From patchwork Fri Jun 24 12:08:13 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rajkumar Manoharan X-Patchwork-Id: 915952 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p5OC8JkE021369 for ; Fri, 24 Jun 2011 12:08:19 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753957Ab1FXMIR (ORCPT ); Fri, 24 Jun 2011 08:08:17 -0400 Received: from mail.atheros.com ([12.19.149.2]:23932 "EHLO mail.atheros.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752948Ab1FXMIQ (ORCPT ); Fri, 24 Jun 2011 08:08:16 -0400 Received: from mail.atheros.com ([10.234.20.105]) by sidewinder.atheros.com for ; Fri, 24 Jun 2011 05:07:40 -0700 Received: from mail.atheros.com (10.12.4.42) by SC1EXHC-01.global.atheros.com (10.234.20.111) with Microsoft SMTP Server (TLS) id 8.2.213.0; Fri, 24 Jun 2011 05:08:14 -0700 Received: by mail.atheros.com (sSMTP sendmail emulation); Fri, 24 Jun 2011 17:38:13 +0530 From: Rajkumar Manoharan To: CC: , Rajkumar Manoharan Subject: [PATCH v2] ath9k: Fix locking issue during tx completion Date: Fri, 24 Jun 2011 17:38:13 +0530 Message-ID: <1308917293-7828-1-git-send-email-rmanoharan@atheros.com> X-Mailer: git-send-email 1.7.5.2 MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Fri, 24 Jun 2011 12:08:19 +0000 (UTC) From: Rajkumar Manoharan The received tx status of aggregated frame without BlockAck may cause deaf state in AR5416 cards. So the driver does a reset to recover. When this happens, we release the pcu_lock before doing a reset as ath_rest acquires pcu_lock. This is ugly and also not atomic. Fixing this addresses the TX DMA failure also. ath_tx_complete_aggr can be called from different paths which takes different variants of spin_lock. This patch also addresses the following warning. WARNING: at kernel/timer.c:1011 del_timer_sync+0x4e/0x50() Call Trace: [] warn_slowpath_common+0x7a/0xb0 [] warn_slowpath_null+0x15/0x20 [] del_timer_sync+0x4e/0x50 [] ath_reset+0x3e/0x210 [ath9k] [] ? _raw_spin_unlock_bh+0x1f/0x30 [] ath_tx_complete_aggr.isra.26+0x54a/0xa40 [ath9k] Signed-off-by: Rajkumar Manoharan --- v2: spin_lock_bh replaced by spin_lock bh context drivers/net/wireless/ath/ath9k/beacon.c | 2 ++ drivers/net/wireless/ath/ath9k/main.c | 13 +++++++++---- drivers/net/wireless/ath/ath9k/xmit.c | 7 +++---- 3 files changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c index 0b6e3b6..e19a230 100644 --- a/drivers/net/wireless/ath/ath9k/beacon.c +++ b/drivers/net/wireless/ath/ath9k/beacon.c @@ -385,7 +385,9 @@ void ath_beacon_tasklet(unsigned long data) ath_dbg(common, ATH_DBG_BSTUCK, "beacon is officially stuck\n"); sc->sc_flags |= SC_OP_TSF_RESET; + spin_lock(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock(&sc->sc_pcu_lock); } return; diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 5ae303b..9098aaa 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -617,8 +617,11 @@ void ath_hw_check(struct work_struct *work) ath_dbg(common, ATH_DBG_RESET, "Possible baseband hang, " "busy=%d (try %d)\n", busy, sc->hw_busy_count + 1); if (busy >= 99) { - if (++sc->hw_busy_count >= 3) + if (++sc->hw_busy_count >= 3) { + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); + } } else if (busy >= 0) sc->hw_busy_count = 0; @@ -637,7 +640,9 @@ static void ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum) /* Rx is hung for more than 500ms. Reset it */ ath_dbg(common, ATH_DBG_RESET, "Possible RX hang, resetting"); + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); count = 0; } } else @@ -674,7 +679,9 @@ void ath9k_tasklet(unsigned long data) if ((status & ATH9K_INT_FATAL) || (status & ATH9K_INT_BB_WATCHDOG)) { + spin_lock(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock(&sc->sc_pcu_lock); return; } @@ -980,7 +987,6 @@ int ath_reset(struct ath_softc *sc, bool retry_tx) del_timer_sync(&common->ani.timer); ath9k_ps_wakeup(sc); - spin_lock_bh(&sc->sc_pcu_lock); ieee80211_stop_queues(hw); @@ -1023,7 +1029,6 @@ int ath_reset(struct ath_softc *sc, bool retry_tx) } ieee80211_wake_queues(hw); - spin_unlock_bh(&sc->sc_pcu_lock); /* Start ANI */ if (!common->disable_ani) @@ -2326,9 +2331,9 @@ static void ath9k_flush(struct ieee80211_hw *hw, bool drop) ath9k_ps_wakeup(sc); spin_lock_bh(&sc->sc_pcu_lock); drain_txq = ath_drain_all_txq(sc, false); - spin_unlock_bh(&sc->sc_pcu_lock); if (!drain_txq) ath_reset(sc, false); + spin_unlock_bh(&sc->sc_pcu_lock); ath9k_ps_restore(sc); ieee80211_wake_queues(hw); diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index ec012b4..a1fed6c 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -565,11 +565,8 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq, rcu_read_unlock(); - if (needreset) { - spin_unlock_bh(&sc->sc_pcu_lock); + if (needreset) ath_reset(sc, false); - spin_lock_bh(&sc->sc_pcu_lock); - } } static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf, @@ -2169,7 +2166,9 @@ static void ath_tx_complete_poll_work(struct work_struct *work) if (needreset) { ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_RESET, "tx hung, resetting the chip\n"); + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); } ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,