Messages in this thread | | | Date | Fri, 16 Nov 2007 08:17:08 +0100 | From | Ingo Molnar <> | Subject | Re: x86: disable preemption in delay_tsc() |
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* Andrew Morton <akpm@linux-foundation.org> wrote:
> It sounds like it would work OK. What is the setup cost for a usleep? > I'd have thought that code which does something like > > while (i++ < 1000) { > foo(); > udelay(1); > } > > would take qiute a bit longer with such a change?
full roundtrip cost ought to be below 10 usecs, depending on the system. There's no problem doing a non-preemptible udelay up to 10 usecs and we could use usleep above that.
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