Chris Snook wrote:
From: Chris Snook <[EMAIL PROTECTED]>

Make atomic_read() volatile on frv.  This ensures that busy-waiting
for an interrupt handler to change an atomic_t won't get compiled to an
infinite loop, consistent with SMP architectures.

To head off the criticism, I admit this is an oversimplification, and true busy-waiters should be using cpu_relax(), which contains a barrier. As discussed in recent threads, there are other cases which can be optimized by removing the need for a barrier, and having behavior consistent with architectures where the benefit is more profound is also valuable.

        -- Chris
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