ath9k: optimize ath9k_flush

Instead of checking the queues in a loop with hardcoded sleep times
inbetween, use a wait queue to trigger queue checks after the tx
processing tasklet has run.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 0783e50f44b2f257d8af73e68a4f44666be99737..5e5d5cb2458c0a9c492b8ea74aaf83bcc91a4568 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -754,6 +754,7 @@ struct ath_softc {
        struct work_struct hw_check_work;
        struct work_struct hw_reset_work;
        struct completion paprd_complete;
+       wait_queue_head_t tx_wait;
 
        unsigned int hw_busy_count;
        unsigned long sc_flags;

diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 65a2add3b6767c3da117cbf54a3a63fedec233d1..8f4c1674b76e2a2f1c301d9e3796a4d3ffea1906 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -691,6 +691,7 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
        common = ath9k_hw_common(ah);
        sc->dfs_detector = dfs_pattern_detector_init(common, NL80211_DFS_UNSET);
        sc->tx99_power = MAX_RATE_POWER + 1;
+       init_waitqueue_head(&sc->tx_wait);
 
        if (!pdata) {
                ah->ah_flags |= AH_USE_EEPROM;

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index f86404a70a73a668a8d911f734994fd915d3dda8..b1dcf89138d30d4ce8899e9a117ee96ac29212e5 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -504,6 +504,8 @@ void ath9k_tasklet(unsigned long data)
                        ath_tx_edma_tasklet(sc);
                else
                        ath_tx_tasklet(sc);
+
+               wake_up(&sc->tx_wait);
        }
 
        ath9k_btcoex_handle_interrupt(sc, status);
@@ -1837,13 +1839,31 @@ static void ath9k_set_coverage_class(struct ieee80211_hw *hw, u8 coverage_class)
        mutex_unlock(&sc->mutex);
 }
 
+static bool ath9k_has_tx_pending(struct ath_softc *sc)
+{
+       int i, npend;
+
+       for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
+               if (!ATH_TXQ_SETUP(sc, i))
+                       continue;
+
+               if (!sc->tx.txq[i].axq_depth)
+                       continue;
+
+               npend = ath9k_has_pending_frames(sc, &sc->tx.txq[i]);
+               if (npend)
+                       break;
+       }
+
+       return !!npend;
+}
+
 static void ath9k_flush(struct ieee80211_hw *hw, u32 queues, bool drop)
 {
        struct ath_softc *sc = hw->priv;
        struct ath_hw *ah = sc->sc_ah;
        struct ath_common *common = ath9k_hw_common(ah);
-       int timeout = 200; /* ms */
-       int i, j;
+       int timeout = HZ / 5; /* 200 ms */
        bool drain_txq;
 
        mutex_lock(&sc->mutex);
@@ -1861,25 +1881,9 @@ static void ath9k_flush(struct ieee80211_hw *hw, u32 queues, bool drop)
                return;
        }
 
-       for (j = 0; j < timeout; j++) {
-               bool npend = false;
-
-               if (j)
-                       usleep_range(1000, 2000);
-
-               for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
-                       if (!ATH_TXQ_SETUP(sc, i))
-                               continue;
-
-                       npend = ath9k_has_pending_frames(sc, &sc->tx.txq[i]);
-
-                       if (npend)
-                               break;
-               }
-
-               if (!npend)
-                   break;
-       }
+       if (wait_event_timeout(sc->tx_wait, !ath9k_has_tx_pending(sc),
+                              timeout) > 0)
+               drop = false;
 
        if (drop) {
                ath9k_ps_wakeup(sc);