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Date: Thu, 31 Jul 2003 16:16:57 +0530
From: Raj Inguva <rajsk@in.ibm.com>
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To: Kirill Korotaev <kksx@mail.ru>
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Subject: Re: atomic_set & gcc. atomicity question
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> #define atomic_set(v,i)         (((v)->counter) = (i))

'v' is of type atomic_t which is a structure.

> If we call atomic_set() with constant 2nd argument it's ok - it's a > simple write to var. But what if we do atomic_set(var, var1+var2)?

It will expand to (((var)->counter) = (var1+var2))

'counter' is 'volatile' .