manuals: Misc syntax fixes

These were reported by `mandoc -T lint ...` as errors.

Signed-off-by: Graham Percival <gperciva@tarsnap.com>
Reviewed by: mhorne
MFC after: 3 days
Sponsored by: Tarsnap B

manuals: Misc syntax fixes

These were reported by `mandoc -T lint ...` as errors.

Signed-off-by: Graham Percival <gperciva@tarsnap.com>
Reviewed by: mhorne
MFC after: 3 days
Sponsored by: Tarsnap Backup Inc.
Pull Request: https://github.com/freebsd/freebsd-src/pull/1453

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Remove my middle name.

Remove $FreeBSD$: two-line nroff pattern

Remove /^\.\\"\n\.\\"\s*\$FreeBSD\$$\n/

man9: Add an smr(9) manual page

Also update the UMA manual page to mention its SMR-enabled
functionality, and update locking.9 to mention both epoch and SMR.
Details of its usage are provided in the

man9: Add an smr(9) manual page

Also update the UMA manual page to mention its SMR-enabled
functionality, and update locking.9 to mention both epoch and SMR.
Details of its usage are provided in the SMR manual page.

Reviewed by: Olivier Certner, mhorne, kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D38108

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uma: correct prototype in the documentation

uma: Add UMA_ZONE_UNMANAGED

Allow a zone to opt out of cache size management. In particular,
uma_reclaim() and uma_reclaim_domain() will not reclaim any memory from
the zone, nor will uma_timeout()

uma: Add UMA_ZONE_UNMANAGED

Allow a zone to opt out of cache size management. In particular,
uma_reclaim() and uma_reclaim_domain() will not reclaim any memory from
the zone, nor will uma_timeout() purge cached items if the zone is idle.
This effectively means that the zone consumer has control over when
items are reclaimed from the cache. In particular, uma_zone_reclaim()
will still reclaim cached items from an unmanaged zone.

Reviewed by: hselasky, kib
MFC after: 3 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34142

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zone.9: Remove documentation of non-existent NUMA configuration flags

These configuration options were removed in commit dfe13344f557.

Some forthcoming work will update the UMA man page to describe

zone.9: Remove documentation of non-existent NUMA configuration flags

These configuration options were removed in commit dfe13344f557.

Some forthcoming work will update the UMA man page to describe its
current behaviour on NUMA systems.

MFC after: 1 week
Sponsored by: The FreeBSD Foundation

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The zone(9) man page had two entries for uma_reclaim(), one with
an argument (correct), and one without (incorrect). Pointed out
by Allan Jude.

uma: Introduce per-domain reclamation functions

Make it possible to reclaim items from a specific NUMA domain.

- Add uma_zone_reclaim_domain() and uma_reclaim_domain().
- Permit parallel reclamatio

uma: Introduce per-domain reclamation functions

Make it possible to reclaim items from a specific NUMA domain.

- Add uma_zone_reclaim_domain() and uma_reclaim_domain().
- Permit parallel reclamations. Use a counter instead of a flag to
synchronize with zone_dtor().
- Use the zone lock to protect cache_shrink() now that parallel reclaims
can happen.
- Add a sysctl that can be used to trigger reclamation from a specific
domain.

Currently the new KPIs are unused, so there should be no functional
change.

Reviewed by: mav
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D29685

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Document that uma_zfree_pcpu() allows NULL now

While here also document that for counter_u64_free().

Reviewed by: rpokala@
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")
Di

Document that uma_zfree_pcpu() allows NULL now

While here also document that for counter_u64_free().

Reviewed by: rpokala@
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D29215

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MFH

Sponsored by: Rubicon Communications, LLC (netgate.com)

Fix function name in zone.9

uma_zone_prealloc -> uma_prealloc. There's no uma_zone_prealloc defined and the
docs for it describe uma_prealloc exactly.

MFH

Sponsored by: Rubicon Communications, LLC (netgate.com)

Merge ^/head r363739 through r363986.

Remove free_domain() and uma_zfree_domain().

These functions were introduced before UMA started ensuring that freed
memory gets placed in domain-local caches. They no longer serve any
purpose since

Remove free_domain() and uma_zfree_domain().

These functions were introduced before UMA started ensuring that freed
memory gets placed in domain-local caches. They no longer serve any
purpose since UMA now provides their functionality by default. Remove
them to simplyify the kernel memory allocator interfaces a bit.

Reviewed by: cem, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25937

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Merge ^/head r357408 through r357661.

uma: add UMA_ZONE_CONTIG, and a default contig_alloc

For now, copy the mbuf allocator.

Reviewed by: jeff, markj (previous version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://revie

uma: add UMA_ZONE_CONTIG, and a default contig_alloc

For now, copy the mbuf allocator.

Reviewed by: jeff, markj (previous version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D23237

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uma: reorganize flags

- Garbage collect UMA_ZONE_PAGEABLE & UMA_ZONE_STATIC.
- Move flag VTOSLAB from public to private.
- Introduce public NOTPAGE flag and make HASH private.
- Introduce public

uma: reorganize flags

- Garbage collect UMA_ZONE_PAGEABLE & UMA_ZONE_STATIC.
- Move flag VTOSLAB from public to private.
- Introduce public NOTPAGE flag and make HASH private.
- Introduce public NOTOUCH flag and make OFFPAGE private.
- Update man page.

The net effect of this should be to make the contract with clients more
clear. Clients should choose constraints, UMA will figure out how to
implement them. This also breaks the confusing double meaning of
OFFPAGE.

Reviewed by: jeff, markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D23016

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Revise the page cache size policy.

In r353734 the use of the page caches was limited to systems with a
relatively large amount of RAM per CPU. This was to mitigate some
issues reported with the sys

Revise the page cache size policy.

In r353734 the use of the page caches was limited to systems with a
relatively large amount of RAM per CPU. This was to mitigate some
issues reported with the system not able to keep up with memory pressure
in cases where it had been able to do so prior to the addition of the
direct free pool cache. This change re-enables those caches.

The change modifies uma_zone_set_maxcache(), which was introduced
specifically for the page cache zones. Rather than using it to limit
only the full bucket cache, have it also set uz_count_max to provide an
upper bound on the per-CPU cache size that is consistent with the number
of items requested. Remove its return value since it has no use.

Enable the page cache zones unconditionally, and limit them to 0.1% of
the domain's pages. The limit can be overridden by the
vm.pgcache_zone_max tunable as before.

Change the item size parameter passed to uma_zcache_create() to the
correct size, and stop setting UMA_ZONE_MAXBUCKET. This allows the page
cache buckets to be adaptively sized, like the rest of UMA's caches.
This also causes the initial bucket size to be small, so only systems
which benefit from large caches will get them.

Reviewed by: gallatin, jeff
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D22393

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Merge ^/head r351317 through r351731.

Extend uma_reclaim() to permit different reclamation targets.

The page daemon periodically invokes uma_reclaim() to reclaim cached
items from each zone when the system is under memory pressure. Thi

Extend uma_reclaim() to permit different reclamation targets.

The page daemon periodically invokes uma_reclaim() to reclaim cached
items from each zone when the system is under memory pressure. This
is important since the size of these caches is unbounded by default.
However it also results in bursts of high latency when allocating from
heavily used zones as threads miss in the per-CPU caches and must
access the keg in order to allocate new items.

With r340405 we maintain an estimate of each zone's usage of its
(per-NUMA domain) cache of full buckets. Start making use of this
estimate to avoid reclaiming the entire cache when under memory
pressure. In particular, introduce TRIM, DRAIN and DRAIN_CPU
verbs for uma_reclaim() and uma_zone_reclaim(). When trimming, only
items in excess of the estimate are reclaimed. Draining a zone
reclaims all of the cached full buckets (the previous behaviour of
uma_reclaim()), and may further drain the per-CPU caches in extreme
cases.

Now, when under memory pressure, the page daemon will trim zones
rather than draining them. As a result, heavily used zones do not incur
bursts of bucket cache misses following reclamation, but large, unused
caches will be reclaimed as before.

Reviewed by: jeff
Tested by: pho (an earlier version)
MFC after: 2 months
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D16667

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Update and clean up the UMA man page.

- Fix warnings from igor and mandoc.
- Provide a brief description of the separation between zones and their
backend slab allocators.
- Document cache zones a

Update and clean up the UMA man page.

- Fix warnings from igor and mandoc.
- Provide a brief description of the separation between zones and their
backend slab allocators.
- Document cache zones and secondary zones.
- Document the kernel config options added in r350659.
- Document the uma_zalloc_pcpu() and uma_zfree_pcpu() wrappers.
- Document uma_zone_reserve(), uma_zone_reserve_kva() and
uma_zone_prealloc().
- Document uma_zone_alloc() and uma_zone_freef().
- Add some missing MLINKs and Xrefs.

MFC after: 2 weeks

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Make UMA and malloc(9) return non-executable memory in most cases.

Most kernel memory that is allocated after boot does not need to be
executable. There are a few exceptions. For example, kernel m

Make UMA and malloc(9) return non-executable memory in most cases.

Most kernel memory that is allocated after boot does not need to be
executable. There are a few exceptions. For example, kernel modules
do need executable memory, but they don't use UMA or malloc(9). The
BPF JIT compiler also needs executable memory and did use malloc(9)
until r317072.

(Note that a side effect of r316767 was that the "small allocation"
path in UMA on amd64 already returned non-executable memory. This
meant that some calls to malloc(9) or the UMA zone(9) allocator could
return executable memory, while others could return non-executable
memory. This change makes the behavior consistent.)

This change makes malloc(9) return non-executable memory unless the new
M_EXEC flag is specified. After this change, the UMA zone(9) allocator
will always return non-executable memory, and a KASSERT will catch
attempts to use the M_EXEC flag to allocate executable memory using
uma_zalloc() or its variants.

Allocations that do need executable memory have various choices. They
may use the M_EXEC flag to malloc(9), or they may use a different VM
interfact to obtain executable pages.

Now that malloc(9) again allows executable allocations, this change also
reverts most of r317072.

PR: 228927
Reviewed by: alc, kib, markj, jhb (previous version)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D15691

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Document new NUMA related syscalls and utility options.

Sponsored by: Netflix, Dell/EMC Isilon

Fix formatting errors that resulted in apropos(1) output looking weird.

MFC after: 2 weeks