From d559e303b17826a6e4879fc6f12d929562c4061c Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 18 Oct 2017 13:44:23 +0200 Subject: [PATCH] mac80211: avoid looking up tid_tx/tid_rx from timers There's no need to re-lookup the data structures now that we actually get them immediately with from_timer(), just avoid that. The struct has to be valid anyway, otherwise the timer object itself would no longer be valid, and we can't have a different version of the struct since only a single session per TID is permitted. Signed-off-by: Johannes Berg --- net/mac80211/agg-rx.c | 17 +++-------------- net/mac80211/agg-tx.c | 31 ++++++++----------------------- 2 files changed, 11 insertions(+), 37 deletions(-) diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index d444752dbf40..35e94483fb8c 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -153,27 +153,16 @@ EXPORT_SYMBOL(ieee80211_stop_rx_ba_session); */ static void sta_rx_agg_session_timer_expired(struct timer_list *t) { - struct tid_ampdu_rx *tid_rx_timer = - from_timer(tid_rx_timer, t, session_timer); - struct sta_info *sta = tid_rx_timer->sta; - u8 tid = tid_rx_timer->tid; - struct tid_ampdu_rx *tid_rx; + struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer); + struct sta_info *sta = tid_rx->sta; + u8 tid = tid_rx->tid; unsigned long timeout; - rcu_read_lock(); - tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]); - if (!tid_rx) { - rcu_read_unlock(); - return; - } - timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout); if (time_is_after_jiffies(timeout)) { mod_timer(&tid_rx->session_timer, timeout); - rcu_read_unlock(); return; } - rcu_read_unlock(); ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n", sta->sta.addr, tid); diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c index 5f8ab5be369f..a04df962129c 100644 --- a/net/mac80211/agg-tx.c +++ b/net/mac80211/agg-tx.c @@ -429,18 +429,12 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, */ static void sta_addba_resp_timer_expired(struct timer_list *t) { - struct tid_ampdu_tx *tid_tx_timer = - from_timer(tid_tx_timer, t, addba_resp_timer); - struct sta_info *sta = tid_tx_timer->sta; - u8 tid = tid_tx_timer->tid; - struct tid_ampdu_tx *tid_tx; + struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer); + struct sta_info *sta = tid_tx->sta; + u8 tid = tid_tx->tid; /* check if the TID waits for addBA response */ - rcu_read_lock(); - tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); - if (!tid_tx || - test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { - rcu_read_unlock(); + if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { ht_dbg(sta->sdata, "timer expired on %pM tid %d not expecting addBA response\n", sta->sta.addr, tid); @@ -451,7 +445,6 @@ static void sta_addba_resp_timer_expired(struct timer_list *t) sta->sta.addr, tid); ieee80211_stop_tx_ba_session(&sta->sta, tid); - rcu_read_unlock(); } void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) @@ -529,29 +522,21 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) */ static void sta_tx_agg_session_timer_expired(struct timer_list *t) { - struct tid_ampdu_tx *tid_tx_timer = - from_timer(tid_tx_timer, t, session_timer); - struct sta_info *sta = tid_tx_timer->sta; - u8 tid = tid_tx_timer->tid; - struct tid_ampdu_tx *tid_tx; + struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer); + struct sta_info *sta = tid_tx->sta; + u8 tid = tid_tx->tid; unsigned long timeout; - rcu_read_lock(); - tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); - if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { - rcu_read_unlock(); + if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { return; } timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); if (time_is_after_jiffies(timeout)) { mod_timer(&tid_tx->session_timer, timeout); - rcu_read_unlock(); return; } - rcu_read_unlock(); - ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", sta->sta.addr, tid); -- 2.30.2