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SubjectRe: (*(unsigned long *)&jiffies)++;
Andrea Arcangeli wrote:
>
> > movl foo,%eax ! Get it
> > leal 1(%eax),%edx ! bump it by one
> > movl %edx,foo ! write it back
>
> The above is perfect for a volatile variable IMHO. Also incl (without lock
> on the bus) is not atomic in SMP.

AFAIK incl _lock_ the bus even without "lock" in fornt of the
instruction
on 386 machine. Or at least i386 instruction set manual say so.
But there is no word about all this in the newest manual i got from
Intel.
Is this changed on i[56]86?


Petkan

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