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Date: Fri, 11 Jan 2008 14:57:47 -0800
From: "Vineet Gupta" <vineetg76@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: Usage semantics of atomic_set ( )
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I'm trying to implement atomic ops for a CPU which has no inherent
support for Read-Modify-Write Ops. Instead of using a global spin lock
which protects all the atomic APIs, I want to use a spin lock per
instance of atomic_t. This works well when atomic_t is unitary and
statically initialized using ATOMIC_INIT (where I can reset the
spinlock_t as well). However if atomic_t var is embedded within a
bigger struct which is allocated dynamically how to I init the
embedded spin lock. atomic_set ( ) is the closest choice, however I
don't think it's current usage in kernel code qualifies it to be
"initializer only".

Doesn't that defeat the intended usage of atomic_t as a opaque type
which can be "effectively" used to hide other architecture specific
stuff.

Thanks,
Vineet