Re: [RFC][PATCH] linux-2.6.2-rc2_vsyscall-gtod_B1.patch

[Jamie Lokier]

Eric W. Biederman wrote:
> With the x86-64 optimized vsyscall the syscall number does
> not need to be placed into a register, because you have used
> the proper entry point.  For any syscall worth tuning in
> user space I suspect that level of optimization would be
> beneficial.  A fast call path that does not waste a register.

The cost of loading a constant into a register is _much_ lower than
the cost of indirect jumps which we have been discussing.

-- Jamie
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