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    SubjectRe: [PATCH] i386: Fix a couple busy loops in mach_wakecpu.h:wait_for_init_deassert()
    Date
    On Thursday 16 August 2007 01:39, Satyam Sharma wrote:
    >
    > static inline void wait_for_init_deassert(atomic_t *deassert)
    > {
    > - while (!atomic_read(deassert));
    > + while (!atomic_read(deassert))
    > + cpu_relax();
    > return;
    > }

    For less-than-briliant people like me, it's totally non-obvious that
    cpu_relax() is needed for correctness here, not just to make P4 happy.

    IOW: "atomic_read" name quite unambiguously means "I will read
    this variable from main memory". Which is not true and creates
    potential for confusion and bugs.
    --
    vda
    -
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