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

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

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Link: https://lore.kernel.org/r/20191121234125.28032-6-sj38.park@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
SeongJae Park 2019-11-22 00:41:23 +01:00 committed by Jonathan Corbet
parent 3ef2f6aca5
commit a897b13d1b

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@ -63,7 +63,6 @@ CONTENTS
- Compiler barrier. - Compiler barrier.
- CPU memory barriers. - CPU memory barriers.
- MMIO write barrier.
(*) Implicit kernel memory barriers. (*) Implicit kernel memory barriers.
@ -75,7 +74,6 @@ CONTENTS
(*) Inter-CPU acquiring barrier effects. (*) Inter-CPU acquiring barrier effects.
- Acquires vs memory accesses. - Acquires vs memory accesses.
- Acquires vs I/O accesses.
(*) Where are memory barriers needed? (*) Where are memory barriers needed?
@ -492,10 +490,9 @@ And a couple of implicit varieties:
happen before it completes. happen before it completes.
The use of ACQUIRE and RELEASE operations generally precludes the need The use of ACQUIRE and RELEASE operations generally precludes the need
for other sorts of memory barrier (but note the exceptions mentioned in for other sorts of memory barrier. In addition, a RELEASE+ACQUIRE pair is
the subsection "MMIO write barrier"). In addition, a RELEASE+ACQUIRE -not- guaranteed to act as a full memory barrier. However, after an
pair is -not- guaranteed to act as a full memory barrier. However, after ACQUIRE on a given variable, all memory accesses preceding any prior
an ACQUIRE on a given variable, all memory accesses preceding any prior
RELEASE on that same variable are guaranteed to be visible. In other RELEASE on that same variable are guaranteed to be visible. In other
words, within a given variable's critical section, all accesses of all words, within a given variable's critical section, all accesses of all
previous critical sections for that variable are guaranteed to have previous critical sections for that variable are guaranteed to have
@ -1512,8 +1509,6 @@ levels:
(*) CPU memory barriers. (*) CPU memory barriers.
(*) MMIO write barrier.
COMPILER BARRIER COMPILER BARRIER
---------------- ----------------