount
of otherwise wasted memory in b_pages[] for buffer cache buffers,
while bumping MAXPHYS to desired high value.

Eliminate all direct uses of the MAXPHYS constant in kernel and driver
sources, except a place which initialize maxphys. Some random (and
arguably weird) uses of MAXPHYS, e.g. in linuxolator, are converted
straight. Some drivers, which use MAXPHYS to size embeded structures,
get private MAXPHYS-like constant; their convertion is out of scope
for this work.

Changes to cam/, dev/ahci, dev/ata, dev/mpr, dev/mpt, dev/mvs,
dev/siis, where either submitted by, or based on changes by mav.

Suggested by: mav (*)
Reviewed by: imp, mav, imp, mckusick, scottl (intermediate versions)
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D27225

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Make max ticks for pause in vn_lock_pair() adjustable at runtime.

Reduce default value from hz / 10 to hz / 100.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation

Merge ^/head r358269 through r358399.

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 r357408 through r357661.

Remove sparc64 kernel support

Remove all sparc64 specific files
Remove all sparc64 ifdefs
Removee indireeect sparc64 ifdefs

riscv: restore default HZ=1000, keep QEMU at HZ=100

This reverts r351918 and r351919.

Discussed with: br, ian, imp

riscv: default to HZ=100

Most current RISC-V development platforms are not fast enough to benefit
from the increased granularity provided by HZ=1000.

Sponsored by: Axiado