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

From: Jamie Lokier (jamie_at_shareable.org)
Date: 01/31/04

  • Next message: Jim Faulkner: "major network performance difference between 2.4 and 2.6.2-rc2" 
    Date:	Sat, 31 Jan 2004 02:41:00 +0000
To: "Eric W. Biederman" <ebiederm@xmission.com>

    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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  • Next message: Jim Faulkner: "major network performance difference between 2.4 and 2.6.2-rc2"

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