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> #endif /* !CONFIG_FUTEX */ > > +/** > + * struct futex_mm_data - Futex related per MM data > + * @phash_lock: Mutex to protect the private hash operations > + * @phash: RCU managed pointer to the private hash > + * @phash_new: Pointer to a newly allocated private hash > + * @phash_batches: Batch state for RCU synchronization > + * @phash_rcu: RCU head for call_rcu() > + * @phash_atomic: Aggregate value for @phash_ref > + * @phash_ref: Per CPU reference counter for a private hash > + */ > +struct futex_mm_data { > +#ifdef CONFIG_FUTEX_PRIVATE_HASH > + struct mutex phash_lock; > + struct futex_private_hash __rcu *phash; > + struct futex_private_hash *phash_new; > + unsigned long phash_batches; > + struct rcu_head phash_rcu; > + atomic_long_t phash_atomic; > + unsigned int __percpu *phash_ref; > +#endif > +}; In the previous patch you use the approach of declaring an empty structure within the #else, and here the content of the struct is conditional. Preferably pick one approach ? Other than this minor nit: Reviewed-by: Mathieu Desnoyers -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com