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    SubjectRe: [PATCH 5/6] syslets: add generic syslets infrastructure
    So my radical ultra tired rant o the week...

    Rather than adding sys_indirect and syslets as is,

    * admit that this is beginning to look like a new ABI. explore the
    freedoms that that avenue opens...

    * (even more radical) I wonder what a tiny, SANE register-based
    bytecode interface might look like. Have a single page shared between
    kernel and userland, for each thread. Userland fills that page with
    bytecode, for a virtual machines with 256 registers -- where
    instructions roughly equate to syscalls.

    The common case -- a single syscall like open(2) -- would be a single
    byte bytecode, plus a couple VM register stores. The result is stored
    in another VM register.

    But this format enables more complex cases, where userland programs can
    pass strings of syscalls into the kernel, and let them execute until
    some exceptional condition occurs. Results would be stored in VM
    registers (or userland addresses stored in VM registers...).

    This sort of interface would be
    * fast

    * equate to the current syscall regime (easy to get existing APIs
    going... hopefully equivalent to glibc switching to a strange new
    SYSENTER variant)

    * be flexible enough to support a simple implementation today

    * be flexible enough to enable experiments into syscall parallelism (aka
    VM instruction parallelism <grin>)

    * be flexible enough to enable experiments into syscall batching

    One would probably want to add some simple logic opcodes in addition to
    opcodes for syscalls and such -- but this should not turn into Forth or
    Parrot or Java :)

    Thus, this new ABI can easily and immediately support all existing
    syscalls, while enabling

    Now to come up with a good programming API and model(s) to match this
    parallel, batched kernel<->userland interface...

    Jeff, very tired and delirious, so feel free to laugh at this,
    but I've been pondering this for a while

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      Last update: 2008-01-10 06:45    [W:0.022 / U:13.108 seconds]
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