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    SubjectRe: [PATCH 0/5] ftrace: to kill a daemon
    On Sat, 9 Aug 2008, Steven Rostedt wrote:
    > On Sat, 9 Aug 2008, Bodo Eggert wrote:
    > > Steven Rostedt <rostedt@goodmis.org> wrote:
    > > > On Sat, 9 Aug 2008, Andi Kleen wrote:
    > > >> Steven Rostedt <rostedt@goodmis.org> writes:

    > > >> > I'm stubborn, I want to get it right _and_ keep it fast.
    > > >>
    > > >> For me it would seem better to just not use two part 5 byte nops
    > > >> instead of adding such hacks. I doubt there are that many of them
    > > >> anyways. I bet you won't be able to measure any difference between the
    > > >> different nop types in any macro benchmark.
    > > >
    > > > I wish we had a true 5 byte nop. The alternative is a jmp 0, which is
    > > > measurable.
    > >
    > > Did you try short jumps? (0xeb 0x03 0x?? 0x?? 0x??)
    >
    > What would those last three bytes be?

    Anything, since the CPU will ignore them.

    My hope is that different kinds of jump will behaver differently,
    but I fear the side effect of the jmp (reread memory in case of
    self-modifying code) will cause the CPU to slow down anyway.
    --
    Is reading in the bathroom considered Multitasking?


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