Re: [PATCH 17/17] iwlwifi: mvm: add an option to dereference vif by id

[Kalle Valo <kvalo@codeaurora.org>]

Luca Coelho <luca@coelho.fi> writes:

> From: Sara Sharon <sara.sharon@intel.com>
>
> Currently whenever we get firmware notification with mac id,
> we iterate over all the interfaces to find the ID. This is a
> bit cumbersome. Instead, adding an array of RCU pointers, like
> we have for station IDs. This is not expensive space wise
> since we have only up to 4 active MACs, and not complicated
> code wise, since we have a clear point to init and de-init it.
>
> Signed-off-by: Sara Sharon <sara.sharon@intel.com>
> Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

[...]

> +static inline struct ieee80211_vif *
> +iwl_mvm_rcu_dereference_vif_id(struct iwl_mvm *mvm, u8 vif_id, bool rcu)
> +{
> +	if (WARN_ON(vif_id >= ARRAY_SIZE(mvm->vif_id_to_mac)))
> +		return NULL;
> +
> +	if (rcu)
> +		return rcu_dereference(mvm->vif_id_to_mac[vif_id]);
> +
> +	return rcu_dereference_protected(mvm->vif_id_to_mac[vif_id],
> +					 lockdep_is_held(&mvm->mutex));
> +}

No need to change anything, but IMHO foo(bar) and foo_protected(bar) is
a lot easier to read than foo(bar, true) and foo(bar, false).

-- 
Kalle Valo