Re: [PATCH 0/24] make atomic_read() behave consistently across allarchitectures
From: Christoph Lameter
Date: Tue Aug 14 2007 - 19:14:58 EST
On Tue, 14 Aug 2007, Chris Snook wrote:
> Because atomic operations are generally used for synchronization, which
> requires volatile behavior. Most such codepaths currently use an inefficient
> barrier(). Some forget to and we get bugs, because people assume that
> atomic_read() actually reads something, and atomic_write() actually writes
> something. Worse, these are architecture-specific, even compiler
> version-specific bugs that are often difficult to track down.
Looks like we need to have lock and unlock semantics?
atomic_read()
which has no barrier or volatile implications.
atomic_read_for_lock
Acquire semantics?
atomic_read_for_unlock
Release semantics?
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