Re: [PATCH v2 05/10] rtlwifi: enable mac80211 fast-tx support

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2018-01-16 at 21:12 +0100, Arend van Spriel wrote:
> 
> When I saw this flying by I had the same feeling. This is clearly not 
> how it was intended although you could interpret the comments of the 
> .set_frag_threshold() callback and IEEE80211_HW_SUPPORTS_TX_FRAG. 
> However, the fragmentation threshold is a user-configurable stack 
> parameter as per the standard. This patch effectively kill that option 
> for the user although there may be RF conditions in which fragmentation 
> can help. Having the user configure a fragmentation threshold of 2346 
> also disables fragmentation and allows mac80211 to use cached fastpath.
> 

        /* fast-xmit doesn't handle fragmentation at all */
        if (local->hw.wiphy->frag_threshold != (u32)-1 &&
            !ieee80211_hw_check(&local->hw, SUPPORTS_TX_FRAG))
                goto out;

so internally at least it has to be -1, does 2346 really do that?
remember, but it might well :-)

johannes