Peter Zijlstra wrote:
> On Wed, 2009-08-19 at 12:04 -0400, William Cohen wrote:
>> +#ifdef __ia64__
>> +#include "../../arch/ia64/include/asm/unistd.h"
>> +#define rmb()          asm volatile("" ::: "memory")
>> +#define cpu_relax()    asm volatile("" ::: "memory");
>> +#endif
> 
> Surely the itanic has a real memory barrier? The kernel seems to use
> something along the lines of mf.
> 
> Also, cpu_relax() seems to end up being asm volatile("hint @pause" :::
> "memory"), although we don't seem to have an actual user of cpu_relax()
> in perf atm.
> 
> 
> 

Peter, thanks for the comment. I took a look at the rmb() and cpu_relax() code
in the kernel and revised the patch with the appropriate defines

-Will