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    SubjectRE: [PATCH 9/24] make atomic_read() behave consistently on ia64
    > Use atomic64_read to read an atomic64_t.

    Thanks Andreas!

    Chris: This bug is why the 8-byte loads got changed to 4-byte + sign-extend
    by your change to atomic_read().

    With this applied together with shuffling the volatile from the
    declaration to the usage (in both atomic_read() and atomic_set()
    the generated code *almost* reverts to the original.

    There are some differences where ld4 have turned into ld8 though.
    Are these bugs in the use of atomic_add() and atomic_sub(). E.g.
    the first of these changes is in: ipc/msg.c:freeque() where we have:

    atomic_sub(msg->q_cbytes, &msg_bytes);

    Now the type of msg->q_cbytes is "unsigned long" ... so it seems a
    poor idea to subtract such a large typed object from "msg_bytes"
    which is a mere slip of an atomic_t.

    Or is there some other type-wrangling that needs to happen in
    include/asm-ia64/atomic.h? There are a total of nineteen of
    these ld4->ld8 transforms.

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      Last update: 2007-08-11 00:37    [W:0.021 / U:0.244 seconds]
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