Return-path: Received: from mail-bw0-f219.google.com ([209.85.218.219]:44505 "EHLO mail-bw0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751712Ab0ARQoI (ORCPT ); Mon, 18 Jan 2010 11:44:08 -0500 Received: by bwz19 with SMTP id 19so1853874bwz.28 for ; Mon, 18 Jan 2010 08:44:02 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by blech.mobile (Postfix) with ESMTP id DBF28340CAD for ; Mon, 18 Jan 2010 17:43:59 +0100 (CET) Received: from blech.mobile ([127.0.0.1]) by localhost (localhost [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xO4C78MIpd+7 for ; Mon, 18 Jan 2010 17:43:56 +0100 (CET) Received: from blech.mobile (localhost [127.0.0.1]) by blech.mobile (Postfix) with ESMTP id DC4CB340A21 for ; Mon, 18 Jan 2010 17:43:54 +0100 (CET) From: Christian Lamparter To: linux-wireless@vger.kernel.org Subject: [RFT][RFC] p54pci: revise tx locking Date: Mon, 18 Jan 2010 17:43:54 +0100 MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Message-Id: <201001181743.54392.chunkeey@googlemail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: This patch continues the effort which began with: "[PATCH] p54pci: move tx cleanup into tasklet". Thanks to these changes, p54pci's interrupt & tx cleanup routines can be made lock-less. Signed-off-by: Christian Lamparter --- If no one finds a bug till Friday, this will become a [PATCH]. --- diff --git a/drivers/net/wireless/p54/p54pci.c b/drivers/net/wireless/p54/p54pci.c index acc78e7..abf104e 100644 --- a/drivers/net/wireless/p54/p54pci.c +++ b/drivers/net/wireless/p54/p54pci.c @@ -238,7 +238,6 @@ static void p54p_check_tx_ring(struct ieee80211_hw *dev, u32 *index, int ring_index, struct p54p_desc *ring, u32 ring_limit, struct sk_buff **tx_buf) { - unsigned long flags; struct p54p_priv *priv = dev->priv; struct p54p_ring_control *ring_control = priv->ring_control; struct p54p_desc *desc; @@ -249,7 +248,6 @@ static void p54p_check_tx_ring(struct ieee80211_hw *dev, u32 *index, (*index) = idx = le32_to_cpu(ring_control->device_idx[1]); idx %= ring_limit; - spin_lock_irqsave(&priv->lock, flags); while (i != idx) { desc = &ring[i]; @@ -264,16 +262,12 @@ static void p54p_check_tx_ring(struct ieee80211_hw *dev, u32 *index, desc->len = 0; desc->flags = 0; - if (skb && FREE_AFTER_TX(skb)) { - spin_unlock_irqrestore(&priv->lock, flags); + if (skb && FREE_AFTER_TX(skb)) p54_free_skb(dev, skb); - spin_lock_irqsave(&priv->lock, flags); - } i++; i %= ring_limit; } - spin_unlock_irqrestore(&priv->lock, flags); } static void p54p_tasklet(unsigned long dev_id) @@ -306,7 +300,6 @@ static irqreturn_t p54p_interrupt(int irq, void *dev_id) struct p54p_priv *priv = dev->priv; __le32 reg; - spin_lock(&priv->lock); reg = P54P_READ(int_ident); if (unlikely(reg == cpu_to_le32(0xFFFFFFFF))) { goto out; @@ -321,15 +314,14 @@ static irqreturn_t p54p_interrupt(int irq, void *dev_id) complete(&priv->boot_comp); out: - spin_unlock(&priv->lock); return reg ? IRQ_HANDLED : IRQ_NONE; } static void p54p_tx(struct ieee80211_hw *dev, struct sk_buff *skb) { + unsigned long flags; struct p54p_priv *priv = dev->priv; struct p54p_ring_control *ring_control = priv->ring_control; - unsigned long flags; struct p54p_desc *desc; dma_addr_t mapping; u32 device_idx, idx, i; @@ -370,14 +362,14 @@ static void p54p_stop(struct ieee80211_hw *dev) unsigned int i; struct p54p_desc *desc; - tasklet_kill(&priv->tasklet); - P54P_WRITE(int_enable, cpu_to_le32(0)); P54P_READ(int_enable); udelay(10); free_irq(priv->pdev->irq, dev); + tasklet_kill(&priv->tasklet); + P54P_WRITE(dev_int, cpu_to_le32(ISL38XX_DEV_INT_RESET)); for (i = 0; i < ARRAY_SIZE(priv->rx_buf_data); i++) {