On Thu, Aug 16, 2007 at 06:28:42AM +0530, Satyam Sharma wrote:

quoted

The udelay itself certainly should have some form of cpu_relax in it.

Yes, a form of barrier() must be present in mdelay() or udelay() itself
as you say, having it in __const_udelay() is *not* enough (superflous
actually, considering it is already a separate translation unit and
invisible to the compiler).

As long as __const_udelay does something which has the same
effect as barrier it is enough even if it's in the same unit.
As a matter of fact it does on i386 where __delay either uses
rep_nop or asm/volatile.

Cheers,
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