Re: delay_tsc(): inefficient delay loop (2.6.16-mm1)

• To: "Andreas Mohr" <[email protected]>
• Subject: Re: delay_tsc(): inefficient delay loop (2.6.16-mm1)
• From: "Ray Lee" <[email protected]>
• Date: Fri, 24 Mar 2006 09:22:51 -0800
• Cc: lkml <[email protected]>, "john stultz" <[email protected]>, "Dominik Brodowski" <[email protected]>
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On 3/24/06, Andreas Mohr <[email protected]> wrote:
> +       loops += bclock;
[...]
> -       } while ((now-bclock) < loops);
> +       } while (now < loops);

Erm, aren't you introducing an overflow problem here?

if loops is 2^32-1, bclock is 1, the old version would execute the
proper number of times, the new one will blow out in one tick.
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