linux-toradex.git/Documentation/memory-barriers.txt, branch v5.6-rc2

smp_mb__{before,after}_atomic(): update Documentation

2020-02-04T03:05:23+00:00

When adding the _{acquire|release|relaxed}() variants of some atomic
operations, it was forgotten to update Documentation/memory_barrier.txt:

smp_mb__{before,after}_atomic() is now intended for all RMW operations
that do not imply a memory barrier.

1)
	smp_mb__before_atomic();
	atomic_add();

2)
	smp_mb__before_atomic();
	atomic_xchg_relaxed();

3)
	smp_mb__before_atomic();
	atomic_fetch_add_relaxed();

Invalid would be:
	smp_mb__before_atomic();
	atomic_set();

In addition, the patch splits the long sentence into multiple shorter
sentences.

Link: http://lkml.kernel.org/r/20191020123305.14715-2-manfred@colorfullife.com
Fixes: 654672d4ba1a ("locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations")
Signed-off-by: Manfred Spraul 
Acked-by: Waiman Long 
Cc: Davidlohr Bueso 
Cc: Peter Zijlstra 
Cc: Will Deacon 
Cc: Peter Zijlstra 
Cc: <1vier1@web.de>
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

docs/memory-barriers.txt: Remove remaining references to mmiowb()

2019-11-22T17:00:46+00:00

This commit removes references to sections erased by Commit 915530396c78
("Documentation: Kill all references to mmiowb()").

Signed-off-by: SeongJae Park 
Link: https://lore.kernel.org/r/20191121234125.28032-6-sj38.park@gmail.com
Signed-off-by: Jonathan Corbet

docs: fix broken doc references due to renames

2019-07-17T09:57:51+00:00

Some files got renamed but probably due to some merge conflicts,
a few references still point to the old locations.

Signed-off-by: Mauro Carvalho Chehab

Merge tag 'docs-5.3' of git://git.lwn.net/linux

2019-07-09T19:34:26+00:00

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...

docs: pci: fix broken links due to conversion from pci.txt to pci.rst

2019-06-08T19:42:37+00:00

Some documentation files were still pointing to the old place.

Fixes: 229b4e0728e0 ("Documentation: PCI: convert pci.txt to reST")
Signed-off-by: Mauro Carvalho Chehab 
Acked-by: Paul E. McKenney 
Signed-off-by: Jonathan Corbet

doc: Remove ".vnet" from paulmck email addresses

2019-05-28T16:02:57+00:00

Signed-off-by: Paul E. McKenney

docs/memory-barriers.txt: Update I/O section to be clearer about CPU vs thread

2019-04-23T12:34:17+00:00

The revised I/O ordering section of memory-barriers.txt introduced in
4614bbdee357 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER
EFFECTS" section") loosely refers to "the CPU", whereas the ordering
guarantees generally apply within a thread of execution that can migrate
between cores, with the scheduler providing the relevant barrier
semantics.

Reword the section to refer to "CPU thread" and call out ordering of
MMIO writes separately from ordering of writes to memory. Ben also
spotted that the string accessors are native-endian, so fix that up too.

Link: https://lkml.kernel.org/r/080d1ec73e3e29d6ffeeeb50b39b613da28afb37.camel@kernel.crashing.org
Fixes: 4614bbdee357 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER EFFECTS" section")
Reported-by: Benjamin Herrenschmidt 
Signed-off-by: Will Deacon

docs/memory-barriers.txt: Fix style, spacing and grammar in I/O section

2019-04-11T11:02:40+00:00

Commit 4614bbdee357 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O
BARRIER EFFECTS" section") rewrote the I/O ordering section of
memory-barriers.txt.

Subsequently, Ingo noticed a number of issues with the style, spacing
and grammar of the rewritten section. Fix them based on his suggestions.

Link: https://lkml.kernel.org/r/20190410105833.GA116161@gmail.com
Fixes: 4614bbdee357 ("docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER EFFECTS" section")
Reported-by: Ingo Molnar 
Acked-by: Ingo Molnar 
Signed-off-by: Will Deacon

Documentation: Kill all references to mmiowb()

2019-04-08T11:00:45+00:00

The guarantees provided by mmiowb() are now provided implicitly by
spin_unlock(), so remove all references to this most confusing of
barriers from our Documentation.

Good riddance.

Acked-by: Linus Torvalds 
Signed-off-by: Will Deacon

docs/memory-barriers.txt: Rewrite "KERNEL I/O BARRIER EFFECTS" section

2019-04-08T10:59:30+00:00

The "KERNEL I/O BARRIER EFFECTS" section of memory-barriers.txt is vague,
x86-centric, out-of-date, incomplete and demonstrably incorrect in places.
This is largely because I/O ordering is a horrible can of worms, but also
because the document has stagnated as our understanding has evolved.

Attempt to address some of that, by rewriting the section based on
recent(-ish) discussions with Arnd, BenH and others. Maybe one day we'll
find a way to formalise this stuff, but for now let's at least try to
make the English easier to understand.

Cc: Benjamin Herrenschmidt 
Cc: Michael Ellerman 
Cc: Arnd Bergmann 
Cc: Peter Zijlstra 
Cc: Andrea Parri 
Cc: Palmer Dabbelt 
Cc: Daniel Lustig 
Cc: David Howells 
Cc: Alan Stern 
Cc: "Maciej W. Rozycki" 
Cc: Mikulas Patocka 
Acked-by: Linus Torvalds 
Reviewed-by: Paul E. McKenney 
Signed-off-by: Will Deacon