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Message-Id: <20200131205237.29535-6-sj38.park@gmail.com>
Date: Fri, 31 Jan 2020 21:52:37 +0100
From: SeongJae Park <sj38.park@...il.com>
To: corbet@....net, paulmck@...nel.org
Cc: SeongJae Park <sjpark@...zon.de>, linux-doc@...r.kernel.org,
linux-kernel@...r.kernel.org
Subject: [PATCH 5/5] Documentation/memory-barriers: Fix typos
From: SeongJae Park <sjpark@...zon.de>
Signed-off-by: SeongJae Park <sjpark@...zon.de>
---
Documentation/memory-barriers.txt | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index ec3b5865c1be..01ab5e22b670 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -185,7 +185,7 @@ As a further example, consider this sequence of events:
=============== ===============
{ A == 1, B == 2, C == 3, P == &A, Q == &C }
B = 4; Q = P;
- P = &B D = *Q;
+ P = &B; D = *Q;
There is an obvious data dependency here, as the value loaded into D depends on
the address retrieved from P by CPU 2. At the end of the sequence, any of the
@@ -569,7 +569,7 @@ following sequence of events:
{ A == 1, B == 2, C == 3, P == &A, Q == &C }
B = 4;
<write barrier>
- WRITE_ONCE(P, &B)
+ WRITE_ONCE(P, &B);
Q = READ_ONCE(P);
D = *Q;
@@ -1721,7 +1721,7 @@ of optimizations:
and WRITE_ONCE() are more selective: With READ_ONCE() and
WRITE_ONCE(), the compiler need only forget the contents of the
indicated memory locations, while with barrier() the compiler must
- discard the value of all memory locations that it has currented
+ discard the value of all memory locations that it has currently
cached in any machine registers. Of course, the compiler must also
respect the order in which the READ_ONCE()s and WRITE_ONCE()s occur,
though the CPU of course need not do so.
@@ -1833,7 +1833,7 @@ Aside: In the case of data dependencies, the compiler would be expected
to issue the loads in the correct order (eg. `a[b]` would have to load
the value of b before loading a[b]), however there is no guarantee in
the C specification that the compiler may not speculate the value of b
-(eg. is equal to 1) and load a before b (eg. tmp = a[1]; if (b != 1)
+(eg. is equal to 1) and load a[b] before b (eg. tmp = a[1]; if (b != 1)
tmp = a[b]; ). There is also the problem of a compiler reloading b after
having loaded a[b], thus having a newer copy of b than a[b]. A consensus
has not yet been reached about these problems, however the READ_ONCE()
--
2.17.1
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