Re: seperator error in __mask_snprintf_len

[Andi Kleen]

> >  static inline void bitmap_complement(unsigned long *bitmap, int bits)
> >  {
> >         int k;
> > +       int max = BITS_TO_LONGS(bits);
> >  
> > -       for (k = 0; k < BITS_TO_LONGS(bits); ++k)
> > +       for (k = 0; k < max; ++k)
> >                 bitmap[k] = ~bitmap[k];
> 
> OK.  bitmap_and() and bitmap_or() were converted to this form a while back
> because they too were hitting the bug.  On ia32.  It might no longer
> happen now they're uninlined but whatever - you don't have to look
> at the code and think "gee, I hope the compiler moves that arith out
> of the loop".

BTW I think the original point of the inlining was that when you have bits ==
BITS_PER_LONG the function could collapse to a single ~ operation using
the compiler's optimizer. That would be the case with nodemasks on x86-64. 
As for the NUMA API i don't care particularly because there is no bitmap 
manipulation in any fast path. Avoiding miscompilations is definitely 
higher priority. 

-Andi
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