linux-toradex.git/Documentation/core-api, branch v5.12-rc5

Merge branch 'akpm' (patches from Andrew)

2021-02-25T00:20:38+00:00

Merge misc updates from Andrew Morton:
 "A few small subsystems and some of MM.

  172 patches.

  Subsystems affected by this patch series: hexagon, scripts, ntfs,
  ocfs2, vfs, and mm (slab-generic, slab, slub, debug, pagecache, swap,
  memcg, pagemap, mprotect, mremap, page-reporting, vmalloc, kasan,
  pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
  mempolicy, oom-kill, hugetlbfs, and migration)"

* emailed patches from Andrew Morton : (172 commits)
  mm/migrate: remove unneeded semicolons
  hugetlbfs: remove unneeded return value of hugetlb_vmtruncate()
  hugetlbfs: fix some comment typos
  hugetlbfs: correct some obsolete comments about inode i_mutex
  hugetlbfs: make hugepage size conversion more readable
  hugetlbfs: remove meaningless variable avoid_reserve
  hugetlbfs: correct obsolete function name in hugetlbfs_read_iter()
  hugetlbfs: use helper macro default_hstate in init_hugetlbfs_fs
  hugetlbfs: remove useless BUG_ON(!inode) in hugetlbfs_setattr()
  hugetlbfs: remove special hugetlbfs_set_page_dirty()
  mm/hugetlb: change hugetlb_reserve_pages() to type bool
  mm, oom: fix a comment in dump_task()
  mm/mempolicy: use helper range_in_vma() in queue_pages_test_walk()
  numa balancing: migrate on fault among multiple bound nodes
  mm, compaction: make fast_isolate_freepages() stay within zone
  mm/compaction: fix misbehaviors of fast_find_migrateblock()
  mm/compaction: correct deferral logic for proactive compaction
  mm/compaction: remove duplicated VM_BUG_ON_PAGE !PageLocked
  mm/compaction: remove rcu_read_lock during page compaction
  z3fold: simplify the zhdr initialization code in init_z3fold_page()
  ...

mm/gfp: add kernel-doc for gfp_t

2021-02-24T21:38:32+00:00

The generated html will link to the definition of the gfp_t automatically
once we define it.  Move the one-paragraph overview of GFP flags from the
documentation directory into gfp.h and pull gfp.h into the documentation.

This generates warnings with clang
(https://lkml.kernel.org/r/20210219195509.GA59987@24bbad8f3778), so
use a #if 0 to hide it from the compiler for now.

Link: https://lkml.kernel.org/r/20210215204909.3824509-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20210220003049.GZ2858050@casper.infradead.org
Signed-off-by: Matthew Wilcox (Oracle) 
Acked-by: Mike Rapoport 
Cc: Nathan Chancellor 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: remove the {alloc,free}_noncoherent methods

2021-02-09T17:01:38+00:00

It turns out allowing non-contigous allocations here was a rather bad
idea, as we'll now need to define ways to get the pages for mmaping
or dma_buf sharing.  Revert this change and stick to the original
concept.  A different API for the use case of non-contigous allocations
will be added back later.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Tomasz Figa 
Tested-by: Ricardo Ribalda :wq

atomic: remove further references to atomic_ops

2020-12-31T22:51:33+00:00

Commit f0400a77ebdc ("atomic: Delete obsolete documentation") removed
./Documentation/core-api/atomic_ops.rst, but missed to remove further
references to that file.

Hence, make htmldocs warns:

  Documentation/core-api/index.rst:53: WARNING:
  toctree contains reference to nonexisting document 'core-api/atomic_ops'

Also, ./scripts/get_maintainer.pl --self-test=patterns warns:

  warning: no file matches    F:    Documentation/core-api/atomic_ops.rst

Remove further references to ./Documentation/core-api/atomic_ops.rst.

Fixes: f0400a77ebdc ("atomic: Delete obsolete documentation")
Signed-off-by: Lukas Bulwahn 
Link: https://lore.kernel.org/r/20201220060927.21582-1-lukas.bulwahn@gmail.com
Signed-off-by: Jonathan Corbet

Merge tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-12-15T23:03:31+00:00

Pull irq updates from Thomas Gleixner:
 "Generic interrupt and irqchips subsystem updates. Unusually, there is
  not a single completely new irq chip driver, just new DT bindings and
  extensions of existing drivers to accomodate new variants!

  Core:

   - Consolidation and robustness changes for irq time accounting

   - Cleanup and consolidation of irq stats

   - Remove the fasteoi IPI flow which has been proved useless

   - Provide an interface for converting legacy interrupt mechanism into
     irqdomains

  Drivers:

   - Preliminary support for managed interrupts on platform devices

   - Correctly identify allocation of MSIs proxyied by another device

   - Generalise the Ocelot support to new SoCs

   - Improve GICv4.1 vcpu entry, matching the corresponding KVM
     optimisation

   - Work around spurious interrupts on Qualcomm PDC

   - Random fixes and cleanups"

* tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling
  driver core: platform: Add devm_platform_get_irqs_affinity()
  ACPI: Drop acpi_dev_irqresource_disabled()
  resource: Add irqresource_disabled()
  genirq/affinity: Add irq_update_affinity_desc()
  irqchip/gic-v3-its: Flag device allocation as proxied if behind a PCI bridge
  irqchip/gic-v3-its: Tag ITS device as shared if allocating for a proxy device
  platform-msi: Track shared domain allocation
  irqchip/ti-sci-intr: Fix freeing of irqs
  irqchip/ti-sci-inta: Fix printing of inta id on probe success
  drivers/irqchip: Remove EZChip NPS interrupt controller
  Revert "genirq: Add fasteoi IPI flow"
  irqchip/hip04: Make IPIs use handle_percpu_devid_irq()
  irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq()
  irqchip/armada-370-xp: Make IPIs use handle_percpu_devid_irq()
  irqchip/gic, gic-v3: Make SGIs use handle_percpu_devid_irq()
  irqchip/ocelot: Add support for Jaguar2 platforms
  irqchip/ocelot: Add support for Serval platforms
  irqchip/ocelot: Add support for Luton platforms
  irqchip/ocelot: prepare to support more SoC
  ...

Merge branch 'akpm' (patches from Andrew)

2020-12-15T20:53:37+00:00

Merge misc updates from Andrew Morton:

 - a few random little subsystems

 - almost all of the MM patches which are staged ahead of linux-next
   material. I'll trickle to post-linux-next work in as the dependents
   get merged up.

Subsystems affected by this patch series: kthread, kbuild, ide, ntfs,
ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache,
gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation,
kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction,
oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc,
uaccess, zram, and cleanups).

* emailed patches from Andrew Morton : (200 commits)
  mm: cleanup kstrto*() usage
  mm: fix fall-through warnings for Clang
  mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at
  mm: shmem: convert shmem_enabled_show to use sysfs_emit_at
  mm:backing-dev: use sysfs_emit in macro defining functions
  mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening
  mm: use sysfs_emit for struct kobject * uses
  mm: fix kernel-doc markups
  zram: break the strict dependency from lzo
  zram: add stat to gather incompressible pages since zram set up
  zram: support page writeback
  mm/process_vm_access: remove redundant initialization of iov_r
  mm/zsmalloc.c: rework the list_add code in insert_zspage()
  mm/zswap: move to use crypto_acomp API for hardware acceleration
  mm/zswap: fix passing zero to 'PTR_ERR' warning
  mm/zswap: make struct kernel_param_ops definitions const
  userfaultfd/selftests: hint the test runner on required privilege
  userfaultfd/selftests: fix retval check for userfaultfd_open()
  userfaultfd/selftests: always dump something in modes
  userfaultfd: selftests: make __{s,u}64 format specifiers portable
  ...

selftests/vm: only some gup_test items are really benchmarks

2020-12-15T20:13:38+00:00

Therefore, some minor cleanup and improvements are in order:

1. Rename the other items appropriately.

2. Stop reporting timing information on the non-benchmark items. It's
   still being recorded and is available, but there's no point in
   cluttering up the report with data that no one reasonably needs to
   check.

3. Don't do iterations, for non-benchmark items.

4. Print out a shorter, more appropriate report for the non-benchmark
   tests.

5. Add the command that was run, to the report. This really helps, as
   there are quite a lot of options now.

6. Use a larger integer type for cmd, now that it's being compared
   Otherwise it doesn't work, because in this case cmd is about 3 billion,
   which is the perfect size for problems with signed vs unsigned int.

Link: https://lkml.kernel.org/r/20201026064021.3545418-6-jhubbard@nvidia.com
Signed-off-by: John Hubbard 
Cc: Jérôme Glisse 
Cc: Jonathan Corbet 
Cc: Ralph Campbell 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/gup_benchmark: rename to mm/gup_test

2020-12-15T20:13:38+00:00

Patch series "selftests/vm: gup_test, hmm-tests, assorted improvements", v3.

Summary: This series provides two main things, and a number of smaller
supporting goodies.  The two main points are:

1) Add a new sub-test to gup_test, which in turn is a renamed version
   of gup_benchmark.  This sub-test allows nicer testing of dump_pages(),
   at least on user-space pages.

   For quite a while, I was doing a quick hack to gup_test.c whenever I
   wanted to try out changes to dump_page().  Then Matthew Wilcox asked me
   what I meant when I said "I used my dump_page() unit test", and I
   realized that it might be nice to check in a polished up version of
   that.

   Details about how it works and how to use it are in the commit
   description for patch #6 ("selftests/vm: gup_test: introduce the
   dump_pages() sub-test").

2) Fixes a limitation of hmm-tests: these tests are incredibly useful,
   but only if people actually build and run them.  And it turns out that
   libhugetlbfs is a little too effective at throwing a wrench in the
   works, there.  So I've added a little configuration check that removes
   just two of the 21 hmm-tests, if libhugetlbfs is not available.

   Further details in the commit description of patch #8
   ("selftests/vm: hmm-tests: remove the libhugetlbfs dependency").

Other smaller things that this series does:

a) Remove code duplication by creating gup_test.h.

b) Clear up the sub-test organization, and their invocation within
   run_vmtests.sh.

c) Other minor assorted improvements.

[1] v2 is here:
https://lore.kernel.org/linux-doc/20200929212747.251804-1-jhubbard@nvidia.com/

[2] https://lore.kernel.org/r/CAHk-=wgh-TMPHLY3jueHX7Y2fWh3D+nMBqVS__AZm6-oorquWA@mail.gmail.com

This patch (of 9):

Rename nearly every "gup_benchmark" reference and file name to "gup_test".
The one exception is for the actual gup benchmark test itself.

The current code already does a *little* bit more than benchmarking, and
definitely covers more than get_user_pages_fast().  More importantly,
however, subsequent patches are about to add some functionality that is
non-benchmark related.

Closely related changes:

* Kconfig: in addition to renaming the options from GUP_BENCHMARK to
  GUP_TEST, update the help text to reflect that it's no longer a
  benchmark-only test.

Link: https://lkml.kernel.org/r/20201026064021.3545418-1-jhubbard@nvidia.com
Link: https://lkml.kernel.org/r/20201026064021.3545418-2-jhubbard@nvidia.com
Signed-off-by: John Hubbard 
Cc: Jonathan Corbet 
Cc: Jérôme Glisse 
Cc: Ralph Campbell 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: slab: provide krealloc_array()

2020-12-15T20:13:37+00:00

When allocating an array of elements, users should check for
multiplication overflow or preferably use one of the provided helpers
like: kmalloc_array().

There's no krealloc_array() counterpart but there are many users who use
regular krealloc() to reallocate arrays.  Let's provide an actual
krealloc_array() implementation.

While at it: add some documentation regarding krealloc.

Link: https://lkml.kernel.org/r/20201109110654.12547-3-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski 
Acked-by: Vlastimil Babka 
Cc: Alexander Shishkin 
Cc: Andy Shevchenko 
Cc: Borislav Petkov 
Cc: Borislav Petkov 
Cc: Christian Knig 
Cc: Christoph Lameter 
Cc: Daniel Vetter 
Cc: Daniel Vetter 
Cc: David Airlie 
Cc: David Rientjes 
Cc: Gustavo Padovan 
Cc: James Morse 
Cc: Jaroslav Kysela 
Cc: Jason Wang 
Cc: Joonsoo Kim 
Cc: Linus Walleij 
Cc: Maarten Lankhorst 
Cc: Mauro Carvalho Chehab 
Cc: Maxime Ripard 
Cc: "Michael S . Tsirkin" 
Cc: Pekka Enberg 
Cc: Robert Richter 
Cc: Sumit Semwal 
Cc: Takashi Iwai 
Cc: Takashi Iwai 
Cc: Thomas Zimmermann 
Cc: Tony Luck 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'locking-core-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-12-15T01:27:47+00:00

Pull locking updates from Thomas Gleixner:
 "A moderate set of locking updates:

   - A few extensions to the rwsem API and support for opportunistic
     spinning and lock stealing

   - lockdep selftest improvements

   - Documentation updates

   - Cleanups and small fixes all over the place"

* tag 'locking-core-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  seqlock: kernel-doc: Specify when preemption is automatically altered
  seqlock: Prefix internal seqcount_t-only macros with a "do_"
  Documentation: seqlock: s/LOCKTYPE/LOCKNAME/g
  locking/rwsem: Remove reader optimistic spinning
  locking/rwsem: Enable reader optimistic lock stealing
  locking/rwsem: Prevent potential lock starvation
  locking/rwsem: Pass the current atomic count to rwsem_down_read_slowpath()
  locking/rwsem: Fold __down_{read,write}*()
  locking/rwsem: Introduce rwsem_write_trylock()
  locking/rwsem: Better collate rwsem_read_trylock()
  rwsem: Implement down_read_interruptible
  rwsem: Implement down_read_killable_nested
  refcount: Fix a kernel-doc markup
  completion: Drop init_completion define
  atomic: Update MAINTAINERS
  atomic: Delete obsolete documentation
  seqlock: Rename __seqprop() users
  lockdep/selftest: Add spin_nest_lock test
  lockdep/selftests: Fix PROVE_RAW_LOCK_NESTING
  seqlock: avoid -Wshadow warnings
  ...