Messages in this thread | | | Date | Mon, 6 Jun 2011 23:54:21 +0200 | From | Ingo Molnar <> | Subject | Re: [PATCH v5 9/9] x86-64: Add CONFIG_UNSAFE_VSYSCALLS to feature-removal-schedule |
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* Andrew Lutomirski <luto@mit.edu> wrote:
> > don't even bother making it a config option for now. If we can > > replace the vsyscall page with a page fault or int3 or whatever, > > and it's only used for the 'time()' system call, just do it. > > Really? > > I won't personally complain about the 200+ ns hit, but I'm sure > someone will cc: me on a regression report if there's no option.
Well, for 0.2 usecs to show up one would have to do like a million of them per second.
Why an application would want to query the *same value* from the kernel a million times per second is beyond me. vgettimeofday()? Sure. But vtime()?
Thanks,
Ingo
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