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Date: Sun, 22 Dec 2002 00:36:32 -0500
From: Joshua Stewart <joshua.stewart@comcast.net>
Subject: A little explanation needed
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Can anyone explain the purpose of this #define...

#define __cpu_raise_softirq(cpu, nr) do { softirq_pending(cpu) |= 1UL <<
(nr); } while (0)    // from interrupt.h

...versus the more "plain"...


#define __cpu_raise_softirq(cpu,nr) softirq_pending(cpu |= 1UL << (nr).

In otherwords, what's the use of a do{X}while(0) "loop" instead of just
X.  I'm not the world's best trained C programmer, so forgive me if I
sound stupid.

Josh


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