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-rw-r--r--Documentation/memory-barriers.txt11
1 files changed, 3 insertions, 8 deletions
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 1adbb8a371c7..ec3b5865c1be 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -63,7 +63,6 @@ CONTENTS
- Compiler barrier.
- CPU memory barriers.
- - MMIO write barrier.
(*) Implicit kernel memory barriers.
@@ -75,7 +74,6 @@ CONTENTS
(*) Inter-CPU acquiring barrier effects.
- Acquires vs memory accesses.
- - Acquires vs I/O accesses.
(*) Where are memory barriers needed?
@@ -492,10 +490,9 @@ And a couple of implicit varieties:
happen before it completes.
The use of ACQUIRE and RELEASE operations generally precludes the need
- for other sorts of memory barrier (but note the exceptions mentioned in
- the subsection "MMIO write barrier"). In addition, a RELEASE+ACQUIRE
- pair is -not- guaranteed to act as a full memory barrier. However, after
- an ACQUIRE on a given variable, all memory accesses preceding any prior
+ for other sorts of memory barrier. In addition, a RELEASE+ACQUIRE pair is
+ -not- guaranteed to act as a full memory barrier. However, after an
+ ACQUIRE on a given variable, all memory accesses preceding any prior
RELEASE on that same variable are guaranteed to be visible. In other
words, within a given variable's critical section, all accesses of all
previous critical sections for that variable are guaranteed to have
@@ -1512,8 +1509,6 @@ levels:
(*) CPU memory barriers.
- (*) MMIO write barrier.
-
COMPILER BARRIER
----------------