Messages in this thread | | | Date | Thu, 4 Feb 2016 10:06:11 +0100 (CET) | From | Thomas Gleixner <> | Subject | Re: [PATCH v5] futex: Remove requirement for lock_page in get_futex_key |
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On Wed, 3 Feb 2016, Davidlohr Bueso wrote: > + * We are not calling into get_futex_key_refs() in file-backed > + * cases, therefore a successful atomic_inc return below will > + * guarantee that get_futex_key() will continue to imply MB (B).
Can you please make that "MB (B)" part a bit more outstanding. I really had to search for it.
> + */ > + if (WARN_ON_ONCE(!atomic_inc_not_zero(&inode->i_count))) { > + rcu_read_unlock(); > + put_page(page); > + > + goto again; > + }
Don't we need
smp_mb__after_atomic();
here to make it a full barrier on all architectures?
Thanks,
tglx
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