package/kernel/mac80211/patches/337-mac80211-check-for-MCS-in-ieee80211_duration-before-.patch

   1 From: Felix Fietkau <nbd@nbd.name>
   2 Date: Wed, 14 Dec 2016 20:12:25 +0100
   3 Subject: [PATCH] mac80211: check for MCS in ieee80211_duration before fetching
   4  chanctx
   5
   6 Makes the code a bit more efficient
   7
   8 Signed-off-by: Felix Fietkau <nbd@nbd.name>
   9 ---
  10
  11 --- a/net/mac80211/tx.c
  12 +++ b/net/mac80211/tx.c
  13 @@ -63,6 +63,10 @@ static __le16 ieee80211_duration(struct
  14         struct ieee80211_chanctx_conf *chanctx_conf;
  15         u32 rate_flags = 0;
  16
  17 +       /* assume HW handles this */
  18 +       if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
  19 +               return 0;
  20 +
  21         rcu_read_lock();
  22         chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
  23         if (chanctx_conf) {
  24 @@ -71,10 +75,6 @@ static __le16 ieee80211_duration(struct
  25         }
  26         rcu_read_unlock();
  27
  28 -       /* assume HW handles this */
  29 -       if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
  30 -               return 0;
  31 -
  32         /* uh huh? */
  33         if (WARN_ON_ONCE(tx->rate.idx < 0))
  34                 return 0;