From patchwork Tue Oct 12 08:53:51 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ido Yariv X-Patchwork-Id: 247281 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id o9C8sEVp018466 for ; Tue, 12 Oct 2010 08:54:14 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757072Ab0JLIyK (ORCPT ); Tue, 12 Oct 2010 04:54:10 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:61051 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756936Ab0JLIyG (ORCPT ); Tue, 12 Oct 2010 04:54:06 -0400 Received: by wye20 with SMTP id 20so1182930wye.19 for ; Tue, 12 Oct 2010 01:54:04 -0700 (PDT) Received: by 10.227.20.69 with SMTP id e5mr6733948wbb.87.1286873642501; Tue, 12 Oct 2010 01:54:02 -0700 (PDT) Received: from localhost.localdomain (93-172-238-74.bb.netvision.net.il [93.172.238.74]) by mx.google.com with ESMTPS id h29sm6893053wbc.15.2010.10.12.01.54.01 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 12 Oct 2010 01:54:02 -0700 (PDT) From: Ido Yariv To: Luciano Coelho , linux-wireless@vger.kernel.org Cc: Ido Yariv Subject: [PATCH v2 2/4] wl1271: Fix TX starvation Date: Tue, 12 Oct 2010 10:53:51 +0200 Message-Id: <1286873633-10080-3-git-send-email-ido@wizery.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: <1286873633-10080-1-git-send-email-ido@wizery.com> References: <1286873633-10080-1-git-send-email-ido@wizery.com> 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-4.2.3 (demeter1.kernel.org [140.211.167.41]); Tue, 12 Oct 2010 08:54:14 +0000 (UTC) diff --git a/drivers/net/wireless/wl12xx/wl1271.h b/drivers/net/wireless/wl12xx/wl1271.h index 8a4cd76..4a034a3 100644 --- a/drivers/net/wireless/wl12xx/wl1271.h +++ b/drivers/net/wireless/wl12xx/wl1271.h @@ -351,6 +351,7 @@ struct wl1271 { #define WL1271_FLAG_IDLE_REQUESTED (11) #define WL1271_FLAG_PSPOLL_FAILURE (12) #define WL1271_FLAG_STA_STATE_SENT (13) +#define WL1271_FLAG_FW_TX_BUSY (14) unsigned long flags; struct wl1271_partition_set part; diff --git a/drivers/net/wireless/wl12xx/wl1271_main.c b/drivers/net/wireless/wl12xx/wl1271_main.c index 48a4b99..18aff22 100644 --- a/drivers/net/wireless/wl12xx/wl1271_main.c +++ b/drivers/net/wireless/wl12xx/wl1271_main.c @@ -481,9 +481,9 @@ static void wl1271_fw_status(struct wl1271 *wl, total += cnt; } - /* if more blocks are available now, schedule some tx work */ - if (total && !skb_queue_empty(&wl->tx_queue)) - ieee80211_queue_work(wl->hw, &wl->tx_work); + /* if more blocks are available now, tx work can be scheduled */ + if (total) + clear_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags); /* update the host-chipset time offset */ getnstimeofday(&ts); @@ -537,6 +537,16 @@ static void wl1271_irq_work(struct work_struct *work) (wl->tx_results_count & 0xff)) wl1271_tx_complete(wl); + /* Check if any tx blocks were freed */ + if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags) && + !skb_queue_empty(&wl->tx_queue)) { + /* + * In order to avoid starvation of the TX path, + * call the work function directly. + */ + wl1271_tx_work_locked(wl); + } + wl1271_rx(wl, wl->fw_status); } @@ -867,7 +877,8 @@ static int wl1271_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb) * before that, the tx_work will not be initialized! */ - ieee80211_queue_work(wl->hw, &wl->tx_work); + if (!test_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags)) + ieee80211_queue_work(wl->hw, &wl->tx_work); /* * The workqueue is slow to process the tx_queue and we need stop diff --git a/drivers/net/wireless/wl12xx/wl1271_tx.c b/drivers/net/wireless/wl12xx/wl1271_tx.c index b13b373..cf32a77 100644 --- a/drivers/net/wireless/wl12xx/wl1271_tx.c +++ b/drivers/net/wireless/wl12xx/wl1271_tx.c @@ -204,9 +204,8 @@ u32 wl1271_tx_enabled_rates_get(struct wl1271 *wl, u32 rate_set) return enabled_rates; } -void wl1271_tx_work(struct work_struct *work) +void wl1271_tx_work_locked(struct wl1271 *wl) { - struct wl1271 *wl = container_of(work, struct wl1271, tx_work); struct sk_buff *skb; bool woken_up = false; u32 sta_rates = 0; @@ -223,8 +222,6 @@ void wl1271_tx_work(struct work_struct *work) spin_unlock_irqrestore(&wl->wl_lock, flags); } - mutex_lock(&wl->mutex); - if (unlikely(wl->state == WL1271_STATE_OFF)) goto out; @@ -260,6 +257,8 @@ void wl1271_tx_work(struct work_struct *work) * Queue back last skb, and stop aggregating. */ skb_queue_head(&wl->tx_queue, skb); + /* No work left, avoid scheduling redundant tx work */ + set_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags); goto out_ack; } else if (ret < 0) { dev_kfree_skb(skb); @@ -283,7 +282,14 @@ out_ack: out: if (woken_up) wl1271_ps_elp_sleep(wl); +} +void wl1271_tx_work(struct work_struct *work) +{ + struct wl1271 *wl = container_of(work, struct wl1271, tx_work); + + mutex_lock(&wl->mutex); + wl1271_tx_work_locked(wl); mutex_unlock(&wl->mutex); } diff --git a/drivers/net/wireless/wl12xx/wl1271_tx.h b/drivers/net/wireless/wl12xx/wl1271_tx.h index d12a129..f1c9065 100644 --- a/drivers/net/wireless/wl12xx/wl1271_tx.h +++ b/drivers/net/wireless/wl12xx/wl1271_tx.h @@ -140,6 +140,7 @@ static inline int wl1271_tx_get_queue(int queue) } void wl1271_tx_work(struct work_struct *work); +void wl1271_tx_work_locked(struct wl1271 *wl); void wl1271_tx_complete(struct wl1271 *wl); void wl1271_tx_reset(struct wl1271 *wl); void wl1271_tx_flush(struct wl1271 *wl);