Messages in this thread | | | Subject | Re: [PATCH] Add minimal support for software performance counters for ia64 | From | Peter Zijlstra <> | Date | Wed, 19 Aug 2009 18:12:31 +0200 |
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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.
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