From: Johannes Berg Date: Wed, 15 Jan 2020 12:25:50 +0100 Subject: [PATCH] mac80211: use more bits for ack_frame_id MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It turns out that this wasn't a good idea, I hit a test failure in hwsim due to this. That particular failure was easily worked around, but it raised questions: if an AP needs to, for example, send action frames to each connected station, the current limit is nowhere near enough (especially if those stations are sleeping and the frames are queued for a while.) Shuffle around some bits to make more room for ack_frame_id to allow up to 8192 queued up frames, that's enough for queueing 4 frames to each connected station, even at the maximum of 2007 stations on a single AP. We take the bits from band (which currently only 2 but I leave 3 in case we add another band) and from the hw_queue, which can only need 4 since it has a limit of 16 queues. Fixes: 6912daed05e1 ("mac80211: Shrink the size of ack_frame_id to make room for tx_time_est") Signed-off-by: Johannes Berg Acked-by: Toke Høiland-Jørgensen --- --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -1004,12 +1004,11 @@ ieee80211_rate_get_vht_nss(const struct struct ieee80211_tx_info { /* common information */ u32 flags; - u8 band; - - u8 hw_queue; - - u16 ack_frame_id:6; - u16 tx_time_est:10; + u32 band:3, + ack_frame_id:13, + hw_queue:4, + tx_time_est:10; + /* 2 free bits */ union { struct { --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -3449,7 +3449,7 @@ int ieee80211_attach_ack_skb(struct ieee spin_lock_irqsave(&local->ack_status_lock, spin_flags); id = idr_alloc(&local->ack_status_frames, ack_skb, - 1, 0x40, GFP_ATOMIC); + 1, 0x2000, GFP_ATOMIC); spin_unlock_irqrestore(&local->ack_status_lock, spin_flags); if (id < 0) { --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2458,7 +2458,7 @@ static int ieee80211_store_ack_skb(struc spin_lock_irqsave(&local->ack_status_lock, flags); id = idr_alloc(&local->ack_status_frames, ack_skb, - 1, 0x40, GFP_ATOMIC); + 1, 0x2000, GFP_ATOMIC); spin_unlock_irqrestore(&local->ack_status_lock, flags); if (id >= 0) {