From: Pavel Machek <pavel@suse.cz>
To: kernel list <linux-kernel@vger.kernel.org>,
Andrew Morton <akpm@osdl.org>,
mtk.manpages@gmail.com, rdunlap@xenotime.net,
linux-doc@vger.kernel.org
Subject: atomics: document that linux expects certain atomic behaviour from unsigned long
Date: Sat, 3 Jan 2009 13:44:00 +0100 [thread overview]
Message-ID: <20090103124400.GA1572@ucw.cz> (raw)
Linux relies on unsigned long to behave like atomic for read/write.
diff --git a/Documentation/atomic_ops.txt b/Documentation/atomic_ops.txt
index 4ef2450..0a7d180 100644
--- a/Documentation/atomic_ops.txt
+++ b/Documentation/atomic_ops.txt
@@ -21,6 +21,9 @@ local_t is very similar to atomic_t. If the counter is per CPU and only
updated by one CPU, local_t is probably more appropriate. Please see
Documentation/local_ops.txt for the semantics of local_t.
+unsigned long can be used instead of atomic_t, if all you
+need is atomic setting and atomic reading.
+
The first operations to implement for atomic_t's are the initializers and
plain reads.
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
next reply other threads:[~2009-01-03 20:10 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-03 12:44 Pavel Machek [this message]
2009-01-03 20:19 ` atomics: document that linux expects certain atomic behaviour from unsigned long Alan Cox
2009-01-03 20:27 ` Pavel Machek
2009-01-03 20:30 ` Alan Cox
2009-01-03 20:56 ` Pavel Machek
2009-01-03 23:01 ` david
2009-01-03 23:14 ` Alan Cox
2009-01-05 10:54 ` Nick Piggin
2009-01-05 11:23 ` Alan Cox
2009-01-05 12:00 ` Nick Piggin
2009-01-05 16:05 ` Paul E. McKenney
2009-01-05 16:25 ` Nick Piggin
2009-01-05 17:30 ` Paul E. McKenney
2009-01-05 18:25 ` Nick Piggin
2009-01-05 22:01 ` Paul E. McKenney
2009-01-03 23:53 ` Robert Hancock
2009-01-04 18:05 ` Tilman Schmidt
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