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    SubjectRe: [PATCHv5 2/2] memory barrier: adding smp_mb__after_lock
    Herbert Xu a écrit :
    > Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:
    >> Why don't we create a read_lock without acquire semantic instead (e.g.
    >> read_lock_nomb(), or something with a better name like __read_lock()) ?
    >> On architectures where memory barriers are needed to provide the acquire
    >> semantic, it would be faster to do :
    >>
    >> __read_lock();
    >> smp_mb();
    >>
    >> than :
    >>
    >> read_lock(); <- e.g. lwsync + isync or something like that
    >> smp_mb(); <- full sync.
    >
    > Hmm, why do we even care when read_lock should just die?
    >
    > Cheers,

    +1 :)

    Do you mean using a spinlock instead or what ?

    Also, how many arches are able to have a true __read_lock()
    (or __spin_lock() if that matters), without acquire semantic ?
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