Messages in this thread | | | Date | Fri, 24 Mar 2006 18:37:42 +0100 | From | Edgar Toernig <> | Subject | Re: delay_tsc(): inefficient delay loop (2.6.16-mm1) |
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Andreas Mohr wrote: > > rdtscl(bclock); > + /* offset with bclock to have very simple comparison below */ > + loops += bclock; > do { > rep_nop(); > rdtscl(now); > - } while ((now-bclock) < loops); > + } while (now < loops); > }
Hehe, optimizing delay loops *g* But your optimization is wrong. 'loops+bclock' and/or 'now' is likely to wrap around and then the test condition becomes bogus.
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