Re: [PATCHv5 2/2] memory barrier: adding smp_mb__after_lock

[Herbert Xu]

Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx> 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,
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