Re: [PATCH] volatile may be needed in rwsem

[Christian Borntraeger]

Joe Korty wrote:
> 'flags' should be declared volatile as rwsem_down_failed_common() spins
> waiting for this to change.  Untested.


You should use barrier() to prevent the compiler from optimizing reads away, 
not volatile. 
Here the compiler hopefully considers schedule() as a memory barrier. So 
everything should be fine.

cheers

Christian

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